Articles | Volume 18, issue 18
https://doi.org/10.5194/acp-18-13321-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue:
https://doi.org/10.5194/acp-18-13321-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
18 Sep 2018
Research article |
| 18 Sep 2018
| 18 Sep 2018
Prediction of photosynthesis in Scots pine ecosystems across Europe by a needle-level theory
Pertti Hari
CORRESPONDING AUTHOR
Institute for Atmospheric and Earth System Research INAR, Department of Forest Sciences, Faculty of Agriculture and Forestry, P.O. Box 27, 00014, University of Helsinki, Finland
Steffen Noe
Department of Plant Physiology, Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi 1, 51014 Tartu, Estonia
Sigrid Dengel
Lawrence Berkeley National Laboratory, Climate and Ecosystem Sciences Division, 1 Cyclotron Road 84-155, Mail Stop 074-0316, Berkeley, CA 94720-8118, USA
Jan Elbers
Wageningen University and Research, Water Systems and Global Change Group, P.O. Box 47, 6700AA Wageningen, the Netherlands
Bert Gielen
Department of Biology, University of Antwerp, 2610 Wilrijk, Belgium
Veli-Matti Kerminen
Institute for Atmospheric and Earth System Research INAR, Faculty of Science, P.O. Box 68, 00014, University of Helsinki, Finland
Bart Kruijt
Wageningen University and Research, Water Systems and Global Change Group, P.O. Box 47, 6700AA Wageningen, the Netherlands
Liisa Kulmala
Institute for Atmospheric and Earth System Research INAR, Department of Forest Sciences, Faculty of Agriculture and Forestry, P.O. Box 27, 00014, University of Helsinki, Finland
Anders Lindroth
Department of Physical Geography and Ecosystem Sciences, Lund University, 22362 Lund, Sweden
Ivan Mammarella
Institute for Atmospheric and Earth System Research INAR, Faculty of Science, P.O. Box 68, 00014, University of Helsinki, Finland
Tuukka Petäjä
Institute for Atmospheric and Earth System Research INAR, Faculty of Science, P.O. Box 68, 00014, University of Helsinki, Finland
Guy Schurgers
University of Copenhagen, Department of Geosciences and Natural Resource Management, Øster Voldgade 10, 1350 Copenhagen, Denmark
Anni Vanhatalo
Institute for Atmospheric and Earth System Research INAR, Department of Forest Sciences, Faculty of Agriculture and Forestry, P.O. Box 27, 00014, University of Helsinki, Finland
Markku Kulmala
Institute for Atmospheric and Earth System Research INAR, Faculty of Science, P.O. Box 68, 00014, University of Helsinki, Finland
Jaana Bäck
Institute for Atmospheric and Earth System Research INAR, Department of Forest Sciences, Faculty of Agriculture and Forestry, P.O. Box 27, 00014, University of Helsinki, Finland
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Fidel Pankratov, Alexander Mahura, Oleg Katz, Tuukka Petäjä, Valentin Popov, and Vladimir Masloboev
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Anastasia Lampilahti, Olga Garmash, Diego Aliaga, Mikhail Arshinov, Denis Davydov, Boris Belan, Janne Lampilahti, Veli-Matti Kerminen, Tuukka Petäjä, Markku Kulmala, and Ekaterina Ezhova
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Benjamin Heutte, Nora Bergner, Hélène Angot, Jakob B. Pernov, Lubna Dada, Jessica A. Mirrielees, Ivo Beck, Andrea Baccarini, Matthew Boyer, Jessie M. Creamean, Kaspar R. Daellenbach, Imad El Haddad, Markus M. Frey, Silvia Henning, Tiia Laurila, Vaios Moschos, Tuukka Petäjä, Kerri A. Pratt, Lauriane L. J. Quéléver, Matthew D. Shupe, Paul Zieger, Tuija Jokinen, and Julia Schmale
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Tinghan Zhang, Ximeng Qi, Janne Lampilahti, Liangduo Chen, Xuguang Chi, Wei Nie, Xin Huang, Zehao Zou, Wei Du, Tom Kokkonen, Tuukka Petäjä, Katrianne Lehtipalo, Veli-Matti Kerminen, Aijun Ding, and Markku Kulmala
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Laura M. van der Poel, Laurent V. Bataille, Bart Kruijt, Wietse Franssen, Wilma Jans, Jan Biermann, Anne Rietman, Alex J. V. Buzacott, Ype van der Velde, Ruben Boelens, and Ronald W. A. Hutjes
EGUsphere, https://doi.org/10.5194/egusphere-2025-431, https://doi.org/10.5194/egusphere-2025-431, 2025
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We combine two types of carbon dioxide (CO2) data from Dutch peatlands in a machine learning model: from fixed measurement towers and from a light research aircraft. We find that emissions increase with deeper water table depths (WTD) by 4.6 tonnes CO2 per hectare per year, per 10 cm deeper WTD on average. The effect is stronger in winter than in summer and varies between locations. This variability should be taken into account when developing mitigation measures.
Xinyang Li, Tuomo Nieminen, Rima Baalbaki, Putian Zhou, Pauli Paasonen, Risto Makkonen, Martha Arbayani Zaidan, Nina Sarnela, Chao Yan, Tujia Jokinen, Imre Salma, Máté Vörösmarty, Tuukka Petäjä, Veli-Matti Kerminen, Markku Kulmala, and Lubna Dada
Aerosol Research Discuss., https://doi.org/10.5194/ar-2025-3, https://doi.org/10.5194/ar-2025-3, 2025
Revised manuscript accepted for AR
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Ulrike Proske, Michael P. Adams, Grace C. E. Porter, Mark A. Holden, Jaana Bäck, and Benjamin J. Murray
Atmos. Chem. Phys., 25, 979–995, https://doi.org/10.5194/acp-25-979-2025, https://doi.org/10.5194/acp-25-979-2025, 2025
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Ice-nucleating particles (INPs) aid the freezing of water droplets in clouds and thus modify cloud properties. In a campaign in a Finnish boreal forest, biological INPs were observed, despite many of their potential biological sources being snow-covered. We sampled tree-dwelling lichens that were not covered in snow and tested their ice nucleation ability in the laboratory. We found that the lichen harbours INPs, which may be important in similar snowy environments.
Yiliang Liu, Arttu Yli-Kujala, Fabian Schmidt-Ott, Sebastian Holm, Lauri Ahonen, Tommy Chan, Joonas Enroth, Joonas Vanhanen, Runlong Cai, Tuukka Petäjä, Markku Kulmala, Yang Chen, and Juha Kangasluoma
Atmos. Meas. Tech., 18, 431–442, https://doi.org/10.5194/amt-18-431-2025, https://doi.org/10.5194/amt-18-431-2025, 2025
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Accurate measurement of nanoparticles is crucial for understanding their impact on new particle formation and climate change. In this study, we calibrated the Particle Size Magnifier version 2.0 (PSM 2.0), using both laboratory-generated and atmospheric particles. Some differences were observed in the calibration results, with direct calibration using atmospheric particles enhancing measurement accuracy.
Pan Wang, Yue Zhao, Jiandong Wang, Veli-Matti Kerminen, Jingkun Jiang, and Chenxi Li
EGUsphere, https://doi.org/10.5194/egusphere-2024-3666, https://doi.org/10.5194/egusphere-2024-3666, 2025
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We developed a numerical model to explore how the charge state of newly formed atmospheric particles evolves during growth and how this relates to ion-induced nucleation rates. We identify the governing factors of particle charging and further apply neural networks to predict particle charge states and estimate ion induced nucleation rates. This study offers insights into particle charging dynamics and introduces new methods for assessing ion induced nucleation in atmospheric research.
Diego Aliaga, Victoria A. Sinclair, Radovan Krejci, Marcos Andrade, Paulo Artaxo, Luis Blacutt, Runlong Cai, Samara Carbone, Yvette Gramlich, Liine Heikkinen, Dominic Heslin-Rees, Wei Huang, Veli-Matti Kerminen, Alkuin Maximilian Koenig, Markku Kulmala, Paolo Laj, Valeria Mardoñez-Balderrama, Claudia Mohr, Isabel Moreno, Pauli Paasonen, Wiebke Scholz, Karine Sellegri, Laura Ticona, Gaëlle Uzu, Fernando Velarde, Alfred Wiedensohler, Doug Worsnop, Cheng Wu, Chen Xuemeng, Qiaozhi Zha, and Federico Bianchi
Aerosol Research, 3, 15–44, https://doi.org/10.5194/ar-3-15-2025, https://doi.org/10.5194/ar-3-15-2025, 2025
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This study examines new particle formation (NPF) in the Bolivian Andes at Chacaltaya mountain (CHC) and the urban El Alto–La Paz area (EAC). Days are clustered into four categories based on NPF intensity. Differences in particle size, precursor gases, and pollution levels are found. High NPF intensities increased Aitken mode particle concentrations at both sites, while volcanic influence selectively diminished NPF intensity at CHC but not EAC. This study highlights NPF dynamics in the Andes.
Ekaterina Ezhova, Topi Laanti, Anna Lintunen, Pasi Kolari, Tuomo Nieminen, Ivan Mammarella, Keijo Heljanko, and Markku Kulmala
Biogeosciences, 22, 257–288, https://doi.org/10.5194/bg-22-257-2025, https://doi.org/10.5194/bg-22-257-2025, 2025
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Machine learning (ML) models are gaining popularity in biogeosciences. They are applied as gap-filling methods and used to upscale carbon fluxes to larger areas. Here we use explainable artificial intelligence (XAI) methods to elucidate the performance of machine learning models for carbon dioxide fluxes in boreal forests. We show that statistically equal models treat input variables differently. XAI methods can help scientists make informed decisions when applying ML models in their research.
Otso Peräkylä, Erkka Rinne, Ekaterina Ezhova, Anna Lintunen, Annalea Lohila, Juho Aalto, Mika Aurela, Pasi Kolari, and Markku Kulmala
Biogeosciences, 22, 153–179, https://doi.org/10.5194/bg-22-153-2025, https://doi.org/10.5194/bg-22-153-2025, 2025
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Forests are seen as good for climate. Yet, in areas with snow, trees break up the white snow surface and absorb more sunlight than open areas. This has a warming effect, negating some of the climate benefit of trees. We studied two site pairs in Finland, both with an open peatland and a forest. We found that the later the snow melts, the more extra energy the forest absorbs as compared to the peatland. This has implications for the future, as snow cover duration is affected by global warming.
Petri Clusius, Metin Baykara, Carlton Xavier, Putian Zhou, Juniper Tyree, Benjamin Foreback, Mikko Äijälä, Frans Graeffe, Tuukka Petäjä, Markku Kulmala, Pauli Paasonen, Paul I. Palmer, and Michael Boy
EGUsphere, https://doi.org/10.5194/egusphere-2025-39, https://doi.org/10.5194/egusphere-2025-39, 2025
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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Cloud condensation nuclei are necessary to form clouds, and their size distribution affects cloud properties and therefore Earth’s energy budget. This study modelled the origins of cloud condensation nuclei at SMEAR II, Hyytiälä, Finland, and found that primary emissions and new particle formation separately contribute to more than half of the condensation nuclei, but they suppress each other, leading to current concentrations. Largest condensation nuclei originated mostly from emissions.
Jacob A. Nelson, Sophia Walther, Fabian Gans, Basil Kraft, Ulrich Weber, Kimberly Novick, Nina Buchmann, Mirco Migliavacca, Georg Wohlfahrt, Ladislav Šigut, Andreas Ibrom, Dario Papale, Mathias Göckede, Gregory Duveiller, Alexander Knohl, Lukas Hörtnagl, Russell L. Scott, Jiří Dušek, Weijie Zhang, Zayd Mahmoud Hamdi, Markus Reichstein, Sergio Aranda-Barranco, Jonas Ardö, Maarten Op de Beeck, Dave Billesbach, David Bowling, Rosvel Bracho, Christian Brümmer, Gustau Camps-Valls, Shiping Chen, Jamie Rose Cleverly, Ankur Desai, Gang Dong, Tarek S. El-Madany, Eugenie Susanne Euskirchen, Iris Feigenwinter, Marta Galvagno, Giacomo A. Gerosa, Bert Gielen, Ignacio Goded, Sarah Goslee, Christopher Michael Gough, Bernard Heinesch, Kazuhito Ichii, Marcin Antoni Jackowicz-Korczynski, Anne Klosterhalfen, Sara Knox, Hideki Kobayashi, Kukka-Maaria Kohonen, Mika Korkiakoski, Ivan Mammarella, Mana Gharun, Riccardo Marzuoli, Roser Matamala, Stefan Metzger, Leonardo Montagnani, Giacomo Nicolini, Thomas O'Halloran, Jean-Marc Ourcival, Matthias Peichl, Elise Pendall, Borja Ruiz Reverter, Marilyn Roland, Simone Sabbatini, Torsten Sachs, Marius Schmidt, Christopher R. Schwalm, Ankit Shekhar, Richard Silberstein, Maria Lucia Silveira, Donatella Spano, Torbern Tagesson, Gianluca Tramontana, Carlo Trotta, Fabio Turco, Timo Vesala, Caroline Vincke, Domenico Vitale, Enrique R. Vivoni, Yi Wang, William Woodgate, Enrico A. Yepez, Junhui Zhang, Donatella Zona, and Martin Jung
Biogeosciences, 21, 5079–5115, https://doi.org/10.5194/bg-21-5079-2024, https://doi.org/10.5194/bg-21-5079-2024, 2024
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The movement of water, carbon, and energy from the Earth's surface to the atmosphere, or flux, is an important process to understand because it impacts our lives. Here, we outline a method called FLUXCOM-X to estimate global water and CO2 fluxes based on direct measurements from sites around the world. We go on to demonstrate how these new estimates of net CO2 uptake/loss, gross CO2 uptake, total water evaporation, and transpiration from plants compare to previous and independent estimates.
Matthew Boyer, Diego Aliaga, Lauriane L. J. Quéléver, Silvia Bucci, Hélène Angot, Lubna Dada, Benjamin Heutte, Lisa Beck, Marina Duetsch, Andreas Stohl, Ivo Beck, Tiia Laurila, Nina Sarnela, Roseline C. Thakur, Branka Miljevic, Markku Kulmala, Tuukka Petäjä, Mikko Sipilä, Julia Schmale, and Tuija Jokinen
Atmos. Chem. Phys., 24, 12595–12621, https://doi.org/10.5194/acp-24-12595-2024, https://doi.org/10.5194/acp-24-12595-2024, 2024
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We analyze the seasonal cycle and sources of gases that are relevant for the formation of aerosol particles in the central Arctic. Since theses gases can form new particles, they can influence Arctic climate. We show that the sources of these gases are associated with changes in the Arctic environment during the year, especially with respect to sea ice. Therefore, the concentration of these gases will likely change in the future as the Arctic continues to warm.
Sami D. Harni, Minna Aurela, Sanna Saarikoski, Jarkko V. Niemi, Harri Portin, Hanna Manninen, Ville Leinonen, Pasi Aalto, Phil K. Hopke, Tuukka Petäjä, Topi Rönkkö, and Hilkka Timonen
Atmos. Chem. Phys., 24, 12143–12160, https://doi.org/10.5194/acp-24-12143-2024, https://doi.org/10.5194/acp-24-12143-2024, 2024
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In this study, particle number size distribution data were used in a novel way in positive matrix factorization analysis to find aerosol source profiles in the area. Measurements were made in Helsinki at a street canyon and urban background sites between February 2015 and June 2019. Five different aerosol sources were identified. These sources underline the significance of traffic-related emissions in urban environments despite recent improvements in emission reduction technologies.
Sander Mirme, Rima Balbaaki, Hanna Elina Manninen, Paap Koemets, Eva Sommer, Birte Rörup, Yusheng Wu, Joao Almeida, Sebastian Ehrhart, Stefan Karl Weber, Joschka Pfeifer, Juha Kangasluoma, Markku Kulmala, and Jasper Kirkby
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-138, https://doi.org/10.5194/amt-2024-138, 2024
Revised manuscript under review for AMT
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The manuscript describes the design and performance of the Cluster Ion Counter (CIC, Airel OÜ), a device which simultaneously measures the number concentrations of positively- and negatively-charged ions and particles below 5 nm mobility diameter. The presented measurements and operational experience demonstrate that the CIC provides precise and robust long-term measurements of small ion concentrations of both polarities, with low noise, fast time response and excellent reliability.
Franziska Vogel, Michael P. Adams, Larissa Lacher, Polly B. Foster, Grace C. E. Porter, Barbara Bertozzi, Kristina Höhler, Julia Schneider, Tobias Schorr, Nsikanabasi S. Umo, Jens Nadolny, Zoé Brasseur, Paavo Heikkilä, Erik S. Thomson, Nicole Büttner, Martin I. Daily, Romy Fösig, Alexander D. Harrison, Jorma Keskinen, Ulrike Proske, Jonathan Duplissy, Markku Kulmala, Tuukka Petäjä, Ottmar Möhler, and Benjamin J. Murray
Atmos. Chem. Phys., 24, 11737–11757, https://doi.org/10.5194/acp-24-11737-2024, https://doi.org/10.5194/acp-24-11737-2024, 2024
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Primary ice formation in clouds strongly influences their properties; hence, it is important to understand the sources of ice-nucleating particles (INPs) and their variability. We present 2 months of INP measurements in a Finnish boreal forest using a new semi-autonomous INP counting device based on gas expansion. These results show strong variability in INP concentrations, and we present a case that the INPs we observe are, at least some of the time, of biological origin.
Markku Kulmala, Santeri Tuovinen, Sander Mirme, Paap Koemets, Lauri Ahonen, Yongchun Liu, Heikki Junninen, Tuukka Petäjä, and Veli-Matti Kerminen
Aerosol Research, 2, 291–301, https://doi.org/10.5194/ar-2-291-2024, https://doi.org/10.5194/ar-2-291-2024, 2024
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With the recently developed CIC (Cluster Ion Counter) instrument, we can observe dynamics of small air ions and intermediate air ions. Furthermore, we can observe condensation sink and formation and growth rates for intermediated ions.
Zoé Brasseur, Julia Schneider, Janne Lampilahti, Ville Vakkari, Victoria A. Sinclair, Christina J. Williamson, Carlton Xavier, Dmitri Moisseev, Markus Hartmann, Pyry Poutanen, Markus Lampimäki, Markku Kulmala, Tuukka Petäjä, Katrianne Lehtipalo, Erik S. Thomson, Kristina Höhler, Ottmar Möhler, and Jonathan Duplissy
Atmos. Chem. Phys., 24, 11305–11332, https://doi.org/10.5194/acp-24-11305-2024, https://doi.org/10.5194/acp-24-11305-2024, 2024
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Ice-nucleating particles (INPs) strongly influence the formation of clouds by initiating the formation of ice crystals. However, very little is known about the vertical distribution of INPs in the atmosphere. Here, we present aircraft measurements of INP concentrations above the Finnish boreal forest. Results show that near-surface INPs are efficiently transported and mixed within the boundary layer and occasionally reach the free troposphere.
Anam M. Khan, Olivia E. Clifton, Jesse O. Bash, Sam Bland, Nathan Booth, Philip Cheung, Lisa Emberson, Johannes Flemming, Erick Fredj, Stefano Galmarini, Laurens Ganzeveld, Orestis Gazetas, Ignacio Goded, Christian Hogrefe, Christopher D. Holmes, Laszlo Horvath, Vincent Huijnen, Qian Li, Paul A. Makar, Ivan Mammarella, Giovanni Manca, J. William Munger, Juan L. Perez-Camanyo, Jonathan Pleim, Limei Ran, Roberto San Jose, Donna Schwede, Sam J. Silva, Ralf Staebler, Shihan Sun, Amos P. K. Tai, Eran Tas, Timo Vesala, Tamas Weidinger, Zhiyong Wu, Leiming Zhang, and Paul C. Stoy
EGUsphere, https://doi.org/10.5194/egusphere-2024-3038, https://doi.org/10.5194/egusphere-2024-3038, 2024
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Vegetation removes tropospheric ozone through stomatal uptake, and accurately modeling the stomatal uptake of ozone is important for modeling dry deposition and air quality. We evaluated the stomatal component of ozone dry deposition modeled by atmospheric chemistry models at six sites. We find that models and observation-based estimates agree at times during the growing season at all sites, but some models overestimated the stomatal component during the dry summers at a seasonally dry site.
Jia Sun, Markus Hermann, Kay Weinhold, Maik Merkel, Wolfram Birmili, Yifan Yang, Thomas Tuch, Harald Flentje, Björn Briel, Ludwig Ries, Cedric Couret, Michael Elsasser, Ralf Sohmer, Klaus Wirtz, Frank Meinhardt, Maik Schütze, Olaf Bath, Bryan Hellack, Veli-Matti Kerminen, Markku Kulmala, Nan Ma, and Alfred Wiedensohler
Atmos. Chem. Phys., 24, 10667–10687, https://doi.org/10.5194/acp-24-10667-2024, https://doi.org/10.5194/acp-24-10667-2024, 2024
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We investigated the characteristics of new particle formation (NPF) for various environments from urban background to high Alpine and the impacts of NPF on cloud condensation nuclei and aerosol radiative forcing. NPF features differ between site categories, implying the crucial role of local environmental factors such as the degree of emissions and meteorological conditions. The results also underscore the importance of local environments when assessing the impact of NPF on climate in models.
Alex Rowell, James Brean, David C. S. Beddows, Tuukka Petäjä, Máté Vörösmarty, Imre Salma, Jarkko V. Niemi, Hanna E. Manninen, Dominik van Pinxteren, Thomas Tuch, Kay Weinhold, Zongbo Shi, and Roy M. Harrison
Atmos. Chem. Phys., 24, 9515–9531, https://doi.org/10.5194/acp-24-9515-2024, https://doi.org/10.5194/acp-24-9515-2024, 2024
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Different sources of airborne particles in the atmospheres of four European cities were distinguished by recognising their particle size distributions using a statistical procedure, positive matrix factorisation. The various sources responded differently to the changes in emissions associated with COVID-19 lockdowns, and the reasons are investigated. While traffic emissions generally decreased, particles formed from reactions of atmospheric gases decreased in some cities but increased in others.
Yusheng Zhang, Feixue Zheng, Zemin Feng, Chaofan Lian, Weigang Wang, Xiaolong Fan, Wei Ma, Zhuohui Lin, Chang Li, Gen Zhang, Chao Yan, Ying Zhang, Veli-Matti Kerminen, Federico Bianch, Tuukka Petäjä, Juha Kangasluoma, Markku Kulmala, and Yongchun Liu
Atmos. Chem. Phys., 24, 8569–8587, https://doi.org/10.5194/acp-24-8569-2024, https://doi.org/10.5194/acp-24-8569-2024, 2024
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The nitrous acid (HONO) budget was validated during a COVID-19 lockdown event. The main conclusions are (1) HONO concentrations showed a significant decrease from 0.97 to 0.53 ppb during lockdown; (2) vehicle emissions accounted for 53 % of nighttime sources, with the heterogeneous conversion of NO2 on ground surfaces more important than aerosol; and (3) the dominant daytime source shifted from the homogenous reaction between NO and OH (51 %) to nitrate photolysis (53 %) during lockdown.
Louise Akemi Kuana, Arlan Scortegagna Almeida, Emílio Graciliano Ferreira Mercuri, and Steffen Manfred Noe
Hydrol. Earth Syst. Sci., 28, 3367–3390, https://doi.org/10.5194/hess-28-3367-2024, https://doi.org/10.5194/hess-28-3367-2024, 2024
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The authors compared regionalization methods for river flow prediction in 126 catchments from the south of Brazil, a region with humid subtropical and hot temperate climate. The regionalization method based on physiographic–climatic similarity had the best performance for predicting daily and Q95 reference flow. We showed that basins without flow monitoring can have a good approximation of streamflow using machine learning and physiographic–climatic information as inputs.
Piaopiao Ke, Anna Lintunen, Pasi Kolari, Annalea Lohila, Santeri Tuovinen, Janne Lampilahti, Roseline Thakur, Maija Peltola, Otso Peräkylä, Tuomo Nieminen, Ekaterina Ezhova, Mari Pihlatie, Asta Laasonen, Markku Koskinen, Helena Rautakoski, Laura Heimsch, Tom Kokkonen, Aki Vähä, Ivan Mammarella, Steffen Noe, Jaana Bäck, Veli-Matti Kerminen, and Markku Kulmala
EGUsphere, https://doi.org/10.5194/egusphere-2024-1967, https://doi.org/10.5194/egusphere-2024-1967, 2024
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Our research explores diverse ecosystems’ role in climate cooling via the concept of CarbonSink+ Potential. We measured CO2 uptake and loaal aerosol production in forests, farms, peatlands, urban gardens, and coastal areas across Finland and Estonia. The long-term data reveal that while forests are vital regarding CarbonSink+ Potential, farms and urban gardens also play significant roles. These insights can help optimize management policy of natural resource to mitigate global warming.
Kim A. P. Faassen, Jordi Vilà-Guerau de Arellano, Raquel González-Armas, Bert G. Heusinkveld, Ivan Mammarella, Wouter Peters, and Ingrid T. Luijkx
Biogeosciences, 21, 3015–3039, https://doi.org/10.5194/bg-21-3015-2024, https://doi.org/10.5194/bg-21-3015-2024, 2024
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The ratio between atmospheric O2 and CO2 can be used to characterize the carbon balance at the surface. By combining a model and observations from the Hyytiälä forest (Finland), we show that using atmospheric O2 and CO2 measurements from a single height provides a weak constraint on the surface CO2 exchange because large-scale processes such as entrainment confound this signal. We therefore recommend always using multiple heights of O2 and CO2 measurements to study surface CO2 exchange.
Esko Karvinen, Leif Backman, Leena Järvi, and Liisa Kulmala
SOIL, 10, 381–406, https://doi.org/10.5194/soil-10-381-2024, https://doi.org/10.5194/soil-10-381-2024, 2024
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We measured and modelled soil respiration, a key part of the biogenic carbon cycle, in different urban green space types to assess its dynamics in urban areas. We discovered surprisingly similar soil respiration across the green space types despite differences in some of its drivers and that irrigation of green spaces notably elevates soil respiration. Our results encourage further research on the topic and especially on the role of irrigation in controlling urban soil respiration.
Max Gaber, Yanghui Kang, Guy Schurgers, and Trevor Keenan
Biogeosciences, 21, 2447–2472, https://doi.org/10.5194/bg-21-2447-2024, https://doi.org/10.5194/bg-21-2447-2024, 2024
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Gross primary productivity (GPP) describes the photosynthetic carbon assimilation, which plays a vital role in the carbon cycle. We can measure GPP locally, but producing larger and continuous estimates is challenging. Here, we present an approach to extrapolate GPP to a global scale using satellite imagery and automated machine learning. We benchmark different models and predictor variables and achieve an estimate that can capture 75 % of the variation in GPP.
Santeri Tuovinen, Janne Lampilahti, Veli-Matti Kerminen, and Markku Kulmala
Aerosol Research, 2, 93–105, https://doi.org/10.5194/ar-2-93-2024, https://doi.org/10.5194/ar-2-93-2024, 2024
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Atmospheric intermediate ions can be used to study atmospheric new particle formation (NPF). Here we aimed to find the optimal ion diameter for this purpose on a local scale. To fulfill our aim, we used ion size number distribution data from the SMEAR II measurement station, Hyytiälä, Finland. We found that concentrations of ions between 2.0–2.3 nm are the best suited for characterization of local intermediate ion formation and could be used to detect and evaluate the strength of local NPF.
Liine Heikkinen, Daniel G. Partridge, Sara Blichner, Wei Huang, Rahul Ranjan, Paul Bowen, Emanuele Tovazzi, Tuukka Petäjä, Claudia Mohr, and Ilona Riipinen
Atmos. Chem. Phys., 24, 5117–5147, https://doi.org/10.5194/acp-24-5117-2024, https://doi.org/10.5194/acp-24-5117-2024, 2024
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The organic vapor condensation with water vapor (co-condensation) in rising air below clouds is modeled in this work over the boreal forest because the forest air is rich in organic vapors. We show that the number of cloud droplets can increase by 20 % if considering co-condensation. The enhancements are even larger if the air contains many small, naturally produced aerosol particles. Such conditions are most frequently met in spring in the boreal forest.
Bjorn Stevens, Stefan Adami, Tariq Ali, Hartwig Anzt, Zafer Aslan, Sabine Attinger, Jaana Bäck, Johanna Baehr, Peter Bauer, Natacha Bernier, Bob Bishop, Hendryk Bockelmann, Sandrine Bony, Guy Brasseur, David N. Bresch, Sean Breyer, Gilbert Brunet, Pier Luigi Buttigieg, Junji Cao, Christelle Castet, Yafang Cheng, Ayantika Dey Choudhury, Deborah Coen, Susanne Crewell, Atish Dabholkar, Qing Dai, Francisco Doblas-Reyes, Dale Durran, Ayoub El Gaidi, Charlie Ewen, Eleftheria Exarchou, Veronika Eyring, Florencia Falkinhoff, David Farrell, Piers M. Forster, Ariane Frassoni, Claudia Frauen, Oliver Fuhrer, Shahzad Gani, Edwin Gerber, Debra Goldfarb, Jens Grieger, Nicolas Gruber, Wilco Hazeleger, Rolf Herken, Chris Hewitt, Torsten Hoefler, Huang-Hsiung Hsu, Daniela Jacob, Alexandra Jahn, Christian Jakob, Thomas Jung, Christopher Kadow, In-Sik Kang, Sarah Kang, Karthik Kashinath, Katharina Kleinen-von Königslöw, Daniel Klocke, Uta Kloenne, Milan Klöwer, Chihiro Kodama, Stefan Kollet, Tobias Kölling, Jenni Kontkanen, Steve Kopp, Michal Koran, Markku Kulmala, Hanna Lappalainen, Fakhria Latifi, Bryan Lawrence, June Yi Lee, Quentin Lejeun, Christian Lessig, Chao Li, Thomas Lippert, Jürg Luterbacher, Pekka Manninen, Jochem Marotzke, Satoshi Matsouoka, Charlotte Merchant, Peter Messmer, Gero Michel, Kristel Michielsen, Tomoki Miyakawa, Jens Müller, Ramsha Munir, Sandeep Narayanasetti, Ousmane Ndiaye, Carlos Nobre, Achim Oberg, Riko Oki, Tuba Özkan-Haller, Tim Palmer, Stan Posey, Andreas Prein, Odessa Primus, Mike Pritchard, Julie Pullen, Dian Putrasahan, Johannes Quaas, Krishnan Raghavan, Venkatachalam Ramaswamy, Markus Rapp, Florian Rauser, Markus Reichstein, Aromar Revi, Sonakshi Saluja, Masaki Satoh, Vera Schemann, Sebastian Schemm, Christina Schnadt Poberaj, Thomas Schulthess, Cath Senior, Jagadish Shukla, Manmeet Singh, Julia Slingo, Adam Sobel, Silvina Solman, Jenna Spitzer, Philip Stier, Thomas Stocker, Sarah Strock, Hang Su, Petteri Taalas, John Taylor, Susann Tegtmeier, Georg Teutsch, Adrian Tompkins, Uwe Ulbrich, Pier-Luigi Vidale, Chien-Ming Wu, Hao Xu, Najibullah Zaki, Laure Zanna, Tianjun Zhou, and Florian Ziemen
Earth Syst. Sci. Data, 16, 2113–2122, https://doi.org/10.5194/essd-16-2113-2024, https://doi.org/10.5194/essd-16-2113-2024, 2024
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To manage Earth in the Anthropocene, new tools, new institutions, and new forms of international cooperation will be required. Earth Virtualization Engines is proposed as an international federation of centers of excellence to empower all people to respond to the immense and urgent challenges posed by climate change.
Rostislav Kouznetsov, Risto Hänninen, Andreas Uppstu, Evgeny Kadantsev, Yalda Fatahi, Marje Prank, Dmitrii Kouznetsov, Steffen Manfred Noe, Heikki Junninen, and Mikhail Sofiev
Atmos. Chem. Phys., 24, 4675–4691, https://doi.org/10.5194/acp-24-4675-2024, https://doi.org/10.5194/acp-24-4675-2024, 2024
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By relying solely on publicly available media reports, we were able to infer the temporal evolution and the injection height for the Nord Stream gas leaks in September 2022. The inventory specifies locations, vertical distributions, and temporal evolution of the methane sources. The inventory can be used to simulate the event with atmospheric transport models. The inventory is supplemented with a set of observational data tailored to evaluate the results of the simulated atmospheric dispersion.
Tapio Elomaa, Krista Luoma, Sami Harni, Aki Virkkula, Hilkka Timonen, and Tuukka Petäjä
Aerosol Research Discuss., https://doi.org/10.5194/ar-2024-12, https://doi.org/10.5194/ar-2024-12, 2024
Revised manuscript accepted for AR
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Black Carbon (BC) is a pollutant from combustion that affects the climate and is harmful to health. We tested four different small BC sensors with a reference in Helsinki. The sensors compared well with the reference. As a sensor network they were able to capture differences in BC. Changes in temperature (T) and relative humidity (RH) caused error in the measurement. To reduce the effects of T and RH on BC sensors, more robust boxes should be developed or corrections should be applied.
Markku Kulmala, Diego Aliaga, Santeri Tuovinen, Runlong Cai, Heikki Junninen, Chao Yan, Federico Bianchi, Yafang Cheng, Aijun Ding, Douglas R. Worsnop, Tuukka Petäjä, Katrianne Lehtipalo, Pauli Paasonen, and Veli-Matti Kerminen
Aerosol Research, 2, 49–58, https://doi.org/10.5194/ar-2-49-2024, https://doi.org/10.5194/ar-2-49-2024, 2024
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Atmospheric new particle formation (NPF), together with secondary production of particulate matter in the atmosphere, dominates aerosol particle number concentrations and submicron particle mass loads in many environments globally. In this opinion paper, we describe the paradigm shift to understand NPF in a continuous way instead of using traditional binary event–non-event analysis.
Jian Zhao, Valter Mickwitz, Yuanyuan Luo, Ella Häkkinen, Frans Graeffe, Jiangyi Zhang, Hilkka Timonen, Manjula Canagaratna, Jordan E. Krechmer, Qi Zhang, Markku Kulmala, Juha Kangasluoma, Douglas Worsnop, and Mikael Ehn
Atmos. Meas. Tech., 17, 1527–1543, https://doi.org/10.5194/amt-17-1527-2024, https://doi.org/10.5194/amt-17-1527-2024, 2024
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Organic aerosol constitutes a significant portion of atmospheric fine particles but is less characterized due to its vast number of constituents. Recently, we developed a system for online measurements of particle-phase highly oxygenated organic molecules (HOMs). In this work, we systematically characterized the system, developed a new unit to enhance its performance, and demonstrated the essential role of thermograms in inferring volatility and quantifying HOMs in organic aerosols.
Shiyi Lai, Ximeng Qi, Xin Huang, Sijia Lou, Xuguang Chi, Liangduo Chen, Chong Liu, Yuliang Liu, Chao Yan, Mengmeng Li, Tengyu Liu, Wei Nie, Veli-Matti Kerminen, Tuukka Petäjä, Markku Kulmala, and Aijun Ding
Atmos. Chem. Phys., 24, 2535–2553, https://doi.org/10.5194/acp-24-2535-2024, https://doi.org/10.5194/acp-24-2535-2024, 2024
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By combining in situ measurements and chemical transport modeling, this study investigates new particle formation (NPF) on the southeastern Tibetan Plateau. We found that the NPF was driven by the presence of biogenic gases and the transport of anthropogenic precursors. The NPF was vertically heterogeneous and shaped by the vertical mixing. This study highlights the importance of anthropogenic–biogenic interactions and meteorological dynamics in NPF in this climate-sensitive region.
Jing Cai, Juha Sulo, Yifang Gu, Sebastian Holm, Runlong Cai, Steven Thomas, Almuth Neuberger, Fredrik Mattsson, Marco Paglione, Stefano Decesari, Matteo Rinaldi, Rujing Yin, Diego Aliaga, Wei Huang, Yuanyuan Li, Yvette Gramlich, Giancarlo Ciarelli, Lauriane Quéléver, Nina Sarnela, Katrianne Lehtipalo, Nora Zannoni, Cheng Wu, Wei Nie, Juha Kangasluoma, Claudia Mohr, Markku Kulmala, Qiaozhi Zha, Dominik Stolzenburg, and Federico Bianchi
Atmos. Chem. Phys., 24, 2423–2441, https://doi.org/10.5194/acp-24-2423-2024, https://doi.org/10.5194/acp-24-2423-2024, 2024
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By combining field measurements, simulations and recent chamber experiments, we investigate new particle formation (NPF) and growth in the Po Valley, where both haze and frequent NPF occur. Our results show that sulfuric acid, ammonia and amines are the dominant NPF precursors there. A high NPF rate and a lower condensation sink lead to a greater survival probability for newly formed particles, highlighting the importance of gas-to-particle conversion for aerosol concentrations.
Anton Rusanen, Anton Björklund, Manousos I. Manousakas, Jianhui Jiang, Markku T. Kulmala, Kai Puolamäki, and Kaspar R. Daellenbach
Atmos. Meas. Tech., 17, 1251–1277, https://doi.org/10.5194/amt-17-1251-2024, https://doi.org/10.5194/amt-17-1251-2024, 2024
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We present a Bayesian non-negative matrix factorization model that performs better on our test datasets than currently widely used models. Its advantages are better use of time information and providing a direct error estimation. We believe this could lead to better estimates of emission sources from measurements.
Justine Trémeau, Beñat Olascoaga, Leif Backman, Esko Karvinen, Henriikka Vekuri, and Liisa Kulmala
Biogeosciences, 21, 949–972, https://doi.org/10.5194/bg-21-949-2024, https://doi.org/10.5194/bg-21-949-2024, 2024
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We studied urban lawns and meadows in the Helsinki metropolitan area, Finland. We found that meadows are more resistant to drought events but that they do not increase carbon sequestration compared with lawns. Moreover, the transformation from lawns to meadows did not demonstrate any negative climate effects in terms of greenhouse gas emissions. Even though social and economic aspects also steer urban development, these results can guide planning to consider carbon-smart options.
Juha Sulo, Joonas Enroth, Aki Pajunoja, Joonas Vanhanen, Katrianne Lehtipalo, Tuukka Petäjä, and Markku Kulmala
Aerosol Research, 2, 13–20, https://doi.org/10.5194/ar-2-13-2024, https://doi.org/10.5194/ar-2-13-2024, 2024
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We present a novel version of an aerosol number size distribution instrument, showcasing its capability to measure particle number concentration and particle number size distribution between 1 and 12 nm. Our results show that the instrument agrees well with existing instrumentation and allows for both the accurate measurement of the smallest particles and overlap with more conventional aerosol number size distribution instruments.
Ying Zhang, Duzitian Li, Xu-Cheng He, Wei Nie, Chenjuan Deng, Runlong Cai, Yuliang Liu, Yishuo Guo, Chong Liu, Yiran Li, Liangduo Chen, Yuanyuan Li, Chenjie Hua, Tingyu Liu, Zongcheng Wang, Jiali Xie, Lei Wang, Tuukka Petäjä, Federico Bianchi, Ximeng Qi, Xuguang Chi, Pauli Paasonen, Yongchun Liu, Chao Yan, Jingkun Jiang, Aijun Ding, and Markku Kulmala
Atmos. Chem. Phys., 24, 1873–1893, https://doi.org/10.5194/acp-24-1873-2024, https://doi.org/10.5194/acp-24-1873-2024, 2024
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This study conducts a long-term observation of gaseous iodine oxoacids in two Chinese megacities, revealing their ubiquitous presence with peak concentrations (up to 0.1 pptv) in summer. Our analysis suggests a mix of terrestrial and marine sources for iodine. Additionally, iodic acid is identified as a notable contributor to sub-3 nm particle growth and particle survival probability.
Giancarlo Ciarelli, Sara Tahvonen, Arineh Cholakian, Manuel Bettineschi, Bruno Vitali, Tuukka Petäjä, and Federico Bianchi
Geosci. Model Dev., 17, 545–565, https://doi.org/10.5194/gmd-17-545-2024, https://doi.org/10.5194/gmd-17-545-2024, 2024
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The terrestrial ecosystem releases large quantities of biogenic gases in the Earth's Atmosphere. These gases can effectively be converted into so-called biogenic aerosol particles and, eventually, affect the Earth's climate. Climate prediction varies greatly depending on how these processes are represented in model simulations. In this study, we present a detailed model evaluation analysis aimed at understanding the main source of uncertainty in predicting the formation of biogenic aerosols.
Juan Andrés Casquero-Vera, Daniel Pérez-Ramírez, Hassan Lyamani, Fernando Rejano, Andrea Casans, Gloria Titos, Francisco José Olmo, Lubna Dada, Simo Hakala, Tareq Hussein, Katrianne Lehtipalo, Pauli Paasonen, Antti Hyvärinen, Noemí Pérez, Xavier Querol, Sergio Rodríguez, Nikos Kalivitis, Yenny González, Mansour A. Alghamdi, Veli-Matti Kerminen, Andrés Alastuey, Tuukka Petäjä, and Lucas Alados-Arboledas
Atmos. Chem. Phys., 23, 15795–15814, https://doi.org/10.5194/acp-23-15795-2023, https://doi.org/10.5194/acp-23-15795-2023, 2023
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Here we present the first study of the effect of mineral dust on the inhibition/promotion of new particle formation (NPF) events in different dust-influenced areas. Unexpectedly, we show that the occurrence of NPF events is highly frequent during mineral dust outbreaks, occurring even during extreme dust outbreaks. We also show that the occurrence of NPF events during mineral dust outbreaks significantly affects the potential cloud condensation nuclei budget.
Diego Aliaga, Santeri Tuovinen, Tinghan Zhang, Janne Lampilahti, Xinyang Li, Lauri Ahonen, Tom Kokkonen, Tuomo Nieminen, Simo Hakala, Pauli Paasonen, Federico Bianchi, Doug Worsnop, Veli-Matti Kerminen, and Markku Kulmala
Aerosol Research, 1, 81–92, https://doi.org/10.5194/ar-1-81-2023, https://doi.org/10.5194/ar-1-81-2023, 2023
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We introduce a novel method for evaluating days when small particles are formed in the atmosphere. Instead of the traditional binary division between event and non-event days, our method, known as "nano ranking analysis", provides a continuous, non-categorical metric for each day. By utilizing data from Hyytiälä, Finland, we show that our approach effectively quantifies these events. This innovative method paves the way for a deeper understanding of the factors influencing particle formation.
Markku Kulmala, Anna Lintunen, Hanna Lappalainen, Annele Virtanen, Chao Yan, Ekaterina Ezhova, Tuomo Nieminen, Ilona Riipinen, Risto Makkonen, Johanna Tamminen, Anu-Maija Sundström, Antti Arola, Armin Hansel, Kari Lehtinen, Timo Vesala, Tuukka Petäjä, Jaana Bäck, Tom Kokkonen, and Veli-Matti Kerminen
Atmos. Chem. Phys., 23, 14949–14971, https://doi.org/10.5194/acp-23-14949-2023, https://doi.org/10.5194/acp-23-14949-2023, 2023
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To be able to meet global grand challenges, we need comprehensive open data with proper metadata. In this opinion paper, we describe the SMEAR (Station for Measuring Earth surface – Atmosphere Relations) concept and include several examples (cases), such as new particle formation and growth, feedback loops and the effect of COVID-19, and what has been learned from these investigations. The future needs and the potential of comprehensive observations of the environment are summarized.
Putian Zhou, Zhengyao Lu, Jukka-Pekka Keskinen, Qiong Zhang, Juha Lento, Jianpu Bian, Twan van Noije, Philippe Le Sager, Veli-Matti Kerminen, Markku Kulmala, Michael Boy, and Risto Makkonen
Clim. Past, 19, 2445–2462, https://doi.org/10.5194/cp-19-2445-2023, https://doi.org/10.5194/cp-19-2445-2023, 2023
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A Green Sahara with enhanced rainfall and larger vegetation cover existed in northern Africa about 6000 years ago. Biosphere–atmosphere interactions are found to be critical to explaining this wet period. Based on modeled vegetation reconstruction data, we simulated dust emissions and aerosol formation, which are key factors in biosphere–atmosphere interactions. Our results also provide a benchmark of aerosol climatology for future paleo-climate simulation experiments.
Xiaoxiao Li, Yijing Chen, Yuyang Li, Runlong Cai, Yiran Li, Chenjuan Deng, Jin Wu, Chao Yan, Hairong Cheng, Yongchun Liu, Markku Kulmala, Jiming Hao, James N. Smith, and Jingkun Jiang
Atmos. Chem. Phys., 23, 14801–14812, https://doi.org/10.5194/acp-23-14801-2023, https://doi.org/10.5194/acp-23-14801-2023, 2023
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Near-continuous measurements show the composition, sources, and seasonal variations of ultrafine particles (UFPs) in urban Beijing. Vehicle and cooking emissions and new particle formation are the main sources of UFPs, and aqueous/heterogeneous processes increase UFP mode diameters. UFPs are the highest in winter due to the highest primary particle emission rates and new particle formation rates, and CHO fractions are the highest in summer due to the strongest photooxidation.
Joyson Ahongshangbam, Liisa Kulmala, Jesse Soininen, Yasmin Frühauf, Esko Karvinen, Yann Salmon, Anna Lintunen, Anni Karvonen, and Leena Järvi
Biogeosciences, 20, 4455–4475, https://doi.org/10.5194/bg-20-4455-2023, https://doi.org/10.5194/bg-20-4455-2023, 2023
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Urban vegetation is important for removing urban CO2 emissions and cooling. We studied the response of urban trees' functions (photosynthesis and transpiration) to a heatwave and drought at four urban green areas in the city of Helsinki. We found that tree water use was increased during heatwave and drought periods, but there was no change in the photosynthesis rates. The heat and drought conditions were severe at the local scale but were not excessive enough to restrict urban trees' functions.
Magdalena Okuljar, Olga Garmash, Miska Olin, Joni Kalliokoski, Hilkka Timonen, Jarkko V. Niemi, Pauli Paasonen, Jenni Kontkanen, Yanjun Zhang, Heidi Hellén, Heino Kuuluvainen, Minna Aurela, Hanna E. Manninen, Mikko Sipilä, Topi Rönkkö, Tuukka Petäjä, Markku Kulmala, Miikka Dal Maso, and Mikael Ehn
Atmos. Chem. Phys., 23, 12965–12983, https://doi.org/10.5194/acp-23-12965-2023, https://doi.org/10.5194/acp-23-12965-2023, 2023
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Highly oxygenated organic molecules (HOMs) form secondary organic aerosol that affects air quality and health. In this study, we demonstrate that in a moderately polluted city with abundant vegetation, the composition of HOMs is largely controlled by the effect of NOx on the biogenic volatile organic compound oxidation. Comparing the results from two nearby stations, we show that HOM composition and formation pathways can change considerably within small distances in urban environments.
Xu-Cheng He, Jiali Shen, Siddharth Iyer, Paxton Juuti, Jiangyi Zhang, Mrisha Koirala, Mikko M. Kytökari, Douglas R. Worsnop, Matti Rissanen, Markku Kulmala, Norbert M. Maier, Jyri Mikkilä, Mikko Sipilä, and Juha Kangasluoma
Atmos. Meas. Tech., 16, 4461–4487, https://doi.org/10.5194/amt-16-4461-2023, https://doi.org/10.5194/amt-16-4461-2023, 2023
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In this study, the upgraded multi-scheme chemical ionisation inlet 2 is presented. Sulfuric acid, hypoiodous acid, iodine, sulfur dioxide, and hydroperoxyl radicals are calibrated, and the improved ion optics allow us to detect sulfuric acid and iodine-containing molecules at as low as a few parts per quadrillion by volume. Additionally, we confirm the reliable detection of iodic acid using both the nitrate and bromide chemical ionisation methods under atmospherically relevant conditions.
Jean-Philippe Putaud, Enrico Pisoni, Alexander Mangold, Christoph Hueglin, Jean Sciare, Michael Pikridas, Chrysanthos Savvides, Jakub Ondracek, Saliou Mbengue, Alfred Wiedensohler, Kay Weinhold, Maik Merkel, Laurent Poulain, Dominik van Pinxteren, Hartmut Herrmann, Andreas Massling, Claus Nordstroem, Andrés Alastuey, Cristina Reche, Noemí Pérez, Sonia Castillo, Mar Sorribas, Jose Antonio Adame, Tuukka Petaja, Katrianne Lehtipalo, Jarkko Niemi, Véronique Riffault, Joel F. de Brito, Augustin Colette, Olivier Favez, Jean-Eudes Petit, Valérie Gros, Maria I. Gini, Stergios Vratolis, Konstantinos Eleftheriadis, Evangelia Diapouli, Hugo Denier van der Gon, Karl Espen Yttri, and Wenche Aas
Atmos. Chem. Phys., 23, 10145–10161, https://doi.org/10.5194/acp-23-10145-2023, https://doi.org/10.5194/acp-23-10145-2023, 2023
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Many European people are still exposed to levels of air pollution that can affect their health. COVID-19 lockdowns in 2020 were used to assess the impact of the reduction in human mobility on air pollution across Europe by comparing measurement data with values that would be expected if no lockdown had occurred. We show that lockdown measures did not lead to consistent decreases in the concentrations of fine particulate matter suspended in the air, and we investigate why.
Olivia E. Clifton, Donna Schwede, Christian Hogrefe, Jesse O. Bash, Sam Bland, Philip Cheung, Mhairi Coyle, Lisa Emberson, Johannes Flemming, Erick Fredj, Stefano Galmarini, Laurens Ganzeveld, Orestis Gazetas, Ignacio Goded, Christopher D. Holmes, László Horváth, Vincent Huijnen, Qian Li, Paul A. Makar, Ivan Mammarella, Giovanni Manca, J. William Munger, Juan L. Pérez-Camanyo, Jonathan Pleim, Limei Ran, Roberto San Jose, Sam J. Silva, Ralf Staebler, Shihan Sun, Amos P. K. Tai, Eran Tas, Timo Vesala, Tamás Weidinger, Zhiyong Wu, and Leiming Zhang
Atmos. Chem. Phys., 23, 9911–9961, https://doi.org/10.5194/acp-23-9911-2023, https://doi.org/10.5194/acp-23-9911-2023, 2023
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A primary sink of air pollutants is dry deposition. Dry deposition estimates differ across the models used to simulate atmospheric chemistry. Here, we introduce an effort to examine dry deposition schemes from atmospheric chemistry models. We provide our approach’s rationale, document the schemes, and describe datasets used to drive and evaluate the schemes. We also launch the analysis of results by evaluating against observations and identifying the processes leading to model–model differences.
Simo Hakala, Ville Vakkari, Heikki Lihavainen, Antti-Pekka Hyvärinen, Kimmo Neitola, Jenni Kontkanen, Veli-Matti Kerminen, Markku Kulmala, Tuukka Petäjä, Tareq Hussein, Mamdouh I. Khoder, Mansour A. Alghamdi, and Pauli Paasonen
Atmos. Chem. Phys., 23, 9287–9321, https://doi.org/10.5194/acp-23-9287-2023, https://doi.org/10.5194/acp-23-9287-2023, 2023
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Things are not always as they first seem in ambient aerosol measurements. Observations of decreasing particle sizes are often interpreted as resulting from particle evaporation. We show that such observations can counterintuitively be explained by particles that are constantly growing in size. This requires one to account for the previous movements of the observed air. Our explanation implies a larger number of larger particles, meaning more significant effects of aerosols on climate and health.
Alessandro Zanchetta, Linda M. J. Kooijmans, Steven van Heuven, Andrea Scifo, Hubertus A. Scheeren, Ivan Mammarella, Ute Karstens, Jin Ma, Maarten Krol, and Huilin Chen
Biogeosciences, 20, 3539–3553, https://doi.org/10.5194/bg-20-3539-2023, https://doi.org/10.5194/bg-20-3539-2023, 2023
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Carbonyl sulfide (COS) has been suggested as a tool to estimate carbon dioxide (CO2) uptake by plants during photosynthesis. However, understanding its sources and sinks is critical to preventing biases in this estimate. Combining observations and models, this study proves that regional sources occasionally influence the measurements at the 60 m tall Lutjewad tower (1 m a.s.l.; 53°24′ N, 6°21′ E) in the Netherlands. Moreover, it estimates nighttime COS fluxes to be −3.0 ± 2.6 pmol m−2 s−1.
Dimitri Castarède, Zoé Brasseur, Yusheng Wu, Zamin A. Kanji, Markus Hartmann, Lauri Ahonen, Merete Bilde, Markku Kulmala, Tuukka Petäjä, Jan B. C. Pettersson, Berko Sierau, Olaf Stetzer, Frank Stratmann, Birgitta Svenningsson, Erik Swietlicki, Quynh Thu Nguyen, Jonathan Duplissy, and Erik S. Thomson
Atmos. Meas. Tech., 16, 3881–3899, https://doi.org/10.5194/amt-16-3881-2023, https://doi.org/10.5194/amt-16-3881-2023, 2023
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Clouds play a key role in Earth’s climate by influencing the surface energy budget. Certain types of atmospheric aerosols, called ice-nucleating particles (INPs), induce the formation of ice in clouds and, thus, often initiate precipitation formation. The Portable Ice Nucleation Chamber 2 (PINCii) is a new instrument developed to study ice formation and to conduct ambient measurements of INPs, allowing us to investigate the sources and properties of the atmospheric aerosols that can act as INPs.
Sophie L. Haslett, David M. Bell, Varun Kumar, Jay G. Slowik, Dongyu S. Wang, Suneeti Mishra, Neeraj Rastogi, Atinderpal Singh, Dilip Ganguly, Joel Thornton, Feixue Zheng, Yuanyuan Li, Wei Nie, Yongchun Liu, Wei Ma, Chao Yan, Markku Kulmala, Kaspar R. Daellenbach, David Hadden, Urs Baltensperger, Andre S. H. Prevot, Sachchida N. Tripathi, and Claudia Mohr
Atmos. Chem. Phys., 23, 9023–9036, https://doi.org/10.5194/acp-23-9023-2023, https://doi.org/10.5194/acp-23-9023-2023, 2023
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In Delhi, some aspects of daytime and nighttime atmospheric chemistry are inverted, and parodoxically, vehicle emissions may be limiting other forms of particle production. This is because the nighttime emissions of nitrogen oxide (NO) by traffic and biomass burning prevent some chemical processes that would otherwise create even more particles and worsen the urban haze.
Yuyang Li, Jiewen Shen, Bin Zhao, Runlong Cai, Shuxiao Wang, Yang Gao, Manish Shrivastava, Da Gao, Jun Zheng, Markku Kulmala, and Jingkun Jiang
Atmos. Chem. Phys., 23, 8789–8804, https://doi.org/10.5194/acp-23-8789-2023, https://doi.org/10.5194/acp-23-8789-2023, 2023
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We set up a new parameterization for 1.4 nm particle formation rates from sulfuric acid–dimethylamine (SA–DMA) nucleation, fully including the effects of coagulation scavenging and cluster stability. Incorporating the new parameterization into 3-D chemical transport models, we achieved better consistencies between simulation results and observation data. This new parameterization provides new insights into atmospheric nucleation simulations and its effects on atmospheric pollution or health.
Guangdong Niu, Ximeng Qi, Liangduo Chen, Lian Xue, Shiyi Lai, Xin Huang, Jiaping Wang, Xuguang Chi, Wei Nie, Veli-Matti Kerminen, Tuukka Petäjä, Markku Kulmala, and Aijun Ding
Atmos. Chem. Phys., 23, 7521–7534, https://doi.org/10.5194/acp-23-7521-2023, https://doi.org/10.5194/acp-23-7521-2023, 2023
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The reported below-cloud wet-scavenging coefficients (BWSCs) are much higher than theoretical data, but the reason remains unclear. Based on long-term observation, we find that air mass changing during rainfall events causes the overestimation of BWSCs. Thus, the discrepancy in BWSCs between observation and theory is not as large as currently believed. To obtain reasonable BWSCs and parameterizations from field observations, the effect of air mass changes needs to be considered.
Jonas Elm, Aladár Czitrovszky, Andreas Held, Annele Virtanen, Astrid Kiendler-Scharr, Benjamin J. Murray, Daniel McCluskey, Daniele Contini, David Broday, Eirini Goudeli, Hilkka Timonen, Joan Rosell-Llompart, Jose L. Castillo, Evangelia Diapouli, Mar Viana, Maria E. Messing, Markku Kulmala, Naděžda Zíková, and Sebastian H. Schmitt
Aerosol Research, 1, 13–16, https://doi.org/10.5194/ar-1-13-2023, https://doi.org/10.5194/ar-1-13-2023, 2023
Santeri Tuovinen, Janne Lampilahti, Veli-Matti Kerminen, and Markku Kulmala
EGUsphere, https://doi.org/10.5194/egusphere-2023-1108, https://doi.org/10.5194/egusphere-2023-1108, 2023
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Atmospheric ions can be used to characterize and detect atmospheric new particle formation. In this study we aimed to find the optimal ion diameter for this purpose within a local scale. To fulfill our aim, we used ion size number distribution data from SMEAR II measurement station, Hyytiälä, Finland. We found that negative ions between 2.0–2.3 nm are the best suited for characterization of local NPF, with minimized influence of transported ions.
Chenxi Li, Yuyang Li, Xiaoxiao Li, Runlong Cai, Yaxin Fan, Xiaohui Qiao, Rujing Yin, Chao Yan, Yishuo Guo, Yongchun Liu, Jun Zheng, Veli-Matti Kerminen, Markku Kulmala, Huayun Xiao, and Jingkun Jiang
Atmos. Chem. Phys., 23, 6879–6896, https://doi.org/10.5194/acp-23-6879-2023, https://doi.org/10.5194/acp-23-6879-2023, 2023
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New particle formation and growth in polluted environments are not fully understood despite intensive research. We applied a cluster dynamics–multicomponent sectional model to simulate the new particle formation events observed in Beijing, China. The simulation approximately captures how the events evolve. Further diagnosis shows that the oxygenated organic molecules may have been under-detected, and modulating their abundance leads to significantly improved simulation–observation agreement.
Joschka Pfeifer, Naser G. A. Mahfouz, Benjamin C. Schulze, Serge Mathot, Dominik Stolzenburg, Rima Baalbaki, Zoé Brasseur, Lucia Caudillo, Lubna Dada, Manuel Granzin, Xu-Cheng He, Houssni Lamkaddam, Brandon Lopez, Vladimir Makhmutov, Ruby Marten, Bernhard Mentler, Tatjana Müller, Antti Onnela, Maxim Philippov, Ana A. Piedehierro, Birte Rörup, Meredith Schervish, Ping Tian, Nsikanabasi S. Umo, Dongyu S. Wang, Mingyi Wang, Stefan K. Weber, André Welti, Yusheng Wu, Marcel Zauner-Wieczorek, Antonio Amorim, Imad El Haddad, Markku Kulmala, Katrianne Lehtipalo, Tuukka Petäjä, António Tomé, Sander Mirme, Hanna E. Manninen, Neil M. Donahue, Richard C. Flagan, Andreas Kürten, Joachim Curtius, and Jasper Kirkby
Atmos. Chem. Phys., 23, 6703–6718, https://doi.org/10.5194/acp-23-6703-2023, https://doi.org/10.5194/acp-23-6703-2023, 2023
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Attachment rate coefficients between ions and charged aerosol particles determine their lifetimes and may also influence cloud dynamics and aerosol processing. Here we present novel experiments that measure ion–aerosol attachment rate coefficients for multiply charged aerosol particles under atmospheric conditions in the CERN CLOUD chamber. Our results provide experimental discrimination between various theoretical models.
Yishuo Guo, Chenjuan Deng, Aino Ovaska, Feixue Zheng, Chenjie Hua, Junlei Zhan, Yiran Li, Jin Wu, Zongcheng Wang, Jiali Xie, Ying Zhang, Tingyu Liu, Yusheng Zhang, Boying Song, Wei Ma, Yongchun Liu, Chao Yan, Jingkun Jiang, Veli-Matti Kerminen, Men Xia, Tuomo Nieminen, Wei Du, Tom Kokkonen, and Markku Kulmala
Atmos. Chem. Phys., 23, 6663–6690, https://doi.org/10.5194/acp-23-6663-2023, https://doi.org/10.5194/acp-23-6663-2023, 2023
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Using the comprehensive datasets, we investigated the long-term variations of air pollutants during winter in Beijing from 2019 to 2022 and analyzed the characteristics of atmospheric pollution cocktail during different short-term special events (e.g., Beijing Winter Olympics, COVID lockdown and Chinese New Year) associated with substantial emission reductions. Our results are useful in planning more targeted and sustainable long-term pollution control plans.
Lucía Caudillo, Mihnea Surdu, Brandon Lopez, Mingyi Wang, Markus Thoma, Steffen Bräkling, Angela Buchholz, Mario Simon, Andrea C. Wagner, Tatjana Müller, Manuel Granzin, Martin Heinritzi, Antonio Amorim, David M. Bell, Zoé Brasseur, Lubna Dada, Jonathan Duplissy, Henning Finkenzeller, Xu-Cheng He, Houssni Lamkaddam, Naser G. A. Mahfouz, Vladimir Makhmutov, Hanna E. Manninen, Guillaume Marie, Ruby Marten, Roy L. Mauldin, Bernhard Mentler, Antti Onnela, Tuukka Petäjä, Joschka Pfeifer, Maxim Philippov, Ana A. Piedehierro, Birte Rörup, Wiebke Scholz, Jiali Shen, Dominik Stolzenburg, Christian Tauber, Ping Tian, António Tomé, Nsikanabasi Silas Umo, Dongyu S. Wang, Yonghong Wang, Stefan K. Weber, André Welti, Marcel Zauner-Wieczorek, Urs Baltensperger, Richard C. Flagan, Armin Hansel, Jasper Kirkby, Markku Kulmala, Katrianne Lehtipalo, Douglas R. Worsnop, Imad El Haddad, Neil M. Donahue, Alexander L. Vogel, Andreas Kürten, and Joachim Curtius
Atmos. Chem. Phys., 23, 6613–6631, https://doi.org/10.5194/acp-23-6613-2023, https://doi.org/10.5194/acp-23-6613-2023, 2023
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In this study, we present an intercomparison of four different techniques for measuring the chemical composition of nanoparticles. The intercomparison was performed based on the observed chemical composition, calculated volatility, and analysis of the thermograms. We found that the methods generally agree on the most important compounds that are found in the nanoparticles. However, they do see different parts of the organic spectrum. We suggest potential explanations for these differences.
Anton Rusanen, Kristo Hõrrak, Lauri R. Ahonen, Tuomo Nieminen, Pasi P. Aalto, Pasi Kolari, Markku Kulmala, Tuukka Petäjä, and Heikki Junninen
Atmos. Meas. Tech., 16, 2781–2793, https://doi.org/10.5194/amt-16-2781-2023, https://doi.org/10.5194/amt-16-2781-2023, 2023
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We present a framework for setting up SMEAR (Station for Measuring Ecosystem–Atmosphere Relations) type measurement station data flows. This framework, called SMEARcore, consists of modular open-source software components that can be chosen to suit various station configurations. The benefits of using this framework are automation of routine operations and real-time monitoring of measurement results.
Eka Dian Pusfitasari, Jose Ruiz-Jimenez, Aleksi Tiusanen, Markus Suuronen, Jesse Haataja, Yusheng Wu, Juha Kangasluoma, Krista Luoma, Tuukka Petäjä, Matti Jussila, Kari Hartonen, and Marja-Liisa Riekkola
Atmos. Chem. Phys., 23, 5885–5904, https://doi.org/10.5194/acp-23-5885-2023, https://doi.org/10.5194/acp-23-5885-2023, 2023
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A miniaturized air-sampling drone system was successfully applied for the collection of volatile organic compounds (VOCs) and for the measurement of black carbon (BC) and total particle number concentrations in atmospheric air. Here we report, for the first time, the vertical profiles of BC and aerosol number concentrations above the boreal forest in Hyytiälä (Finland) at high altitudes close to the boundary layer in autumn 2021. VOC composition with its distribution was studied as well.
Dominik Stolzenburg, Tiia Laurila, Pasi Aalto, Joonas Vanhanen, Tuukka Petäjä, and Juha Kangasluoma
Atmos. Meas. Tech., 16, 2471–2483, https://doi.org/10.5194/amt-16-2471-2023, https://doi.org/10.5194/amt-16-2471-2023, 2023
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Size-distribution measurements of ultrafine particles are of special interest as they can be used to estimate the atmospheric significance of new particle formation, a process which is thought to influence the global climate. Here we show that improved counting statistics in size-distribution measurements through the usage of higher sampling flows can significantly reduce the uncertainties in such calculations.
Rujing Yin, Xiaoxiao Li, Chao Yan, Runlong Cai, Ying Zhou, Juha Kangasluoma, Nina Sarnela, Janne Lampilahti, Tuukka Petäjä, Veli-Matti Kerminen, Federico Bianchi, Markku Kulmala, and Jingkun Jiang
Atmos. Chem. Phys., 23, 5279–5296, https://doi.org/10.5194/acp-23-5279-2023, https://doi.org/10.5194/acp-23-5279-2023, 2023
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Atmospheric cluster ions are important constituents in the atmosphere. However, the quantitative research on their compositions is still limited, especially in urban environments. Here we demonstrate the feasibility of an in situ quantification method of cluster ions measured by a high-resolution mass spectrometer and reveal their governing factors, sources, and sinks in urban Beijing through quantitative analysis of cluster ions, reagent ions, neutral molecules, and condensation sink.
Qi Guan, Jing Tang, Lian Feng, Stefan Olin, and Guy Schurgers
Biogeosciences, 20, 1635–1648, https://doi.org/10.5194/bg-20-1635-2023, https://doi.org/10.5194/bg-20-1635-2023, 2023
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Understanding terrestrial sources of nitrogen is vital to examine lake eutrophication changes. Combining process-based ecosystem modeling and satellite observations, we found that land-leached nitrogen in the Yangtze Plain significantly increased from 1979 to 2018, and terrestrial nutrient sources were positively correlated with eutrophication trends observed in most lakes, demonstrating the necessity of sustainable nitrogen management to control eutrophication.
Qiaozhi Zha, Wei Huang, Diego Aliaga, Otso Peräkylä, Liine Heikkinen, Alkuin Maximilian Koenig, Cheng Wu, Joonas Enroth, Yvette Gramlich, Jing Cai, Samara Carbone, Armin Hansel, Tuukka Petäjä, Markku Kulmala, Douglas Worsnop, Victoria Sinclair, Radovan Krejci, Marcos Andrade, Claudia Mohr, and Federico Bianchi
Atmos. Chem. Phys., 23, 4559–4576, https://doi.org/10.5194/acp-23-4559-2023, https://doi.org/10.5194/acp-23-4559-2023, 2023
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We investigate the chemical composition of atmospheric cluster ions from January to May 2018 at the high-altitude research station Chacaltaya (5240 m a.s.l.) in the Bolivian Andes. With state-of-the-art mass spectrometers and air mass history analysis, the measured cluster ions exhibited distinct diurnal and seasonal patterns, some of which contributed to new particle formation. Our study will improve the understanding of atmospheric ions and their role in high-altitude new particle formation.
Meri Räty, Larisa Sogacheva, Helmi-Marja Keskinen, Veli-Matti Kerminen, Tuomo Nieminen, Tuukka Petäjä, Ekaterina Ezhova, and Markku Kulmala
Atmos. Chem. Phys., 23, 3779–3798, https://doi.org/10.5194/acp-23-3779-2023, https://doi.org/10.5194/acp-23-3779-2023, 2023
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We utilised back trajectories to identify the source region of air masses arriving in Hyytiälä, Finland, and their travel time over forests. Combined with atmospheric observations, they revealed how air mass transport over the Fennoscandian boreal forest during the growing season produced an accumulation of cloud condensation nuclei and humidity, promoting cloudiness and precipitation. By 55 h of transport, air masses appeared to reach a balanced state with the forest environment.
Jing Cai, Kaspar R. Daellenbach, Cheng Wu, Yan Zheng, Feixue Zheng, Wei Du, Sophie L. Haslett, Qi Chen, Markku Kulmala, and Claudia Mohr
Atmos. Meas. Tech., 16, 1147–1165, https://doi.org/10.5194/amt-16-1147-2023, https://doi.org/10.5194/amt-16-1147-2023, 2023
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We introduce the offline application of FIGAERO-CIMS by analyzing Teflon and quartz filter samples that were collected at a typical urban site in Beijing with the deposition time varying from 30 min to 24 h. This method provides a feasible, simple, and quantitative way to investigate the molecular composition and volatility of OA compounds by using FIGAERO-CIMS to analyze offline samples.
Matti Kämäräinen, Juha-Pekka Tuovinen, Markku Kulmala, Ivan Mammarella, Juha Aalto, Henriikka Vekuri, Annalea Lohila, and Anna Lintunen
Biogeosciences, 20, 897–909, https://doi.org/10.5194/bg-20-897-2023, https://doi.org/10.5194/bg-20-897-2023, 2023
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In this study, we introduce a new method for modeling the exchange of carbon between the atmosphere and a study site located in a boreal forest in southern Finland. Our method yields more accurate results than previous approaches in this context. Accurately estimating carbon exchange is crucial for gaining a better understanding of the role of forests in regulating atmospheric carbon and addressing climate change.
Lejish Vettikkat, Pasi Miettinen, Angela Buchholz, Pekka Rantala, Hao Yu, Simon Schallhart, Tuukka Petäjä, Roger Seco, Elisa Männistö, Markku Kulmala, Eeva-Stiina Tuittila, Alex B. Guenther, and Siegfried Schobesberger
Atmos. Chem. Phys., 23, 2683–2698, https://doi.org/10.5194/acp-23-2683-2023, https://doi.org/10.5194/acp-23-2683-2023, 2023
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Wetlands cover a substantial fraction of the land mass in the northern latitudes, from northern Europe to Siberia and Canada. Yet, their isoprene and terpene emissions remain understudied. Here, we used a state-of-the-art measurement technique to quantify ecosystem-scale emissions from a boreal wetland during an unusually warm spring/summer. We found that the emissions from this wetland were (a) higher and (b) even more strongly dependent on temperature than commonly thought.
Konstantinos Matthaios Doulgeris, Ville Vakkari, Ewan J. O'Connor, Veli-Matti Kerminen, Heikki Lihavainen, and David Brus
Atmos. Chem. Phys., 23, 2483–2498, https://doi.org/10.5194/acp-23-2483-2023, https://doi.org/10.5194/acp-23-2483-2023, 2023
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We investigated how different long-range-transported air masses can affect the microphysical properties of low-level clouds in a clean subarctic environment. A connection was revealed. Higher values of cloud droplet number concentrations were related to continental air masses, whereas the lowest values of number concentrations were related to marine air masses. These were characterized by larger cloud droplets. Clouds in all regions were sensitive to increases in cloud number concentration.
Kim A. P. Faassen, Linh N. T. Nguyen, Eadin R. Broekema, Bert A. M. Kers, Ivan Mammarella, Timo Vesala, Penelope A. Pickers, Andrew C. Manning, Jordi Vilà-Guerau de Arellano, Harro A. J. Meijer, Wouter Peters, and Ingrid T. Luijkx
Atmos. Chem. Phys., 23, 851–876, https://doi.org/10.5194/acp-23-851-2023, https://doi.org/10.5194/acp-23-851-2023, 2023
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The exchange ratio (ER) between atmospheric O2 and CO2 provides a useful tracer for separately estimating photosynthesis and respiration processes in the forest carbon balance. This is highly relevant to better understand the expected biosphere sink, which determines future atmospheric CO2 levels. We therefore measured O2, CO2, and their ER above a boreal forest in Finland and investigated their diurnal behaviour for a representative day, and we show the most suitable way to determine the ER.
Wiebke Scholz, Jiali Shen, Diego Aliaga, Cheng Wu, Samara Carbone, Isabel Moreno, Qiaozhi Zha, Wei Huang, Liine Heikkinen, Jean Luc Jaffrezo, Gaelle Uzu, Eva Partoll, Markus Leiminger, Fernando Velarde, Paolo Laj, Patrick Ginot, Paolo Artaxo, Alfred Wiedensohler, Markku Kulmala, Claudia Mohr, Marcos Andrade, Victoria Sinclair, Federico Bianchi, and Armin Hansel
Atmos. Chem. Phys., 23, 895–920, https://doi.org/10.5194/acp-23-895-2023, https://doi.org/10.5194/acp-23-895-2023, 2023
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Dimethyl sulfide (DMS), emitted from the ocean, is the most abundant biogenic sulfur emission into the atmosphere. OH radicals, among others, can oxidize DMS to sulfuric and methanesulfonic acid, which are relevant for aerosol formation. We quantified DMS and nearly all DMS oxidation products with novel mass spectrometric instruments for gas and particle phase at the high mountain station Chacaltaya (5240 m a.s.l.) in the Bolivian Andes in free tropospheric air after long-range transport.
Matthew Boyer, Diego Aliaga, Jakob Boyd Pernov, Hélène Angot, Lauriane L. J. Quéléver, Lubna Dada, Benjamin Heutte, Manuel Dall'Osto, David C. S. Beddows, Zoé Brasseur, Ivo Beck, Silvia Bucci, Marina Duetsch, Andreas Stohl, Tiia Laurila, Eija Asmi, Andreas Massling, Daniel Charles Thomas, Jakob Klenø Nøjgaard, Tak Chan, Sangeeta Sharma, Peter Tunved, Radovan Krejci, Hans Christen Hansson, Federico Bianchi, Katrianne Lehtipalo, Alfred Wiedensohler, Kay Weinhold, Markku Kulmala, Tuukka Petäjä, Mikko Sipilä, Julia Schmale, and Tuija Jokinen
Atmos. Chem. Phys., 23, 389–415, https://doi.org/10.5194/acp-23-389-2023, https://doi.org/10.5194/acp-23-389-2023, 2023
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The Arctic is a unique environment that is warming faster than other locations on Earth. We evaluate measurements of aerosol particles, which can influence climate, over the central Arctic Ocean for a full year and compare the data to land-based measurement stations across the Arctic. Our measurements show that the central Arctic has similarities to but also distinct differences from the stations further south. We note that this may change as the Arctic warms and sea ice continues to decline.
Mykhailo Savenets, Larysa Pysarenko, Svitlana Krakovska, Alexander Mahura, and Tuukka Petäjä
Atmos. Chem. Phys., 22, 15777–15791, https://doi.org/10.5194/acp-22-15777-2022, https://doi.org/10.5194/acp-22-15777-2022, 2022
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The paper explores the spatio-temporal variability of black carbon during a wildfire in August 2010, with a focus on Ukraine. As a research tool, the seamless Enviro-HIRLAM modelling system is used for investigating the atmospheric transport of aerosol particles emitted by wildfires from remote and local sources. The results of this study improve our understanding of the physical and chemical processes and the interactions of aerosols in the atmosphere.
Juha Sulo, Janne Lampilahti, Xuemeng Chen, Jenni Kontkanen, Tuomo Nieminen, Veli-Matti Kerminen, Tuukka Petäjä, Markku Kulmala, and Katrianne Lehtipalo
Atmos. Chem. Phys., 22, 15223–15242, https://doi.org/10.5194/acp-22-15223-2022, https://doi.org/10.5194/acp-22-15223-2022, 2022
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We measured atmospheric ion concentrations continuously in a boreal forest between 2005 and 2021 and observed an increasing interannual trend. The increase in cluster ion concentrations can be largely explained by an overall decreasing level of anthropogenic aerosols in the boreal forest. This suggests that the role of ions in atmospheric new particle formation may be more important in the future.
Santeri Tuovinen, Runlong Cai, Veli-Matti Kerminen, Jingkun Jiang, Chao Yan, Markku Kulmala, and Jenni Kontkanen
Atmos. Chem. Phys., 22, 15071–15091, https://doi.org/10.5194/acp-22-15071-2022, https://doi.org/10.5194/acp-22-15071-2022, 2022
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We compare observed survival probabilities of atmospheric particles from Beijing, China, with survival probabilities based on analytical formulae and model simulations. We find observed survival probabilities under polluted conditions at smaller sizes to be higher, while at larger sizes they are lower than or similar to theoretical survival probabilities. Uncertainties in condensation sink and growth rate are unlikely to explain higher-than-predicted survival probabilities at smaller sizes.
Matti Räsänen, Mika Aurela, Ville Vakkari, Johan P. Beukes, Juha-Pekka Tuovinen, Pieter G. Van Zyl, Miroslav Josipovic, Stefan J. Siebert, Tuomas Laurila, Markku Kulmala, Lauri Laakso, Janne Rinne, Ram Oren, and Gabriel Katul
Hydrol. Earth Syst. Sci., 26, 5773–5791, https://doi.org/10.5194/hess-26-5773-2022, https://doi.org/10.5194/hess-26-5773-2022, 2022
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The productivity of semiarid grazed grasslands is linked to the variation in rainfall and transpiration. By combining carbon dioxide and water flux measurements, we show that the annual transpiration is nearly constant during wet years while grasses react quickly to dry spells and drought, which reduce transpiration. The planning of annual grazing strategies could consider the early-season rainfall frequency that was linked to the portion of annual transpiration.
Runlong Cai, Chenjuan Deng, Dominik Stolzenburg, Chenxi Li, Junchen Guo, Veli-Matti Kerminen, Jingkun Jiang, Markku Kulmala, and Juha Kangasluoma
Atmos. Chem. Phys., 22, 14571–14587, https://doi.org/10.5194/acp-22-14571-2022, https://doi.org/10.5194/acp-22-14571-2022, 2022
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The survival probability of new particles is the key parameter governing their influences on the atmosphere and climate, yet the knowledge of particle survival in the atmosphere is rather limited. We propose methods to compute the size-resolved particle survival probability and validate them using simulations and measurements from diverse environments. Using these methods, we could explain particle survival from the cluster size to the cloud condensation nuclei size.
Chenjuan Deng, Yiran Li, Chao Yan, Jin Wu, Runlong Cai, Dongbin Wang, Yongchun Liu, Juha Kangasluoma, Veli-Matti Kerminen, Markku Kulmala, and Jingkun Jiang
Atmos. Chem. Phys., 22, 13569–13580, https://doi.org/10.5194/acp-22-13569-2022, https://doi.org/10.5194/acp-22-13569-2022, 2022
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The size distributions of urban atmospheric particles convey important information on their origins and impacts. This study investigates the characteristics of typical particle size distributions and key gaseous precursors in the long term in urban Beijing. A fitting function is proposed to represent and help interpret size distribution including particles and gaseous precursors. In addition to NPF (new particle formation) as the major source, vehicles can emit sub-3 nm particles as well
Loïc Gonzalez Carracedo, Katrianne Lehtipalo, Lauri R. Ahonen, Nina Sarnela, Sebastian Holm, Juha Kangasluoma, Markku Kulmala, Paul M. Winkler, and Dominik Stolzenburg
Atmos. Chem. Phys., 22, 13153–13166, https://doi.org/10.5194/acp-22-13153-2022, https://doi.org/10.5194/acp-22-13153-2022, 2022
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Fast nanoparticle growth is essential for the survival of new aerosol particles in the atmosphere and hence their contribution to the climate. We show that using naturally charged ions for growth calculations can cause a significant error. During the diurnal cycle, the importance of ion-induced and neutral nucleation varies, causing the ion population to have a slower measurable apparent growth. Results suggest that data from ion spectrometers need to be considered with great care below 3 nm.
Ville Leinonen, Harri Kokkola, Taina Yli-Juuti, Tero Mielonen, Thomas Kühn, Tuomo Nieminen, Simo Heikkinen, Tuuli Miinalainen, Tommi Bergman, Ken Carslaw, Stefano Decesari, Markus Fiebig, Tareq Hussein, Niku Kivekäs, Radovan Krejci, Markku Kulmala, Ari Leskinen, Andreas Massling, Nikos Mihalopoulos, Jane P. Mulcahy, Steffen M. Noe, Twan van Noije, Fiona M. O'Connor, Colin O'Dowd, Dirk Olivie, Jakob B. Pernov, Tuukka Petäjä, Øyvind Seland, Michael Schulz, Catherine E. Scott, Henrik Skov, Erik Swietlicki, Thomas Tuch, Alfred Wiedensohler, Annele Virtanen, and Santtu Mikkonen
Atmos. Chem. Phys., 22, 12873–12905, https://doi.org/10.5194/acp-22-12873-2022, https://doi.org/10.5194/acp-22-12873-2022, 2022
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We provide the first extensive comparison of detailed aerosol size distribution trends between in situ observations from Europe and five different earth system models. We investigated aerosol modes (nucleation, Aitken, and accumulation) separately and were able to show the differences between measured and modeled trends and especially their seasonal patterns. The differences in model results are likely due to complex effects of several processes instead of certain specific model features.
Chao Yan, Yicheng Shen, Dominik Stolzenburg, Lubna Dada, Ximeng Qi, Simo Hakala, Anu-Maija Sundström, Yishuo Guo, Antti Lipponen, Tom V. Kokkonen, Jenni Kontkanen, Runlong Cai, Jing Cai, Tommy Chan, Liangduo Chen, Biwu Chu, Chenjuan Deng, Wei Du, Xiaolong Fan, Xu-Cheng He, Juha Kangasluoma, Joni Kujansuu, Mona Kurppa, Chang Li, Yiran Li, Zhuohui Lin, Yiliang Liu, Yuliang Liu, Yiqun Lu, Wei Nie, Jouni Pulliainen, Xiaohui Qiao, Yonghong Wang, Yifan Wen, Ye Wu, Gan Yang, Lei Yao, Rujing Yin, Gen Zhang, Shaojun Zhang, Feixue Zheng, Ying Zhou, Antti Arola, Johanna Tamminen, Pauli Paasonen, Yele Sun, Lin Wang, Neil M. Donahue, Yongchun Liu, Federico Bianchi, Kaspar R. Daellenbach, Douglas R. Worsnop, Veli-Matti Kerminen, Tuukka Petäjä, Aijun Ding, Jingkun Jiang, and Markku Kulmala
Atmos. Chem. Phys., 22, 12207–12220, https://doi.org/10.5194/acp-22-12207-2022, https://doi.org/10.5194/acp-22-12207-2022, 2022
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Atmospheric new particle formation (NPF) is a dominant source of atmospheric ultrafine particles. In urban environments, traffic emissions are a major source of primary pollutants, but their contribution to NPF remains under debate. During the COVID-19 lockdown, traffic emissions were significantly reduced, providing a unique chance to examine their relevance to NPF. Based on our comprehensive measurements, we demonstrate that traffic emissions alone are not able to explain the NPF in Beijing.
Outi Meinander, Pavla Dagsson-Waldhauserova, Pavel Amosov, Elena Aseyeva, Cliff Atkins, Alexander Baklanov, Clarissa Baldo, Sarah L. Barr, Barbara Barzycka, Liane G. Benning, Bojan Cvetkovic, Polina Enchilik, Denis Frolov, Santiago Gassó, Konrad Kandler, Nikolay Kasimov, Jan Kavan, James King, Tatyana Koroleva, Viktoria Krupskaya, Markku Kulmala, Monika Kusiak, Hanna K. Lappalainen, Michał Laska, Jerome Lasne, Marek Lewandowski, Bartłomiej Luks, James B. McQuaid, Beatrice Moroni, Benjamin Murray, Ottmar Möhler, Adam Nawrot, Slobodan Nickovic, Norman T. O’Neill, Goran Pejanovic, Olga Popovicheva, Keyvan Ranjbar, Manolis Romanias, Olga Samonova, Alberto Sanchez-Marroquin, Kerstin Schepanski, Ivan Semenkov, Anna Sharapova, Elena Shevnina, Zongbo Shi, Mikhail Sofiev, Frédéric Thevenet, Throstur Thorsteinsson, Mikhail Timofeev, Nsikanabasi Silas Umo, Andreas Uppstu, Darya Urupina, György Varga, Tomasz Werner, Olafur Arnalds, and Ana Vukovic Vimic
Atmos. Chem. Phys., 22, 11889–11930, https://doi.org/10.5194/acp-22-11889-2022, https://doi.org/10.5194/acp-22-11889-2022, 2022
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High-latitude dust (HLD) is a short-lived climate forcer, air pollutant, and nutrient source. Our results suggest a northern HLD belt at 50–58° N in Eurasia and 50–55° N in Canada and at >60° N in Eurasia and >58° N in Canada. Our addition to the previously identified global dust belt (GDB) provides crucially needed information on the extent of active HLD sources with both direct and indirect impacts on climate and environment in remote regions, which are often poorly understood and predicted.
Sini Isokääntä, Paul Kim, Santtu Mikkonen, Thomas Kühn, Harri Kokkola, Taina Yli-Juuti, Liine Heikkinen, Krista Luoma, Tuukka Petäjä, Zak Kipling, Daniel Partridge, and Annele Virtanen
Atmos. Chem. Phys., 22, 11823–11843, https://doi.org/10.5194/acp-22-11823-2022, https://doi.org/10.5194/acp-22-11823-2022, 2022
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This research employs air mass history analysis and observations to study how clouds and precipitation affect atmospheric aerosols during transport to a boreal forest site. The mass concentrations of studied chemical species showed exponential decrease as a function of accumulated rain along the air mass route. Our analysis revealed in-cloud sulfate formation, while no major changes in organic mass were seen. Most of the in-cloud-formed sulfate could be assigned to particle sizes above 200 nm.
Runlong Cai, Ella Häkkinen, Chao Yan, Jingkun Jiang, Markku Kulmala, and Juha Kangasluoma
Atmos. Chem. Phys., 22, 11529–11541, https://doi.org/10.5194/acp-22-11529-2022, https://doi.org/10.5194/acp-22-11529-2022, 2022
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The influences of new particle formation on the climate and air quality are governed by particle survival, which has been under debate due to uncertainties in the coagulation sink. Here we measure the coagulation coefficient of sub-10 nm particles and demonstrate that collisions between the freshly nucleated and background particles can effectively lead to coagulation. We further show that the effective coagulation sink is consistent with the new particle formation measured in urban Beijing.
David Martín Belda, Peter Anthoni, David Wårlind, Stefan Olin, Guy Schurgers, Jing Tang, Benjamin Smith, and Almut Arneth
Geosci. Model Dev., 15, 6709–6745, https://doi.org/10.5194/gmd-15-6709-2022, https://doi.org/10.5194/gmd-15-6709-2022, 2022
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We present a number of augmentations to the ecosystem model LPJ-GUESS, which will allow us to use it in studies of the interactions between the land biosphere and the climate. The new module enables calculation of fluxes of energy and water into the atmosphere that are consistent with the modelled vegetation processes. The modelled fluxes are in fair agreement with observations across 21 sites from the FLUXNET network.
Kukka-Maaria Kohonen, Roderick Dewar, Gianluca Tramontana, Aleksanteri Mauranen, Pasi Kolari, Linda M. J. Kooijmans, Dario Papale, Timo Vesala, and Ivan Mammarella
Biogeosciences, 19, 4067–4088, https://doi.org/10.5194/bg-19-4067-2022, https://doi.org/10.5194/bg-19-4067-2022, 2022
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Four different methods for quantifying photosynthesis (GPP) at ecosystem scale were tested, of which two are based on carbon dioxide (CO2) and two on carbonyl sulfide (COS) flux measurements. CO2-based methods are traditional partitioning, and a new method uses machine learning. We introduce a novel method for calculating GPP from COS fluxes, with potentially better applicability than the former methods. Both COS-based methods gave on average higher GPP estimates than the CO2-based estimates.
Benjamin Foreback, Lubna Dada, Kaspar R. Daellenbach, Chao Yan, Lili Wang, Biwu Chu, Ying Zhou, Tom V. Kokkonen, Mona Kurppa, Rosaria E. Pileci, Yonghong Wang, Tommy Chan, Juha Kangasluoma, Lin Zhuohui, Yishou Guo, Chang Li, Rima Baalbaki, Joni Kujansuu, Xiaolong Fan, Zemin Feng, Pekka Rantala, Shahzad Gani, Federico Bianchi, Veli-Matti Kerminen, Tuukka Petäjä, Markku Kulmala, Yongchun Liu, and Pauli Paasonen
Atmos. Chem. Phys., 22, 11089–11104, https://doi.org/10.5194/acp-22-11089-2022, https://doi.org/10.5194/acp-22-11089-2022, 2022
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This study analyzed air quality in Beijing during the Chinese New Year over 7 years, including data from a new in-depth measurement station. This is one of few studies to look at long-term impacts, including the outcome of firework restrictions starting in 2018. Results show that firework pollution has gone down since 2016, indicating a positive result from the restrictions. Results of this study may be useful in making future decisions about the use of fireworks to improve air quality.
Anders Lindroth, Norbert Pirk, Ingibjörg S. Jónsdóttir, Christian Stiegler, Leif Klemedtsson, and Mats B. Nilsson
Biogeosciences, 19, 3921–3934, https://doi.org/10.5194/bg-19-3921-2022, https://doi.org/10.5194/bg-19-3921-2022, 2022
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We measured the fluxes of carbon dioxide and methane between a moist moss tundra and the atmosphere on Svalbard in order to better understand how such ecosystems are affecting the climate and vice versa. We found that the system was a small sink of carbon dioxide and a small source of methane. These fluxes are small in comparison with other tundra ecosystems in the high Arctic. Analysis of temperature sensitivity showed that respiration was more sensitive than photosynthesis above about 6 ℃.
Yishuo Guo, Chao Yan, Yuliang Liu, Xiaohui Qiao, Feixue Zheng, Ying Zhang, Ying Zhou, Chang Li, Xiaolong Fan, Zhuohui Lin, Zemin Feng, Yusheng Zhang, Penggang Zheng, Linhui Tian, Wei Nie, Zhe Wang, Dandan Huang, Kaspar R. Daellenbach, Lei Yao, Lubna Dada, Federico Bianchi, Jingkun Jiang, Yongchun Liu, Veli-Matti Kerminen, and Markku Kulmala
Atmos. Chem. Phys., 22, 10077–10097, https://doi.org/10.5194/acp-22-10077-2022, https://doi.org/10.5194/acp-22-10077-2022, 2022
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Gaseous oxygenated organic molecules (OOMs) are able to form atmospheric aerosols, which will impact on human health and climate change. Here, we find that OOMs in urban Beijing are dominated by anthropogenic sources, i.e. aromatic (29 %–41 %) and aliphatic (26 %–41 %) OOMs. They are also the main contributors to the condensational growth of secondary organic aerosols (SOAs). Therefore, the restriction on anthropogenic VOCs is crucial for the reduction of SOAs and haze formation.
Carlton Xavier, Metin Baykara, Robin Wollesen de Jonge, Barbara Altstädter, Petri Clusius, Ville Vakkari, Roseline Thakur, Lisa Beck, Silvia Becagli, Mirko Severi, Rita Traversi, Radovan Krejci, Peter Tunved, Mauro Mazzola, Birgit Wehner, Mikko Sipilä, Markku Kulmala, Michael Boy, and Pontus Roldin
Atmos. Chem. Phys., 22, 10023–10043, https://doi.org/10.5194/acp-22-10023-2022, https://doi.org/10.5194/acp-22-10023-2022, 2022
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The focus of this work is to study and improve our understanding of processes involved in the formation and growth of new particles in a remote Arctic marine environment. We run the 1D model ADCHEM along air mass trajectories arriving at Ny-Ålesund in May 2018. The model finds that ion-mediated H2SO4–NH3 nucleation can explain the observed new particle formation at Ny-Ålesund. The growth of particles is driven via H2SO4 condensation and formation of methane sulfonic acid in the aqueous phase.
Hannele Hakola, Ditte Taipale, Arnaud Praplan, Simon Schallhart, Steven Thomas, Toni Tykkä, Aku Helin, Jaana Bäck, and Heidi Hellén
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-478, https://doi.org/10.5194/acp-2022-478, 2022
Revised manuscript not accepted
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Norway spruce is one of the main tree species growing in the boreal area. We show that volatile organic compound emission potentials and compound composition vary a lot. We have investigated if e.g. growing location or age of a tree could explain the variations. Recognizing this observed large variability in spruce BVOC emissions (precursors for new particle formation processes), we also tested the consequences of this variability in simulations of aerosol formation.
Ivo Beck, Hélène Angot, Andrea Baccarini, Lubna Dada, Lauriane Quéléver, Tuija Jokinen, Tiia Laurila, Markus Lampimäki, Nicolas Bukowiecki, Matthew Boyer, Xianda Gong, Martin Gysel-Beer, Tuukka Petäjä, Jian Wang, and Julia Schmale
Atmos. Meas. Tech., 15, 4195–4224, https://doi.org/10.5194/amt-15-4195-2022, https://doi.org/10.5194/amt-15-4195-2022, 2022
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We present the pollution detection algorithm (PDA), a new method to identify local primary pollution in remote atmospheric aerosol and trace gas time series. The PDA identifies periods of contaminated data and relies only on the target dataset itself; i.e., it is independent of ancillary data such as meteorological variables. The parameters of all pollution identification steps are adjustable so that the PDA can be tuned to different locations and situations. It is available as open-access code.
Lisa J. Beck, Siegfried Schobesberger, Heikki Junninen, Janne Lampilahti, Antti Manninen, Lubna Dada, Katri Leino, Xu-Cheng He, Iida Pullinen, Lauriane L. J. Quéléver, Anna Franck, Pyry Poutanen, Daniela Wimmer, Frans Korhonen, Mikko Sipilä, Mikael Ehn, Douglas R. Worsnop, Veli-Matti Kerminen, Tuukka Petäjä, Markku Kulmala, and Jonathan Duplissy
Atmos. Chem. Phys., 22, 8547–8577, https://doi.org/10.5194/acp-22-8547-2022, https://doi.org/10.5194/acp-22-8547-2022, 2022
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The presented article introduces an overview of atmospheric ions and their composition above the boreal forest. We provide the results of an extensive airborne measurement campaign with an air ion mass spectrometer and particle measurements, showing their diurnal evolution within the boundary layer and free troposphere. In addition, we compare the airborne dataset with the co-located data from the ground at SMEAR II station, Finland.
Karine Sartelet, Youngseob Kim, Florian Couvidat, Maik Merkel, Tuukka Petäjä, Jean Sciare, and Alfred Wiedensohler
Atmos. Chem. Phys., 22, 8579–8596, https://doi.org/10.5194/acp-22-8579-2022, https://doi.org/10.5194/acp-22-8579-2022, 2022
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A methodology is defined to estimate number emissions from an inventory providing mass emissions. Number concentrations are simulated over Greater Paris using different nucleation parameterisations (binary, ternary involving sulfuric acid and ammonia, and heteromolecular involving sulfuric acid and extremely low-volatility organics, ELVOCs). The comparisons show that ternary nucleation may not be a dominant process for new particle formation in cities, but they stress the role of ELVOCs.
Miska Olin, Magdalena Okuljar, Matti P. Rissanen, Joni Kalliokoski, Jiali Shen, Lubna Dada, Markus Lampimäki, Yusheng Wu, Annalea Lohila, Jonathan Duplissy, Mikko Sipilä, Tuukka Petäjä, Markku Kulmala, and Miikka Dal Maso
Atmos. Chem. Phys., 22, 8097–8115, https://doi.org/10.5194/acp-22-8097-2022, https://doi.org/10.5194/acp-22-8097-2022, 2022
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Atmospheric new particle formation is an important source of the total particle number concentration in the atmosphere. Several parameters for predicting new particle formation events have been suggested before, but the results have been inconclusive. This study proposes an another predicting parameter, related to a specific type of highly oxidized organic molecules, especially for similar locations to the measurement site in this study, which was a coastal agricultural site in Finland.
Joonatan Ala-Könni, Kukka-Maaria Kohonen, Matti Leppäranta, and Ivan Mammarella
Geosci. Model Dev., 15, 4739–4755, https://doi.org/10.5194/gmd-15-4739-2022, https://doi.org/10.5194/gmd-15-4739-2022, 2022
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Properties of seasonally ice-covered lakes are not currently sufficiently included in global climate models. To fill this gap, this study evaluates three models that could be used to quantify the amount of heat that moves from and into the lake by the air above it and through evaporation of the ice cover. The results show that the complex nature of the surrounding environment as well as difficulties in accurately measuring the surface temperature of ice introduce errors to these models.
Malgorzata Golub, Wim Thiery, Rafael Marcé, Don Pierson, Inne Vanderkelen, Daniel Mercado-Bettin, R. Iestyn Woolway, Luke Grant, Eleanor Jennings, Benjamin M. Kraemer, Jacob Schewe, Fang Zhao, Katja Frieler, Matthias Mengel, Vasiliy Y. Bogomolov, Damien Bouffard, Marianne Côté, Raoul-Marie Couture, Andrey V. Debolskiy, Bram Droppers, Gideon Gal, Mingyang Guo, Annette B. G. Janssen, Georgiy Kirillin, Robert Ladwig, Madeline Magee, Tadhg Moore, Marjorie Perroud, Sebastiano Piccolroaz, Love Raaman Vinnaa, Martin Schmid, Tom Shatwell, Victor M. Stepanenko, Zeli Tan, Bronwyn Woodward, Huaxia Yao, Rita Adrian, Mathew Allan, Orlane Anneville, Lauri Arvola, Karen Atkins, Leon Boegman, Cayelan Carey, Kyle Christianson, Elvira de Eyto, Curtis DeGasperi, Maria Grechushnikova, Josef Hejzlar, Klaus Joehnk, Ian D. Jones, Alo Laas, Eleanor B. Mackay, Ivan Mammarella, Hampus Markensten, Chris McBride, Deniz Özkundakci, Miguel Potes, Karsten Rinke, Dale Robertson, James A. Rusak, Rui Salgado, Leon van der Linden, Piet Verburg, Danielle Wain, Nicole K. Ward, Sabine Wollrab, and Galina Zdorovennova
Geosci. Model Dev., 15, 4597–4623, https://doi.org/10.5194/gmd-15-4597-2022, https://doi.org/10.5194/gmd-15-4597-2022, 2022
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Lakes and reservoirs are warming across the globe. To better understand how lakes are changing and to project their future behavior amidst various sources of uncertainty, simulations with a range of lake models are required. This in turn requires international coordination across different lake modelling teams worldwide. Here we present a protocol for and results from coordinated simulations of climate change impacts on lakes worldwide.
Alisa Krasnova, Dmitrii Krasnov, Hans Peter Ernst Cordey, and Steffen M. Noe
EGUsphere, https://doi.org/10.5194/egusphere-2022-384, https://doi.org/10.5194/egusphere-2022-384, 2022
Preprint archived
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Forests play important role in global carbon cycle. Hemiboreal forests are located in a transitional zone between boreal and temperate zones and are characterised by higher variability in dominating tree species. We analysed carbon exchange of a hemiboreal forest using two measurement systems located on the same tower. The lower system could detect the influence of clearcuts and tower guywire tunnels, while the higher system allowed to assess the carbon balance of the full landscape.
Roseline C. Thakur, Lubna Dada, Lisa J. Beck, Lauriane L. J. Quéléver, Tommy Chan, Marjan Marbouti, Xu-Cheng He, Carlton Xavier, Juha Sulo, Janne Lampilahti, Markus Lampimäki, Yee Jun Tham, Nina Sarnela, Katrianne Lehtipalo, Alf Norkko, Markku Kulmala, Mikko Sipilä, and Tuija Jokinen
Atmos. Chem. Phys., 22, 6365–6391, https://doi.org/10.5194/acp-22-6365-2022, https://doi.org/10.5194/acp-22-6365-2022, 2022
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Every year intense cyanobacterial and macroalgal blooms occur in the Baltic Sea and in the coastal areas surrounding Helsinki, yet no studies have addressed the impact of biogenic emissions from these blooms on gas vapor concentrations, which in turn could influence new particle formation. This is the first study of its kind to address the chemistry driving new particle formation (NPF) during a bloom period in this region, highlighting the role of biogenic sulfuric acid and iodic acid.
Ruochong Xu, Joel A. Thornton, Ben H. Lee, Yanxu Zhang, Lyatt Jaeglé, Felipe D. Lopez-Hilfiker, Pekka Rantala, and Tuukka Petäjä
Atmos. Chem. Phys., 22, 5477–5494, https://doi.org/10.5194/acp-22-5477-2022, https://doi.org/10.5194/acp-22-5477-2022, 2022
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Monoterpenes are emitted into the atmosphere by vegetation and by the use of certain consumer products. Reactions of monoterpenes in the atmosphere lead to low-volatility products that condense to grow particulate matter or participate in new particle formation and, thus, affect air quality and climate. We use a model of atmospheric chemistry and transport to evaluate the global-scale importance of recent updates to our understanding of monoterpene chemistry in particle formation and growth.
Minttu Havu, Liisa Kulmala, Pasi Kolari, Timo Vesala, Anu Riikonen, and Leena Järvi
Biogeosciences, 19, 2121–2143, https://doi.org/10.5194/bg-19-2121-2022, https://doi.org/10.5194/bg-19-2121-2022, 2022
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The carbon sequestration potential of two street tree species and the soil beneath them was quantified with the urban land surface model SUEWS and the soil carbon model Yasso. The street tree plantings turned into a modest sink of carbon from the atmosphere after 14 years. Overall, the results indicate the importance of soil in urban carbon sequestration estimations, as soil respiration exceeded the carbon uptake in the early phase, due to the high initial carbon loss from the soil.
Jarmo Mäkelä, Laila Melkas, Ivan Mammarella, Tuomo Nieminen, Suyog Chandramouli, Rafael Savvides, and Kai Puolamäki
Biogeosciences, 19, 2095–2099, https://doi.org/10.5194/bg-19-2095-2022, https://doi.org/10.5194/bg-19-2095-2022, 2022
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Causal structure discovery algorithms have been making headway into Earth system sciences, and they can be used to increase our understanding on biosphere–atmosphere interactions. In this paper we present a procedure on how to utilize prior knowledge of the domain experts together with these algorithms in order to find more robust causal structure models. We also demonstrate how to avoid pitfalls such as over-fitting and concept drift during this process.
Zoé Brasseur, Dimitri Castarède, Erik S. Thomson, Michael P. Adams, Saskia Drossaart van Dusseldorp, Paavo Heikkilä, Kimmo Korhonen, Janne Lampilahti, Mikhail Paramonov, Julia Schneider, Franziska Vogel, Yusheng Wu, Jonathan P. D. Abbatt, Nina S. Atanasova, Dennis H. Bamford, Barbara Bertozzi, Matthew Boyer, David Brus, Martin I. Daily, Romy Fösig, Ellen Gute, Alexander D. Harrison, Paula Hietala, Kristina Höhler, Zamin A. Kanji, Jorma Keskinen, Larissa Lacher, Markus Lampimäki, Janne Levula, Antti Manninen, Jens Nadolny, Maija Peltola, Grace C. E. Porter, Pyry Poutanen, Ulrike Proske, Tobias Schorr, Nsikanabasi Silas Umo, János Stenszky, Annele Virtanen, Dmitri Moisseev, Markku Kulmala, Benjamin J. Murray, Tuukka Petäjä, Ottmar Möhler, and Jonathan Duplissy
Atmos. Chem. Phys., 22, 5117–5145, https://doi.org/10.5194/acp-22-5117-2022, https://doi.org/10.5194/acp-22-5117-2022, 2022
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The present measurement report introduces the ice nucleation campaign organized in Hyytiälä, Finland, in 2018 (HyICE-2018). We provide an overview of the campaign settings, and we describe the measurement infrastructure and operating procedures used. In addition, we use results from ice nucleation instrument inter-comparison to show that the suite of these instruments deployed during the campaign reports consistent results.
Aki Virkkula, Henrik Grythe, John Backman, Tuukka Petäjä, Maurizio Busetto, Christian Lanconelli, Angelo Lupi, Silvia Becagli, Rita Traversi, Mirko Severi, Vito Vitale, Patrick Sheridan, and Elisabeth Andrews
Atmos. Chem. Phys., 22, 5033–5069, https://doi.org/10.5194/acp-22-5033-2022, https://doi.org/10.5194/acp-22-5033-2022, 2022
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Optical properties of surface aerosols at Dome C, Antarctica, in 2007–2013 and their potential source areas are presented. The equivalent black carbon (eBC) mass concentrations were compared with eBC measured at three other Antarctic sites: the South Pole (SPO) and two coastal sites, Neumayer and Syowa. Transport analysis suggests that South American BC emissions are the largest contributor to eBC at Dome C.
Wei Ma, Zemin Feng, Junlei Zhan, Yongchun Liu, Pengfei Liu, Chengtang Liu, Qingxin Ma, Kang Yang, Yafei Wang, Hong He, Markku Kulmala, Yujing Mu, and Junfeng Liu
Atmos. Chem. Phys., 22, 4841–4851, https://doi.org/10.5194/acp-22-4841-2022, https://doi.org/10.5194/acp-22-4841-2022, 2022
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The influence of photochemical loss of volatile organic compounds (VOCS) on O3 formation is investigated using an observation-based model. The sensitivity regime of ozone formation might be misdiagnosed due to the photochemical loss of VOCs in the atmosphere. The contribution of local photochemistry is underestimated regarding O3 pollution when one does not consider the photochemical loss of VOCs.
Joel Kuula, Hilkka Timonen, Jarkko V. Niemi, Hanna E. Manninen, Topi Rönkkö, Tareq Hussein, Pak Lun Fung, Sasu Tarkoma, Mikko Laakso, Erkka Saukko, Aino Ovaska, Markku Kulmala, Ari Karppinen, Lasse Johansson, and Tuukka Petäjä
Atmos. Chem. Phys., 22, 4801–4808, https://doi.org/10.5194/acp-22-4801-2022, https://doi.org/10.5194/acp-22-4801-2022, 2022
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Modern and up-to-date policies and air quality management strategies are instrumental in tackling global air pollution. As the European Union is preparing to revise Ambient Air Quality Directive 2008/50/EC, this paper initiates discussion on selected features of the directive that we believe would benefit from a reassessment. The scientific community has the most recent and deepest understanding of air pollution; thus, its contribution is essential.
Hanna K. Lappalainen, Tuukka Petäjä, Timo Vihma, Jouni Räisänen, Alexander Baklanov, Sergey Chalov, Igor Esau, Ekaterina Ezhova, Matti Leppäranta, Dmitry Pozdnyakov, Jukka Pumpanen, Meinrat O. Andreae, Mikhail Arshinov, Eija Asmi, Jianhui Bai, Igor Bashmachnikov, Boris Belan, Federico Bianchi, Boris Biskaborn, Michael Boy, Jaana Bäck, Bin Cheng, Natalia Chubarova, Jonathan Duplissy, Egor Dyukarev, Konstantinos Eleftheriadis, Martin Forsius, Martin Heimann, Sirkku Juhola, Vladimir Konovalov, Igor Konovalov, Pavel Konstantinov, Kajar Köster, Elena Lapshina, Anna Lintunen, Alexander Mahura, Risto Makkonen, Svetlana Malkhazova, Ivan Mammarella, Stefano Mammola, Stephany Buenrostro Mazon, Outi Meinander, Eugene Mikhailov, Victoria Miles, Stanislav Myslenkov, Dmitry Orlov, Jean-Daniel Paris, Roberta Pirazzini, Olga Popovicheva, Jouni Pulliainen, Kimmo Rautiainen, Torsten Sachs, Vladimir Shevchenko, Andrey Skorokhod, Andreas Stohl, Elli Suhonen, Erik S. Thomson, Marina Tsidilina, Veli-Pekka Tynkkynen, Petteri Uotila, Aki Virkkula, Nadezhda Voropay, Tobias Wolf, Sayaka Yasunaka, Jiahua Zhang, Yubao Qiu, Aijun Ding, Huadong Guo, Valery Bondur, Nikolay Kasimov, Sergej Zilitinkevich, Veli-Matti Kerminen, and Markku Kulmala
Atmos. Chem. Phys., 22, 4413–4469, https://doi.org/10.5194/acp-22-4413-2022, https://doi.org/10.5194/acp-22-4413-2022, 2022
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We summarize results during the last 5 years in the northern Eurasian region, especially from Russia, and introduce recent observations of the air quality in the urban environments in China. Although the scientific knowledge in these regions has increased, there are still gaps in our understanding of large-scale climate–Earth surface interactions and feedbacks. This arises from limitations in research infrastructures and integrative data analyses, hindering a comprehensive system analysis.
Lisa J. Beck, Siegfried Schobesberger, Mikko Sipilä, Veli-Matti Kerminen, and Markku Kulmala
Atmos. Meas. Tech., 15, 1957–1965, https://doi.org/10.5194/amt-15-1957-2022, https://doi.org/10.5194/amt-15-1957-2022, 2022
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Sulfuric acid is known to be a main compound in atmospheric new particle formation. Yet, its concentration is very low, which leads to challenges in detecting it. In our study, we derive the sulfuric acid concentration from measurements of ambient ions with a mass spectrometer. Our validation shows that the theoretical approach using the bisulfate ion and its clusters with H2SO4 captures the sulfuric acid concentration very well during daytime.
Jingwei Zhang, Chaofan Lian, Weigang Wang, Maofa Ge, Yitian Guo, Haiyan Ran, Yusheng Zhang, Feixue Zheng, Xiaolong Fan, Chao Yan, Kaspar R. Daellenbach, Yongchun Liu, Markku Kulmala, and Junling An
Atmos. Chem. Phys., 22, 3275–3302, https://doi.org/10.5194/acp-22-3275-2022, https://doi.org/10.5194/acp-22-3275-2022, 2022
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This study added six potential HONO sources to the WRF-Chem model, evaluated their impact on HONO and O3 concentrations, including surface and vertical concentrations. The simulations extend our knowledge on atmospheric HONO sources, especially for nitrate photolysis. The study also explains the HONO difference in O3 formation on clean and hazy days, and reveals key potential HONO sources to O3 enhancements in haze-aggravating processes with a co-occurrence of high PM2.5 and O3 concentrations.
Marjan Marbouti, Sehyun Jang, Silvia Becagli, Gabriel Navarro, Rita Traversi, Kitack Lee, Tuomo Nieminen, Lisa J. Beck, Markku Kulmala, Veli-Matti Kerminen, and Mikko Sipilä
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-52, https://doi.org/10.5194/acp-2022-52, 2022
Publication in ACP not foreseen
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This research was done to understand and investigate the roles of Chl-a, PP and sea ice extent in controlling and producing the in-situ measured MSA, SA, HIO3, HOM and aerosol concentrations over the Greenland and Barents Seas. Our results provide strong support to the hypothesis that MSA, SA and small-particle concentrations in the Svalbard area are directly linked to ocean biological activity and sea ice melting during springtime.
Timo Vesala, Kukka-Maaria Kohonen, Linda M. J. Kooijmans, Arnaud P. Praplan, Lenka Foltýnová, Pasi Kolari, Markku Kulmala, Jaana Bäck, David Nelson, Dan Yakir, Mark Zahniser, and Ivan Mammarella
Atmos. Chem. Phys., 22, 2569–2584, https://doi.org/10.5194/acp-22-2569-2022, https://doi.org/10.5194/acp-22-2569-2022, 2022
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Carbonyl sulfide (COS) provides new insights into carbon cycle research. We present an easy-to-use flux parameterization and the longest existing time series of forest–atmosphere COS exchange measurements, which allow us to study both seasonal and interannual variability. We observed only uptake of COS by the forest on an annual basis, with 37 % variability between years. Upscaling the boreal COS uptake using a biosphere model indicates a significant missing COS sink at high latitudes.
Tuija Jokinen, Katrianne Lehtipalo, Roseline Cutting Thakur, Ilona Ylivinkka, Kimmo Neitola, Nina Sarnela, Totti Laitinen, Markku Kulmala, Tuukka Petäjä, and Mikko Sipilä
Atmos. Chem. Phys., 22, 2237–2254, https://doi.org/10.5194/acp-22-2237-2022, https://doi.org/10.5194/acp-22-2237-2022, 2022
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New particle formation is an important source of cloud condensation nuclei; however, long-term measurements of aerosol-forming vapors are close to nonexistent in the Arctic. Here, we report 7 months of CI-APi-TOF measurements of sulfuric acid, iodic acid, methane sulfonic acid and the sum of highly oxygenated organic molecules from the SMEAR I station in the Finnish subarctic. The results help us to understand atmospheric chemical processes and aerosol formation in this rapidly changing area.
Olli Nevalainen, Olli Niemitalo, Istem Fer, Antti Juntunen, Tuomas Mattila, Olli Koskela, Joni Kukkamäki, Layla Höckerstedt, Laura Mäkelä, Pieta Jarva, Laura Heimsch, Henriikka Vekuri, Liisa Kulmala, Åsa Stam, Otto Kuusela, Stephanie Gerin, Toni Viskari, Julius Vira, Jari Hyväluoma, Juha-Pekka Tuovinen, Annalea Lohila, Tuomas Laurila, Jussi Heinonsalo, Tuula Aalto, Iivari Kunttu, and Jari Liski
Geosci. Instrum. Method. Data Syst., 11, 93–109, https://doi.org/10.5194/gi-11-93-2022, https://doi.org/10.5194/gi-11-93-2022, 2022
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Better monitoring of soil carbon sequestration is needed to understand the best carbon farming practices in different soils and climate conditions. We, the Field Observatory Network (FiON), have therefore established a methodology for monitoring and forecasting agricultural carbon sequestration by combining offline and near-real-time field measurements, weather data, satellite imagery, and modeling. To disseminate our work, we built a website called the Field Observatory (fieldobservatory.org).
Konstantinos Matthaios Doulgeris, Heikki Lihavainen, Anti-Pekka Hyvärinen, Veli-Matti Kerminen, and David Brus
Earth Syst. Sci. Data, 14, 637–649, https://doi.org/10.5194/essd-14-637-2022, https://doi.org/10.5194/essd-14-637-2022, 2022
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We produced and summarized data sets obtained from two cloud ground-based spectrometers (CAPS and FSSP-100 ground setups) during 8 years of Pallas Cloud Experiment campaigns conducted in autumn from 2004 until 2019 along with several meteorological variables. The campaigns took place in the Finnish sub-Arctic region in a clear environment in temperatures that were usually below zero. This data set provides a helpful contribution to cloud microphysics processes.
Pak Lun Fung, Martha A. Zaidan, Jarkko V. Niemi, Erkka Saukko, Hilkka Timonen, Anu Kousa, Joel Kuula, Topi Rönkkö, Ari Karppinen, Sasu Tarkoma, Markku Kulmala, Tuukka Petäjä, and Tareq Hussein
Atmos. Chem. Phys., 22, 1861–1882, https://doi.org/10.5194/acp-22-1861-2022, https://doi.org/10.5194/acp-22-1861-2022, 2022
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We developed an input-adaptive mixed-effects model, which was automatised to select the best combination of input variables, including up to three fixed effect variables and three time indictors as random effect variables. We tested the model to estimate lung-deposited surface area (LDSA), which correlates well with human health. The results show the inclusion of time indicators improved the sensitivity and the accuracy of the model so that it could serve as a network of virtual sensors.
Jing Cai, Cheng Wu, Jiandong Wang, Wei Du, Feixue Zheng, Simo Hakala, Xiaolong Fan, Biwu Chu, Lei Yao, Zemin Feng, Yongchun Liu, Yele Sun, Jun Zheng, Chao Yan, Federico Bianchi, Markku Kulmala, Claudia Mohr, and Kaspar R. Daellenbach
Atmos. Chem. Phys., 22, 1251–1269, https://doi.org/10.5194/acp-22-1251-2022, https://doi.org/10.5194/acp-22-1251-2022, 2022
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This study investigates the connection between organic aerosol (OA) molecular composition and particle absorptive properties in autumn in Beijing. We find that the molecular properties of OA compounds in different episodes influence particle light absorption properties differently: the light absorption enhancement of black carbon and light absorption coefficient of brown carbon were mostly related to more oxygenated OA (low C number and four O atoms) and aromatics/nitro-aromatics, respectively.
Peifeng Su, Jorma Joutsensaari, Lubna Dada, Martha Arbayani Zaidan, Tuomo Nieminen, Xinyang Li, Yusheng Wu, Stefano Decesari, Sasu Tarkoma, Tuukka Petäjä, Markku Kulmala, and Petri Pellikka
Atmos. Chem. Phys., 22, 1293–1309, https://doi.org/10.5194/acp-22-1293-2022, https://doi.org/10.5194/acp-22-1293-2022, 2022
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We regarded the banana shapes in the surface plots as a special kind of object (similar to cats) and applied an instance segmentation technique to automatically identify the new particle formation (NPF) events (especially the strongest ones), in addition to their growth rates, start times, and end times. The automatic method generalized well on datasets collected in different sites, which is useful for long-term data series analysis and obtaining statistical properties of NPF events.
Anna-Maria Virkkala, Susan M. Natali, Brendan M. Rogers, Jennifer D. Watts, Kathleen Savage, Sara June Connon, Marguerite Mauritz, Edward A. G. Schuur, Darcy Peter, Christina Minions, Julia Nojeim, Roisin Commane, Craig A. Emmerton, Mathias Goeckede, Manuel Helbig, David Holl, Hiroki Iwata, Hideki Kobayashi, Pasi Kolari, Efrén López-Blanco, Maija E. Marushchak, Mikhail Mastepanov, Lutz Merbold, Frans-Jan W. Parmentier, Matthias Peichl, Torsten Sachs, Oliver Sonnentag, Masahito Ueyama, Carolina Voigt, Mika Aurela, Julia Boike, Gerardo Celis, Namyi Chae, Torben R. Christensen, M. Syndonia Bret-Harte, Sigrid Dengel, Han Dolman, Colin W. Edgar, Bo Elberling, Eugenie Euskirchen, Achim Grelle, Juha Hatakka, Elyn Humphreys, Järvi Järveoja, Ayumi Kotani, Lars Kutzbach, Tuomas Laurila, Annalea Lohila, Ivan Mammarella, Yojiro Matsuura, Gesa Meyer, Mats B. Nilsson, Steven F. Oberbauer, Sang-Jong Park, Roman Petrov, Anatoly S. Prokushkin, Christopher Schulze, Vincent L. St. Louis, Eeva-Stiina Tuittila, Juha-Pekka Tuovinen, William Quinton, Andrej Varlagin, Donatella Zona, and Viacheslav I. Zyryanov
Earth Syst. Sci. Data, 14, 179–208, https://doi.org/10.5194/essd-14-179-2022, https://doi.org/10.5194/essd-14-179-2022, 2022
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The effects of climate warming on carbon cycling across the Arctic–boreal zone (ABZ) remain poorly understood due to the relatively limited distribution of ABZ flux sites. Fortunately, this flux network is constantly increasing, but new measurements are published in various platforms, making it challenging to understand the ABZ carbon cycle as a whole. Here, we compiled a new database of Arctic–boreal CO2 fluxes to help facilitate large-scale assessments of the ABZ carbon cycle.
Arto Heitto, Kari Lehtinen, Tuukka Petäjä, Felipe Lopez-Hilfiker, Joel A. Thornton, Markku Kulmala, and Taina Yli-Juuti
Atmos. Chem. Phys., 22, 155–171, https://doi.org/10.5194/acp-22-155-2022, https://doi.org/10.5194/acp-22-155-2022, 2022
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For atmospheric aerosol particles to take part in cloud formation, they need to be at least a few tens of nanometers in diameter. By using a particle condensation model, we investigated how two types of chemical reactions, oligomerization and decomposition, of organic molecules inside the particle may affect the growth of secondary aerosol particles to these sizes. We show that the effect is potentially significant, which highlights the importance of increasing understanding of these processes.
Lukas Fischer, Martin Breitenlechner, Eva Canaval, Wiebke Scholz, Marcus Striednig, Martin Graus, Thomas G. Karl, Tuukka Petäjä, Markku Kulmala, and Armin Hansel
Atmos. Meas. Tech., 14, 8019–8039, https://doi.org/10.5194/amt-14-8019-2021, https://doi.org/10.5194/amt-14-8019-2021, 2021
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Ecosystems emit biogenic volatile organic compounds (BVOCs), which are then oxidized in the atmosphere, contributing to ozone and secondary aerosol formation. While flux measurements of BVOCs are state of the art, flux measurements of the less volatile oxidation products are difficult to achieve due to inlet losses. Here we present first flux measurements, utilizing a novel PTR3 instrument in combination with a specially designed wall-less inlet we put on top of the Hyytiälä tower in Finland.
Linda M. J. Kooijmans, Ara Cho, Jin Ma, Aleya Kaushik, Katherine D. Haynes, Ian Baker, Ingrid T. Luijkx, Mathijs Groenink, Wouter Peters, John B. Miller, Joseph A. Berry, Jerome Ogée, Laura K. Meredith, Wu Sun, Kukka-Maaria Kohonen, Timo Vesala, Ivan Mammarella, Huilin Chen, Felix M. Spielmann, Georg Wohlfahrt, Max Berkelhammer, Mary E. Whelan, Kadmiel Maseyk, Ulli Seibt, Roisin Commane, Richard Wehr, and Maarten Krol
Biogeosciences, 18, 6547–6565, https://doi.org/10.5194/bg-18-6547-2021, https://doi.org/10.5194/bg-18-6547-2021, 2021
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The gas carbonyl sulfide (COS) can be used to estimate photosynthesis. To adopt this approach on regional and global scales, we need biosphere models that can simulate COS exchange. So far, such models have not been evaluated against observations. We evaluate the COS biosphere exchange of the SiB4 model against COS flux observations. We find that the model is capable of simulating key processes in COS biosphere exchange. Still, we give recommendations for further improvement of the model.
Auke J. Visser, Laurens N. Ganzeveld, Ignacio Goded, Maarten C. Krol, Ivan Mammarella, Giovanni Manca, and K. Folkert Boersma
Atmos. Chem. Phys., 21, 18393–18411, https://doi.org/10.5194/acp-21-18393-2021, https://doi.org/10.5194/acp-21-18393-2021, 2021
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Dry deposition is an important sink for tropospheric ozone that affects ecosystem carbon uptake, but process understanding remains incomplete. We apply a common deposition representation in atmospheric chemistry models and a multi-layer canopy model to multi-year ozone deposition observations. The multi-layer canopy model performs better on diurnal timescales compared to the common approach, leading to a substantially improved simulation of ozone deposition and vegetation ozone impact metrics.
Ying Zhou, Simo Hakala, Chao Yan, Yang Gao, Xiaohong Yao, Biwu Chu, Tommy Chan, Juha Kangasluoma, Shahzad Gani, Jenni Kontkanen, Pauli Paasonen, Yongchun Liu, Tuukka Petäjä, Markku Kulmala, and Lubna Dada
Atmos. Chem. Phys., 21, 17885–17906, https://doi.org/10.5194/acp-21-17885-2021, https://doi.org/10.5194/acp-21-17885-2021, 2021
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We characterized the connection between new particle formation (NPF) events in terms of frequency, intensity and growth at a near-highway location in central Beijing and at a background mountain site 80 km away. Due to the substantial contribution of NPF to the global aerosol budget, identifying the conditions that promote the occurrence of regional NPF events could help understand their contribution on a large scale and would improve their implementation in global models.
Mikko Sipilä, Nina Sarnela, Kimmo Neitola, Totti Laitinen, Deniz Kemppainen, Lisa Beck, Ella-Maria Duplissy, Salla Kuittinen, Tuuli Lehmusjärvi, Janne Lampilahti, Veli-Matti Kerminen, Katrianne Lehtipalo, Pasi P. Aalto, Petri Keronen, Erkki Siivola, Pekka A. Rantala, Douglas R. Worsnop, Markku Kulmala, Tuija Jokinen, and Tuukka Petäjä
Atmos. Chem. Phys., 21, 17559–17576, https://doi.org/10.5194/acp-21-17559-2021, https://doi.org/10.5194/acp-21-17559-2021, 2021
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Metallurgical industry in Kola peninsula is a large source of air pollution in the (sub-)Arctic domain. Sulfur dioxide emissions from the ore smelters are transported across large areas. We investigated sulfur dioxide and its transformation to sulfuric acid aerosol particles during winter months in Finnish Lapland, close to Kola industrial areas. We observed intense formation of new aerosol particles despite the low solar radiation intensity, often required for new particle formation elsewhere.
Ditte Taipale, Veli-Matti Kerminen, Mikael Ehn, Markku Kulmala, and Ülo Niinemets
Atmos. Chem. Phys., 21, 17389–17431, https://doi.org/10.5194/acp-21-17389-2021, https://doi.org/10.5194/acp-21-17389-2021, 2021
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Larval feeding and fungal infections of leaves can greatly change the emission of volatile compounds from plants and thereby influence aerosol processes in the air. We developed a model that considers the dynamics of larvae and fungi and the dependency of the emission on the severity of stress. We show that the infections can be highly atmospherically relevant during long periods of time and at times more important to consider than the parameters that are currently used in emission models.
Clémence Rose, Martine Collaud Coen, Elisabeth Andrews, Yong Lin, Isaline Bossert, Cathrine Lund Myhre, Thomas Tuch, Alfred Wiedensohler, Markus Fiebig, Pasi Aalto, Andrés Alastuey, Elisabeth Alonso-Blanco, Marcos Andrade, Begoña Artíñano, Todor Arsov, Urs Baltensperger, Susanne Bastian, Olaf Bath, Johan Paul Beukes, Benjamin T. Brem, Nicolas Bukowiecki, Juan Andrés Casquero-Vera, Sébastien Conil, Konstantinos Eleftheriadis, Olivier Favez, Harald Flentje, Maria I. Gini, Francisco Javier Gómez-Moreno, Martin Gysel-Beer, Anna Gannet Hallar, Ivo Kalapov, Nikos Kalivitis, Anne Kasper-Giebl, Melita Keywood, Jeong Eun Kim, Sang-Woo Kim, Adam Kristensson, Markku Kulmala, Heikki Lihavainen, Neng-Huei Lin, Hassan Lyamani, Angela Marinoni, Sebastiao Martins Dos Santos, Olga L. Mayol-Bracero, Frank Meinhardt, Maik Merkel, Jean-Marc Metzger, Nikolaos Mihalopoulos, Jakub Ondracek, Marco Pandolfi, Noemi Pérez, Tuukka Petäjä, Jean-Eudes Petit, David Picard, Jean-Marc Pichon, Veronique Pont, Jean-Philippe Putaud, Fabienne Reisen, Karine Sellegri, Sangeeta Sharma, Gerhard Schauer, Patrick Sheridan, James Patrick Sherman, Andreas Schwerin, Ralf Sohmer, Mar Sorribas, Junying Sun, Pierre Tulet, Ville Vakkari, Pieter Gideon van Zyl, Fernando Velarde, Paolo Villani, Stergios Vratolis, Zdenek Wagner, Sheng-Hsiang Wang, Kay Weinhold, Rolf Weller, Margarita Yela, Vladimir Zdimal, and Paolo Laj
Atmos. Chem. Phys., 21, 17185–17223, https://doi.org/10.5194/acp-21-17185-2021, https://doi.org/10.5194/acp-21-17185-2021, 2021
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Aerosol particles are a complex component of the atmospheric system the effects of which are among the most uncertain in climate change projections. Using data collected at 62 stations, this study provides the most up-to-date picture of the spatial distribution of particle number concentration and size distribution worldwide, with the aim of contributing to better representation of aerosols and their interactions with clouds in models and, therefore, better evaluation of their impact on climate.
Lucía Caudillo, Birte Rörup, Martin Heinritzi, Guillaume Marie, Mario Simon, Andrea C. Wagner, Tatjana Müller, Manuel Granzin, Antonio Amorim, Farnoush Ataei, Rima Baalbaki, Barbara Bertozzi, Zoé Brasseur, Randall Chiu, Biwu Chu, Lubna Dada, Jonathan Duplissy, Henning Finkenzeller, Loïc Gonzalez Carracedo, Xu-Cheng He, Victoria Hofbauer, Weimeng Kong, Houssni Lamkaddam, Chuan P. Lee, Brandon Lopez, Naser G. A. Mahfouz, Vladimir Makhmutov, Hanna E. Manninen, Ruby Marten, Dario Massabò, Roy L. Mauldin, Bernhard Mentler, Ugo Molteni, Antti Onnela, Joschka Pfeifer, Maxim Philippov, Ana A. Piedehierro, Meredith Schervish, Wiebke Scholz, Benjamin Schulze, Jiali Shen, Dominik Stolzenburg, Yuri Stozhkov, Mihnea Surdu, Christian Tauber, Yee Jun Tham, Ping Tian, António Tomé, Steffen Vogt, Mingyi Wang, Dongyu S. Wang, Stefan K. Weber, André Welti, Wang Yonghong, Wu Yusheng, Marcel Zauner-Wieczorek, Urs Baltensperger, Imad El Haddad, Richard C. Flagan, Armin Hansel, Kristina Höhler, Jasper Kirkby, Markku Kulmala, Katrianne Lehtipalo, Ottmar Möhler, Harald Saathoff, Rainer Volkamer, Paul M. Winkler, Neil M. Donahue, Andreas Kürten, and Joachim Curtius
Atmos. Chem. Phys., 21, 17099–17114, https://doi.org/10.5194/acp-21-17099-2021, https://doi.org/10.5194/acp-21-17099-2021, 2021
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We performed experiments in the CLOUD chamber at CERN at low temperatures to simulate new particle formation in the upper free troposphere (at −30 ºC and −50 ºC). We measured the particle and gas phase and found that most of the compounds present in the gas phase are detected as well in the particle phase. The major compounds in the particles are C8–10 and C18–20. Specifically, we showed that C5 and C15 compounds are detected in a mixed system with isoprene and α-pinene at −30 ºC, 20 % RH.
Anna Franck, Dmitri Moisseev, Ville Vakkari, Matti Leskinen, Janne Lampilahti, Veli-Matti Kerminen, and Ewan O'Connor
Atmos. Meas. Tech., 14, 7341–7353, https://doi.org/10.5194/amt-14-7341-2021, https://doi.org/10.5194/amt-14-7341-2021, 2021
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We proposed a method to derive a convective boundary layer height, using insects in radar observations, and we investigated the consistency of these retrievals among different radar frequencies (5, 35 and 94 GHz). This method can be applied to radars at other measurement stations and serve as additional way to estimate the boundary layer height during summer. The entrainment zone was also observed by the 5 GHz radar above the boundary layer in the form of a Bragg scatter layer.
Krista Luoma, Aki Virkkula, Pasi Aalto, Katrianne Lehtipalo, Tuukka Petäjä, and Markku Kulmala
Atmos. Meas. Tech., 14, 6419–6441, https://doi.org/10.5194/amt-14-6419-2021, https://doi.org/10.5194/amt-14-6419-2021, 2021
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The study presents a comparison of three absorption photometers that measured ambient aerosol particles at a boreal forest site. The study aims to better understand problems related to filter-based measurements. Results show how different correction algorithms, which are used to produce the data, affect the derived optical properties of aerosol particles.
Haoran Li, Ottmar Möhler, Tuukka Petäjä, and Dmitri Moisseev
Atmos. Chem. Phys., 21, 14671–14686, https://doi.org/10.5194/acp-21-14671-2021, https://doi.org/10.5194/acp-21-14671-2021, 2021
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In natural clouds, ice-nucleating particles are expected to be rare above –10 °C. In the current paper, we found that the formation of ice columns is frequent in stratiform clouds and is associated with increased precipitation intensity and liquid water path. In single-layer shallow clouds, the production of ice columns was attributed to secondary ice production, despite the rime-splintering process not being expected to take place in such clouds.
Philipp G. Eger, Luc Vereecken, Rolf Sander, Jan Schuladen, Nicolas Sobanski, Horst Fischer, Einar Karu, Jonathan Williams, Ville Vakkari, Tuukka Petäjä, Jos Lelieveld, Andrea Pozzer, and John N. Crowley
Atmos. Chem. Phys., 21, 14333–14349, https://doi.org/10.5194/acp-21-14333-2021, https://doi.org/10.5194/acp-21-14333-2021, 2021
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We determine the impact of pyruvic acid photolysis on the formation of acetaldehyde and peroxy radicals during summer and autumn in the Finnish boreal forest using a data-constrained box model. Our results are dependent on the chosen scenario in which the overall quantum yield and the photolysis products are varied. We highlight that pyruvic acid photolysis can be an important contributor to acetaldehyde and peroxy radical formation in remote, forested regions.
Mao Xiao, Christopher R. Hoyle, Lubna Dada, Dominik Stolzenburg, Andreas Kürten, Mingyi Wang, Houssni Lamkaddam, Olga Garmash, Bernhard Mentler, Ugo Molteni, Andrea Baccarini, Mario Simon, Xu-Cheng He, Katrianne Lehtipalo, Lauri R. Ahonen, Rima Baalbaki, Paulus S. Bauer, Lisa Beck, David Bell, Federico Bianchi, Sophia Brilke, Dexian Chen, Randall Chiu, António Dias, Jonathan Duplissy, Henning Finkenzeller, Hamish Gordon, Victoria Hofbauer, Changhyuk Kim, Theodore K. Koenig, Janne Lampilahti, Chuan Ping Lee, Zijun Li, Huajun Mai, Vladimir Makhmutov, Hanna E. Manninen, Ruby Marten, Serge Mathot, Roy L. Mauldin, Wei Nie, Antti Onnela, Eva Partoll, Tuukka Petäjä, Joschka Pfeifer, Veronika Pospisilova, Lauriane L. J. Quéléver, Matti Rissanen, Siegfried Schobesberger, Simone Schuchmann, Yuri Stozhkov, Christian Tauber, Yee Jun Tham, António Tomé, Miguel Vazquez-Pufleau, Andrea C. Wagner, Robert Wagner, Yonghong Wang, Lena Weitz, Daniela Wimmer, Yusheng Wu, Chao Yan, Penglin Ye, Qing Ye, Qiaozhi Zha, Xueqin Zhou, Antonio Amorim, Ken Carslaw, Joachim Curtius, Armin Hansel, Rainer Volkamer, Paul M. Winkler, Richard C. Flagan, Markku Kulmala, Douglas R. Worsnop, Jasper Kirkby, Neil M. Donahue, Urs Baltensperger, Imad El Haddad, and Josef Dommen
Atmos. Chem. Phys., 21, 14275–14291, https://doi.org/10.5194/acp-21-14275-2021, https://doi.org/10.5194/acp-21-14275-2021, 2021
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Experiments at CLOUD show that in polluted environments new particle formation (NPF) is largely driven by the formation of sulfuric acid–base clusters, stabilized by amines, high ammonia concentrations or lower temperatures. While oxidation products of aromatics can nucleate, they play a minor role in urban NPF. Our experiments span 4 orders of magnitude variation of observed NPF rates in ambient conditions. We provide a framework based on NPF and growth rates to interpret ambient observations.
Alex Resovsky, Michel Ramonet, Leonard Rivier, Jerome Tarniewicz, Philippe Ciais, Martin Steinbacher, Ivan Mammarella, Meelis Mölder, Michal Heliasz, Dagmar Kubistin, Matthias Lindauer, Jennifer Müller-Williams, Sebastien Conil, and Richard Engelen
Atmos. Meas. Tech., 14, 6119–6135, https://doi.org/10.5194/amt-14-6119-2021, https://doi.org/10.5194/amt-14-6119-2021, 2021
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We present a technical description of a statistical methodology for extracting synoptic- and seasonal-length anomalies from greenhouse gas time series. The definition of what represents an anomalous signal is somewhat subjective, which we touch on throughout the paper. We show, however, that the method performs reasonably well in extracting portions of time series influenced by significant North Atlantic Oscillation weather episodes and continent-wide terrestrial biospheric aberrations.
Yongchun Liu, Zemin Feng, Feixue Zheng, Xiaolei Bao, Pengfei Liu, Yanli Ge, Yan Zhao, Tao Jiang, Yunwen Liao, Yusheng Zhang, Xiaolong Fan, Chao Yan, Biwu Chu, Yonghong Wang, Wei Du, Jing Cai, Federico Bianchi, Tuukka Petäjä, Yujing Mu, Hong He, and Markku Kulmala
Atmos. Chem. Phys., 21, 13269–13286, https://doi.org/10.5194/acp-21-13269-2021, https://doi.org/10.5194/acp-21-13269-2021, 2021
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The mechanisms and kinetics of particulate sulfate formation in the atmosphere are still open questions although they have been extensively discussed. We found that uptake of SO2 is the rate-determining step for the conversion of SO2 to particulate sulfate. NH4NO3 plays an important role in AWC, the phase state of aerosol particles, and subsequently the uptake kinetics of SO2 under high-RH conditions. This work is a good example of the feedback between aerosol physics and aerosol chemistry.
Helmi Uusitalo, Jenni Kontkanen, Ilona Ylivinkka, Ekaterina Ezhova, Anastasiia Demakova, Mikhail Arshinov, Boris Denisovich Belan, Denis Davydov, Nan Ma, Tuukka Petäjä, Alfred Wiedensohler, Markku Kulmala, and Tuomo Nieminen
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-530, https://doi.org/10.5194/acp-2021-530, 2021
Publication in ACP not foreseen
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Characteristics of formation of atmospheric aerosol at four boreal forest sites in Finland and Russian Siberia was analyzed. Our results provide information on the governing processes of atmospheric aerosol formation in the boreal forest area, which a substantial part of the continental biosphere. Aerosol formation was occurring less frequently at Siberian than in Finnish sites, which was affected by the lower particle growth rates and higher loss rates in Siberia.
Nahid Atashi, Dariush Rahimi, Victoria A. Sinclair, Martha A. Zaidan, Anton Rusanen, Henri Vuollekoski, Markku Kulmala, Timo Vesala, and Tareq Hussein
Hydrol. Earth Syst. Sci., 25, 4719–4740, https://doi.org/10.5194/hess-25-4719-2021, https://doi.org/10.5194/hess-25-4719-2021, 2021
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Dew formation potential during a long-term period (1979–2018) was assessed in Iran to identify dew formation zones and to investigate the impacts of long-term variation in meteorological parameters on dew formation. Six dew formation zones were identified based on cluster analysis of the time series of the simulated dew yield. The distribution of dew formation zones in Iran was closely aligned with topography and sources of moisture. The dew formation trend was significantly negative.
Janne Lampilahti, Hanna E. Manninen, Tuomo Nieminen, Sander Mirme, Mikael Ehn, Iida Pullinen, Katri Leino, Siegfried Schobesberger, Juha Kangasluoma, Jenni Kontkanen, Emma Järvinen, Riikka Väänänen, Taina Yli-Juuti, Radovan Krejci, Katrianne Lehtipalo, Janne Levula, Aadu Mirme, Stefano Decesari, Ralf Tillmann, Douglas R. Worsnop, Franz Rohrer, Astrid Kiendler-Scharr, Tuukka Petäjä, Veli-Matti Kerminen, Thomas F. Mentel, and Markku Kulmala
Atmos. Chem. Phys., 21, 12649–12663, https://doi.org/10.5194/acp-21-12649-2021, https://doi.org/10.5194/acp-21-12649-2021, 2021
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We studied aerosol particle formation and growth in different parts of the planetary boundary layer at two different locations (Po Valley, Italy, and Hyytiälä, Finland). The observations consist of airborne measurements on board an instrumented Zeppelin and a small airplane combined with comprehensive ground-based measurements.
Pavel Alekseychik, Aino Korrensalo, Ivan Mammarella, Samuli Launiainen, Eeva-Stiina Tuittila, Ilkka Korpela, and Timo Vesala
Biogeosciences, 18, 4681–4704, https://doi.org/10.5194/bg-18-4681-2021, https://doi.org/10.5194/bg-18-4681-2021, 2021
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Bogs of northern Eurasia represent a major type of peatland ecosystem and contain vast amounts of carbon, but carbon balance monitoring studies on bogs are scarce. The current project explores 6 years of carbon balance data obtained using the state-of-the-art eddy-covariance technique at a Finnish bog Siikaneva. The results reveal relatively low interannual variability indicative of ecosystem resilience to both cool and hot summers and provide new insights into the seasonal course of C fluxes.
Zhuohui Lin, Yonghong Wang, Feixue Zheng, Ying Zhou, Yishuo Guo, Zemin Feng, Chang Li, Yusheng Zhang, Simo Hakala, Tommy Chan, Chao Yan, Kaspar R. Daellenbach, Biwu Chu, Lubna Dada, Juha Kangasluoma, Lei Yao, Xiaolong Fan, Wei Du, Jing Cai, Runlong Cai, Tom V. Kokkonen, Putian Zhou, Lili Wang, Tuukka Petäjä, Federico Bianchi, Veli-Matti Kerminen, Yongchun Liu, and Markku Kulmala
Atmos. Chem. Phys., 21, 12173–12187, https://doi.org/10.5194/acp-21-12173-2021, https://doi.org/10.5194/acp-21-12173-2021, 2021
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We find that ammonium nitrate and aerosol water content contributed most during low mixing layer height conditions; this may further trigger enhanced formation of sulfate and organic aerosol via heterogeneous reactions. The results of this study contribute towards a more detailed understanding of the aerosol–chemistry–radiation–boundary layer feedback that is likely to be responsible for explosive aerosol mass growth events in urban Beijing.
Pak Lun Fung, Martha Arbayani Zaidan, Ola Surakhi, Sasu Tarkoma, Tuukka Petäjä, and Tareq Hussein
Atmos. Meas. Tech., 14, 5535–5554, https://doi.org/10.5194/amt-14-5535-2021, https://doi.org/10.5194/amt-14-5535-2021, 2021
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Aerosol size distribution measurements rely on a variety of techniques to classify the aerosol size and measure the size distribution. However, due to the instrumental insufficiency and inversion limitations, the raw dataset contains missing gaps or negative values, which hinder further analysis. With a merged particle size distribution in Jordan, this paper suggests a neural network method to estimate number concentrations at a particular size bin by the number concentration at other size bins.
Dimitrios Bousiotis, Francis D. Pope, David C. S. Beddows, Manuel Dall'Osto, Andreas Massling, Jakob Klenø Nøjgaard, Claus Nordstrøm, Jarkko V. Niemi, Harri Portin, Tuukka Petäjä, Noemi Perez, Andrés Alastuey, Xavier Querol, Giorgos Kouvarakis, Nikos Mihalopoulos, Stergios Vratolis, Konstantinos Eleftheriadis, Alfred Wiedensohler, Kay Weinhold, Maik Merkel, Thomas Tuch, and Roy M. Harrison
Atmos. Chem. Phys., 21, 11905–11925, https://doi.org/10.5194/acp-21-11905-2021, https://doi.org/10.5194/acp-21-11905-2021, 2021
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Formation of new particles is a key process in the atmosphere. New particle formation events arising from nucleation of gaseous precursors have been analysed in extensive datasets from 13 sites in five European countries in terms of frequency, nucleation rate, and particle growth rate, with several common features and many differences identified. Although nucleation frequencies are lower at roadside sites, nucleation rates and particle growth rates are typically higher.
Luis M. F. Barreira, Arttu Ylisirniö, Iida Pullinen, Angela Buchholz, Zijun Li, Helina Lipp, Heikki Junninen, Urmas Hõrrak, Steffen M. Noe, Alisa Krasnova, Dmitrii Krasnov, Kaia Kask, Eero Talts, Ülo Niinemets, Jose Ruiz-Jimenez, and Siegfried Schobesberger
Atmos. Chem. Phys., 21, 11781–11800, https://doi.org/10.5194/acp-21-11781-2021, https://doi.org/10.5194/acp-21-11781-2021, 2021
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We present results from PM1 atmospheric composition and concentration measurements performed in a springtime hemiboreal forest. Sesquiterpene mixing ratios and particle-phase concentrations of corresponding oxidation products were rapidly increasing on some early mornings. The particle volatility suggested that condensable sesquiterpene oxidation products are rapidly formed in the atmosphere. The results revealed the importance of sesquiterpenes for secondary organic aerosol particulate mass.
Kyle B. Delwiche, Sara Helen Knox, Avni Malhotra, Etienne Fluet-Chouinard, Gavin McNicol, Sarah Feron, Zutao Ouyang, Dario Papale, Carlo Trotta, Eleonora Canfora, You-Wei Cheah, Danielle Christianson, Ma. Carmelita R. Alberto, Pavel Alekseychik, Mika Aurela, Dennis Baldocchi, Sheel Bansal, David P. Billesbach, Gil Bohrer, Rosvel Bracho, Nina Buchmann, David I. Campbell, Gerardo Celis, Jiquan Chen, Weinan Chen, Housen Chu, Higo J. Dalmagro, Sigrid Dengel, Ankur R. Desai, Matteo Detto, Han Dolman, Elke Eichelmann, Eugenie Euskirchen, Daniela Famulari, Kathrin Fuchs, Mathias Goeckede, Sébastien Gogo, Mangaliso J. Gondwe, Jordan P. Goodrich, Pia Gottschalk, Scott L. Graham, Martin Heimann, Manuel Helbig, Carole Helfter, Kyle S. Hemes, Takashi Hirano, David Hollinger, Lukas Hörtnagl, Hiroki Iwata, Adrien Jacotot, Gerald Jurasinski, Minseok Kang, Kuno Kasak, John King, Janina Klatt, Franziska Koebsch, Ken W. Krauss, Derrick Y. F. Lai, Annalea Lohila, Ivan Mammarella, Luca Belelli Marchesini, Giovanni Manca, Jaclyn Hatala Matthes, Trofim Maximov, Lutz Merbold, Bhaskar Mitra, Timothy H. Morin, Eiko Nemitz, Mats B. Nilsson, Shuli Niu, Walter C. Oechel, Patricia Y. Oikawa, Keisuke Ono, Matthias Peichl, Olli Peltola, Michele L. Reba, Andrew D. Richardson, William Riley, Benjamin R. K. Runkle, Youngryel Ryu, Torsten Sachs, Ayaka Sakabe, Camilo Rey Sanchez, Edward A. Schuur, Karina V. R. Schäfer, Oliver Sonnentag, Jed P. Sparks, Ellen Stuart-Haëntjens, Cove Sturtevant, Ryan C. Sullivan, Daphne J. Szutu, Jonathan E. Thom, Margaret S. Torn, Eeva-Stiina Tuittila, Jessica Turner, Masahito Ueyama, Alex C. Valach, Rodrigo Vargas, Andrej Varlagin, Alma Vazquez-Lule, Joseph G. Verfaillie, Timo Vesala, George L. Vourlitis, Eric J. Ward, Christian Wille, Georg Wohlfahrt, Guan Xhuan Wong, Zhen Zhang, Donatella Zona, Lisamarie Windham-Myers, Benjamin Poulter, and Robert B. Jackson
Earth Syst. Sci. Data, 13, 3607–3689, https://doi.org/10.5194/essd-13-3607-2021, https://doi.org/10.5194/essd-13-3607-2021, 2021
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Methane is an important greenhouse gas, yet we lack knowledge about its global emissions and drivers. We present FLUXNET-CH4, a new global collection of methane measurements and a critical resource for the research community. We use FLUXNET-CH4 data to quantify the seasonality of methane emissions from freshwater wetlands, finding that methane seasonality varies strongly with latitude. Our new database and analysis will improve wetland model accuracy and inform greenhouse gas budgets.
Xiaolong Fan, Jing Cai, Chao Yan, Jian Zhao, Yishuo Guo, Chang Li, Kaspar R. Dällenbach, Feixue Zheng, Zhuohui Lin, Biwu Chu, Yonghong Wang, Lubna Dada, Qiaozhi Zha, Wei Du, Jenni Kontkanen, Theo Kurtén, Siddhart Iyer, Joni T. Kujansuu, Tuukka Petäjä, Douglas R. Worsnop, Veli-Matti Kerminen, Yongchun Liu, Federico Bianchi, Yee Jun Tham, Lei Yao, and Markku Kulmala
Atmos. Chem. Phys., 21, 11437–11452, https://doi.org/10.5194/acp-21-11437-2021, https://doi.org/10.5194/acp-21-11437-2021, 2021
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We observed significant concentrations of gaseous HBr and HCl throughout the winter and springtime in urban Beijing, China. Our results indicate that gaseous HCl and HBr are most likely originated from anthropogenic emissions such as burning activities, and the gas–aerosol partitioning may play a crucial role in contributing to the gaseous HCl and HBr. These observations suggest that there is an important recycling pathway of halogen species in inland megacities.
Toprak Aslan, Olli Peltola, Andreas Ibrom, Eiko Nemitz, Üllar Rannik, and Ivan Mammarella
Atmos. Meas. Tech., 14, 5089–5106, https://doi.org/10.5194/amt-14-5089-2021, https://doi.org/10.5194/amt-14-5089-2021, 2021
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Vertical turbulent fluxes of gases measured by the eddy covariance (EC) technique are subject to high-frequency losses. There are different methods used to describe this low-pass filtering effect and to correct the measured fluxes. In this study, we analysed the systematic uncertainty related to this correction for various attenuation and signal-to-noise ratios. A new and robust transfer function method is finally proposed.
Olli Peltola, Toprak Aslan, Andreas Ibrom, Eiko Nemitz, Üllar Rannik, and Ivan Mammarella
Atmos. Meas. Tech., 14, 5071–5088, https://doi.org/10.5194/amt-14-5071-2021, https://doi.org/10.5194/amt-14-5071-2021, 2021
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Gas fluxes measured by the eddy covariance (EC) technique are subject to filtering due to non-ideal instrumentation. For linear first-order systems this filtering causes also a time lag between vertical wind speed and gas signal which is additional to the gas travel time in the sampling line. The effect of this additional time lag on EC fluxes is ignored in current EC data processing routines. Here we show that this oversight biases EC fluxes and hence propose an approach to rectify this bias.
Haijie Tong, Fobang Liu, Alexander Filippi, Jake Wilson, Andrea M. Arangio, Yun Zhang, Siyao Yue, Steven Lelieveld, Fangxia Shen, Helmi-Marja K. Keskinen, Jing Li, Haoxuan Chen, Ting Zhang, Thorsten Hoffmann, Pingqing Fu, William H. Brune, Tuukka Petäjä, Markku Kulmala, Maosheng Yao, Thomas Berkemeier, Manabu Shiraiwa, and Ulrich Pöschl
Atmos. Chem. Phys., 21, 10439–10455, https://doi.org/10.5194/acp-21-10439-2021, https://doi.org/10.5194/acp-21-10439-2021, 2021
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We measured radical yields of aqueous PM2.5 extracts and found lower yields at higher concentrations of PM2.5. Abundances of water-soluble transition metals and aromatics in PM2.5 were positively correlated with the relative fraction of •OH but negatively correlated with the relative fraction of C-centered radicals among detected radicals. Composition-dependent reactive species yields may explain differences in the reactivity and health effects of PM2.5 in clean versus polluted air.
Liine Heikkinen, Mikko Äijälä, Kaspar R. Daellenbach, Gang Chen, Olga Garmash, Diego Aliaga, Frans Graeffe, Meri Räty, Krista Luoma, Pasi Aalto, Markku Kulmala, Tuukka Petäjä, Douglas Worsnop, and Mikael Ehn
Atmos. Chem. Phys., 21, 10081–10109, https://doi.org/10.5194/acp-21-10081-2021, https://doi.org/10.5194/acp-21-10081-2021, 2021
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In many locations worldwide aerosol particles have been shown to be made up of organic aerosol (OA). The boreal forest is a region where aerosol particles possess a high OA mass fraction. Here, we studied OA composition using the longest time series of OA composition ever obtained from a boreal environment. For this purpose, we tested a new analysis framework and discovered that most of the OA was highly oxidized, with strong seasonal behaviour reflecting different sources in summer and winter.
Magdalena Okuljar, Heino Kuuluvainen, Jenni Kontkanen, Olga Garmash, Miska Olin, Jarkko V. Niemi, Hilkka Timonen, Juha Kangasluoma, Yee Jun Tham, Rima Baalbaki, Mikko Sipilä, Laura Salo, Henna Lintusaari, Harri Portin, Kimmo Teinilä, Minna Aurela, Miikka Dal Maso, Topi Rönkkö, Tuukka Petäjä, and Pauli Paasonen
Atmos. Chem. Phys., 21, 9931–9953, https://doi.org/10.5194/acp-21-9931-2021, https://doi.org/10.5194/acp-21-9931-2021, 2021
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To estimate the relative contribution of different sources to the particle population in an urban environment, we conducted simultaneous measurements at a street canyon and an urban background station in Helsinki. We investigated the contribution of traffic and new particle formation to particles with a diameter between 1 and 800 nm. We found that during spring traffic does not dominate the particles smaller than 3 nm at either of the stations.
Rima Baalbaki, Michael Pikridas, Tuija Jokinen, Tiia Laurila, Lubna Dada, Spyros Bezantakos, Lauri Ahonen, Kimmo Neitola, Anne Maisser, Elie Bimenyimana, Aliki Christodoulou, Florin Unga, Chrysanthos Savvides, Katrianne Lehtipalo, Juha Kangasluoma, George Biskos, Tuukka Petäjä, Veli-Matti Kerminen, Jean Sciare, and Markku Kulmala
Atmos. Chem. Phys., 21, 9223–9251, https://doi.org/10.5194/acp-21-9223-2021, https://doi.org/10.5194/acp-21-9223-2021, 2021
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This study investigates new particle formation (NPF) in the less represented region of the Mediterranean basin using 1-year measurements of aerosol particles down to ~ 1 nm in diameter. We report a high frequency of NPF and give examples of interesting NPF features. We quantify the strength of NPF events by calculating formation rates and growth rates. We further unveil the atmospheric conditions and variables considered important for the intra-monthly and inter-monthly occurrence of NPF.
Rafael Poyatos, Víctor Granda, Víctor Flo, Mark A. Adams, Balázs Adorján, David Aguadé, Marcos P. M. Aidar, Scott Allen, M. Susana Alvarado-Barrientos, Kristina J. Anderson-Teixeira, Luiza Maria Aparecido, M. Altaf Arain, Ismael Aranda, Heidi Asbjornsen, Robert Baxter, Eric Beamesderfer, Z. Carter Berry, Daniel Berveiller, Bethany Blakely, Johnny Boggs, Gil Bohrer, Paul V. Bolstad, Damien Bonal, Rosvel Bracho, Patricia Brito, Jason Brodeur, Fernando Casanoves, Jérôme Chave, Hui Chen, Cesar Cisneros, Kenneth Clark, Edoardo Cremonese, Hongzhong Dang, Jorge S. David, Teresa S. David, Nicolas Delpierre, Ankur R. Desai, Frederic C. Do, Michal Dohnal, Jean-Christophe Domec, Sebinasi Dzikiti, Colin Edgar, Rebekka Eichstaedt, Tarek S. El-Madany, Jan Elbers, Cleiton B. Eller, Eugénie S. Euskirchen, Brent Ewers, Patrick Fonti, Alicia Forner, David I. Forrester, Helber C. Freitas, Marta Galvagno, Omar Garcia-Tejera, Chandra Prasad Ghimire, Teresa E. Gimeno, John Grace, André Granier, Anne Griebel, Yan Guangyu, Mark B. Gush, Paul J. Hanson, Niles J. Hasselquist, Ingo Heinrich, Virginia Hernandez-Santana, Valentine Herrmann, Teemu Hölttä, Friso Holwerda, James Irvine, Supat Isarangkool Na Ayutthaya, Paul G. Jarvis, Hubert Jochheim, Carlos A. Joly, Julia Kaplick, Hyun Seok Kim, Leif Klemedtsson, Heather Kropp, Fredrik Lagergren, Patrick Lane, Petra Lang, Andrei Lapenas, Víctor Lechuga, Minsu Lee, Christoph Leuschner, Jean-Marc Limousin, Juan Carlos Linares, Maj-Lena Linderson, Anders Lindroth, Pilar Llorens, Álvaro López-Bernal, Michael M. Loranty, Dietmar Lüttschwager, Cate Macinnis-Ng, Isabelle Maréchaux, Timothy A. Martin, Ashley Matheny, Nate McDowell, Sean McMahon, Patrick Meir, Ilona Mészáros, Mirco Migliavacca, Patrick Mitchell, Meelis Mölder, Leonardo Montagnani, Georgianne W. Moore, Ryogo Nakada, Furong Niu, Rachael H. Nolan, Richard Norby, Kimberly Novick, Walter Oberhuber, Nikolaus Obojes, A. Christopher Oishi, Rafael S. Oliveira, Ram Oren, Jean-Marc Ourcival, Teemu Paljakka, Oscar Perez-Priego, Pablo L. Peri, Richard L. Peters, Sebastian Pfautsch, William T. Pockman, Yakir Preisler, Katherine Rascher, George Robinson, Humberto Rocha, Alain Rocheteau, Alexander Röll, Bruno H. P. Rosado, Lucy Rowland, Alexey V. Rubtsov, Santiago Sabaté, Yann Salmon, Roberto L. Salomón, Elisenda Sánchez-Costa, Karina V. R. Schäfer, Bernhard Schuldt, Alexandr Shashkin, Clément Stahl, Marko Stojanović, Juan Carlos Suárez, Ge Sun, Justyna Szatniewska, Fyodor Tatarinov, Miroslav Tesař, Frank M. Thomas, Pantana Tor-ngern, Josef Urban, Fernando Valladares, Christiaan van der Tol, Ilja van Meerveld, Andrej Varlagin, Holm Voigt, Jeffrey Warren, Christiane Werner, Willy Werner, Gerhard Wieser, Lisa Wingate, Stan Wullschleger, Koong Yi, Roman Zweifel, Kathy Steppe, Maurizio Mencuccini, and Jordi Martínez-Vilalta
Earth Syst. Sci. Data, 13, 2607–2649, https://doi.org/10.5194/essd-13-2607-2021, https://doi.org/10.5194/essd-13-2607-2021, 2021
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Transpiration is a key component of global water balance, but it is poorly constrained from available observations. We present SAPFLUXNET, the first global database of tree-level transpiration from sap flow measurements, containing 202 datasets and covering a wide range of ecological conditions. SAPFLUXNET and its accompanying R software package
sapfluxnetrwill facilitate new data syntheses on the ecological factors driving water use and drought responses of trees and forests.
Wei Huang, Haiyan Li, Nina Sarnela, Liine Heikkinen, Yee Jun Tham, Jyri Mikkilä, Steven J. Thomas, Neil M. Donahue, Markku Kulmala, and Federico Bianchi
Atmos. Chem. Phys., 21, 8961–8977, https://doi.org/10.5194/acp-21-8961-2021, https://doi.org/10.5194/acp-21-8961-2021, 2021
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We show full characterization of gaseous organic compounds in a boreal forest. Molecular composition and volatility of gaseous organic compounds with different oxidation extents (from volatile organic compounds to highly oxygenated organic molecules) were investigated and discussed. We provide a more comprehensive understanding of atmospheric organic compounds in this boreal forest and new insights into interpreting ambient measurements or testing and improving parameterizations in models.
Jose Ruiz-Jimenez, Magdalena Okuljar, Outi-Maaria Sietiö, Giorgia Demaria, Thanaporn Liangsupree, Elisa Zagatti, Juho Aalto, Kari Hartonen, Jussi Heinonsalo, Jaana Bäck, Tuukka Petäjä, and Marja-Liisa Riekkola
Atmos. Chem. Phys., 21, 8775–8790, https://doi.org/10.5194/acp-21-8775-2021, https://doi.org/10.5194/acp-21-8775-2021, 2021
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Altogether, 84 size-segregated aerosol samples from four particle size fractions were collected at the Station for Measuring Forest Ecosystem-Atmosphere Relations, Hyytiälä, Finland, in autumn 2017 for the clarification of the complex interrelationships between airborne and particulate chemical traces, amino acids and saccharides, gene copy numbers (16S and 18S for bacteria and fungi, respectively), gas-phase chemistry, and the particle size distribution.
Laura Heimsch, Annalea Lohila, Juha-Pekka Tuovinen, Henriikka Vekuri, Jussi Heinonsalo, Olli Nevalainen, Mika Korkiakoski, Jari Liski, Tuomas Laurila, and Liisa Kulmala
Biogeosciences, 18, 3467–3483, https://doi.org/10.5194/bg-18-3467-2021, https://doi.org/10.5194/bg-18-3467-2021, 2021
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CO2 and H2O fluxes were measured at a newly established eddy covariance site in southern Finland for 2 years from 2018 to 2020. This agricultural grassland site focuses on the conversion from intensive towards more sustainable agricultural management. The first summer experienced prolonged dry periods, and notably larger fluxes were observed in the second summer. The field acted as a net carbon sink during both study years.
Mingyi Wang, Xu-Cheng He, Henning Finkenzeller, Siddharth Iyer, Dexian Chen, Jiali Shen, Mario Simon, Victoria Hofbauer, Jasper Kirkby, Joachim Curtius, Norbert Maier, Theo Kurtén, Douglas R. Worsnop, Markku Kulmala, Matti Rissanen, Rainer Volkamer, Yee Jun Tham, Neil M. Donahue, and Mikko Sipilä
Atmos. Meas. Tech., 14, 4187–4202, https://doi.org/10.5194/amt-14-4187-2021, https://doi.org/10.5194/amt-14-4187-2021, 2021
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Atmospheric iodine species are often short-lived with low abundance and have thus been challenging to measure. We show that the bromide chemical ionization mass spectrometry, compatible with both the atmospheric pressure and reduced pressure interfaces, can simultaneously detect various gas-phase iodine species. Combining calibration experiments and quantum chemical calculations, we quantify detection sensitivities to HOI, HIO3, I2, and H2SO4, giving detection limits down to < 106 molec. cm-3.
Anna B. Harper, Karina E. Williams, Patrick C. McGuire, Maria Carolina Duran Rojas, Debbie Hemming, Anne Verhoef, Chris Huntingford, Lucy Rowland, Toby Marthews, Cleiton Breder Eller, Camilla Mathison, Rodolfo L. B. Nobrega, Nicola Gedney, Pier Luigi Vidale, Fred Otu-Larbi, Divya Pandey, Sebastien Garrigues, Azin Wright, Darren Slevin, Martin G. De Kauwe, Eleanor Blyth, Jonas Ardö, Andrew Black, Damien Bonal, Nina Buchmann, Benoit Burban, Kathrin Fuchs, Agnès de Grandcourt, Ivan Mammarella, Lutz Merbold, Leonardo Montagnani, Yann Nouvellon, Natalia Restrepo-Coupe, and Georg Wohlfahrt
Geosci. Model Dev., 14, 3269–3294, https://doi.org/10.5194/gmd-14-3269-2021, https://doi.org/10.5194/gmd-14-3269-2021, 2021
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We evaluated 10 representations of soil moisture stress in the JULES land surface model against site observations of GPP and latent heat flux. Increasing the soil depth and plant access to deep soil moisture improved many aspects of the simulations, and we recommend these settings in future work using JULES. In addition, using soil matric potential presents the opportunity to include parameters specific to plant functional type to further improve modeled fluxes.
Markku Kulmala, Tom V. Kokkonen, Juha Pekkanen, Sami Paatero, Tuukka Petäjä, Veli-Matti Kerminen, and Aijun Ding
Atmos. Chem. Phys., 21, 8313–8322, https://doi.org/10.5194/acp-21-8313-2021, https://doi.org/10.5194/acp-21-8313-2021, 2021
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The eastern part of China as a whole is practically a gigacity with 650 million inhabitants. The gigacity, with its emissions, processes in the pollution cocktail and numerous feedbacks and interactions, has a crucial and big impact on regional air quality and on global climate. A large-scale research and innovation program is needed to meet the interlinked grand challenges in this gigacity and to serve as a platform for finding pathways for sustainable development of the globe.
Heidi Hellén, Arnaud P. Praplan, Toni Tykkä, Aku Helin, Simon Schallhart, Piia P. Schiestl-Aalto, Jaana Bäck, and Hannele Hakola
Atmos. Chem. Phys., 21, 8045–8066, https://doi.org/10.5194/acp-21-8045-2021, https://doi.org/10.5194/acp-21-8045-2021, 2021
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Even though terpene emissions of boreal needle trees have been studied quite intensively, there is less knowledge of the emissions of broadleaved deciduous trees and emissions of larger terpenes and oxygenated volatile organic compounds. Here we studied downy birch (Betula pubescens) emissions, and especially sesquiterpene and oxygenated sesquiterpene emissions were found to be high. These emissions may have significant effects on secondary organic aerosol formation in boreal areas.
Janne Lampilahti, Katri Leino, Antti Manninen, Pyry Poutanen, Anna Franck, Maija Peltola, Paula Hietala, Lisa Beck, Lubna Dada, Lauriane Quéléver, Ronja Öhrnberg, Ying Zhou, Madeleine Ekblom, Ville Vakkari, Sergej Zilitinkevich, Veli-Matti Kerminen, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 21, 7901–7915, https://doi.org/10.5194/acp-21-7901-2021, https://doi.org/10.5194/acp-21-7901-2021, 2021
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Using airborne measurements we observed increased number concentrations of sub-25 nm particles in the upper residual layer. These particles may be entrained into the well-mixed boundary layer and observed at the surface. We attribute our observations to new particle formation in the topmost part of the residual layer.
Yishuo Guo, Chao Yan, Chang Li, Wei Ma, Zemin Feng, Ying Zhou, Zhuohui Lin, Lubna Dada, Dominik Stolzenburg, Rujing Yin, Jenni Kontkanen, Kaspar R. Daellenbach, Juha Kangasluoma, Lei Yao, Biwu Chu, Yonghong Wang, Runlong Cai, Federico Bianchi, Yongchun Liu, and Markku Kulmala
Atmos. Chem. Phys., 21, 5499–5511, https://doi.org/10.5194/acp-21-5499-2021, https://doi.org/10.5194/acp-21-5499-2021, 2021
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Fog, cloud and haze are very common natural phenomena. Sulfuric acid (SA) is one of the key compounds forming those suspended particles, technically called aerosols, through gas-to-particle conversion. Therefore, the concentration level, source and sink of SA is very important. Our results show that ozonolysis of alkenes plays a major role in nighttime SA formation under unpolluted conditions in urban Beijing, and nighttime cluster mode particles are probably driven by SA in urban environments.
Dana L. McGuffin, Yuanlong Huang, Richard C. Flagan, Tuukka Petäjä, B. Erik Ydstie, and Peter J. Adams
Geosci. Model Dev., 14, 1821–1839, https://doi.org/10.5194/gmd-14-1821-2021, https://doi.org/10.5194/gmd-14-1821-2021, 2021
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Atmospheric particle formation, emissions, and growth process rates are significant sources of uncertainty in predicting climate change. We aim to reduce that uncertainty by using measurements from several ground-based sites across Europe. We developed an estimation technique to adapt the governing process rates so model–measurement bias decays. The estimation framework developed has potential to improve model predictions while providing insight into the underlying atmospheric particle physics.
Thomas Thorp, Stephen R. Arnold, Richard J. Pope, Dominick V. Spracklen, Luke Conibear, Christoph Knote, Mikhail Arshinov, Boris Belan, Eija Asmi, Tuomas Laurila, Andrei I. Skorokhod, Tuomo Nieminen, and Tuukka Petäjä
Atmos. Chem. Phys., 21, 4677–4697, https://doi.org/10.5194/acp-21-4677-2021, https://doi.org/10.5194/acp-21-4677-2021, 2021
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We compare modelled near-surface pollutants with surface and satellite observations to better understand the controls on the regional concentrations of pollution in western Siberia for late spring and summer in 2011. We find two commonly used emission inventories underestimate human emissions when compared to observations. Transport emissions are the main source of pollutants within the region during this period, whilst fire emissions peak during June and are only significant south of 60° N.
Clémence Rose, Matti P. Rissanen, Siddharth Iyer, Jonathan Duplissy, Chao Yan, John B. Nowak, Aurélie Colomb, Régis Dupuy, Xu-Cheng He, Janne Lampilahti, Yee Jun Tham, Daniela Wimmer, Jean-Marc Metzger, Pierre Tulet, Jérôme Brioude, Céline Planche, Markku Kulmala, and Karine Sellegri
Atmos. Chem. Phys., 21, 4541–4560, https://doi.org/10.5194/acp-21-4541-2021, https://doi.org/10.5194/acp-21-4541-2021, 2021
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Sulfuric acid (H2SO4) is commonly accepted as a key precursor for atmospheric new particle formation. However, direct measurements of [H2SO4] remain challenging, motivating the development of proxies. Using data collected in two different volcanic plumes, we show, under these specific conditions, the good performance of a proxy from the literature and also highlight the benefit of the newly developed proxies for the prediction of the highest [H2SO4] values.
Haiyan Li, Manjula R. Canagaratna, Matthieu Riva, Pekka Rantala, Yanjun Zhang, Steven Thomas, Liine Heikkinen, Pierre-Marie Flaud, Eric Villenave, Emilie Perraudin, Douglas Worsnop, Markku Kulmala, Mikael Ehn, and Federico Bianchi
Atmos. Chem. Phys., 21, 4123–4147, https://doi.org/10.5194/acp-21-4123-2021, https://doi.org/10.5194/acp-21-4123-2021, 2021
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For the first time, we performed binPMF analysis on the complex mass spectra acquired with the Vocus PTR-TOF in two European pine forests and identified various primary emission sources and secondary oxidation processes of atmospheric organic vapors, i.e., terpenes and their oxidation products, with varying oxidation degrees. Further insights were gained regarding monoterpene and sesquiterpene reactions based on the interpretation results.
Julia Schneider, Kristina Höhler, Paavo Heikkilä, Jorma Keskinen, Barbara Bertozzi, Pia Bogert, Tobias Schorr, Nsikanabasi Silas Umo, Franziska Vogel, Zoé Brasseur, Yusheng Wu, Simo Hakala, Jonathan Duplissy, Dmitri Moisseev, Markku Kulmala, Michael P. Adams, Benjamin J. Murray, Kimmo Korhonen, Liqing Hao, Erik S. Thomson, Dimitri Castarède, Thomas Leisner, Tuukka Petäjä, and Ottmar Möhler
Atmos. Chem. Phys., 21, 3899–3918, https://doi.org/10.5194/acp-21-3899-2021, https://doi.org/10.5194/acp-21-3899-2021, 2021
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By triggering the formation of ice crystals, ice-nucleating particles (INP) strongly influence cloud formation. Continuous, long-term measurements are needed to characterize the atmospheric INP variability. Here, a first long-term time series of INP spectra measured in the boreal forest for more than 1 year is presented, showing a clear seasonal cycle. It is shown that the seasonal dependency of INP concentrations and prevalent INP types is driven by the abundance of biogenic aerosol.
Dimitrios Bousiotis, James Brean, Francis D. Pope, Manuel Dall'Osto, Xavier Querol, Andrés Alastuey, Noemi Perez, Tuukka Petäjä, Andreas Massling, Jacob Klenø Nøjgaard, Claus Nordstrøm, Giorgos Kouvarakis, Stergios Vratolis, Konstantinos Eleftheriadis, Jarkko V. Niemi, Harri Portin, Alfred Wiedensohler, Kay Weinhold, Maik Merkel, Thomas Tuch, and Roy M. Harrison
Atmos. Chem. Phys., 21, 3345–3370, https://doi.org/10.5194/acp-21-3345-2021, https://doi.org/10.5194/acp-21-3345-2021, 2021
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New particle formation events from 16 sites over Europe have been studied, and the influence of meteorological and atmospheric composition variables has been investigated. Some variables, like solar radiation intensity and temperature, have a positive effect on the occurrence of these events, while others have a negative effect, affecting different aspects such as the rate at which particles are formed or grow. This effect varies depending on the site type and magnitude of these variables.
Imre Salma, Wanda Thén, Pasi Aalto, Veli-Matti Kerminen, Anikó Kern, Zoltán Barcza, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 21, 2861–2880, https://doi.org/10.5194/acp-21-2861-2021, https://doi.org/10.5194/acp-21-2861-2021, 2021
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The distribution of the monthly mean nucleation frequency possessed a characteristic pattern. Its shape was compared to those of environmental variables, including vegetation-derived properties. The spring maximum in the occurrence frequency often overlapped with the positive T anomaly. The link between the heat stress and the occurrence minimum in summer could not be proven, whereas an association between the occurrence frequency and vegetation growth dynamics was clearly identified in spring.
Runlong Cai, Chao Yan, Dongsen Yang, Rujing Yin, Yiqun Lu, Chenjuan Deng, Yueyun Fu, Jiaxin Ruan, Xiaoxiao Li, Jenni Kontkanen, Qiang Zhang, Juha Kangasluoma, Yan Ma, Jiming Hao, Douglas R. Worsnop, Federico Bianchi, Pauli Paasonen, Veli-Matti Kerminen, Yongchun Liu, Lin Wang, Jun Zheng, Markku Kulmala, and Jingkun Jiang
Atmos. Chem. Phys., 21, 2457–2468, https://doi.org/10.5194/acp-21-2457-2021, https://doi.org/10.5194/acp-21-2457-2021, 2021
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Based on long-term measurements, we discovered that the collision of H2SO4–amine clusters is the governing mechanism that initializes fast new particle formation in the polluted atmospheric environment of urban Beijing. The mechanism and the governing factors for H2SO4–amine nucleation in the polluted atmosphere are quantitatively investigated in this study.
Runlong Cai, Chenxi Li, Xu-Cheng He, Chenjuan Deng, Yiqun Lu, Rujing Yin, Chao Yan, Lin Wang, Jingkun Jiang, Markku Kulmala, and Juha Kangasluoma
Atmos. Chem. Phys., 21, 2287–2304, https://doi.org/10.5194/acp-21-2287-2021, https://doi.org/10.5194/acp-21-2287-2021, 2021
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Growth rate determines the survival probability of atmospheric new particles and hence their impacts. We clarify the impacts of coagulation on the values retrieved by the appearance time method, which is widely used for growth rate evaluation. A new formula with coagulation correction is proposed based on derivation and tested using both models and atmospheric data. We show that the sub-3 nm particle growth rate in polluted environments may be overestimated without the coagulation correction.
Krista Luoma, Jarkko V. Niemi, Minna Aurela, Pak Lun Fung, Aku Helin, Tareq Hussein, Leena Kangas, Anu Kousa, Topi Rönkkö, Hilkka Timonen, Aki Virkkula, and Tuukka Petäjä
Atmos. Chem. Phys., 21, 1173–1189, https://doi.org/10.5194/acp-21-1173-2021, https://doi.org/10.5194/acp-21-1173-2021, 2021
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This study combined black carbon measurements from 15 Finnish sites that represented different environments (traffic, detached housing area, urban background, and regional background). The seasonal and diurnal variations in the black carbon concentration were associated with local emissions from traffic and residential wood burning. The study observed decreasing trends in the black carbon concentration and associated them with decreases in traffic emissions.
Jan Pisek, Angela Erb, Lauri Korhonen, Tobias Biermann, Arnaud Carrara, Edoardo Cremonese, Matthias Cuntz, Silvano Fares, Giacomo Gerosa, Thomas Grünwald, Niklas Hase, Michal Heliasz, Andreas Ibrom, Alexander Knohl, Johannes Kobler, Bart Kruijt, Holger Lange, Leena Leppänen, Jean-Marc Limousin, Francisco Ramon Lopez Serrano, Denis Loustau, Petr Lukeš, Lars Lundin, Riccardo Marzuoli, Meelis Mölder, Leonardo Montagnani, Johan Neirynck, Matthias Peichl, Corinna Rebmann, Eva Rubio, Margarida Santos-Reis, Crystal Schaaf, Marius Schmidt, Guillaume Simioni, Kamel Soudani, and Caroline Vincke
Biogeosciences, 18, 621–635, https://doi.org/10.5194/bg-18-621-2021, https://doi.org/10.5194/bg-18-621-2021, 2021
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Understory vegetation is the most diverse, least understood component of forests worldwide. Understory communities are important drivers of overstory succession and nutrient cycling. Multi-angle remote sensing enables us to describe surface properties by means that are not possible when using mono-angle data. Evaluated over an extensive set of forest ecosystem experimental sites in Europe, our reported method can deliver good retrievals, especially over different forest types with open canopies.
Tamara Emmerichs, Astrid Kerkweg, Huug Ouwersloot, Silvano Fares, Ivan Mammarella, and Domenico Taraborrelli
Geosci. Model Dev., 14, 495–519, https://doi.org/10.5194/gmd-14-495-2021, https://doi.org/10.5194/gmd-14-495-2021, 2021
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Dry deposition to vegetation is a major sink of ground-level ozone. Its parameterization in atmospheric chemistry models represents a significant source of uncertainty for global tropospheric ozone. We extended the current model parameterization with a relevant pathway and important meteorological adjustment factors. The comparison with measurements shows that this enables a more realistic model representation of ozone dry deposition velocity. Globally, annual dry deposition loss increases.
Juha Sulo, Nina Sarnela, Jenni Kontkanen, Lauri Ahonen, Pauli Paasonen, Tiia Laurila, Tuija Jokinen, Juha Kangasluoma, Heikki Junninen, Mikko Sipilä, Tuukka Petäjä, Markku Kulmala, and Katrianne Lehtipalo
Atmos. Chem. Phys., 21, 695–715, https://doi.org/10.5194/acp-21-695-2021, https://doi.org/10.5194/acp-21-695-2021, 2021
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In this study, we analyzed over 5 years of sub-3 nm particle concentrations and their precursor vapors, identifying atmoshperic vapors important to the formation of these particles in the boreal forest. We also observed seasonal differences in both particle and precursor vapor concentrations and the formation pathways of these particles. Our results confirm the importance of organic vapors in atmospheric aerosol formation and highlight key seasonal differences that require further study.
Oleg Sizov, Ekaterina Ezhova, Petr Tsymbarovich, Andrey Soromotin, Nikolay Prihod'ko, Tuukka Petäjä, Sergej Zilitinkevich, Markku Kulmala, Jaana Bäck, and Kajar Köster
Biogeosciences, 18, 207–228, https://doi.org/10.5194/bg-18-207-2021, https://doi.org/10.5194/bg-18-207-2021, 2021
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In changing climate, tundra is expected to turn into shrubs and trees, diminishing reindeer pasture and increasing risks of tick-borne diseases. However, this transition may require a disturbance. Fires in Siberia are increasingly widespread. We studied wildfire dynamics and tundra–forest transition over 60 years in northwest Siberia near the Arctic Circle. Based on satellite data analysis, we found that transition occurs in 40 %–85 % of burned tundra compared to 5 %–15 % in non-disturbed areas.
Wim Verbruggen, Guy Schurgers, Stéphanie Horion, Jonas Ardö, Paulo N. Bernardino, Bernard Cappelaere, Jérôme Demarty, Rasmus Fensholt, Laurent Kergoat, Thomas Sibret, Torbern Tagesson, and Hans Verbeeck
Biogeosciences, 18, 77–93, https://doi.org/10.5194/bg-18-77-2021, https://doi.org/10.5194/bg-18-77-2021, 2021
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A large part of Earth's land surface is covered by dryland ecosystems, which are subject to climate extremes that are projected to increase under future climate scenarios. By using a mathematical vegetation model, we studied the impact of single years of extreme rainfall on the vegetation in the Sahel. We found a contrasting response of grasses and trees to these extremes, strongly dependent on the way precipitation is spread over the rainy season, as well as a long-term impact on CO2 uptake.
Camille Yver-Kwok, Carole Philippon, Peter Bergamaschi, Tobias Biermann, Francescopiero Calzolari, Huilin Chen, Sebastien Conil, Paolo Cristofanelli, Marc Delmotte, Juha Hatakka, Michal Heliasz, Ove Hermansen, Kateřina Komínková, Dagmar Kubistin, Nicolas Kumps, Olivier Laurent, Tuomas Laurila, Irene Lehner, Janne Levula, Matthias Lindauer, Morgan Lopez, Ivan Mammarella, Giovanni Manca, Per Marklund, Jean-Marc Metzger, Meelis Mölder, Stephen M. Platt, Michel Ramonet, Leonard Rivier, Bert Scheeren, Mahesh Kumar Sha, Paul Smith, Martin Steinbacher, Gabriela Vítková, and Simon Wyss
Atmos. Meas. Tech., 14, 89–116, https://doi.org/10.5194/amt-14-89-2021, https://doi.org/10.5194/amt-14-89-2021, 2021
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The Integrated Carbon Observation System (ICOS) is a pan-European research infrastructure which provides harmonized and high-precision scientific data on the carbon cycle and the greenhouse gas (GHG) budget. All stations have to undergo a rigorous assessment before being labeled, i.e., receiving approval to join the network. In this paper, we present the labeling process for the ICOS atmospheric network through the 23 stations that were labeled between November 2017 and November 2019.
Helmi-Marja Keskinen, Ilona Ylivinkka, Liine Heikkinen, Pasi P. Aalto, Tuomo Nieminen, Katrianne Lehtipalo, Juho Aalto, Janne Levula, Jutta Kesti, Lauri R. Ahonen, Ekaterina Ezhova, Markku Kulmala, and Tuukka Petäjä
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-447, https://doi.org/10.5194/amt-2020-447, 2020
Publication in AMT not foreseen
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Long-term (2005–2017) aerosol particulate matter (PM) concentration measurements at Finland at Station for Measuring Ecosystem-Atmosphere Relations (SMEAR II, Hyytiälä) have been measured with three different measurement equipment. The comparison revealed an equivalence among the three methods. Mass concentrations were generally highest in summer. The descending trend was visible here in spring, summer and winter. This might have resulted at least partly from air quality legislation.
Toni Viskari, Maisa Laine, Liisa Kulmala, Jarmo Mäkelä, Istem Fer, and Jari Liski
Geosci. Model Dev., 13, 5959–5971, https://doi.org/10.5194/gmd-13-5959-2020, https://doi.org/10.5194/gmd-13-5959-2020, 2020
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The research here established whether a Bayesian statistical method called state data assimilation could be used to improve soil organic carbon (SOC) forecasts. Our test case was a fallow experiment where SOC content was measured over several decades from a plot where all vegetation was removed. Our results showed that state data assimilation improved projections and allowed for the detailed model state be updated with coarse total carbon measurements.
Jingsha Xu, Shaojie Song, Roy M. Harrison, Congbo Song, Lianfang Wei, Qiang Zhang, Yele Sun, Lu Lei, Chao Zhang, Xiaohong Yao, Dihui Chen, Weijun Li, Miaomiao Wu, Hezhong Tian, Lining Luo, Shengrui Tong, Weiran Li, Junling Wang, Guoliang Shi, Yanqi Huangfu, Yingze Tian, Baozhu Ge, Shaoli Su, Chao Peng, Yang Chen, Fumo Yang, Aleksandra Mihajlidi-Zelić, Dragana Đorđević, Stefan J. Swift, Imogen Andrews, Jacqueline F. Hamilton, Ye Sun, Agung Kramawijaya, Jinxiu Han, Supattarachai Saksakulkrai, Clarissa Baldo, Siqi Hou, Feixue Zheng, Kaspar R. Daellenbach, Chao Yan, Yongchun Liu, Markku Kulmala, Pingqing Fu, and Zongbo Shi
Atmos. Meas. Tech., 13, 6325–6341, https://doi.org/10.5194/amt-13-6325-2020, https://doi.org/10.5194/amt-13-6325-2020, 2020
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An interlaboratory comparison was conducted for the first time to examine differences in water-soluble inorganic ions (WSIIs) measured by 10 labs using ion chromatography (IC) and by two online aerosol chemical speciation monitor (ACSM) methods. Major ions including SO42−, NO3− and NH4+ agreed well in 10 IC labs and correlated well with ACSM data. WSII interlab variability strongly affected aerosol acidity results based on ion balance, but aerosol pH computed by ISORROPIA II was very similar.
Juan Andrés Casquero-Vera, Hassan Lyamani, Lubna Dada, Simo Hakala, Pauli Paasonen, Roberto Román, Roberto Fraile, Tuukka Petäjä, Francisco José Olmo-Reyes, and Lucas Alados-Arboledas
Atmos. Chem. Phys., 20, 14253–14271, https://doi.org/10.5194/acp-20-14253-2020, https://doi.org/10.5194/acp-20-14253-2020, 2020
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New particle formation was investigated at two stations located close to each other but at different altitudes: urban and high-altitude sites. Results show that sulfuric acid is able to explain a minimal fraction contribution to the observed growth rates and point to the availability of volatile organic compounds as the main factor controlling NPF events at both sites. A closer analysis of the NPF events that were observed at high-altitude sites during a Saharan dust episode was carried out.
Yuan Zhang, Ana Bastos, Fabienne Maignan, Daniel Goll, Olivier Boucher, Laurent Li, Alessandro Cescatti, Nicolas Vuichard, Xiuzhi Chen, Christof Ammann, M. Altaf Arain, T. Andrew Black, Bogdan Chojnicki, Tomomichi Kato, Ivan Mammarella, Leonardo Montagnani, Olivier Roupsard, Maria J. Sanz, Lukas Siebicke, Marek Urbaniak, Francesco Primo Vaccari, Georg Wohlfahrt, Will Woodgate, and Philippe Ciais
Geosci. Model Dev., 13, 5401–5423, https://doi.org/10.5194/gmd-13-5401-2020, https://doi.org/10.5194/gmd-13-5401-2020, 2020
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We improved the ORCHIDEE LSM by distinguishing diffuse and direct light in canopy and evaluated the new model with observations from 159 sites. Compared with the old model, the new model has better sunny GPP and reproduced the diffuse light fertilization effect observed at flux sites. Our simulations also indicate different mechanisms causing the observed GPP enhancement under cloudy conditions at different times. The new model has the potential to study large-scale impacts of aerosol changes.
Yongchun Liu, Yusheng Zhang, Chaofan Lian, Chao Yan, Zeming Feng, Feixue Zheng, Xiaolong Fan, Yan Chen, Weigang Wang, Biwu Chu, Yonghong Wang, Jing Cai, Wei Du, Kaspar R. Daellenbach, Juha Kangasluoma, Federico Bianchi, Joni Kujansuu, Tuukka Petäjä, Xuefei Wang, Bo Hu, Yuesi Wang, Maofa Ge, Hong He, and Markku Kulmala
Atmos. Chem. Phys., 20, 13023–13040, https://doi.org/10.5194/acp-20-13023-2020, https://doi.org/10.5194/acp-20-13023-2020, 2020
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Understanding of the chemical and physical processes leading to atmospheric aerosol particle formation is crucial to devising effective mitigation strategies to protect the public and reduce uncertainties in climate predictions. We found that the photolysis of nitrous acid could promote the formation of organic and nitrate aerosol and that traffic-related emission is a major contributor to ambient nitrous acid on haze days in wintertime in Beijing.
Jing Cai, Biwu Chu, Lei Yao, Chao Yan, Liine M. Heikkinen, Feixue Zheng, Chang Li, Xiaolong Fan, Shaojun Zhang, Daoyuan Yang, Yonghong Wang, Tom V. Kokkonen, Tommy Chan, Ying Zhou, Lubna Dada, Yongchun Liu, Hong He, Pauli Paasonen, Joni T. Kujansuu, Tuukka Petäjä, Claudia Mohr, Juha Kangasluoma, Federico Bianchi, Yele Sun, Philip L. Croteau, Douglas R. Worsnop, Veli-Matti Kerminen, Wei Du, Markku Kulmala, and Kaspar R. Daellenbach
Atmos. Chem. Phys., 20, 12721–12740, https://doi.org/10.5194/acp-20-12721-2020, https://doi.org/10.5194/acp-20-12721-2020, 2020
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By applying both OA PMF and size PMF at the same urban measurement site in Beijing, similar particle source types, including vehicular emissions, cooking emissions and secondary formation-related sources, were resolved by both frameworks and agreed well. It is also found that in the absence of new particle formation, vehicular and cooking emissions dominate the particle number concentration, while secondary particulate matter governed PM2.5 mass during spring and summer in Beijing.
Ilona Ylivinkka, Santeri Kaupinmäki, Meri Virman, Maija Peltola, Ditte Taipale, Tuukka Petäjä, Veli-Matti Kerminen, Markku Kulmala, and Ekaterina Ezhova
Atmos. Meas. Tech., 13, 5595–5619, https://doi.org/10.5194/amt-13-5595-2020, https://doi.org/10.5194/amt-13-5595-2020, 2020
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In this study, we developed a new algorithm for cloud classification using solar radiation and cloud base height measurements. Our objective was to develop a simple and inexpensive but effective algorithm for the needs of studies related to ecosystem and atmosphere interactions. In the present study, we used the algorithm for obtaining cloud statistics at a measurement station in southern Finland, and we discuss the advantages and shortcomings of the algorithm.
Janne Lampilahti, Hanna Elina Manninen, Katri Leino, Riikka Väänänen, Antti Manninen, Stephany Buenrostro Mazon, Tuomo Nieminen, Matti Leskinen, Joonas Enroth, Marja Bister, Sergej Zilitinkevich, Juha Kangasluoma, Heikki Järvinen, Veli-Matti Kerminen, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 20, 11841–11854, https://doi.org/10.5194/acp-20-11841-2020, https://doi.org/10.5194/acp-20-11841-2020, 2020
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In this work, by using co-located airborne and ground-based measurements, we show that counter-rotating horizontal circulations in the planetary boundary layer (roll vortices) frequently enhance regional new particle formation or induce localized bursts of new particle formation. These observations can be explained by the ability of the rolls to efficiently lift low-volatile vapors emitted from the surface to the top of the boundary layer where new particle formation is more favorable.
Martin Heinritzi, Lubna Dada, Mario Simon, Dominik Stolzenburg, Andrea C. Wagner, Lukas Fischer, Lauri R. Ahonen, Stavros Amanatidis, Rima Baalbaki, Andrea Baccarini, Paulus S. Bauer, Bernhard Baumgartner, Federico Bianchi, Sophia Brilke, Dexian Chen, Randall Chiu, Antonio Dias, Josef Dommen, Jonathan Duplissy, Henning Finkenzeller, Carla Frege, Claudia Fuchs, Olga Garmash, Hamish Gordon, Manuel Granzin, Imad El Haddad, Xucheng He, Johanna Helm, Victoria Hofbauer, Christopher R. Hoyle, Juha Kangasluoma, Timo Keber, Changhyuk Kim, Andreas Kürten, Houssni Lamkaddam, Tiia M. Laurila, Janne Lampilahti, Chuan Ping Lee, Katrianne Lehtipalo, Markus Leiminger, Huajun Mai, Vladimir Makhmutov, Hanna Elina Manninen, Ruby Marten, Serge Mathot, Roy Lee Mauldin, Bernhard Mentler, Ugo Molteni, Tatjana Müller, Wei Nie, Tuomo Nieminen, Antti Onnela, Eva Partoll, Monica Passananti, Tuukka Petäjä, Joschka Pfeifer, Veronika Pospisilova, Lauriane L. J. Quéléver, Matti P. Rissanen, Clémence Rose, Siegfried Schobesberger, Wiebke Scholz, Kay Scholze, Mikko Sipilä, Gerhard Steiner, Yuri Stozhkov, Christian Tauber, Yee Jun Tham, Miguel Vazquez-Pufleau, Annele Virtanen, Alexander L. Vogel, Rainer Volkamer, Robert Wagner, Mingyi Wang, Lena Weitz, Daniela Wimmer, Mao Xiao, Chao Yan, Penglin Ye, Qiaozhi Zha, Xueqin Zhou, Antonio Amorim, Urs Baltensperger, Armin Hansel, Markku Kulmala, António Tomé, Paul M. Winkler, Douglas R. Worsnop, Neil M. Donahue, Jasper Kirkby, and Joachim Curtius
Atmos. Chem. Phys., 20, 11809–11821, https://doi.org/10.5194/acp-20-11809-2020, https://doi.org/10.5194/acp-20-11809-2020, 2020
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With experiments performed at CLOUD, we show how isoprene interferes in monoterpene oxidation via RO2 termination at atmospherically relevant concentrations. This interference shifts the distribution of highly oxygenated organic molecules (HOMs) away from C20 class dimers towards C15 class dimers, which subsequently reduces both biogenic nucleation and early growth rates. Our results may help to understand the absence of new-particle formation in isoprene-rich environments.
Lubna Dada, Ilona Ylivinkka, Rima Baalbaki, Chang Li, Yishuo Guo, Chao Yan, Lei Yao, Nina Sarnela, Tuija Jokinen, Kaspar R. Daellenbach, Rujing Yin, Chenjuan Deng, Biwu Chu, Tuomo Nieminen, Yonghong Wang, Zhuohui Lin, Roseline C. Thakur, Jenni Kontkanen, Dominik Stolzenburg, Mikko Sipilä, Tareq Hussein, Pauli Paasonen, Federico Bianchi, Imre Salma, Tamás Weidinger, Michael Pikridas, Jean Sciare, Jingkun Jiang, Yongchun Liu, Tuukka Petäjä, Veli-Matti Kerminen, and Markku Kulmala
Atmos. Chem. Phys., 20, 11747–11766, https://doi.org/10.5194/acp-20-11747-2020, https://doi.org/10.5194/acp-20-11747-2020, 2020
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We rely on sulfuric acid measurements in four contrasting environments, Hyytiälä, Finland; Agia Marina, Cyprus; Budapest, Hungary; and Beijing, China, representing semi-pristine boreal forest, rural environment in the Mediterranean area, urban environment, and heavily polluted megacity, respectively, in order to define the sources and sinks of sulfuric acid in these environments and to derive a new sulfuric acid proxy to be utilized in locations and during periods when it is not measured.
Jenni Kontkanen, Chenjuan Deng, Yueyun Fu, Lubna Dada, Ying Zhou, Jing Cai, Kaspar R. Daellenbach, Simo Hakala, Tom V. Kokkonen, Zhuohui Lin, Yongchun Liu, Yonghong Wang, Chao Yan, Tuukka Petäjä, Jingkun Jiang, Markku Kulmala, and Pauli Paasonen
Atmos. Chem. Phys., 20, 11329–11348, https://doi.org/10.5194/acp-20-11329-2020, https://doi.org/10.5194/acp-20-11329-2020, 2020
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To estimate the impacts of atmospheric aerosol particles on air quality, knowledge of size distributions of particles emitted from anthropogenic sources is needed. We introduce a new method for determining size-resolved particle number emissions from measured particle size distributions. We apply our method to data measured in Beijing, China. We find that particle number emissions at our site are dominated by emissions of particles smaller than 30 nm, originating mainly from traffic.
Konstantinos-Matthaios Doulgeris, Mika Komppula, Sami Romakkaniemi, Antti-Pekka Hyvärinen, Veli-Matti Kerminen, and David Brus
Atmos. Meas. Tech., 13, 5129–5147, https://doi.org/10.5194/amt-13-5129-2020, https://doi.org/10.5194/amt-13-5129-2020, 2020
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We intercompared three cloud spectrometers ground setups in conditions with frequently occurring supercooled clouds. The measurements were conducted during the Pallas Cloud Experiment (PaCE) in 2013, in the Finnish sub-Arctic region at Sammaltunturi station. The main meteorological parameters influencing the spectrometers' performance was the wind direction. Final recommendations and our view on the main limitations of each spectrometer ground setup are presented.
Arnaud P. Praplan, Toni Tykkä, Simon Schallhart, Virpi Tarvainen, Jaana Bäck, and Heidi Hellén
Biogeosciences, 17, 4681–4705, https://doi.org/10.5194/bg-17-4681-2020, https://doi.org/10.5194/bg-17-4681-2020, 2020
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In this paper, we study emissions of volatile organic compounds (VOCs) from three boreal tree species. Individual compounds are quantified with on-line separation analytical techniques, while the total reactivity of the emissions is measured using a custom-built instrument. On some occasions, in particular when the trees suffer from stress, the total reactivity measured is higher than the sum of the reactivity of individual compounds. This indicates that the threes emit VOCs that remain unknown.
Tommy Chan, Runlong Cai, Lauri R. Ahonen, Yiliang Liu, Ying Zhou, Joonas Vanhanen, Lubna Dada, Yan Chao, Yongchun Liu, Lin Wang, Markku Kulmala, and Juha Kangasluoma
Atmos. Meas. Tech., 13, 4885–4898, https://doi.org/10.5194/amt-13-4885-2020, https://doi.org/10.5194/amt-13-4885-2020, 2020
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Using a particle size magnifier (PSM; Airmodus, Finland), we determined the particle size distribution using four inversion methods and compared each method to the others to establish their strengths and weaknesses. Furthermore, we provided a step-by-step procedure on how to invert measured data using the PSM. Finally, we provided recommendations, code and data related to the data inversion. This is an important paper, as no operating procedure exists regarding how to process measured PSM data.
Paolo Laj, Alessandro Bigi, Clémence Rose, Elisabeth Andrews, Cathrine Lund Myhre, Martine Collaud Coen, Yong Lin, Alfred Wiedensohler, Michael Schulz, John A. Ogren, Markus Fiebig, Jonas Gliß, Augustin Mortier, Marco Pandolfi, Tuukka Petäja, Sang-Woo Kim, Wenche Aas, Jean-Philippe Putaud, Olga Mayol-Bracero, Melita Keywood, Lorenzo Labrador, Pasi Aalto, Erik Ahlberg, Lucas Alados Arboledas, Andrés Alastuey, Marcos Andrade, Begoña Artíñano, Stina Ausmeel, Todor Arsov, Eija Asmi, John Backman, Urs Baltensperger, Susanne Bastian, Olaf Bath, Johan Paul Beukes, Benjamin T. Brem, Nicolas Bukowiecki, Sébastien Conil, Cedric Couret, Derek Day, Wan Dayantolis, Anna Degorska, Konstantinos Eleftheriadis, Prodromos Fetfatzis, Olivier Favez, Harald Flentje, Maria I. Gini, Asta Gregorič, Martin Gysel-Beer, A. Gannet Hallar, Jenny Hand, Andras Hoffer, Christoph Hueglin, Rakesh K. Hooda, Antti Hyvärinen, Ivo Kalapov, Nikos Kalivitis, Anne Kasper-Giebl, Jeong Eun Kim, Giorgos Kouvarakis, Irena Kranjc, Radovan Krejci, Markku Kulmala, Casper Labuschagne, Hae-Jung Lee, Heikki Lihavainen, Neng-Huei Lin, Gunter Löschau, Krista Luoma, Angela Marinoni, Sebastiao Martins Dos Santos, Frank Meinhardt, Maik Merkel, Jean-Marc Metzger, Nikolaos Mihalopoulos, Nhat Anh Nguyen, Jakub Ondracek, Noemi Pérez, Maria Rita Perrone, Jean-Eudes Petit, David Picard, Jean-Marc Pichon, Veronique Pont, Natalia Prats, Anthony Prenni, Fabienne Reisen, Salvatore Romano, Karine Sellegri, Sangeeta Sharma, Gerhard Schauer, Patrick Sheridan, James Patrick Sherman, Maik Schütze, Andreas Schwerin, Ralf Sohmer, Mar Sorribas, Martin Steinbacher, Junying Sun, Gloria Titos, Barbara Toczko, Thomas Tuch, Pierre Tulet, Peter Tunved, Ville Vakkari, Fernando Velarde, Patricio Velasquez, Paolo Villani, Sterios Vratolis, Sheng-Hsiang Wang, Kay Weinhold, Rolf Weller, Margarita Yela, Jesus Yus-Diez, Vladimir Zdimal, Paul Zieger, and Nadezda Zikova
Atmos. Meas. Tech., 13, 4353–4392, https://doi.org/10.5194/amt-13-4353-2020, https://doi.org/10.5194/amt-13-4353-2020, 2020
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The paper establishes the fiducial reference of the GAW aerosol network providing the fully characterized value chain to the provision of four climate-relevant aerosol properties from ground-based sites. Data from almost 90 stations worldwide are reported for a reference year, 2017, providing a unique and very robust view of the variability of these variables worldwide. Current gaps in the GAW network are analysed and requirements for the Global Climate Monitoring System are proposed.
Mario Simon, Lubna Dada, Martin Heinritzi, Wiebke Scholz, Dominik Stolzenburg, Lukas Fischer, Andrea C. Wagner, Andreas Kürten, Birte Rörup, Xu-Cheng He, João Almeida, Rima Baalbaki, Andrea Baccarini, Paulus S. Bauer, Lisa Beck, Anton Bergen, Federico Bianchi, Steffen Bräkling, Sophia Brilke, Lucia Caudillo, Dexian Chen, Biwu Chu, António Dias, Danielle C. Draper, Jonathan Duplissy, Imad El-Haddad, Henning Finkenzeller, Carla Frege, Loic Gonzalez-Carracedo, Hamish Gordon, Manuel Granzin, Jani Hakala, Victoria Hofbauer, Christopher R. Hoyle, Changhyuk Kim, Weimeng Kong, Houssni Lamkaddam, Chuan P. Lee, Katrianne Lehtipalo, Markus Leiminger, Huajun Mai, Hanna E. Manninen, Guillaume Marie, Ruby Marten, Bernhard Mentler, Ugo Molteni, Leonid Nichman, Wei Nie, Andrea Ojdanic, Antti Onnela, Eva Partoll, Tuukka Petäjä, Joschka Pfeifer, Maxim Philippov, Lauriane L. J. Quéléver, Ananth Ranjithkumar, Matti P. Rissanen, Simon Schallhart, Siegfried Schobesberger, Simone Schuchmann, Jiali Shen, Mikko Sipilä, Gerhard Steiner, Yuri Stozhkov, Christian Tauber, Yee J. Tham, António R. Tomé, Miguel Vazquez-Pufleau, Alexander L. Vogel, Robert Wagner, Mingyi Wang, Dongyu S. Wang, Yonghong Wang, Stefan K. Weber, Yusheng Wu, Mao Xiao, Chao Yan, Penglin Ye, Qing Ye, Marcel Zauner-Wieczorek, Xueqin Zhou, Urs Baltensperger, Josef Dommen, Richard C. Flagan, Armin Hansel, Markku Kulmala, Rainer Volkamer, Paul M. Winkler, Douglas R. Worsnop, Neil M. Donahue, Jasper Kirkby, and Joachim Curtius
Atmos. Chem. Phys., 20, 9183–9207, https://doi.org/10.5194/acp-20-9183-2020, https://doi.org/10.5194/acp-20-9183-2020, 2020
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Highly oxygenated organic compounds (HOMs) have been identified as key vapors involved in atmospheric new-particle formation (NPF). The molecular distribution, HOM yield, and NPF from α-pinene oxidation experiments were measured at the CLOUD chamber over a wide tropospheric-temperature range. This study shows on a molecular scale that despite the sharp reduction in HOM yield at lower temperatures, the reduced volatility counteracts this effect and leads to an overall increase in the NPF rate.
Kukka-Maaria Kohonen, Pasi Kolari, Linda M. J. Kooijmans, Huilin Chen, Ulli Seibt, Wu Sun, and Ivan Mammarella
Atmos. Meas. Tech., 13, 3957–3975, https://doi.org/10.5194/amt-13-3957-2020, https://doi.org/10.5194/amt-13-3957-2020, 2020
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Biosphere–atmosphere gas exchange (flux) measurements of carbonyl sulfide (COS) are becoming popular for estimating biospheric photosynthesis. To compare COS flux measurements across different measurement sites, we need standardized protocols for data processing. We analyze how various data processing steps affect the calculated COS flux and how they differ from carbon dioxide (CO2) flux processing steps, and we aim to settle on a set of recommended protocols for COS flux calculation.
Tuukka Petäjä, Ella-Maria Duplissy, Ksenia Tabakova, Julia Schmale, Barbara Altstädter, Gerard Ancellet, Mikhail Arshinov, Yurii Balin, Urs Baltensperger, Jens Bange, Alison Beamish, Boris Belan, Antoine Berchet, Rossana Bossi, Warren R. L. Cairns, Ralf Ebinghaus, Imad El Haddad, Beatriz Ferreira-Araujo, Anna Franck, Lin Huang, Antti Hyvärinen, Angelika Humbert, Athina-Cerise Kalogridis, Pavel Konstantinov, Astrid Lampert, Matthew MacLeod, Olivier Magand, Alexander Mahura, Louis Marelle, Vladimir Masloboev, Dmitri Moisseev, Vaios Moschos, Niklas Neckel, Tatsuo Onishi, Stefan Osterwalder, Aino Ovaska, Pauli Paasonen, Mikhail Panchenko, Fidel Pankratov, Jakob B. Pernov, Andreas Platis, Olga Popovicheva, Jean-Christophe Raut, Aurélie Riandet, Torsten Sachs, Rosamaria Salvatori, Roberto Salzano, Ludwig Schröder, Martin Schön, Vladimir Shevchenko, Henrik Skov, Jeroen E. Sonke, Andrea Spolaor, Vasileios K. Stathopoulos, Mikko Strahlendorff, Jennie L. Thomas, Vito Vitale, Sterios Vratolis, Carlo Barbante, Sabine Chabrillat, Aurélien Dommergue, Konstantinos Eleftheriadis, Jyri Heilimo, Kathy S. Law, Andreas Massling, Steffen M. Noe, Jean-Daniel Paris, André S. H. Prévôt, Ilona Riipinen, Birgit Wehner, Zhiyong Xie, and Hanna K. Lappalainen
Atmos. Chem. Phys., 20, 8551–8592, https://doi.org/10.5194/acp-20-8551-2020, https://doi.org/10.5194/acp-20-8551-2020, 2020
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The role of polar regions is increasing in terms of megatrends such as globalization, new transport routes, demography, and the use of natural resources with consequent effects on regional and transported pollutant concentrations. Here we summarize initial results from our integrative project exploring the Arctic environment and pollution to deliver data products, metrics, and indicators for stakeholders.
Yuan Yang, Yonghong Wang, Putian Zhou, Dan Yao, Dongsheng Ji, Jie Sun, Yinghong Wang, Shuman Zhao, Wei Huang, Shuanghong Yang, Dean Chen, Wenkang Gao, Zirui Liu, Bo Hu, Renjian Zhang, Limin Zeng, Maofa Ge, Tuukka Petäjä, Veli-Matti Kerminen, Markku Kulmala, and Yuesi Wang
Atmos. Chem. Phys., 20, 8181–8200, https://doi.org/10.5194/acp-20-8181-2020, https://doi.org/10.5194/acp-20-8181-2020, 2020
Xuefei Li, Outi Wahlroos, Sami Haapanala, Jukka Pumpanen, Harri Vasander, Anne Ojala, Timo Vesala, and Ivan Mammarella
Biogeosciences, 17, 3409–3425, https://doi.org/10.5194/bg-17-3409-2020, https://doi.org/10.5194/bg-17-3409-2020, 2020
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We measured CO2 and CH4 fluxes and quantified the global warming potential of different surface areas in a recently created urban wetland in Southern Finland. The ecosystem has a small net climate warming effect which was mainly contributed by the open-water areas. Our results suggest that limiting open-water areas and setting a design preference for areas of emergent vegetation in the establishment of urban wetlands can be a beneficial practice when considering solely the climate impact.
Dominik Stolzenburg, Mario Simon, Ananth Ranjithkumar, Andreas Kürten, Katrianne Lehtipalo, Hamish Gordon, Sebastian Ehrhart, Henning Finkenzeller, Lukas Pichelstorfer, Tuomo Nieminen, Xu-Cheng He, Sophia Brilke, Mao Xiao, António Amorim, Rima Baalbaki, Andrea Baccarini, Lisa Beck, Steffen Bräkling, Lucía Caudillo Murillo, Dexian Chen, Biwu Chu, Lubna Dada, António Dias, Josef Dommen, Jonathan Duplissy, Imad El Haddad, Lukas Fischer, Loic Gonzalez Carracedo, Martin Heinritzi, Changhyuk Kim, Theodore K. Koenig, Weimeng Kong, Houssni Lamkaddam, Chuan Ping Lee, Markus Leiminger, Zijun Li, Vladimir Makhmutov, Hanna E. Manninen, Guillaume Marie, Ruby Marten, Tatjana Müller, Wei Nie, Eva Partoll, Tuukka Petäjä, Joschka Pfeifer, Maxim Philippov, Matti P. Rissanen, Birte Rörup, Siegfried Schobesberger, Simone Schuchmann, Jiali Shen, Mikko Sipilä, Gerhard Steiner, Yuri Stozhkov, Christian Tauber, Yee Jun Tham, António Tomé, Miguel Vazquez-Pufleau, Andrea C. Wagner, Mingyi Wang, Yonghong Wang, Stefan K. Weber, Daniela Wimmer, Peter J. Wlasits, Yusheng Wu, Qing Ye, Marcel Zauner-Wieczorek, Urs Baltensperger, Kenneth S. Carslaw, Joachim Curtius, Neil M. Donahue, Richard C. Flagan, Armin Hansel, Markku Kulmala, Jos Lelieveld, Rainer Volkamer, Jasper Kirkby, and Paul M. Winkler
Atmos. Chem. Phys., 20, 7359–7372, https://doi.org/10.5194/acp-20-7359-2020, https://doi.org/10.5194/acp-20-7359-2020, 2020
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Sulfuric acid is a major atmospheric vapour for aerosol formation. If new particles grow fast enough, they can act as cloud droplet seeds or affect air quality. In a controlled laboratory set-up, we demonstrate that van der Waals forces enhance growth from sulfuric acid. We disentangle the effects of ammonia, ions and particle hydration, presenting a complete picture of sulfuric acid growth from molecular clusters onwards. In a climate model, we show its influence on the global aerosol budget.
Christopher P. O. Reyer, Ramiro Silveyra Gonzalez, Klara Dolos, Florian Hartig, Ylva Hauf, Matthias Noack, Petra Lasch-Born, Thomas Rötzer, Hans Pretzsch, Henning Meesenburg, Stefan Fleck, Markus Wagner, Andreas Bolte, Tanja G. M. Sanders, Pasi Kolari, Annikki Mäkelä, Timo Vesala, Ivan Mammarella, Jukka Pumpanen, Alessio Collalti, Carlo Trotta, Giorgio Matteucci, Ettore D'Andrea, Lenka Foltýnová, Jan Krejza, Andreas Ibrom, Kim Pilegaard, Denis Loustau, Jean-Marc Bonnefond, Paul Berbigier, Delphine Picart, Sébastien Lafont, Michael Dietze, David Cameron, Massimo Vieno, Hanqin Tian, Alicia Palacios-Orueta, Victor Cicuendez, Laura Recuero, Klaus Wiese, Matthias Büchner, Stefan Lange, Jan Volkholz, Hyungjun Kim, Joanna A. Horemans, Friedrich Bohn, Jörg Steinkamp, Alexander Chikalanov, Graham P. Weedon, Justin Sheffield, Flurin Babst, Iliusi Vega del Valle, Felicitas Suckow, Simon Martel, Mats Mahnken, Martin Gutsch, and Katja Frieler
Earth Syst. Sci. Data, 12, 1295–1320, https://doi.org/10.5194/essd-12-1295-2020, https://doi.org/10.5194/essd-12-1295-2020, 2020
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Process-based vegetation models are widely used to predict local and global ecosystem dynamics and climate change impacts. Due to their complexity, they require careful parameterization and evaluation to ensure that projections are accurate and reliable. The PROFOUND Database provides a wide range of empirical data to calibrate and evaluate vegetation models that simulate climate impacts at the forest stand scale to support systematic model intercomparisons and model development in Europe.
Mikhail Paramonov, Saskia Drossaart van Dusseldorp, Ellen Gute, Jonathan P. D. Abbatt, Paavo Heikkilä, Jorma Keskinen, Xuemeng Chen, Krista Luoma, Liine Heikkinen, Liqing Hao, Tuukka Petäjä, and Zamin A. Kanji
Atmos. Chem. Phys., 20, 6687–6706, https://doi.org/10.5194/acp-20-6687-2020, https://doi.org/10.5194/acp-20-6687-2020, 2020
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Ice-nucleating particle (INP) measurements were performed in the boreal environment of southern Finland in the winter–spring of 2018. It was found that no single parameter could be used to predict the INP number concentration at the measurement location during the examined time period. It was also not possible to identify physical and chemical properties of ambient INPs despite the complexity of the instrumental set-up. Therefore, this paper addresses the necessity for future INP measurements.
Dean Chen, Putian Zhou, Tuomo Nieminen, Pontus Roldin, Ximeng Qi, Petri Clusius, Carlton Xavier, Lukas Pichelstorfer, Markku Kulmala, Pekka Rantala, Juho Aalto, Nina Sarnela, Pasi Kolari, Petri Keronen, Matti P. Rissanen, Metin Baykara, and Michael Boy
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-128, https://doi.org/10.5194/acp-2020-128, 2020
Preprint withdrawn
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Atmospheric oxidants OH, O3 and NO3 dominate the atmospheric oxidation capacity, and sulfuric acid (H2SO4) is considered as a main driver for new particle formation events. We studied how the trends of these atmospheric oxidants and H2SO4 changed in southern Finland during the past 12 years and discussed how these trends related to decreasing emissions of air pollutants in Europe. Our results showed that OH increased by 1.56 % yr−1 at daytime and NO3 decreased by 3.92 % yr−1 at nighttime.
Laura Matkala, Maija Salemaa, and Jaana Bäck
Biogeosciences, 17, 1535–1556, https://doi.org/10.5194/bg-17-1535-2020, https://doi.org/10.5194/bg-17-1535-2020, 2020
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We studied how species number and abundance of the understorey vegetation correlates with nutrient contents of soil and tree leaves at a northern boreal forest site. The phosphorus (P) content of the humus layer showed higher correlation with vegetation than the nitrogen (N) content. Usually N is considered more important in boreal forests. The plots with high P content in humus had birch as the dominant tree species, implying that birch leaf litter is an important source of P to the plants.
Chris R. Flechard, Andreas Ibrom, Ute M. Skiba, Wim de Vries, Marcel van Oijen, David R. Cameron, Nancy B. Dise, Janne F. J. Korhonen, Nina Buchmann, Arnaud Legout, David Simpson, Maria J. Sanz, Marc Aubinet, Denis Loustau, Leonardo Montagnani, Johan Neirynck, Ivan A. Janssens, Mari Pihlatie, Ralf Kiese, Jan Siemens, André-Jean Francez, Jürgen Augustin, Andrej Varlagin, Janusz Olejnik, Radosław Juszczak, Mika Aurela, Daniel Berveiller, Bogdan H. Chojnicki, Ulrich Dämmgen, Nicolas Delpierre, Vesna Djuricic, Julia Drewer, Eric Dufrêne, Werner Eugster, Yannick Fauvel, David Fowler, Arnoud Frumau, André Granier, Patrick Gross, Yannick Hamon, Carole Helfter, Arjan Hensen, László Horváth, Barbara Kitzler, Bart Kruijt, Werner L. Kutsch, Raquel Lobo-do-Vale, Annalea Lohila, Bernard Longdoz, Michal V. Marek, Giorgio Matteucci, Marta Mitosinkova, Virginie Moreaux, Albrecht Neftel, Jean-Marc Ourcival, Kim Pilegaard, Gabriel Pita, Francisco Sanz, Jan K. Schjoerring, Maria-Teresa Sebastià, Y. Sim Tang, Hilde Uggerud, Marek Urbaniak, Netty van Dijk, Timo Vesala, Sonja Vidic, Caroline Vincke, Tamás Weidinger, Sophie Zechmeister-Boltenstern, Klaus Butterbach-Bahl, Eiko Nemitz, and Mark A. Sutton
Biogeosciences, 17, 1583–1620, https://doi.org/10.5194/bg-17-1583-2020, https://doi.org/10.5194/bg-17-1583-2020, 2020
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Experimental evidence from a network of 40 monitoring sites in Europe suggests that atmospheric nitrogen deposition to forests and other semi-natural vegetation impacts the carbon sequestration rates in ecosystems, as well as the net greenhouse gas balance including other greenhouse gases such as nitrous oxide and methane. Excess nitrogen deposition in polluted areas also leads to other environmental impacts such as nitrogen leaching to groundwater and other pollutant gaseous emissions.
Liine Heikkinen, Mikko Äijälä, Matthieu Riva, Krista Luoma, Kaspar Dällenbach, Juho Aalto, Pasi Aalto, Diego Aliaga, Minna Aurela, Helmi Keskinen, Ulla Makkonen, Pekka Rantala, Markku Kulmala, Tuukka Petäjä, Douglas Worsnop, and Mikael Ehn
Atmos. Chem. Phys., 20, 3151–3180, https://doi.org/10.5194/acp-20-3151-2020, https://doi.org/10.5194/acp-20-3151-2020, 2020
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Atmospheric aerosols are solid or liquid particles suspended in the air. They are known as a health risk, but they also influence the Earth's climate. The composition of aerosols becomes important when predicting their effect on climate. We show both seasonal and year-to-year variability of aerosol chemical composition in the boreal forest of Finland. We observed a consistent bimodal seasonal trend: a biogenic summertime maximum and an anthropogenic wintertime maximum in the mass concentration.
Haiyan Li, Matthieu Riva, Pekka Rantala, Liine Heikkinen, Kaspar Daellenbach, Jordan E. Krechmer, Pierre-Marie Flaud, Douglas Worsnop, Markku Kulmala, Eric Villenave, Emilie Perraudin, Mikael Ehn, and Federico Bianchi
Atmos. Chem. Phys., 20, 1941–1959, https://doi.org/10.5194/acp-20-1941-2020, https://doi.org/10.5194/acp-20-1941-2020, 2020
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We deployed the recently developed Vocus PTR-TOF in the French Landes forest during summertime to gain insights into terpene chemistry. In addition to isoprene, monoterpenes, sesquiterpenes, and the low-volatility diterpenes, various terpene reaction products are characterized. Through the analysis of terpene chemistry, we demonstrate the capability of the Vocus PTR-TOF for the detection of oxidized reaction products, highlighting its importance in investigating atmospheric oxidation processes.
Ditte Taipale, Juho Aalto, Pauliina Schiestl-Aalto, Markku Kulmala, and Jaana Bäck
Biogeosciences Discuss., https://doi.org/10.5194/bg-2019-502, https://doi.org/10.5194/bg-2019-502, 2020
Preprint withdrawn
Ying Zhou, Lubna Dada, Yiliang Liu, Yueyun Fu, Juha Kangasluoma, Tommy Chan, Chao Yan, Biwu Chu, Kaspar R. Daellenbach, Federico Bianchi, Tom V. Kokkonen, Yongchun Liu, Joni Kujansuu, Veli-Matti Kerminen, Tuukka Petäjä, Lin Wang, Jingkun Jiang, and Markku Kulmala
Atmos. Chem. Phys., 20, 1201–1216, https://doi.org/10.5194/acp-20-1201-2020, https://doi.org/10.5194/acp-20-1201-2020, 2020
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In this study, we focus on explaining the concentration variations in the observed particle modes, by relating them to the potential aerosol sources and sinks, and on understanding the connections between these modes. Interestingly, even in the atmospheric cocktail in urban Beijing, secondary new particle formation (NPF) drives the particle number concentration, especially in the sub-3 nm range. We found that the total number concentration is ~ 4 times higher on NPF days than on haze days.
Marja Hemmilä, Ulla Makkonen, Aki Virkkula, Georgia Panagiotopoulou, Juho Aalto, Markku Kulmala, Tuukka Petäjä, Hannele Hakola, and Heidi Hellén
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2019-1157, https://doi.org/10.5194/acp-2019-1157, 2020
Publication in ACP not foreseen
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Amines are atmospheric bases, which can affect to nucleation of aerosols. Lately, a computational study showed that guanidine could be even more effective to stabilize sulphuric acid clusters. In this paper we used a a dynamic flow-through chamber with an online ion chromatograph MARGA coupled with a mass spectrometer (MARGA-MS). We studied amine and guanidine emission from a boreal forest floor in Finland, and find out, that the boreal forest floor is a source of amines and guanidine.
Matti Räsänen, Mika Aurela, Ville Vakkari, Johan P. Beukes, Juha-Pekka Tuovinen, Pieter G. Van Zyl, Miroslav Josipovic, Stefan J. Siebert, Tuomas Laurila, Markku Kulmala, Lauri Laakso, Janne Rinne, Ram Oren, and Gabriel Katul
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2019-651, https://doi.org/10.5194/hess-2019-651, 2020
Revised manuscript not accepted
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The annual ET is approximately equal to precipitation during six measured years for grazed savanna grassland. The computed annual transpiration was highly constrained when rainfall was near or above the long-term mean but was reduced during severe drought year. The developed methodologies can be used in a wide range of arid and semi-arid ecosystems.
Yonghong Wang, Miao Yu, Yuesi Wang, Guiqian Tang, Tao Song, Putian Zhou, Zirui Liu, Bo Hu, Dongsheng Ji, Lili Wang, Xiaowan Zhu, Chao Yan, Mikael Ehn, Wenkang Gao, Yuepeng Pan, Jinyuan Xin, Yang Sun, Veli-Matti Kerminen, Markku Kulmala, and Tuukka Petäjä
Atmos. Chem. Phys., 20, 45–53, https://doi.org/10.5194/acp-20-45-2020, https://doi.org/10.5194/acp-20-45-2020, 2020
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We found a positive particle matter-mixing layer height feedback at three observation platforms at the 325 m Beijing meteorology tower, which is characterized by a shallower mixing layer height and a higher particle matter concentration. Measurements of solar radiation, aerosol chemical composition, meteorology parameters, trace gases and turbulent kinetic energy (TKE) could explain the feedback mechanism to some extent.
Yicheng Shen, Aki Virkkula, Aijun Ding, Krista Luoma, Helmi Keskinen, Pasi P. Aalto, Xuguang Chi, Ximeng Qi, Wei Nie, Xin Huang, Tuukka Petäjä, Markku Kulmala, and Veli-Matti Kerminen
Atmos. Chem. Phys., 19, 15483–15502, https://doi.org/10.5194/acp-19-15483-2019, https://doi.org/10.5194/acp-19-15483-2019, 2019
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Long-term cloud condensation nuclei (CCN) number concentration (NCCN) data are scarce; there are a lot more data on aerosol optical properties (AOPs). It is therefore valuable to derive parameterizations for estimating NCCN from AOP measurements. With the new parameterization NCCN can be estimated from backscatter fraction, scattering Ångström exponent, and total light-scattering coefficient. The NCCN–AOP relationships depend on the geometric mean diameter and the width of the size distribution.
Arnaud P. Praplan, Toni Tykkä, Dean Chen, Michael Boy, Ditte Taipale, Ville Vakkari, Putian Zhou, Tuukka Petäjä, and Heidi Hellén
Atmos. Chem. Phys., 19, 14431–14453, https://doi.org/10.5194/acp-19-14431-2019, https://doi.org/10.5194/acp-19-14431-2019, 2019
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Our study shows that, despite our best efforts and recent progress, our knowledge of the chemical composition of the air under the canopy of a boreal forest still cannot be fully characterized. The discrepancy between the measured total reactivity of the air and the reactivity derived from the known chemical composition highlights the need to better understand the emissions from vegetation, but also other sources, such as the forest soil.
Jingda Liu, Lili Wang, Mingge Li, Zhiheng Liao, Yang Sun, Tao Song, Wenkang Gao, Yonghong Wang, Yan Li, Dongsheng Ji, Bo Hu, Veli-Matti Kerminen, Yuesi Wang, and Markku Kulmala
Atmos. Chem. Phys., 19, 14477–14492, https://doi.org/10.5194/acp-19-14477-2019, https://doi.org/10.5194/acp-19-14477-2019, 2019
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We analyzed the surface ozone variation characteristics and quantified the impact of synoptic and local meteorological factors on northern China during the warm season based on multi-city, in situ ozone and meteorological data, as well as meteorological reanalysis. The results of quantitative exploration on synoptic and local meteorological factors influencing both interannual and day-to-day ozone variations will provide the scientific basis for evaluating emission reduction measures.
Simonas Kecorius, Teresa Vogl, Pauli Paasonen, Janne Lampilahti, Daniel Rothenberg, Heike Wex, Sebastian Zeppenfeld, Manuela van Pinxteren, Markus Hartmann, Silvia Henning, Xianda Gong, Andre Welti, Markku Kulmala, Frank Stratmann, Hartmut Herrmann, and Alfred Wiedensohler
Atmos. Chem. Phys., 19, 14339–14364, https://doi.org/10.5194/acp-19-14339-2019, https://doi.org/10.5194/acp-19-14339-2019, 2019
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Arctic sea-ice retreat, atmospheric new particle formation (NPF), and aerosol–cloud interaction may all be linked via a positive feedback mechanism. Understanding the sources of cloud condensation nuclei (CCN) is an important piece in the Arctic amplification puzzle. We show that Arctic newly formed particles do not have to grow beyond the Aitken mode to act as CCN. This is important, because NPF occurrence in the Arctic is expected to increase, making it a significant contributor to CCN budget.
Justine Ngoma, Maarten C. Braakhekke, Bart Kruijt, Eddy Moors, Iwan Supit, James H. Speer, Royd Vinya, and Rik Leemans
Biogeosciences, 16, 3853–3867, https://doi.org/10.5194/bg-16-3853-2019, https://doi.org/10.5194/bg-16-3853-2019, 2019
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The Zambezi teak forests are a source of raw material for the timber industry. Through application of the LPJ-GUESS vegetation model, we determined the forests' response to climate change at the wetter Kabompo, drier Sesheke, and intermediate Namwala sites in Zambia. While increased CO2 concentration enhances forests' productivity at Kabompo and Namwala, the decreased rainfall will reduce forests' productivity at Sesheke by the year 2099, resulting in reduced raw material for saw millers.
Paul C. Stoy, Tarek S. El-Madany, Joshua B. Fisher, Pierre Gentine, Tobias Gerken, Stephen P. Good, Anne Klosterhalfen, Shuguang Liu, Diego G. Miralles, Oscar Perez-Priego, Angela J. Rigden, Todd H. Skaggs, Georg Wohlfahrt, Ray G. Anderson, A. Miriam J. Coenders-Gerrits, Martin Jung, Wouter H. Maes, Ivan Mammarella, Matthias Mauder, Mirco Migliavacca, Jacob A. Nelson, Rafael Poyatos, Markus Reichstein, Russell L. Scott, and Sebastian Wolf
Biogeosciences, 16, 3747–3775, https://doi.org/10.5194/bg-16-3747-2019, https://doi.org/10.5194/bg-16-3747-2019, 2019
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Key findings are the nearly optimal response of T to atmospheric water vapor pressure deficits across methods and scales. Additionally, the notion that T / ET intermittently approaches 1, which is a basis for many partitioning methods, does not hold for certain methods and ecosystems. To better constrain estimates of E and T from combined ET measurements, we propose a combination of independent measurement techniques to better constrain E and T at the ecosystem scale.
Jarmo Mäkelä, Jürgen Knauer, Mika Aurela, Andrew Black, Martin Heimann, Hideki Kobayashi, Annalea Lohila, Ivan Mammarella, Hank Margolis, Tiina Markkanen, Jouni Susiluoto, Tea Thum, Toni Viskari, Sönke Zaehle, and Tuula Aalto
Geosci. Model Dev., 12, 4075–4098, https://doi.org/10.5194/gmd-12-4075-2019, https://doi.org/10.5194/gmd-12-4075-2019, 2019
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We assess the differences of six stomatal conductance formulations, embedded into a land–vegetation model JSBACH, on 10 boreal coniferous evergreen forest sites. We calibrate the model parameters using all six functions in a multi-year experiment, as well as for a separate drought event at one of the sites, using the adaptive population importance sampler. The analysis reveals weaknesses in the stomatal conductance formulation-dependent model behaviour that we are able to partially amend.
Krista Luoma, Aki Virkkula, Pasi Aalto, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 19, 11363–11382, https://doi.org/10.5194/acp-19-11363-2019, https://doi.org/10.5194/acp-19-11363-2019, 2019
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We present an over 10-year-long time series of aerosol optical properties (AOPs) measured at a rural boreal forest site. Knowledge of AOPs is needed in determining the direct effect of aerosol particles on climate. We observed decreasing trends in scattering and absorption and increasing trends in backscattering fraction and single-scattering albedo. Trends of single-scattering albedo and backscattering fraction increased the efficiency of aerosol particles to scatter radiation back into space.
Petri Kiuru, Anne Ojala, Ivan Mammarella, Jouni Heiskanen, Kukka-Maaria Erkkilä, Heli Miettinen, Timo Vesala, and Timo Huttula
Biogeosciences, 16, 3297–3317, https://doi.org/10.5194/bg-16-3297-2019, https://doi.org/10.5194/bg-16-3297-2019, 2019
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Many boreal lakes emit the greenhouse gas carbon dioxide (CO2) to the atmosphere. We incorporated four different gas exchange models into a physico-biochemical lake model and studied their ability to simulate lake air–water CO2 fluxes. The inclusion of refined gas exchange models in lake models that simulate carbon cycling is important to assess lake carbon budgets. However, higher estimates for inorganic carbon sources in boreal lakes are needed to balance the CO2 losses to the atmosphere.
Olli Peltola, Timo Vesala, Yao Gao, Olle Räty, Pavel Alekseychik, Mika Aurela, Bogdan Chojnicki, Ankur R. Desai, Albertus J. Dolman, Eugenie S. Euskirchen, Thomas Friborg, Mathias Göckede, Manuel Helbig, Elyn Humphreys, Robert B. Jackson, Georg Jocher, Fortunat Joos, Janina Klatt, Sara H. Knox, Natalia Kowalska, Lars Kutzbach, Sebastian Lienert, Annalea Lohila, Ivan Mammarella, Daniel F. Nadeau, Mats B. Nilsson, Walter C. Oechel, Matthias Peichl, Thomas Pypker, William Quinton, Janne Rinne, Torsten Sachs, Mateusz Samson, Hans Peter Schmid, Oliver Sonnentag, Christian Wille, Donatella Zona, and Tuula Aalto
Earth Syst. Sci. Data, 11, 1263–1289, https://doi.org/10.5194/essd-11-1263-2019, https://doi.org/10.5194/essd-11-1263-2019, 2019
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Here we develop a monthly gridded dataset of northern (> 45 N) wetland methane (CH4) emissions. The data product is derived using a random forest machine-learning technique and eddy covariance CH4 fluxes from 25 wetland sites. Annual CH4 emissions from these wetlands calculated from the derived data product are comparable to prior studies focusing on these areas. This product is an independent estimate of northern wetland CH4 emissions and hence could be used, e.g. for process model evaluation.
Simo Hakala, Mansour A. Alghamdi, Pauli Paasonen, Ville Vakkari, Mamdouh I. Khoder, Kimmo Neitola, Lubna Dada, Ahmad S. Abdelmaksoud, Hisham Al-Jeelani, Ibrahim I. Shabbaj, Fahd M. Almehmadi, Anu-Maija Sundström, Heikki Lihavainen, Veli-Matti Kerminen, Jenni Kontkanen, Markku Kulmala, Tareq Hussein, and Antti-Pekka Hyvärinen
Atmos. Chem. Phys., 19, 10537–10555, https://doi.org/10.5194/acp-19-10537-2019, https://doi.org/10.5194/acp-19-10537-2019, 2019
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Atmospheric aerosols have significant effects on human health and the climate. A large fraction of these aerosols originate from new particle formation, where atmospheric vapors form small nanosized particles that grow into larger sizes, thus becoming climatically relevant. We show that large amounts of fast-growing particles are formed frequently at a site located in western Saudi Arabia and that these particles are likely connected to strong nearby emissions from human activities.
Elisa Männistö, Aino Korrensalo, Pavel Alekseychik, Ivan Mammarella, Olli Peltola, Timo Vesala, and Eeva-Stiina Tuittila
Biogeosciences, 16, 2409–2421, https://doi.org/10.5194/bg-16-2409-2019, https://doi.org/10.5194/bg-16-2409-2019, 2019
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We studied methane emitted as episodic bubble release (ebullition) from water and bare peat surfaces of a boreal bog over three years. There was more ebullition from water than from bare peat surfaces, and it was controlled by peat temperature, water level, atmospheric pressure and the weekly temperature sum. However, the contribution of methane bubbles to the total ecosystem methane emission was small. This new information can be used to improve process models of peatland methane dynamics.
Kaspar R. Daellenbach, Ivan Kourtchev, Alexander L. Vogel, Emily A. Bruns, Jianhui Jiang, Tuukka Petäjä, Jean-Luc Jaffrezo, Sebnem Aksoyoglu, Markus Kalberer, Urs Baltensperger, Imad El Haddad, and André S. H. Prévôt
Atmos. Chem. Phys., 19, 5973–5991, https://doi.org/10.5194/acp-19-5973-2019, https://doi.org/10.5194/acp-19-5973-2019, 2019
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Here we present the molecular composition of the organic aerosol (OA) at an urban site in Central Europe (Zurich, Switzerland) and compare it to smog chamber wood smoke and ambient biogenic secondary OA (SOA) (Orbitrap analyses). Accordingly, we are able to explain the strong seasonality of the molecular composition by aged wood smoke and biogenic SOA during winter and summer. Our results could also explain the predominance of non-fossil organic carbon at European locations throughout the year.
Yonghong Wang, Yuesi Wang, Lili Wang, Tuukka Petäjä, Qiaozhi Zha, Chongshui Gong, Sixuan Li, Yuepeng Pan, Bo Hu, Jinyuan Xin, and Markku Kulmala
Atmos. Chem. Phys., 19, 5881–5888, https://doi.org/10.5194/acp-19-5881-2019, https://doi.org/10.5194/acp-19-5881-2019, 2019
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Satellite observations combined with in situ measurements demonstrate that increased inorganic aerosol fractions of NO2 and SO2 contribute to air pollution and frequently occurring haze in China from 1980 to 2010. Currently, the reduction of nitrate, sulfate and their precursor gases would contribute towards better visibility in China.
Matthieu Riva, Pekka Rantala, Jordan E. Krechmer, Otso Peräkylä, Yanjun Zhang, Liine Heikkinen, Olga Garmash, Chao Yan, Markku Kulmala, Douglas Worsnop, and Mikael Ehn
Atmos. Meas. Tech., 12, 2403–2421, https://doi.org/10.5194/amt-12-2403-2019, https://doi.org/10.5194/amt-12-2403-2019, 2019
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The impact of aerosol particles on climate and air quality remains poorly understood due to multiple factors. One of the current limitations is the incomplete understanding of the contribution of oxygenated species, formed from the oxidation of volatile organic compounds (VOCs) to aerosol formation. Taking advantage of recent mass spectrometric developments, we have evaluated and compared the capability of multiple state-of-the-art mass spectrometers to detect a wide variety of oxygenated VOCs.
Katri Leino, Janne Lampilahti, Pyry Poutanen, Riikka Väänänen, Antti Manninen, Stephany Buenrostro Mazon, Lubna Dada, Anna Franck, Daniela Wimmer, Pasi P. Aalto, Lauri R. Ahonen, Joonas Enroth, Juha Kangasluoma, Petri Keronen, Frans Korhonen, Heikki Laakso, Teemu Matilainen, Erkki Siivola, Hanna E. Manninen, Katrianne Lehtipalo, Veli-Matti Kerminen, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 19, 4127–4138, https://doi.org/10.5194/acp-19-4127-2019, https://doi.org/10.5194/acp-19-4127-2019, 2019
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This study presents airborne observations of particles, starting from 1.5 nm in diameter, above the boreal forest from 100 m up to 2700 m. The aim was to study the extent of NPF and likely places for nucleation. We found that the highest concentrations of 1.5–3 nm particles were above the forest canopy top on NPF event mornings, and the concentration decreased with increasing altitude. This would indicate the importance of gaseous precursors from vegetation for NPF processes in this area.
Mikko Äijälä, Kaspar R. Daellenbach, Francesco Canonaco, Liine Heikkinen, Heikki Junninen, Tuukka Petäjä, Markku Kulmala, André S. H. Prévôt, and Mikael Ehn
Atmos. Chem. Phys., 19, 3645–3672, https://doi.org/10.5194/acp-19-3645-2019, https://doi.org/10.5194/acp-19-3645-2019, 2019
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Aerosol mass spectrometry produces large amounts of complex data, the analysis of which necessitates chemometrics – the application of advanced statistical and mathematical tools to chemical data. Here, we perform a data-driven analysis of multiple aerosol mass spectrometric data sets, to show that the traditional separation of organics and inorganics is not necessary. The resulting 7-component aerosol speciation explains 83 % to 96 % of observed variability at our boreal forest experiment site.
Nikos Kalivitis, Veli-Matti Kerminen, Giorgos Kouvarakis, Iasonas Stavroulas, Evaggelia Tzitzikalaki, Panayiotis Kalkavouras, Nikos Daskalakis, Stelios Myriokefalitakis, Aikaterini Bougiatioti, Hanna E. Manninen, Pontus Roldin, Tuukka Petäjä, Michael Boy, Markku Kulmala, Maria Kanakidou, and Nikolaos Mihalopoulos
Atmos. Chem. Phys., 19, 2671–2686, https://doi.org/10.5194/acp-19-2671-2019, https://doi.org/10.5194/acp-19-2671-2019, 2019
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New particle formation (NPF) is an important source of atmospheric aerosols. For the Mediterranean atmosphere, only few studies exist. In this study we present one of the longest series of NPF by analyzing 10 years of data from Crete, Greece. NPF took place on 27 % of the available days; it was more frequent in spring and less so in late summer. Model simulations showed that NPF in the subtropical environment may differ greatly from that in the boreal environment.
Michael Boy, Erik S. Thomson, Juan-C. Acosta Navarro, Olafur Arnalds, Ekaterina Batchvarova, Jaana Bäck, Frank Berninger, Merete Bilde, Zoé Brasseur, Pavla Dagsson-Waldhauserova, Dimitri Castarède, Maryam Dalirian, Gerrit de Leeuw, Monika Dragosics, Ella-Maria Duplissy, Jonathan Duplissy, Annica M. L. Ekman, Keyan Fang, Jean-Charles Gallet, Marianne Glasius, Sven-Erik Gryning, Henrik Grythe, Hans-Christen Hansson, Margareta Hansson, Elisabeth Isaksson, Trond Iversen, Ingibjorg Jonsdottir, Ville Kasurinen, Alf Kirkevåg, Atte Korhola, Radovan Krejci, Jon Egill Kristjansson, Hanna K. Lappalainen, Antti Lauri, Matti Leppäranta, Heikki Lihavainen, Risto Makkonen, Andreas Massling, Outi Meinander, E. Douglas Nilsson, Haraldur Olafsson, Jan B. C. Pettersson, Nønne L. Prisle, Ilona Riipinen, Pontus Roldin, Meri Ruppel, Matthew Salter, Maria Sand, Øyvind Seland, Heikki Seppä, Henrik Skov, Joana Soares, Andreas Stohl, Johan Ström, Jonas Svensson, Erik Swietlicki, Ksenia Tabakova, Throstur Thorsteinsson, Aki Virkkula, Gesa A. Weyhenmeyer, Yusheng Wu, Paul Zieger, and Markku Kulmala
Atmos. Chem. Phys., 19, 2015–2061, https://doi.org/10.5194/acp-19-2015-2019, https://doi.org/10.5194/acp-19-2015-2019, 2019
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The Nordic Centre of Excellence CRAICC (Cryosphere–Atmosphere Interactions in a Changing Arctic Climate), funded by NordForsk in the years 2011–2016, is the largest joint Nordic research and innovation initiative to date and aimed to strengthen research and innovation regarding climate change issues in the Nordic region. The paper presents an overview of the main scientific topics investigated and provides a state-of-the-art comprehensive summary of what has been achieved in CRAICC.
Timo Vihma, Petteri Uotila, Stein Sandven, Dmitry Pozdnyakov, Alexander Makshtas, Alexander Pelyasov, Roberta Pirazzini, Finn Danielsen, Sergey Chalov, Hanna K. Lappalainen, Vladimir Ivanov, Ivan Frolov, Anna Albin, Bin Cheng, Sergey Dobrolyubov, Viktor Arkhipkin, Stanislav Myslenkov, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 19, 1941–1970, https://doi.org/10.5194/acp-19-1941-2019, https://doi.org/10.5194/acp-19-1941-2019, 2019
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The Arctic marine climate system, ecosystems, and socio-economic systems are changing rapidly. This calls for the establishment of a marine Arctic component of the Pan-Eurasian Experiment (MA-PEEX), for which we present a plan. The program will promote international collaboration; sustainable marine meteorological, sea ice, and oceanographic observations; advanced data management; and multidisciplinary research on the marine Arctic and its interaction with the Eurasian continent.
Yiqun Lu, Chao Yan, Yueyun Fu, Yan Chen, Yiliang Liu, Gan Yang, Yuwei Wang, Federico Bianchi, Biwu Chu, Ying Zhou, Rujing Yin, Rima Baalbaki, Olga Garmash, Chenjuan Deng, Weigang Wang, Yongchun Liu, Tuukka Petäjä, Veli-Matti Kerminen, Jingkun Jiang, Markku Kulmala, and Lin Wang
Atmos. Chem. Phys., 19, 1971–1983, https://doi.org/10.5194/acp-19-1971-2019, https://doi.org/10.5194/acp-19-1971-2019, 2019
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Gaseous sulfuric acid is one of the key precursors for atmospheric new particle formation processes, but its measurement remains challenging. This work develops an estimation method for the gaseous sulfuric acid concentration in an urban environment in China using multiple atmospheric variables that are easier to measure. The consideration of the heterogeneous formation of HONO and the subsequent photo-production of OH radicals improves the performance of the estimation method.
Biwu Chu, Veli-Matti Kerminen, Federico Bianchi, Chao Yan, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 19, 115–138, https://doi.org/10.5194/acp-19-115-2019, https://doi.org/10.5194/acp-19-115-2019, 2019
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The characteristics of new particle formation (NPF) in China, including frequency, formation rate, and particle growth rate, were summarized comprehensively and were compared among observations in different environments. The interactions between air pollution and NPF are discussed, as well as the possible reasons for more frequent NPF under heavy pollution conditions than in our current understanding. Significant and future research directions for NPF studies in China are also summarized.
Anja Rammig, Jens Heinke, Florian Hofhansl, Hans Verbeeck, Timothy R. Baker, Bradley Christoffersen, Philippe Ciais, Hannes De Deurwaerder, Katrin Fleischer, David Galbraith, Matthieu Guimberteau, Andreas Huth, Michelle Johnson, Bart Krujit, Fanny Langerwisch, Patrick Meir, Phillip Papastefanou, Gilvan Sampaio, Kirsten Thonicke, Celso von Randow, Christian Zang, and Edna Rödig
Geosci. Model Dev., 11, 5203–5215, https://doi.org/10.5194/gmd-11-5203-2018, https://doi.org/10.5194/gmd-11-5203-2018, 2018
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We propose a generic approach for a pixel-to-point comparison applicable for evaluation of models and remote-sensing products. We provide statistical measures accounting for the uncertainty in ecosystem variables. We demonstrate our approach by comparing simulated values of aboveground biomass, woody productivity and residence time of woody biomass from four dynamic global vegetation models (DGVMs) with measured inventory data from permanent plots in the Amazon rainforest.
Fidel Pankratov, Alexander Mahura, Tuukka Petäjä, Valentin Popov, and Vladimir Masloboev
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2018-1228, https://doi.org/10.5194/acp-2018-1228, 2018
Revised manuscript not accepted
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Analysis of long-term observations for atmospheric mercury in the Russian Arctic, considering inter-annual, seasonal and monthly variabilities is in focus. Linkage of elevated concentrations with volcanic eruptions in Iceland is explored. Results showed that active volcanoes can play a role of sources for increased mercury levels in the Northern Hemisphere due to long-range atmospheric transport of volcanic clouds towards the Arctic.
Lubna Dada, Robert Chellapermal, Stephany Buenrostro Mazon, Pauli Paasonen, Janne Lampilahti, Hanna E. Manninen, Heikki Junninen, Tuukka Petäjä, Veli-Matti Kerminen, and Markku Kulmala
Atmos. Chem. Phys., 18, 17883–17893, https://doi.org/10.5194/acp-18-17883-2018, https://doi.org/10.5194/acp-18-17883-2018, 2018
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Our paper provides an automatic method to classify new particle formation events into four classes based on the accompanying air ion concentrations. The method is applied to 10 years of data measured within the SMEAR II station and was capable of eliminating the undefined class as well as defining the start, peak and end times of a regional event by monitoring the initial steps of cluster formation. Our method can be modified and applied to different locations where particle formation occurs.
Ekaterina Ezhova, Ilona Ylivinkka, Joel Kuusk, Kaupo Komsaare, Marko Vana, Alisa Krasnova, Steffen Noe, Mikhail Arshinov, Boris Belan, Sung-Bin Park, Jošt Valentin Lavrič, Martin Heimann, Tuukka Petäjä, Timo Vesala, Ivan Mammarella, Pasi Kolari, Jaana Bäck, Üllar Rannik, Veli-Matti Kerminen, and Markku Kulmala
Atmos. Chem. Phys., 18, 17863–17881, https://doi.org/10.5194/acp-18-17863-2018, https://doi.org/10.5194/acp-18-17863-2018, 2018
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Understanding the connections between aerosols, solar radiation and photosynthesis in terrestrial ecosystems is important for estimates of the CO2 balance in the atmosphere. Atmospheric aerosols and clouds influence solar radiation. In this study, we quantify the aerosol effect on solar radiation in boreal forests and study forest ecosystems response to this change in the radiation conditions. The analysis is based on atmospheric observations from several remote stations in Eurasian forests.
Liqing Hao, Olga Garmash, Mikael Ehn, Pasi Miettinen, Paola Massoli, Santtu Mikkonen, Tuija Jokinen, Pontus Roldin, Pasi Aalto, Taina Yli-Juuti, Jorma Joutsensaari, Tuukka Petäjä, Markku Kulmala, Kari E. J. Lehtinen, Douglas R. Worsnop, and Annele Virtanen
Atmos. Chem. Phys., 18, 17705–17716, https://doi.org/10.5194/acp-18-17705-2018, https://doi.org/10.5194/acp-18-17705-2018, 2018
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An aerosol mass spectrometer was used to characterize aerosol chemical composition during new particle formation periods. The time profiles of mass concentrations and chemical composition of observed aerosol particles are subjected to joint effects of boundary layer dilution, atmospheric chemistry and aerosol mixing in different boundary layers. During the nighttime, the increase in organic aerosol mass correlated well with the increase in condensed highly oxygenated organic molecules' mass.
Qiaozhi Zha, Chao Yan, Heikki Junninen, Matthieu Riva, Nina Sarnela, Juho Aalto, Lauriane Quéléver, Simon Schallhart, Lubna Dada, Liine Heikkinen, Otso Peräkylä, Jun Zou, Clémence Rose, Yonghong Wang, Ivan Mammarella, Gabriel Katul, Timo Vesala, Douglas R. Worsnop, Markku Kulmala, Tuukka Petäjä, Federico Bianchi, and Mikael Ehn
Atmos. Chem. Phys., 18, 17437–17450, https://doi.org/10.5194/acp-18-17437-2018, https://doi.org/10.5194/acp-18-17437-2018, 2018
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Vertical measurements of highly oxygenated molecules (HOMs) below and above the forest canopy were performed for the first time in a boreal forest during September 2016. Our results highlight that near-ground HOM measurements may only be representative of a small fraction of the entire nocturnal boundary layer, which may sequentially influence the growth of newly formed particles and SOA formation close to ground surface, where the majority of measurements are conducted.
Cristina Carnerero, Noemí Pérez, Cristina Reche, Marina Ealo, Gloria Titos, Hong-Ku Lee, Hee-Ram Eun, Yong-Hee Park, Lubna Dada, Pauli Paasonen, Veli-Matti Kerminen, Enrique Mantilla, Miguel Escudero, Francisco J. Gómez-Moreno, Elisabeth Alonso-Blanco, Esther Coz, Alfonso Saiz-Lopez, Brice Temime-Roussel, Nicolas Marchand, David C. S. Beddows, Roy M. Harrison, Tuukka Petäjä, Markku Kulmala, Kang-Ho Ahn, Andrés Alastuey, and Xavier Querol
Atmos. Chem. Phys., 18, 16601–16618, https://doi.org/10.5194/acp-18-16601-2018, https://doi.org/10.5194/acp-18-16601-2018, 2018
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The vertical distribution of new particle formation events was studied using tethered balloons carrying miniaturized instrumentation. Results show that new particle formation and growth occurs only in the lower layer of the atmosphere, where aerosols are mixed due to convection, especially when the atmosphere is clean. A comparison of urban and suburban surface stations was also made, suggesting that such events may have a significant impact on ultrafine particle concentrations in a wide area.
Tracey Leah Laban, Pieter Gideon van Zyl, Johan Paul Beukes, Ville Vakkari, Kerneels Jaars, Nadine Borduas-Dedekind, Miroslav Josipovic, Anne Mee Thompson, Markku Kulmala, and Lauri Laakso
Atmos. Chem. Phys., 18, 15491–15514, https://doi.org/10.5194/acp-18-15491-2018, https://doi.org/10.5194/acp-18-15491-2018, 2018
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Surface O3 was measured at four sites in the north-eastern interior of South Africa, which revealed that O3 is a regional problem in continental South Africa, with elevated O3 levels found at rural background and industrial sites. Increased O3 concentrations were associated with high CO levels predominantly related to regional biomass burning, while the O3 production regime was established to be predominantly VOC limited. Increased O3 is associated with strong seasonality of precursor sources.
Tuomo Nieminen, Veli-Matti Kerminen, Tuukka Petäjä, Pasi P. Aalto, Mikhail Arshinov, Eija Asmi, Urs Baltensperger, David C. S. Beddows, Johan Paul Beukes, Don Collins, Aijun Ding, Roy M. Harrison, Bas Henzing, Rakesh Hooda, Min Hu, Urmas Hõrrak, Niku Kivekäs, Kaupo Komsaare, Radovan Krejci, Adam Kristensson, Lauri Laakso, Ari Laaksonen, W. Richard Leaitch, Heikki Lihavainen, Nikolaos Mihalopoulos, Zoltán Németh, Wei Nie, Colin O'Dowd, Imre Salma, Karine Sellegri, Birgitta Svenningsson, Erik Swietlicki, Peter Tunved, Vidmantas Ulevicius, Ville Vakkari, Marko Vana, Alfred Wiedensohler, Zhijun Wu, Annele Virtanen, and Markku Kulmala
Atmos. Chem. Phys., 18, 14737–14756, https://doi.org/10.5194/acp-18-14737-2018, https://doi.org/10.5194/acp-18-14737-2018, 2018
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Atmospheric aerosols have diverse effects on air quality, human health, and global climate. One important source of aerosols is their formation via nucleation and growth in the atmosphere. We have analyzed long-term observations of regional new particle formation events around the globe and provide a comprehensive view on the characteristics of this phenomenon in diverse environments. The results are useful in developing more realistic representation of atmospheric aerosols in global models.
Juan Hong, Hanbing Xu, Haobo Tan, Changqing Yin, Liqing Hao, Fei Li, Mingfu Cai, Xuejiao Deng, Nan Wang, Hang Su, Yafang Cheng, Lin Wang, Tuukka Petäjä, and Veli-Matti Kerminen
Atmos. Chem. Phys., 18, 14079–14094, https://doi.org/10.5194/acp-18-14079-2018, https://doi.org/10.5194/acp-18-14079-2018, 2018
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In this manuscript, we provide the results of the hygroscopicity of a more anthropogenically influenced aerosol in a suburban site in China. Organic material in the current type of aerosols showed moderate hygroscopicity, and it appeared to be less sensitive towards the variation of its oxidation level, which suggests different characteristics of the oxidation products in secondary organic aerosols (SOA) under the suburban/urban atmosphere in China when compared to other background environments.
Heidi Hellén, Arnaud P. Praplan, Toni Tykkä, Ilona Ylivinkka, Ville Vakkari, Jaana Bäck, Tuukka Petäjä, Markku Kulmala, and Hannele Hakola
Atmos. Chem. Phys., 18, 13839–13863, https://doi.org/10.5194/acp-18-13839-2018, https://doi.org/10.5194/acp-18-13839-2018, 2018
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Exceptionally large ambient air concentration datasets of VOCs were measured in a boreal forest. For the first time concentration of the main sesquiterpene (β-caryophyllene) emitted by the local trees was also measured. Sesquiterpenes were found to have a major impact on local atmospheric chemistry, even though their concentrations were 30 times lower than the monoterpene concentrations. In addition, sesquiterpenes are expected to have a high impact on local secondary organic aerosol production.
David Patoulias, Christos Fountoukis, Ilona Riipinen, Ari Asmi, Markku Kulmala, and Spyros N. Pandis
Atmos. Chem. Phys., 18, 13639–13654, https://doi.org/10.5194/acp-18-13639-2018, https://doi.org/10.5194/acp-18-13639-2018, 2018
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PMCAMx-UF, a 3-D chemical transport model focusing on the simulation of ultrafine particles, has been extended with the addition of the volatility basis set (VBS) approach for the simulation of organic aerosol. The model was applied in Europe and its predictions were evaluated against field observations collected during the PEGASOS 2012 campaign. The condensation of organics led to an increase (50–120 %) in the larger particles but the total number concentration decreased by 10–30 %.
Jenni Kontkanen, Tinja Olenius, Markku Kulmala, and Ilona Riipinen
Atmos. Chem. Phys., 18, 13733–13754, https://doi.org/10.5194/acp-18-13733-2018, https://doi.org/10.5194/acp-18-13733-2018, 2018
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New particle formation involving sulfuric acid, bases and organic compounds is an important source of atmospheric aerosol particles. We investigate the capability of nano-Köhler theory to describe this process by simulating the dynamics of atmospheric molecular clusters. We find that nano-Köhler-type behavior occurs in our simulations when the saturation ratio of the organic vapor and the ratio between organic and inorganic vapor concentrations are in a suitable range.
John N. Crowley, Nicolas Pouvesle, Gavin J. Phillips, Raoul Axinte, Horst Fischer, Tuukka Petäjä, Anke Nölscher, Jonathan Williams, Korbinian Hens, Hartwig Harder, Monica Martinez-Harder, Anna Novelli, Dagmar Kubistin, Birger Bohn, and Jos Lelieveld
Atmos. Chem. Phys., 18, 13457–13479, https://doi.org/10.5194/acp-18-13457-2018, https://doi.org/10.5194/acp-18-13457-2018, 2018
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Simultaneous observations of PAA, PAN and H2O2 are used to provide insight into processes influencing the HOx chemistry of the boreal forest, including two biomass-burning-impacted periods. A significant contribution from photolytic HOx sources was included in a box model analysis to align model predictions with measurements. The model predicts high levels of organic peroxy radicals, also at night-time.
Daniela Wimmer, Stephany Buenrostro Mazon, Hanna Elina Manninen, Juha Kangasluoma, Alessandro Franchin, Tuomo Nieminen, John Backman, Jian Wang, Chongai Kuang, Radovan Krejci, Joel Brito, Fernando Goncalves Morais, Scot Turnbull Martin, Paulo Artaxo, Markku Kulmala, Veli-Matti Kerminen, and Tuukka Petäjä
Atmos. Chem. Phys., 18, 13245–13264, https://doi.org/10.5194/acp-18-13245-2018, https://doi.org/10.5194/acp-18-13245-2018, 2018
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This work focuses on understanding the production of very small airborne particles in the undisturbed environment of the Amazon basin. Computer models have shown that up to 70 % of these tiny particles are responsible for cloud formation on a global scale. The processes behind the production of these very small particles have been studied intensely recently. Their appearance has been observed almost all over the world. We directly measure sub-3 nm aerosols for the first time in the Amazon basin.
Chao Yan, Lubna Dada, Clémence Rose, Tuija Jokinen, Wei Nie, Siegfried Schobesberger, Heikki Junninen, Katrianne Lehtipalo, Nina Sarnela, Ulla Makkonen, Olga Garmash, Yonghong Wang, Qiaozhi Zha, Pauli Paasonen, Federico Bianchi, Mikko Sipilä, Mikael Ehn, Tuukka Petäjä, Veli-Matti Kerminen, Douglas R. Worsnop, and Markku Kulmala
Atmos. Chem. Phys., 18, 13231–13243, https://doi.org/10.5194/acp-18-13231-2018, https://doi.org/10.5194/acp-18-13231-2018, 2018
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Ions can play an important role in atmospheric new particle formation by stabilizing the embryonic clusters. Such a process is called ion-induced nucleation (IIN). We found two distinct IIN mechanisms – driven by H2SO4-NH3 clusters and by organic vapors, respectively. The concentration ratio of organic vapors to H2SO4 regulates via which pathway the IIN occur. As the organic vapor concentration is influenced by temperature, a seasonal variation in the main IIN mechanism can be expected.
Jason A. Ducker, Christopher D. Holmes, Trevor F. Keenan, Silvano Fares, Allen H. Goldstein, Ivan Mammarella, J. William Munger, and Jordan Schnell
Biogeosciences, 15, 5395–5413, https://doi.org/10.5194/bg-15-5395-2018, https://doi.org/10.5194/bg-15-5395-2018, 2018
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We have developed an accurate method (SynFlux) to estimate ozone deposition and stomatal uptake across 103 flux tower sites (43 US, 60 Europe), where ozone concentrations and fluxes have not been measured. In all, the SynFlux public dataset provides monthly values of ozone dry deposition for 926 site years across a wide array of ecosystems. The SynFlux dataset will promote further applications to ecosystem, air quality, or climate modeling across the geoscience community.
Martha A. Zaidan, Ville Haapasilta, Rishi Relan, Pauli Paasonen, Veli-Matti Kerminen, Heikki Junninen, Markku Kulmala, and Adam S. Foster
Atmos. Chem. Phys., 18, 12699–12714, https://doi.org/10.5194/acp-18-12699-2018, https://doi.org/10.5194/acp-18-12699-2018, 2018
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This article promotes the use of the mutual information method for finding any non-linear associations among atmospheric variables. We demonstrate that the same results from previous studies are obtained by this method, which operates without supervision and without the need of understanding the physics deeply. This suggests that the method is suitable to be implemented widely in the atmospheric field to discover other interesting phenomena and their relevant variables.
Anni Vanhatalo, Andrea Ghirardo, Eija Juurola, Jörg-Peter Schnitzler, Ina Zimmer, Heidi Hellén, Hannele Hakola, and Jaana Bäck
Biogeosciences, 15, 5047–5060, https://doi.org/10.5194/bg-15-5047-2018, https://doi.org/10.5194/bg-15-5047-2018, 2018
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We analysed the relationships between Scots pine needle monoterpene synthase activities, monoterpene storage pools and emissions of needles. The results showed changes in the monoterpene synthase activity of needles, linked to seasonality and needle ontogenesis, while the pool did not change considerably as a function of needle aging. Monoterpene emissions did not correlate with synthase activity or storage pool size. Additionally, we observed notably high plant-to-plant variation.
Pauli Paasonen, Maija Peltola, Jenni Kontkanen, Heikki Junninen, Veli-Matti Kerminen, and Markku Kulmala
Atmos. Chem. Phys., 18, 12085–12103, https://doi.org/10.5194/acp-18-12085-2018, https://doi.org/10.5194/acp-18-12085-2018, 2018
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We determine aerosol growth rates in diameter ranges from below 10 to over 300 nm from long-term data with a novel automatic method. We show that aerosol growth rate in boreal forest increases with increasing particle diameter from 10 nm to cloud condensation nuclei (CCN) sizes and that the growth rate of sub-CCN particles is not suppressed by increasing condensation sink. Our findings suggest that aerosol growth to CCN sizes is a faster and less self-regulated process than previously estimated.
Ximeng Qi, Aijun Ding, Pontus Roldin, Zhengning Xu, Putian Zhou, Nina Sarnela, Wei Nie, Xin Huang, Anton Rusanen, Mikael Ehn, Matti P. Rissanen, Tuukka Petäjä, Markku Kulmala, and Michael Boy
Atmos. Chem. Phys., 18, 11779–11791, https://doi.org/10.5194/acp-18-11779-2018, https://doi.org/10.5194/acp-18-11779-2018, 2018
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In this study we simulate the HOM concentrations and discuss their roles in NPF at a remote boreal forest site in Finland and a suburban site in eastern China. We found that sulfuric acid and HOM organonitrate concentrations in the gas phase are significantly higher but other HOM monomers and dimers from monoterpene oxidation are lower in eastern China. This study highlights the need for molecular-scale measurements in improving the understanding of NPF mechanisms in polluted areas.
Ben H. Lee, Felipe D. Lopez-Hilfiker, Emma L. D'Ambro, Putian Zhou, Michael Boy, Tuukka Petäjä, Liqing Hao, Annele Virtanen, and Joel A. Thornton
Atmos. Chem. Phys., 18, 11547–11562, https://doi.org/10.5194/acp-18-11547-2018, https://doi.org/10.5194/acp-18-11547-2018, 2018
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Molecular identities and abundances of organic compounds residing in the gas and particle phases above a Finnish boreal forest are presented. We determined that in each phase, the organic components are categorized into three subgroups based on their behavior in time. Some are more enhanced at night, others during midday, and another around sunrise. Identifying such collective behavior can potentially connect the chemical processes that evolve in time to specific distributions of products.
Runlong Cai, Dongsen Yang, Lauri R. Ahonen, Linlin Shi, Frans Korhonen, Yan Ma, Jiming Hao, Tuukka Petäjä, Jun Zheng, Juha Kangasluoma, and Jingkun Jiang
Atmos. Meas. Tech., 11, 4477–4491, https://doi.org/10.5194/amt-11-4477-2018, https://doi.org/10.5194/amt-11-4477-2018, 2018
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We tested the performance of four inversion methods to recover sub-3 nm aerosol size distributions using the particle size magnifier (PSM). The PSM is widely used in new particle formation study; however, the inversion methods used in previous studies may report false particle concentrations. Due to the results, we suggest using the expectation–maximization algorithm to address the PSM inversion problem. We also gave practical suggestions on PSM operation based on the inversion analysis.
Anna Nikandrova, Ksenia Tabakova, Antti Manninen, Riikka Väänänen, Tuukka Petäjä, Markku Kulmala, Veli-Matti Kerminen, and Ewan O'Connor
Atmos. Chem. Phys., 18, 10575–10591, https://doi.org/10.5194/acp-18-10575-2018, https://doi.org/10.5194/acp-18-10575-2018, 2018
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We investigated temporal and vertical aerosol properties in a rural environment during BAECC (Biogenic Aerosols – Effects on Cloud and Climate) campaign. Differences were observed in aerosol number size distribution, variability and mixing in the layers between two case studies: clear-sky and partly cloudy case. We also conclude that care should be taken in selecting appropriate arrival heights of backward trajectories, since the modelled and observed layer heights did not always coincide.
Luciana Varanda Rizzo, Pontus Roldin, Joel Brito, John Backman, Erik Swietlicki, Radovan Krejci, Peter Tunved, Tukka Petäjä, Markku Kulmala, and Paulo Artaxo
Atmos. Chem. Phys., 18, 10255–10274, https://doi.org/10.5194/acp-18-10255-2018, https://doi.org/10.5194/acp-18-10255-2018, 2018
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Aerosols are tiny particles suspended in the air that can interact with sunlight and form clouds, which in turn affect the climate. They can also recycle nutrients in forest environments. Aerosols are naturally emitted at the surface in the Amazon forest, in addition to being brought down from above the boundary layer by intense air movements. In this work, we describe how the particle size number concentrations of aerosols change over hours, days and seasons in a multi-year study in Amazonia.
Filippo Xausa, Pauli Paasonen, Risto Makkonen, Mikhail Arshinov, Aijun Ding, Hugo Denier Van Der Gon, Veli-Matti Kerminen, and Markku Kulmala
Atmos. Chem. Phys., 18, 10039–10054, https://doi.org/10.5194/acp-18-10039-2018, https://doi.org/10.5194/acp-18-10039-2018, 2018
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Our project describes the feasibility of implementing particle number emissions taken from the GAINS model in global climate modeling through a simulation with the ECHAM-HAM global climate model. The results from the simulations have important implications regarding modeled particle number concentrations and future climate effects. Our findings represent an important starting point for further simulations concerning climate effects derived from anthropogenic particle emissions on a global scale.
Mary E. Whelan, Sinikka T. Lennartz, Teresa E. Gimeno, Richard Wehr, Georg Wohlfahrt, Yuting Wang, Linda M. J. Kooijmans, Timothy W. Hilton, Sauveur Belviso, Philippe Peylin, Róisín Commane, Wu Sun, Huilin Chen, Le Kuai, Ivan Mammarella, Kadmiel Maseyk, Max Berkelhammer, King-Fai Li, Dan Yakir, Andrew Zumkehr, Yoko Katayama, Jérôme Ogée, Felix M. Spielmann, Florian Kitz, Bharat Rastogi, Jürgen Kesselmeier, Julia Marshall, Kukka-Maaria Erkkilä, Lisa Wingate, Laura K. Meredith, Wei He, Rüdiger Bunk, Thomas Launois, Timo Vesala, Johan A. Schmidt, Cédric G. Fichot, Ulli Seibt, Scott Saleska, Eric S. Saltzman, Stephen A. Montzka, Joseph A. Berry, and J. Elliott Campbell
Biogeosciences, 15, 3625–3657, https://doi.org/10.5194/bg-15-3625-2018, https://doi.org/10.5194/bg-15-3625-2018, 2018
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Measurements of the trace gas carbonyl sulfide (OCS) are helpful in quantifying photosynthesis at previously unknowable temporal and spatial scales. While CO2 is both consumed and produced within ecosystems, OCS is mostly produced in the oceans or from specific industries, and destroyed in plant leaves in proportion to CO2. This review summarizes the advancements we have made in the understanding of OCS exchange and applications to vital ecosystem water and carbon cycle questions.
Marco Pandolfi, Lucas Alados-Arboledas, Andrés Alastuey, Marcos Andrade, Christo Angelov, Begoña Artiñano, John Backman, Urs Baltensperger, Paolo Bonasoni, Nicolas Bukowiecki, Martine Collaud Coen, Sébastien Conil, Esther Coz, Vincent Crenn, Vadimas Dudoitis, Marina Ealo, Kostas Eleftheriadis, Olivier Favez, Prodromos Fetfatzis, Markus Fiebig, Harald Flentje, Patrick Ginot, Martin Gysel, Bas Henzing, Andras Hoffer, Adela Holubova Smejkalova, Ivo Kalapov, Nikos Kalivitis, Giorgos Kouvarakis, Adam Kristensson, Markku Kulmala, Heikki Lihavainen, Chris Lunder, Krista Luoma, Hassan Lyamani, Angela Marinoni, Nikos Mihalopoulos, Marcel Moerman, José Nicolas, Colin O'Dowd, Tuukka Petäjä, Jean-Eudes Petit, Jean Marc Pichon, Nina Prokopciuk, Jean-Philippe Putaud, Sergio Rodríguez, Jean Sciare, Karine Sellegri, Erik Swietlicki, Gloria Titos, Thomas Tuch, Peter Tunved, Vidmantas Ulevicius, Aditya Vaishya, Milan Vana, Aki Virkkula, Stergios Vratolis, Ernest Weingartner, Alfred Wiedensohler, and Paolo Laj
Atmos. Chem. Phys., 18, 7877–7911, https://doi.org/10.5194/acp-18-7877-2018, https://doi.org/10.5194/acp-18-7877-2018, 2018
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This investigation presents the variability in near-surface in situ aerosol particle light-scattering measurements obtained over the past decade at 28 measuring atmospheric observatories which are part of the ACTRIS Research Infrastructure, and most of them belong to the GAW network. This paper provides a comprehensive picture of the spatial and temporal variability of aerosol particles optical properties in Europe.
Vladimir Melnikov, Viktor Gennadinik, Markku Kulmala, Hanna K. Lappalainen, Tuukka Petäjä, and Sergej Zilitinkevich
Atmos. Chem. Phys., 18, 6535–6542, https://doi.org/10.5194/acp-18-6535-2018, https://doi.org/10.5194/acp-18-6535-2018, 2018
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The cryosphere of the Earth overlaps with the atmosphere, hydrosphere and lithosphere over vast areas with temperatures below zero C and pronounced H2O phase changes. The cryosphere plays the role of a global thermostat; however, the processes related to the cryosphere attract insufficient attention from research communities. We call attention to crucial importance of cryogenic anomalies, which make the Earth atmosphere and the entire Earth system unique.
Marja Hemmilä, Heidi Hellén, Aki Virkkula, Ulla Makkonen, Arnaud P. Praplan, Jenni Kontkanen, Lauri Ahonen, Markku Kulmala, and Hannele Hakola
Atmos. Chem. Phys., 18, 6367–6380, https://doi.org/10.5194/acp-18-6367-2018, https://doi.org/10.5194/acp-18-6367-2018, 2018
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We measured gas- and particle-phase amine and ammonia concentrations in a boreal forest site in 2015 with online ion chromatography coupled with mass spectrometry. We wanted to know how much and which kinds of amines there are, and how they behave and could affect nucleation. We observed seasonal and diurnal variations for different amines. Amines turned out to be a heterogeneous group of compounds. To our best knowledge, our amine measurements are the longest time series that has been made.
Yicheng Shen, Aki Virkkula, Aijun Ding, Jiaping Wang, Xuguang Chi, Wei Nie, Ximeng Qi, Xin Huang, Qiang Liu, Longfei Zheng, Zheng Xu, Tuukka Petäjä, Pasi P. Aalto, Congbin Fu, and Markku Kulmala
Atmos. Chem. Phys., 18, 5265–5292, https://doi.org/10.5194/acp-18-5265-2018, https://doi.org/10.5194/acp-18-5265-2018, 2018
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Aerosol optical properties (AOPs) were measured at SORPES, a regional background station in Nanjing, China from June 2013 to May 2015. The aerosol was highly scattering. The single-scattering albedo in Nanjing appears to be slightly higher than at several other sites. The data do not suggest any significant contribution to absorption by brown carbon. The sources of high values are mainly in eastern China. During pollution episodes, pollutant concentrations increased gradually but decreased fast.
Maria Provenzale, Anne Ojala, Jouni Heiskanen, Kukka-Maaria Erkkilä, Ivan Mammarella, Pertti Hari, and Timo Vesala
Biogeosciences, 15, 2021–2032, https://doi.org/10.5194/bg-15-2021-2018, https://doi.org/10.5194/bg-15-2021-2018, 2018
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We extensively tested and refined a direct, high-frequency free-water CO2 measurement method to study the lake net ecosystem productivity. The method was first proposed in 2008, but neglected ever since.
With high-frequency direct methods, we can calculate the lake productivity more precisely, and parameterise its dependency on environmental variables. This helps us expand our knowledge on the carbon cycle in the water, and leads to a better integration of water bodies in carbon budgets.
Joonas Enroth, Jyri Mikkilä, Zoltán Németh, Markku Kulmala, and Imre Salma
Atmos. Chem. Phys., 18, 4533–4548, https://doi.org/10.5194/acp-18-4533-2018, https://doi.org/10.5194/acp-18-4533-2018, 2018
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The urban aerosol particles in central Budapest consist of two externally mixed classes – nearly hydrophobic and less volatile particles, which were assigned to vehicle emissions (large mass fractions of soot likely coated with water-insoluble organic compounds) – and of less hygroscopic and volatile particles (moderately transformed aged combustion particles composed of partly oxygenated organics and inorganic salts internally mixed).
Aino Korrensalo, Elisa Männistö, Pavel Alekseychik, Ivan Mammarella, Janne Rinne, Timo Vesala, and Eeva-Stiina Tuittila
Biogeosciences, 15, 1749–1761, https://doi.org/10.5194/bg-15-1749-2018, https://doi.org/10.5194/bg-15-1749-2018, 2018
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We measured methane fluxes of a boreal bog from six different plant community types in 2012–2014. We found only little variation in methane fluxes among plant community types. Peat temperature as well as both leaf area of plant species with air channels and of all vegetation are important factors controlling the fluxes. We also detected negative net fluxes indicating methane consumption each year. Our results can be used to improve the models of peatland methane dynamics under climate change.
Marta Camino-Serrano, Bertrand Guenet, Sebastiaan Luyssaert, Philippe Ciais, Vladislav Bastrikov, Bruno De Vos, Bert Gielen, Gerd Gleixner, Albert Jornet-Puig, Klaus Kaiser, Dolly Kothawala, Ronny Lauerwald, Josep Peñuelas, Marion Schrumpf, Sara Vicca, Nicolas Vuichard, David Walmsley, and Ivan A. Janssens
Geosci. Model Dev., 11, 937–957, https://doi.org/10.5194/gmd-11-937-2018, https://doi.org/10.5194/gmd-11-937-2018, 2018
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Global models generally oversimplify the representation of soil organic carbon (SOC), and thus its response to global warming remains uncertain. We present the new soil module ORCHIDEE-SOM, within the global model ORCHIDEE, that refines the representation of SOC dynamics and includes the dissolved organic carbon (DOC) processes. The model is able to reproduce SOC stocks and DOC concentrations in four different ecosystems, opening an opportunity for improved predictions of SOC in global models.
Julia Schmale, Silvia Henning, Stefano Decesari, Bas Henzing, Helmi Keskinen, Karine Sellegri, Jurgita Ovadnevaite, Mira L. Pöhlker, Joel Brito, Aikaterini Bougiatioti, Adam Kristensson, Nikos Kalivitis, Iasonas Stavroulas, Samara Carbone, Anne Jefferson, Minsu Park, Patrick Schlag, Yoko Iwamoto, Pasi Aalto, Mikko Äijälä, Nicolas Bukowiecki, Mikael Ehn, Göran Frank, Roman Fröhlich, Arnoud Frumau, Erik Herrmann, Hartmut Herrmann, Rupert Holzinger, Gerard Kos, Markku Kulmala, Nikolaos Mihalopoulos, Athanasios Nenes, Colin O'Dowd, Tuukka Petäjä, David Picard, Christopher Pöhlker, Ulrich Pöschl, Laurent Poulain, André Stephan Henry Prévôt, Erik Swietlicki, Meinrat O. Andreae, Paulo Artaxo, Alfred Wiedensohler, John Ogren, Atsushi Matsuki, Seong Soo Yum, Frank Stratmann, Urs Baltensperger, and Martin Gysel
Atmos. Chem. Phys., 18, 2853–2881, https://doi.org/10.5194/acp-18-2853-2018, https://doi.org/10.5194/acp-18-2853-2018, 2018
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Collocated long-term observations of cloud condensation nuclei (CCN) number concentrations, particle number size distributions and chemical composition from 12 sites are synthesized. Observations cover coastal environments, the Arctic, the Mediterranean, the boreal and rain forest, high alpine and continental background sites, and Monsoon-influenced areas. We interpret regional and seasonal variability. CCN concentrations are predicted with the κ–Köhler model and compared to the measurements.
Nina Sarnela, Tuija Jokinen, Jonathan Duplissy, Chao Yan, Tuomo Nieminen, Mikael Ehn, Siegfried Schobesberger, Martin Heinritzi, Sebastian Ehrhart, Katrianne Lehtipalo, Jasmin Tröstl, Mario Simon, Andreas Kürten, Markus Leiminger, Michael J. Lawler, Matti P. Rissanen, Federico Bianchi, Arnaud P. Praplan, Jani Hakala, Antonio Amorim, Marc Gonin, Armin Hansel, Jasper Kirkby, Josef Dommen, Joachim Curtius, James N. Smith, Tuukka Petäjä, Douglas R. Worsnop, Markku Kulmala, Neil M. Donahue, and Mikko Sipilä
Atmos. Chem. Phys., 18, 2363–2380, https://doi.org/10.5194/acp-18-2363-2018, https://doi.org/10.5194/acp-18-2363-2018, 2018
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Atmospheric trace gases can form small molecular clusters, which can grow to larger sizes through the condensation of vapours. This process is called new particle formation. In this paper we studied the formation of sulfuric acid and highly oxygenated molecules, the key compounds in atmospheric new particle formation, in chamber experiments and introduced a way to simulate these ozonolysis products of α-pinene in a simple manner.
Ekaterina Ezhova, Veli-Matti Kerminen, Kari E. J. Lehtinen, and Markku Kulmala
Atmos. Chem. Phys., 18, 2431–2442, https://doi.org/10.5194/acp-18-2431-2018, https://doi.org/10.5194/acp-18-2431-2018, 2018
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A condensation sink (CS) quantifies the rate of uptake of condensing vapours by pre-existing aerosol and can be used as well to quantify losses of monomers/clusters. An analytical solution of the condensation equation valid in a wide range of particle diameters is presented. We describe the dynamics of atmospheric CS, test the formulas against field observations and further use them to develop a simplified model of the coupled dynamics of aerosol and condensing vapours in the atmosphere.
Luís Miguel Feijó Barreira, Geoffroy Duporté, Tuukka Rönkkö, Jevgeni Parshintsev, Kari Hartonen, Lydia Hyrsky, Enna Heikkinen, Matti Jussila, Markku Kulmala, and Marja-Liisa Riekkola
Atmos. Meas. Tech., 11, 881–893, https://doi.org/10.5194/amt-11-881-2018, https://doi.org/10.5194/amt-11-881-2018, 2018
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Our results demonstrated the benefits and challenges of using new SPME Arrow over SPME fiber for the sampling of BVOCs emitted by terrestrial vegetation in the atmosphere. The new SPME Arrow system showed significant improvement on sampling capacity, with collected amounts being approximately 2 times higher for monoterpenes and 7–8 times higher for aldehydes than with SPME fiber. Higher extraction efficiencies were obtained with dynamic collection prior to equilibrium regime.
Mahdi Nakhavali, Pierre Friedlingstein, Ronny Lauerwald, Jing Tang, Sarah Chadburn, Marta Camino-Serrano, Bertrand Guenet, Anna Harper, David Walmsley, Matthias Peichl, and Bert Gielen
Geosci. Model Dev., 11, 593–609, https://doi.org/10.5194/gmd-11-593-2018, https://doi.org/10.5194/gmd-11-593-2018, 2018
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In order to provide a better understanding of the Earth's carbon cycle, we need a model that represents the whole continuum from atmosphere to land and into the ocean. In this study we include in JULES a representation of dissolved organic carbon (DOC) processes. Our results show that the model is able to reproduce the DOC concentration and controlling processes, including leaching to the riverine system, which is fundamental for integrating the terrestrial and aquatic ecosystem.
Johannes Größ, Amar Hamed, André Sonntag, Gerald Spindler, Hanna Elina Manninen, Tuomo Nieminen, Markku Kulmala, Urmas Hõrrak, Christian Plass-Dülmer, Alfred Wiedensohler, and Wolfram Birmili
Atmos. Chem. Phys., 18, 1835–1861, https://doi.org/10.5194/acp-18-1835-2018, https://doi.org/10.5194/acp-18-1835-2018, 2018
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This paper revisits the atmospheric new particle formation (NPF) process in the polluted troposphere. Novel aspects include a new NPF classification, which aims at more objectivity, and a long-term analysis of neutral cluster and air ion spectrometer data. Intense NPF events were associated with enhanced sulfur dioxide concentrations and solar radiation, while no significant relationships were observed with the condensation sink, surface-measured turbulence parameters, or ammonia.
Chunjing Qiu, Dan Zhu, Philippe Ciais, Bertrand Guenet, Gerhard Krinner, Shushi Peng, Mika Aurela, Christian Bernhofer, Christian Brümmer, Syndonia Bret-Harte, Housen Chu, Jiquan Chen, Ankur R. Desai, Jiří Dušek, Eugénie S. Euskirchen, Krzysztof Fortuniak, Lawrence B. Flanagan, Thomas Friborg, Mateusz Grygoruk, Sébastien Gogo, Thomas Grünwald, Birger U. Hansen, David Holl, Elyn Humphreys, Miriam Hurkuck, Gerard Kiely, Janina Klatt, Lars Kutzbach, Chloé Largeron, Fatima Laggoun-Défarge, Magnus Lund, Peter M. Lafleur, Xuefei Li, Ivan Mammarella, Lutz Merbold, Mats B. Nilsson, Janusz Olejnik, Mikaell Ottosson-Löfvenius, Walter Oechel, Frans-Jan W. Parmentier, Matthias Peichl, Norbert Pirk, Olli Peltola, Włodzimierz Pawlak, Daniel Rasse, Janne Rinne, Gaius Shaver, Hans Peter Schmid, Matteo Sottocornola, Rainer Steinbrecher, Torsten Sachs, Marek Urbaniak, Donatella Zona, and Klaudia Ziemblinska
Geosci. Model Dev., 11, 497–519, https://doi.org/10.5194/gmd-11-497-2018, https://doi.org/10.5194/gmd-11-497-2018, 2018
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Northern peatlands store large amount of soil carbon and are vulnerable to climate change. We implemented peatland hydrological and carbon accumulation processes into the ORCHIDEE land surface model. The model was evaluated against EC measurements from 30 northern peatland sites. The model generally well reproduced the spatial gradient and temporal variations in GPP and NEE at these sites. Water table depth was not well predicted but had only small influence on simulated NEE.
Wu Sun, Linda M. J. Kooijmans, Kadmiel Maseyk, Huilin Chen, Ivan Mammarella, Timo Vesala, Janne Levula, Helmi Keskinen, and Ulli Seibt
Atmos. Chem. Phys., 18, 1363–1378, https://doi.org/10.5194/acp-18-1363-2018, https://doi.org/10.5194/acp-18-1363-2018, 2018
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Most soils consume carbonyl sulfide (COS) and CO due to microbial uptake, but whether boreal forest soils act like this is uncertain. We measured growing season soil COS and CO fluxes in a Finnish pine forest. The soil behaved as a consistent and relatively invariant sink of COS and CO. Uptake rates of COS and CO decrease with soil moisture due to diffusion limitation and increase with respiration because of microbial control. Using COS to infer photosynthesis is not affected by soil COS flux.
Mari Mäki, Hermanni Aaltonen, Jussi Heinonsalo, Heidi Hellén, Jukka Pumpanen, and Jaana Bäck
Biogeosciences Discuss., https://doi.org/10.5194/bg-2018-22, https://doi.org/10.5194/bg-2018-22, 2018
Preprint withdrawn
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Vegetation emissions of volatile organic compounds (VOCs) are intensively studied world-wide, but remains largely unknown how effectively belowground VOCs are produced and released into the atmosphere. We demonstrate that boreal forest soil is a diverse source and storage of VOCs, because more than 50 VOCs were detected in the soil air. Our results give evidence that VOC production processes and storages partly differ from those VOCs that are simultaneously emitted from the soil surface.
Simon Schallhart, Pekka Rantala, Maija K. Kajos, Juho Aalto, Ivan Mammarella, Taina M. Ruuskanen, and Markku Kulmala
Atmos. Chem. Phys., 18, 815–832, https://doi.org/10.5194/acp-18-815-2018, https://doi.org/10.5194/acp-18-815-2018, 2018
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Emissions of volatile organic compounds (VOCs) have impact to air quality, human health and climate. We investigated the development of VOC exchange in a boreal forest between April and June 2013. VOC exchange and diversity increased towards summer, but over 75 % of the biogenic net exchange was driven by methanol, monoterpenes and acetone only. The boreal forest emitted less than 0.2 % carbon in form of VOCs in relation to the carbon uptake.
Andreas Kürten, Chenxi Li, Federico Bianchi, Joachim Curtius, António Dias, Neil M. Donahue, Jonathan Duplissy, Richard C. Flagan, Jani Hakala, Tuija Jokinen, Jasper Kirkby, Markku Kulmala, Ari Laaksonen, Katrianne Lehtipalo, Vladimir Makhmutov, Antti Onnela, Matti P. Rissanen, Mario Simon, Mikko Sipilä, Yuri Stozhkov, Jasmin Tröstl, Penglin Ye, and Peter H. McMurry
Atmos. Chem. Phys., 18, 845–863, https://doi.org/10.5194/acp-18-845-2018, https://doi.org/10.5194/acp-18-845-2018, 2018
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A recent laboratory study (CLOUD) showed that new particles nucleate efficiently from sulfuric acid and dimethylamine (DMA). The reanalysis of previously published data reveals that the nucleation rates are even faster than previously assumed, i.e., nucleation can proceed at rates that are compatible with collision-controlled new particle formation for atmospheric conditions. This indicates that sulfuric acid–DMA nucleation is likely an important source of particles in the boundary layer.
Kukka-Maaria Erkkilä, Anne Ojala, David Bastviken, Tobias Biermann, Jouni J. Heiskanen, Anders Lindroth, Olli Peltola, Miitta Rantakari, Timo Vesala, and Ivan Mammarella
Biogeosciences, 15, 429–445, https://doi.org/10.5194/bg-15-429-2018, https://doi.org/10.5194/bg-15-429-2018, 2018
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Global estimates of freshwater greenhouse gas emissions are usually based on simple gas transfer models that underestimate the emissions. Thus, comparison of different gas transfer models is required for evaluating the uncertainties. This study compares three commonly used methods for estimating greenhouse gas emissions over lakes. We conclude that simple gas transfer models underestimate the emissions and more recent models should be used for global freshwater greenhouse gas emission estimates.
Carla Frege, Ismael K. Ortega, Matti P. Rissanen, Arnaud P. Praplan, Gerhard Steiner, Martin Heinritzi, Lauri Ahonen, António Amorim, Anne-Kathrin Bernhammer, Federico Bianchi, Sophia Brilke, Martin Breitenlechner, Lubna Dada, António Dias, Jonathan Duplissy, Sebastian Ehrhart, Imad El-Haddad, Lukas Fischer, Claudia Fuchs, Olga Garmash, Marc Gonin, Armin Hansel, Christopher R. Hoyle, Tuija Jokinen, Heikki Junninen, Jasper Kirkby, Andreas Kürten, Katrianne Lehtipalo, Markus Leiminger, Roy Lee Mauldin, Ugo Molteni, Leonid Nichman, Tuukka Petäjä, Nina Sarnela, Siegfried Schobesberger, Mario Simon, Mikko Sipilä, Dominik Stolzenburg, António Tomé, Alexander L. Vogel, Andrea C. Wagner, Robert Wagner, Mao Xiao, Chao Yan, Penglin Ye, Joachim Curtius, Neil M. Donahue, Richard C. Flagan, Markku Kulmala, Douglas R. Worsnop, Paul M. Winkler, Josef Dommen, and Urs Baltensperger
Atmos. Chem. Phys., 18, 65–79, https://doi.org/10.5194/acp-18-65-2018, https://doi.org/10.5194/acp-18-65-2018, 2018
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It was recently shown that biogenic highly oxygenated molecules (HOMs) form particles in the absence of sulfuric acid and ions enhance the nucleation rate. Here we compare the molecular composition of positive and negative HOM clusters at 25, 5 and −25 °C. At lower temperatures the HOM average oxygen-to-carbon ratio decreases indicating a reduction in the rate of autoxidation due to rather high activation energy. The experimental findings are supported by quantum chemical calculations.
Xuemeng Chen, Lauriane L. J. Quéléver, Pak L. Fung, Jutta Kesti, Matti P. Rissanen, Jaana Bäck, Petri Keronen, Heikki Junninen, Tuukka Petäjä, Veli-Matti Kerminen, and Markku Kulmala
Atmos. Chem. Phys., 18, 49–63, https://doi.org/10.5194/acp-18-49-2018, https://doi.org/10.5194/acp-18-49-2018, 2018
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We analysed a 20-year-long dataset collected in a Finnish boreal forest at SMEAR II station to investigate the frequency and strength of ozone depletion events. We could identify a number of ozone depletion events that lasted for more than 3 h, mainly in the autumn and winter months. Their occurrence was likely related to the formation of a low mixing layer under the conditions of low temperatures, low wind speeds, high relative humidities and limited intensity of solar radiation.
Robert Wagner, Chao Yan, Katrianne Lehtipalo, Jonathan Duplissy, Tuomo Nieminen, Juha Kangasluoma, Lauri R. Ahonen, Lubna Dada, Jenni Kontkanen, Hanna E. Manninen, Antonio Dias, Antonio Amorim, Paulus S. Bauer, Anton Bergen, Anne-Kathrin Bernhammer, Federico Bianchi, Sophia Brilke, Stephany Buenrostro Mazon, Xuemeng Chen, Danielle C. Draper, Lukas Fischer, Carla Frege, Claudia Fuchs, Olga Garmash, Hamish Gordon, Jani Hakala, Liine Heikkinen, Martin Heinritzi, Victoria Hofbauer, Christopher R. Hoyle, Jasper Kirkby, Andreas Kürten, Alexander N. Kvashnin, Tiia Laurila, Michael J. Lawler, Huajun Mai, Vladimir Makhmutov, Roy L. Mauldin III, Ugo Molteni, Leonid Nichman, Wei Nie, Andrea Ojdanic, Antti Onnela, Felix Piel, Lauriane L. J. Quéléver, Matti P. Rissanen, Nina Sarnela, Simon Schallhart, Kamalika Sengupta, Mario Simon, Dominik Stolzenburg, Yuri Stozhkov, Jasmin Tröstl, Yrjö Viisanen, Alexander L. Vogel, Andrea C. Wagner, Mao Xiao, Penglin Ye, Urs Baltensperger, Joachim Curtius, Neil M. Donahue, Richard C. Flagan, Martin Gallagher, Armin Hansel, James N. Smith, António Tomé, Paul M. Winkler, Douglas Worsnop, Mikael Ehn, Mikko Sipilä, Veli-Matti Kerminen, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 17, 15181–15197, https://doi.org/10.5194/acp-17-15181-2017, https://doi.org/10.5194/acp-17-15181-2017, 2017
Pertti Hari, Veli-Matti Kerminen, Liisa Kulmala, Markku Kulmala, Steffen Noe, Tuukka Petäjä, Anni Vanhatalo, and Jaana Bäck
Atmos. Chem. Phys., 17, 15045–15053, https://doi.org/10.5194/acp-17-15045-2017, https://doi.org/10.5194/acp-17-15045-2017, 2017
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We developed a theory on the seasonal behaviour of photosynthesis in natural conditions and tested the theory with intensive measurements. Light, temperature, water vapor and CO2 concentration explained the daily variation in photosynthesis, and the physiological state of the photosynthetic machinery explained the annual pattern of photosynthesis. The theory explained about 95 % of the variance of photosynthesis measured with chambers in the field in northern Finland.
Mathilde Jammet, Sigrid Dengel, Ernesto Kettner, Frans-Jan W. Parmentier, Martin Wik, Patrick Crill, and Thomas Friborg
Biogeosciences, 14, 5189–5216, https://doi.org/10.5194/bg-14-5189-2017, https://doi.org/10.5194/bg-14-5189-2017, 2017
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The quantitative importance of northern lakes in terrestrial carbon budgets is uncertain, as year-round observations of carbon fluxes are rare. We measured CH4 and CO2 fluxes from a subarctic lake and nearby fen during 2.5 years with one eddy covariance system. We identified drivers of seasonal variability in lake fluxes and show the importance of winter and spring for annual carbon exchange in both ecosystems. The lake as a source of atmospheric carbon partially compensates the fen carbon sink.
Xuemeng Chen, Aki Virkkula, Veli-Matti Kerminen, Hanna E. Manninen, Maurizio Busetto, Christian Lanconelli, Angelo Lupi, Vito Vitale, Massimo Del Guasta, Paolo Grigioni, Riikka Väänänen, Ella-Maria Duplissy, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 17, 13783–13800, https://doi.org/10.5194/acp-17-13783-2017, https://doi.org/10.5194/acp-17-13783-2017, 2017
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An air ion spectrometer was deployed for characterizing air ions for the first time at the Concordia station at Dome C on the Antarctic Plateau. We observed different ion processes: new particle formation (NPF), wind-induced ion production, and ion formation related to cloud and/or fog formation. Insights into these phenomena are presented. Additionally, the analysis on the growth of NPF events showed a size dependency of growth rates (GRs), i.e. GRs increase with particle sizes.
Federico Bianchi, Olga Garmash, Xucheng He, Chao Yan, Siddharth Iyer, Ida Rosendahl, Zhengning Xu, Matti P. Rissanen, Matthieu Riva, Risto Taipale, Nina Sarnela, Tuukka Petäjä, Douglas R. Worsnop, Markku Kulmala, Mikael Ehn, and Heikki Junninen
Atmos. Chem. Phys., 17, 13819–13831, https://doi.org/10.5194/acp-17-13819-2017, https://doi.org/10.5194/acp-17-13819-2017, 2017
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Naturally charged highly oxidised molecules (HOMs) were characterized using advanced mass spectrometers. Two different classes of compounds, clustered with the nitrate and bisulfate ions, were identified: HOMs containing only carbon, hydrogen and oxygen and nitrogen-containing HOMs or organonitrates (ONs). They exhibit strong diurnal variations where HOMs peak during night and ONs during day. Finally, large clusters containing up to 40 carbon atoms (four oxidized
α-pinene units) were observed.
Elham Baranizadeh, Tuomo Nieminen, Taina Yli-Juuti, Markku Kulmala, Tuukka Petäjä, Ari Leskinen, Mika Komppula, Ari Laaksonen, and Kari E. J. Lehtinen
Atmos. Chem. Phys., 17, 13361–13371, https://doi.org/10.5194/acp-17-13361-2017, https://doi.org/10.5194/acp-17-13361-2017, 2017
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Extrapolation of the particle formation rates from one measured larger size (e.g., 7 nm) to smaller sizes (e.g., 3 nm) based on simplified growth-scavenging dynamics works fairly well to estimate mean daily formation rates, but it fails to predict the time evolution of the particle population. This points to the challenges in predicting atmospheric nucleation rates for locations where the particle growth and loss rates are size- and time-dependent.
Aku Helin, Outi-Maaria Sietiö, Jussi Heinonsalo, Jaana Bäck, Marja-Liisa Riekkola, and Jevgeni Parshintsev
Atmos. Chem. Phys., 17, 13089–13101, https://doi.org/10.5194/acp-17-13089-2017, https://doi.org/10.5194/acp-17-13089-2017, 2017
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Bioaerosols are ubiquitous in the atmosphere and may affect the cloud and precipitation formation processes. In this study, size-segregated aerosol samples were collected in boreal forest during 1 year and analysed for free amino acids, deoxyribonucleic acid, bacteria and fungi. Distinct annual patterns of bioaerosol components were observed. Also, air and soil temperature, radiation and rainfall were observed to possess a close relationship with bioaerosol abundances on an annual scale.
Yao Gao, Tiina Markkanen, Mika Aurela, Ivan Mammarella, Tea Thum, Aki Tsuruta, Huiyi Yang, and Tuula Aalto
Biogeosciences, 14, 4409–4422, https://doi.org/10.5194/bg-14-4409-2017, https://doi.org/10.5194/bg-14-4409-2017, 2017
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We investigated the response of water use efficiency (WUE) to summer drought in a boreal Scots pine forest (Pinus sylvestris) on the daily time scale mainly using EC flux data from the Hyytiälä (southern Finland) flux site. Simulation results from the JSBACH land surface model were also evaluated against the observed results. The performance of three WUE metrics at the ecosystem level (EWUE, IWUE, and uWUE) during the severe summer drought were studied and showed different results.
Linda M. J. Kooijmans, Kadmiel Maseyk, Ulli Seibt, Wu Sun, Timo Vesala, Ivan Mammarella, Pasi Kolari, Juho Aalto, Alessandro Franchin, Roberta Vecchi, Gianluigi Valli, and Huilin Chen
Atmos. Chem. Phys., 17, 11453–11465, https://doi.org/10.5194/acp-17-11453-2017, https://doi.org/10.5194/acp-17-11453-2017, 2017
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Carbon cycle studies rely on the accuracy of models to estimate the amount of CO2 being taken up by vegetation. The gas carbonyl sulfide (COS) can serve as a tool to estimate the vegetative CO2 uptake by scaling the ecosystem uptake of COS to that of CO2. Here we investigate the nighttime fluxes of COS. The relationships found in this study will aid in implementing nighttime COS uptake in models, which is key to obtain accurate estimates of vegetative CO2 uptake with the use of COS.
Ylva van Meeningen, Guy Schurgers, Riikka Rinnan, and Thomas Holst
Biogeosciences, 14, 4045–4060, https://doi.org/10.5194/bg-14-4045-2017, https://doi.org/10.5194/bg-14-4045-2017, 2017
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Leaf scale measurements have been performed on English oak, European beech and Norway spruce at a field site in Denmark to study the release of volatile compounds in response to a change in light. Whilst some compounds, like isoprene and sabinene, increased with increasing light, other compounds, like camphene, showed no light response for most of the trees. This can help to increase our knowledge of how species and compounds respond to light and to possibly improve how they can be modeled.
Pavel Alekseychik, Ivan Mammarella, Dmitry Karpov, Sigrid Dengel, Irina Terentieva, Alexander Sabrekov, Mikhail Glagolev, and Elena Lapshina
Atmos. Chem. Phys., 17, 9333–9345, https://doi.org/10.5194/acp-17-9333-2017, https://doi.org/10.5194/acp-17-9333-2017, 2017
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West Siberian peatlands occupy a large fraction of land area in the region, and yet little is known about their interaction with the atmosphere. We took the first measurements of CO2 and energy surface balances over a typical bog of West Siberian middle taiga, in the vicinity of the Mukhrino field station (Khanty–Mansiysk). The May–August study in a wet year (2015) revealed a relatively large photosynthetic sink of CO2 that was close to the high end of estimates at bog sites elsewhere.
Georgios Tsagkogeorgas, Pontus Roldin, Jonathan Duplissy, Linda Rondo, Jasmin Tröstl, Jay G. Slowik, Sebastian Ehrhart, Alessandro Franchin, Andreas Kürten, Antonio Amorim, Federico Bianchi, Jasper Kirkby, Tuukka Petäjä, Urs Baltensperger, Michael Boy, Joachim Curtius, Richard C. Flagan, Markku Kulmala, Neil M. Donahue, and Frank Stratmann
Atmos. Chem. Phys., 17, 8923–8938, https://doi.org/10.5194/acp-17-8923-2017, https://doi.org/10.5194/acp-17-8923-2017, 2017
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The H2SO4 vapour pressure plays key role in Earth's and Venus' atmospheres. In regions where RH is low and stabilising bases are scarce, H2SO4 can evaporate from particles; however the H2SO4 vapour pressure at low RH is uncertain. To address this, we measured H2SO4 evaporation versus T and RH in the CLOUD chamber and constrained the equilibrium constants for dissociation and dehydration of H2SO4. This study is important for nucleation, particle growth and H2SO4 formation occurring in atmosphere.
Emilie Öström, Zhou Putian, Guy Schurgers, Mikhail Mishurov, Niku Kivekäs, Heikki Lihavainen, Mikael Ehn, Matti P. Rissanen, Theo Kurtén, Michael Boy, Erik Swietlicki, and Pontus Roldin
Atmos. Chem. Phys., 17, 8887–8901, https://doi.org/10.5194/acp-17-8887-2017, https://doi.org/10.5194/acp-17-8887-2017, 2017
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We used a model to study how biogenic volatile organic compounds (BVOCs) emitted from the boreal forest contribute to the formation and growth of particles in the atmosphere. Some of these particles are important climate forcers, acting as seeds for cloud droplet fomation. We implemented a new gas chemistry mechanism that describes how the BVOCs are oxidized and form low-volatility highly oxidized organic molecules. With the new mechanism we are able to accurately predict the particle growth.
Anna Novelli, Korbinian Hens, Cheryl Tatum Ernest, Monica Martinez, Anke C. Nölscher, Vinayak Sinha, Pauli Paasonen, Tuukka Petäjä, Mikko Sipilä, Thomas Elste, Christian Plass-Dülmer, Gavin J. Phillips, Dagmar Kubistin, Jonathan Williams, Luc Vereecken, Jos Lelieveld, and Hartwig Harder
Atmos. Chem. Phys., 17, 7807–7826, https://doi.org/10.5194/acp-17-7807-2017, https://doi.org/10.5194/acp-17-7807-2017, 2017
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The ambient concentration of stabilised Criegee intermediates (SCIs) was estimated for two
environments using field data. The low concentrations predicted indicate that SCIs are
unlikely to have a large impact on atmospheric chemistry. Concurrent measurements of an OH background signal using the Mainz IPI-LIF-FAGE instrument were found to be consistent with the chemistry of SCIs during the measurement campaigns.
Juha Kangasluoma, Susanne Hering, David Picard, Gregory Lewis, Joonas Enroth, Frans Korhonen, Markku Kulmala, Karine Sellegri, Michel Attoui, and Tuukka Petäjä
Atmos. Meas. Tech., 10, 2271–2281, https://doi.org/10.5194/amt-10-2271-2017, https://doi.org/10.5194/amt-10-2271-2017, 2017
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The manuscript presents a characterization of three new particle counters able to detect airborne nanoparticles smaller than 3 nm in diameter. We explored some of the parameters affecting the smallest detectable particle size, such as sample flow relative humidity, the particle chemical composition and the electrical charging state. The characterization results help one to select a suitable particle counter for a given application.
Lubna Dada, Pauli Paasonen, Tuomo Nieminen, Stephany Buenrostro Mazon, Jenni Kontkanen, Otso Peräkylä, Katrianne Lehtipalo, Tareq Hussein, Tuukka Petäjä, Veli-Matti Kerminen, Jaana Bäck, and Markku Kulmala
Atmos. Chem. Phys., 17, 6227–6241, https://doi.org/10.5194/acp-17-6227-2017, https://doi.org/10.5194/acp-17-6227-2017, 2017
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We studied new particle formation under clear-sky conditions in the boreal forest in southern Finland. We compared varying conditions between new particle events and nonevents. We then formulated a threshold value that separates new particle events from nonevents and reached a probability distribution for the frequency of new particle formation. This study serves as the basis for scientists aiming to improve their understanding of new particle formation.
Kgaugelo Euphinia Chiloane, Johan Paul Beukes, Pieter Gideon van Zyl, Petra Maritz, Ville Vakkari, Miroslav Josipovic, Andrew Derick Venter, Kerneels Jaars, Petri Tiitta, Markku Kulmala, Alfred Wiedensohler, Catherine Liousse, Gabisile Vuyisile Mkhatshwa, Avishkar Ramandh, and Lauri Laakso
Atmos. Chem. Phys., 17, 6177–6196, https://doi.org/10.5194/acp-17-6177-2017, https://doi.org/10.5194/acp-17-6177-2017, 2017
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This paper presents atmospheric black carbon (BC) data collected in South Africa (SA). In general, BC level were higher than in the developed world. At one site, five sources were identified, with household combustion as well as savannah and grassland fires the most significant sources during winter and spring, while coal-fired power stations, pyrometallurgical smelters and traffic contributed year round.
Eero Nikinmaa, Tuomo Kalliokoski, Kari Minkkinen, Jaana Bäck, Michael Boy, Yao Gao, Nina Janasik-Honkela, Janne I. Hukkinen, Maarit Kallio, Markku Kulmala, Nea Kuusinen, Annikki Mäkelä, Brent D. Matthies, Mikko Peltoniemi, Risto Sievänen, Ditte Taipale, Lauri Valsta, Anni Vanhatalo, Martin Welp, Luxi Zhou, Putian Zhou, and Frank Berninger
Biogeosciences Discuss., https://doi.org/10.5194/bg-2017-141, https://doi.org/10.5194/bg-2017-141, 2017
Manuscript not accepted for further review
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We estimated the impact of boreal forest management on climate, considering the effects of carbon, albedo, aerosols, and effects of industrial wood use. We made analyses both in current and warmer climate of 2050. The aerosol effect was comparable to that of carbon sequestration. Deciduous trees may have a large potential for mitigation due to their high albedo and aerosol effects. If the forests will be used more intensively and mainly for pulp and energy, the warming influence is clear.
Yuqin Liu, Gerrit de Leeuw, Veli-Matti Kerminen, Jiahua Zhang, Putian Zhou, Wei Nie, Ximeng Qi, Juan Hong, Yonghong Wang, Aijun Ding, Huadong Guo, Olaf Krüger, Markku Kulmala, and Tuukka Petäjä
Atmos. Chem. Phys., 17, 5623–5641, https://doi.org/10.5194/acp-17-5623-2017, https://doi.org/10.5194/acp-17-5623-2017, 2017
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The aerosol effects on warm cloud parameters over the Yangtze River Delta are systematically examined using multi-sensor retrievals. This study shows that the COT–CDR and CWP–CDR relationships are not unique, but are affected by atmospheric aerosol loading. CDR and cloud fraction show different behaviours for low and high AOD. Aerosol–cloud interaction (ACI) is stronger for clouds mixed with smoke aerosol than for clouds mixed with dust. Meteorological conditions play an important role in ACI.
Elisângela Broedel, Celso Von Randow, Luz Adriana Cuartas, Antonio Donato Nobre, Alessandro Carioca de Araújo, Bart Kruijt, Etienne Tourigny, Luiz Antônio Cândido, Martin Hodnett, and Javier Tomasella
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2017-203, https://doi.org/10.5194/hess-2017-203, 2017
Revised manuscript not accepted
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This work describes the simulation of surface fluxes in two distinct environments along a topographic gradient in a central Amazonian forest using the INLAND Model. The results show that a surface model can capture the small differences related to energy, water and carbon balance between both sites. These confirms the importance to incorporate subgrid scale variability by including relief attributes of topography, soil and vegetation to better representing Terra Firme forests in these models.
Lore T. Verryckt, Maarten Op de Beeck, Johan Neirynck, Bert Gielen, Marilyn Roland, and Ivan A. Janssens
Biogeosciences, 14, 1839–1855, https://doi.org/10.5194/bg-14-1839-2017, https://doi.org/10.5194/bg-14-1839-2017, 2017
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Ozone (O3) is an air pollutant known to negatively affect vegetation. Typically, high O3 concentrations reduce growth. This study investigated the effect of O3 uptake on the total amount of carbon assimilated by vegetation for a Scots pine stand in Flanders over the period 1998–2013. Although the critical levels for AOT40 and POD1, two indices currently used to estimate O3 damage, were exceeded every year, no O3 effects on daily and growing season GPP were found.
Juan Hong, Mikko Äijälä, Silja A. K. Häme, Liqing Hao, Jonathan Duplissy, Liine M. Heikkinen, Wei Nie, Jyri Mikkilä, Markku Kulmala, Nønne L. Prisle, Annele Virtanen, Mikael Ehn, Pauli Paasonen, Douglas R. Worsnop, Ilona Riipinen, Tuukka Petäjä, and Veli-Matti Kerminen
Atmos. Chem. Phys., 17, 4387–4399, https://doi.org/10.5194/acp-17-4387-2017, https://doi.org/10.5194/acp-17-4387-2017, 2017
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Estimates of volatility of secondary organic aerosols was characterized in a boreal forest environment of Hyytiälä, southern Finland. This was done by interpreting field measurements using a volatility tandem differential mobility analyzer (VTDMA) with a kinetic evaporation model and by applying positive matrix factorization (PMF) to high-resolution aerosol mass spectrometer data. About 16 % of the variation can be explained by the linear regression between the results from these two methods.
Wei Nie, Juan Hong, Silja A. K. Häme, Aijun Ding, Yugen Li, Chao Yan, Liqing Hao, Jyri Mikkilä, Longfei Zheng, Yuning Xie, Caijun Zhu, Zheng Xu, Xuguang Chi, Xin Huang, Yang Zhou, Peng Lin, Annele Virtanen, Douglas R. Worsnop, Markku Kulmala, Mikael Ehn, Jianzhen Yu, Veli-Matti Kerminen, and Tuukka Petäjä
Atmos. Chem. Phys., 17, 3659–3672, https://doi.org/10.5194/acp-17-3659-2017, https://doi.org/10.5194/acp-17-3659-2017, 2017
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HULIS are demonstrated to be important low-volatility, or even extremely low volatility, compounds in the organic aerosol phase. This sheds new light on the connection between atmospheric HULIS and ELVOCs. The interaction between HULIS and ammonium sulfate was found to decrease the volatility of the HULIS part in HULIS-AS mixed samples, indicating multiphase processes have the potential to lower the volatility of organic compounds in the aerosol phase.
Matthieu Guimberteau, Philippe Ciais, Agnès Ducharne, Juan Pablo Boisier, Ana Paula Dutra Aguiar, Hester Biemans, Hannes De Deurwaerder, David Galbraith, Bart Kruijt, Fanny Langerwisch, German Poveda, Anja Rammig, Daniel Andres Rodriguez, Graciela Tejada, Kirsten Thonicke, Celso Von Randow, Rita C. S. Von Randow, Ke Zhang, and Hans Verbeeck
Hydrol. Earth Syst. Sci., 21, 1455–1475, https://doi.org/10.5194/hess-21-1455-2017, https://doi.org/10.5194/hess-21-1455-2017, 2017
Mari Mäki, Jussi Heinonsalo, Heidi Hellén, and Jaana Bäck
Biogeosciences, 14, 1055–1073, https://doi.org/10.5194/bg-14-1055-2017, https://doi.org/10.5194/bg-14-1055-2017, 2017
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The paper demonstrates which different biological factors and physico-chemical processes are important regulators of soil isoprenoid emissions at different times of the year. With the obtained knowledge on soil VOC sources, it will be possible to add soil VOC production into air chemistry models and thus improve the understanding on climatic feedback mechanisms between secondary organic aerosol formation, clouds, and radiative forcing.
Hannele Hakola, Virpi Tarvainen, Arnaud P. Praplan, Kerneels Jaars, Marja Hemmilä, Markku Kulmala, Jaana Bäck, and Heidi Hellén
Atmos. Chem. Phys., 17, 3357–3370, https://doi.org/10.5194/acp-17-3357-2017, https://doi.org/10.5194/acp-17-3357-2017, 2017
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We present spring and summer VOC emission rate measurements from Norway spruce using an in situ gas chromatograph. Monoterpene and C4–C10 aldehyde emission rates reached maxima in July. SQT emissions increased at the end of July and in August SQT were the most abundant group. The MT emission pattern varied a lot from tree to tree and therefore emission fluxes on canopy level should be conducted for more representative measurements. However, leaf level measurements produce more reliable SQT data.
Antti-Jussi Kieloaho, Mari Pihlatie, Samuli Launiainen, Markku Kulmala, Marja-Liisa Riekkola, Jevgeni Parshintsev, Ivan Mammarella, Timo Vesala, and Jussi Heinonsalo
Biogeosciences, 14, 1075–1091, https://doi.org/10.5194/bg-14-1075-2017, https://doi.org/10.5194/bg-14-1075-2017, 2017
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The alkylamines are important precursors in secondary aerosol formation in boreal forests. We quantified alkylamine concentrations in fungal species present in boreal forests in order to estimate soil as a source of atmospheric alkylamines. Based on our knowledge we estimated possible soil–atmosphere exchange of these compounds. The results shows that the boreal forest soil could act as a source of alkylamines depending on environmental conditions and studied compound.
Mikko Äijälä, Liine Heikkinen, Roman Fröhlich, Francesco Canonaco, André S. H. Prévôt, Heikki Junninen, Tuukka Petäjä, Markku Kulmala, Douglas Worsnop, and Mikael Ehn
Atmos. Chem. Phys., 17, 3165–3197, https://doi.org/10.5194/acp-17-3165-2017, https://doi.org/10.5194/acp-17-3165-2017, 2017
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Mass spectrometric measurements commonly yield data on hundreds of variables over thousands of points in time. Refining and synthesising this “raw” data into chemical information necessitates the use of advanced, statistics-based data analysis techniques. Here we present an example of combining data dimensionality reduction (factorisation) with exploratory classification (clustering) and show that the results complement and broaden our current perspectives on aerosol chemical classification.
Carla Frege, Federico Bianchi, Ugo Molteni, Jasmin Tröstl, Heikki Junninen, Stephan Henne, Mikko Sipilä, Erik Herrmann, Michel J. Rossi, Markku Kulmala, Christopher R. Hoyle, Urs Baltensperger, and Josef Dommen
Atmos. Chem. Phys., 17, 2613–2629, https://doi.org/10.5194/acp-17-2613-2017, https://doi.org/10.5194/acp-17-2613-2017, 2017
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We present measurements of the chemical composition of atmospheric ions at high altitude (3450 m a.s.l.) during a 9-month campaign. We detected remarkably high correlation between methanesulfonic acid (MSA) and SO5−. Halogenated species were also detected frequently at this continental location. New-particle formation events occurred via the condensation of highly oxygenated molecules (HOMs) at very low sulfuric acid concentration or, less frequently, due to ammonia–sulfuric acid clusters.
Jenni Kontkanen, Katrianne Lehtipalo, Lauri Ahonen, Juha Kangasluoma, Hanna E. Manninen, Jani Hakala, Clémence Rose, Karine Sellegri, Shan Xiao, Lin Wang, Ximeng Qi, Wei Nie, Aijun Ding, Huan Yu, Shanhu Lee, Veli-Matti Kerminen, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 17, 2163–2187, https://doi.org/10.5194/acp-17-2163-2017, https://doi.org/10.5194/acp-17-2163-2017, 2017
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The concentrations of ~1–3 nm particles were investigated at nine sites around the world. Sub-3 nm particle concentrations were highest at the sites with strong anthropogenic influence. Electrically neutral particles dominated sub-3 nm particle concentrations in polluted environments and in boreal forest during spring and summer. Sub-3 nm particle concentrations were observed to be determined by the availability of precursor vapors rather than the sink caused by preexisting aerosol particles.
Putian Zhou, Laurens Ganzeveld, Üllar Rannik, Luxi Zhou, Rosa Gierens, Ditte Taipale, Ivan Mammarella, and Michael Boy
Atmos. Chem. Phys., 17, 1361–1379, https://doi.org/10.5194/acp-17-1361-2017, https://doi.org/10.5194/acp-17-1361-2017, 2017
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We implemented a multi-layer O3 dry deposition model in a 1-D model SOSAA to simulate O3 flux and concentration within and above a boreal forest at SMEAR II in Hyytiälä, Finland, in August 2010. The results showed that when RH > 70 % the O3 uptake on leaf wet skin was ~ 51 % to the total deposition at night and ~ 19 % at daytime. The sub-canopy contribution below 4.2 m was ~ 38 % at daytime. The averaged daily chemical contribution to total O3 alteration inside the canopy was less than 10 %.
Heidi Hellén, Simon Schallhart, Arnaud P. Praplan, Tuukka Petäjä, and Hannele Hakola
Atmos. Meas. Tech., 10, 281–289, https://doi.org/10.5194/amt-10-281-2017, https://doi.org/10.5194/amt-10-281-2017, 2017
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There is a lack of knowledge of volatile organic acids (VOAs), other than formic and acetic acids in gas phase, and this is at least partly due to the lack of sensitive enough measurement methods. In the present study we developed an in situ GC–MS measurement method for measuring C2–C7 monocarboxylic VOAs at ambient air concentration levels, which we used to measure ambient air concentrations in a boreal forest site. In addition, found mixing ratios were compared with PTR-TOFMS data.
Aino Korrensalo, Pavel Alekseychik, Tomáš Hájek, Janne Rinne, Timo Vesala, Lauri Mehtätalo, Ivan Mammarella, and Eeva-Stiina Tuittila
Biogeosciences, 14, 257–269, https://doi.org/10.5194/bg-14-257-2017, https://doi.org/10.5194/bg-14-257-2017, 2017
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Photosynthetic parameters of peatland plant species were measured over one growing season in an ombrotrophic bog. Based on these measurements, ecosystem-level photosynthesis was calculated for the whole growing season and compared with an estimate derived from micrometeorological measurements. These two estimates corresponded well. Species with low areal cover at the site but high photosynthetic efficiency appeared to be potentially important for the ecosystem-level carbon balance.
Kerneels Jaars, Pieter G. van Zyl, Johan P. Beukes, Heidi Hellén, Ville Vakkari, Micky Josipovic, Andrew D. Venter, Matti Räsänen, Leandra Knoetze, Dirk P. Cilliers, Stefan J. Siebert, Markku Kulmala, Janne Rinne, Alex Guenther, Lauri Laakso, and Hannele Hakola
Atmos. Chem. Phys., 16, 15665–15688, https://doi.org/10.5194/acp-16-15665-2016, https://doi.org/10.5194/acp-16-15665-2016, 2016
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Biogenic volatile organic compounds (BVOCs) – important in tropospheric ozone and secondary organic aerosol formation – were measured at a savannah grassland in South Africa. Results presented are the most extensive for this type of landscape. Compared to other parts of the world, monoterpene levels were similar, while very low isoprene levels led to significantly lower total BVOC levels. BVOC levels were an order of magnitude lower compared to anthropogenic VOC levels measured at Welgegund.
Jing Tang, Guy Schurgers, Hanna Valolahti, Patrick Faubert, Päivi Tiiva, Anders Michelsen, and Riikka Rinnan
Biogeosciences, 13, 6651–6667, https://doi.org/10.5194/bg-13-6651-2016, https://doi.org/10.5194/bg-13-6651-2016, 2016
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Arctic is warming at twice the global average speed and the warming-induced increases in biogenic volatile organic compound (BVOC) emissions from Arctic plants are expected to be drastic. This modelling study aims to investigate BVOC emission responses to warming. The results show that 2 °C summer warming can increase annual emissions by 56 % and the short-term warming responses are strongly impacted by leaf temperature, while the long-time responses are interacted with vegetation changes.
Jarmo Mäkelä, Jouni Susiluoto, Tiina Markkanen, Mika Aurela, Heikki Järvinen, Ivan Mammarella, Stefan Hagemann, and Tuula Aalto
Nonlin. Processes Geophys., 23, 447–465, https://doi.org/10.5194/npg-23-447-2016, https://doi.org/10.5194/npg-23-447-2016, 2016
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The land-based hydrological cycle is one of the key processes controlling the growth and wilting of plants and the amount of carbon vegetation can assimilate. Recent studies have shown that many land surface models have biases in this area. We optimized parameters in one such model (JSBACH) and were able to enhance the model performance in many respects, but the response to drought remained unaffected. Further studies into this aspect should include alternative stomatal conductance formulations.
Bradley O. Christoffersen, Manuel Gloor, Sophie Fauset, Nikolaos M. Fyllas, David R. Galbraith, Timothy R. Baker, Bart Kruijt, Lucy Rowland, Rosie A. Fisher, Oliver J. Binks, Sanna Sevanto, Chonggang Xu, Steven Jansen, Brendan Choat, Maurizio Mencuccini, Nate G. McDowell, and Patrick Meir
Geosci. Model Dev., 9, 4227–4255, https://doi.org/10.5194/gmd-9-4227-2016, https://doi.org/10.5194/gmd-9-4227-2016, 2016
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We developed a plant hydraulics model for tropical forests based on established plant physiological theory, and parameterized it by conducting a pantropical hydraulic trait survey. We show that a substantial amount of trait diversity can be represented in the model by a reduced set of trait dimensions. The fully parameterized model is able capture tree-level variation in water status and improves simulations of total ecosystem transpiration, showing how to incorporate hydraulic traits in models.
Hanna K. Lappalainen, Veli-Matti Kerminen, Tuukka Petäjä, Theo Kurten, Aleksander Baklanov, Anatoly Shvidenko, Jaana Bäck, Timo Vihma, Pavel Alekseychik, Meinrat O. Andreae, Stephen R. Arnold, Mikhail Arshinov, Eija Asmi, Boris Belan, Leonid Bobylev, Sergey Chalov, Yafang Cheng, Natalia Chubarova, Gerrit de Leeuw, Aijun Ding, Sergey Dobrolyubov, Sergei Dubtsov, Egor Dyukarev, Nikolai Elansky, Kostas Eleftheriadis, Igor Esau, Nikolay Filatov, Mikhail Flint, Congbin Fu, Olga Glezer, Aleksander Gliko, Martin Heimann, Albert A. M. Holtslag, Urmas Hõrrak, Juha Janhunen, Sirkku Juhola, Leena Järvi, Heikki Järvinen, Anna Kanukhina, Pavel Konstantinov, Vladimir Kotlyakov, Antti-Jussi Kieloaho, Alexander S. Komarov, Joni Kujansuu, Ilmo Kukkonen, Ella-Maria Duplissy, Ari Laaksonen, Tuomas Laurila, Heikki Lihavainen, Alexander Lisitzin, Alexsander Mahura, Alexander Makshtas, Evgeny Mareev, Stephany Mazon, Dmitry Matishov, Vladimir Melnikov, Eugene Mikhailov, Dmitri Moisseev, Robert Nigmatulin, Steffen M. Noe, Anne Ojala, Mari Pihlatie, Olga Popovicheva, Jukka Pumpanen, Tatjana Regerand, Irina Repina, Aleksei Shcherbinin, Vladimir Shevchenko, Mikko Sipilä, Andrey Skorokhod, Dominick V. Spracklen, Hang Su, Dmitry A. Subetto, Junying Sun, Arkady Y. Terzhevik, Yuri Timofeyev, Yuliya Troitskaya, Veli-Pekka Tynkkynen, Viacheslav I. Kharuk, Nina Zaytseva, Jiahua Zhang, Yrjö Viisanen, Timo Vesala, Pertti Hari, Hans Christen Hansson, Gennady G. Matvienko, Nikolai S. Kasimov, Huadong Guo, Valery Bondur, Sergej Zilitinkevich, and Markku Kulmala
Atmos. Chem. Phys., 16, 14421–14461, https://doi.org/10.5194/acp-16-14421-2016, https://doi.org/10.5194/acp-16-14421-2016, 2016
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After kick off in 2012, the Pan-Eurasian Experiment (PEEX) program has expanded fast and today the multi-disciplinary research community covers ca. 80 institutes and a network of ca. 500 scientists from Europe, Russia, and China. Here we introduce scientific topics relevant in this context. This is one of the first multi-disciplinary overviews crossing scientific boundaries, from atmospheric sciences to socio-economics and social sciences.
Laura Riuttanen, Marja Bister, Veli-Matti Kerminen, Viju O. John, Anu-Maija Sundström, Miikka Dal Maso, Jouni Räisänen, Victoria A. Sinclair, Risto Makkonen, Filippo Xausa, Gerrit de Leeuw, and Markku Kulmala
Atmos. Chem. Phys., 16, 14331–14342, https://doi.org/10.5194/acp-16-14331-2016, https://doi.org/10.5194/acp-16-14331-2016, 2016
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Here we show observational evidence that aerosols increase upper tropospheric humidity (UTH) via changes in the microphysics of deep convection. Using remote sensing data over the ocean east of China in summer, we show that increased aerosol loads are associated with an UTH increase of 2.2 ± 1.5 in units of relative humidity. We show that humidification of aerosols or other meteorological covariation is very unlikely to be the cause for this result indicating relevance for the global climate.
Xuemeng Chen, Veli-Matti Kerminen, Jussi Paatero, Pauli Paasonen, Hanna E. Manninen, Tuomo Nieminen, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 16, 14297–14315, https://doi.org/10.5194/acp-16-14297-2016, https://doi.org/10.5194/acp-16-14297-2016, 2016
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Ionising radiation is responsible for air ion production. However, minor efforts have been invested in understanding the connection of observed air ions to ionising radiation in the lower atmosphere and underlying processes therein. In this work, we analysed 4 years of ambient data collected in a Finnish boreal forest and found that gamma radiation dominates air ion production in the lower atmosphere and demonstrated clear promotion effects of the ionising radiation on air ion production.
Ylva van Meeningen, Guy Schurgers, Riikka Rinnan, and Thomas Holst
Biogeosciences, 13, 6067–6080, https://doi.org/10.5194/bg-13-6067-2016, https://doi.org/10.5194/bg-13-6067-2016, 2016
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English oak and European beech are common European trees known to release volatile compounds such as isoprene and monoterpenes. By doing leaf chamber measurements at three sites in Europe, the aim was to study how the emission differed for cloned trees growing at different sites. The measured emission rates from clones varied between sites, but the relative compound contribution was stable both within and between sites. This can help to increase our knowledge of emission pattern variability.
Michael J. Lawler, Paul M. Winkler, Jaeseok Kim, Lars Ahlm, Jasmin Tröstl, Arnaud P. Praplan, Siegfried Schobesberger, Andreas Kürten, Jasper Kirkby, Federico Bianchi, Jonathan Duplissy, Armin Hansel, Tuija Jokinen, Helmi Keskinen, Katrianne Lehtipalo, Markus Leiminger, Tuukka Petäjä, Matti Rissanen, Linda Rondo, Mario Simon, Mikko Sipilä, Christina Williamson, Daniela Wimmer, Ilona Riipinen, Annele Virtanen, and James N. Smith
Atmos. Chem. Phys., 16, 13601–13618, https://doi.org/10.5194/acp-16-13601-2016, https://doi.org/10.5194/acp-16-13601-2016, 2016
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We present chemical observations of newly formed particles as small as ~ 10 nm from new particle formation experiments using sulfuric acid, dimethylamine, ammonia, and water vapor as gas phase reactants. The nanoparticles were more acidic than expected based on thermodynamic expectations, particularly at the smallest measured sizes. The results suggest rapid surface conversion of SO2 to sulfate and show a marked composition change between 10 and 15 nm, possibly indicating a phase change.
Jenni Kontkanen, Pauli Paasonen, Juho Aalto, Jaana Bäck, Pekka Rantala, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 16, 13291–13307, https://doi.org/10.5194/acp-16-13291-2016, https://doi.org/10.5194/acp-16-13291-2016, 2016
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We developed proxies for estimating the concentrations of monoterpenes and their oxidation products at a boreal forest site in Hyytiälä, Finland. The proxies for the monoterpene concentration include temperature-controlled emissions, dilution and different oxidation processes. The proxies were observed to capture the seasonal and diurnal variation of the monoterpene concentration reasonably well. Our proxies can be used in the analysis of new particle formation and growth in boreal environments.
Üllar Rannik, Olli Peltola, and Ivan Mammarella
Atmos. Meas. Tech., 9, 5163–5181, https://doi.org/10.5194/amt-9-5163-2016, https://doi.org/10.5194/amt-9-5163-2016, 2016
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We review available methods for the random error estimation of turbulent fluxes that are widely used by the flux community. Flux errors are evaluated theoretically as well as via numerical calculations by using measured and simulated records. We recommend two flux random errors with clear physical meaning: the total error resulting from stochastic nature of turbulence, well approximated by the method of Finkelstein and Sims (2001), and the error of the flux due to the instrumental noise.
Kaniska Mallick, Ivonne Trebs, Eva Boegh, Laura Giustarini, Martin Schlerf, Darren T. Drewry, Lucien Hoffmann, Celso von Randow, Bart Kruijt, Alessandro Araùjo, Scott Saleska, James R. Ehleringer, Tomas F. Domingues, Jean Pierre H. B. Ometto, Antonio D. Nobre, Osvaldo Luiz Leal de Moraes, Matthew Hayek, J. William Munger, and Steven C. Wofsy
Hydrol. Earth Syst. Sci., 20, 4237–4264, https://doi.org/10.5194/hess-20-4237-2016, https://doi.org/10.5194/hess-20-4237-2016, 2016
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While quantifying vegetation water use over multiple plant function types in the Amazon Basin, we found substantial biophysical control during drought as well as a water-stress period and dominant climatic control during a water surplus period. This work has direct implication in understanding the resilience of the Amazon forest in the spectre of frequent drought menace as well as the role of drought-induced plant biophysical functioning in modulating the water-carbon coupling in this ecosystem.
Chao Yan, Wei Nie, Mikko Äijälä, Matti P. Rissanen, Manjula R. Canagaratna, Paola Massoli, Heikki Junninen, Tuija Jokinen, Nina Sarnela, Silja A. K. Häme, Siegfried Schobesberger, Francesco Canonaco, Lei Yao, André S. H. Prévôt, Tuukka Petäjä, Markku Kulmala, Mikko Sipilä, Douglas R. Worsnop, and Mikael Ehn
Atmos. Chem. Phys., 16, 12715–12731, https://doi.org/10.5194/acp-16-12715-2016, https://doi.org/10.5194/acp-16-12715-2016, 2016
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Highly oxidized multifunctional compounds (HOMs) are known to have a significant contribution to secondary aerosol formation, yet their dominating formation pathways remain unclear in the atmosphere. We apply positive matrix factorization (PMF) on HOM data, and successfully retrieve factors representing different formation pathways. The results improve our understanding of HOM formation, and provide new perspectives on using PMF to study the variation of short-lived specie.
Marta Camino-Serrano, Elisabeth Graf Pannatier, Sara Vicca, Sebastiaan Luyssaert, Mathieu Jonard, Philippe Ciais, Bertrand Guenet, Bert Gielen, Josep Peñuelas, Jordi Sardans, Peter Waldner, Sophia Etzold, Guia Cecchini, Nicholas Clarke, Zoran Galić, Laure Gandois, Karin Hansen, Jim Johnson, Uwe Klinck, Zora Lachmanová, Antti-Jussi Lindroos, Henning Meesenburg, Tiina M. Nieminen, Tanja G. M. Sanders, Kasia Sawicka, Walter Seidling, Anne Thimonier, Elena Vanguelova, Arne Verstraeten, Lars Vesterdal, and Ivan A. Janssens
Biogeosciences, 13, 5567–5585, https://doi.org/10.5194/bg-13-5567-2016, https://doi.org/10.5194/bg-13-5567-2016, 2016
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We investigated the long-term trends of dissolved organic carbon (DOC) in soil solution and the drivers of changes in over 100 forest monitoring plots across Europe. An overall increasing trend was detected in the organic layers, but no overall trend was found in the mineral horizons. There are strong interactions between controls acting at local and regional scales. Our findings are relevant for researchers focusing on the link between terrestrial and aquatic ecosystems and for C-cycle models.
Ivan Mammarella, Olli Peltola, Annika Nordbo, Leena Järvi, and Üllar Rannik
Atmos. Meas. Tech., 9, 4915–4933, https://doi.org/10.5194/amt-9-4915-2016, https://doi.org/10.5194/amt-9-4915-2016, 2016
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In this study we have performed an inter-comparison between EddyUH and EddyPro, two public and commonly used software packages for eddy covariance data processing and calculation. The aims are to estimate the flux uncertainty due to the use of different software packages, and to assess the most critical processing steps, determining the largest deviations in the calculated fluxes. We focus not only on water vapour and carbon dioxide fluxes, but also on the methane flux.
Mari Pihlatie, Üllar Rannik, Sami Haapanala, Olli Peltola, Narasinha Shurpali, Pertti J. Martikainen, Saara Lind, Niina Hyvönen, Perttu Virkajärvi, Mark Zahniser, and Ivan Mammarella
Biogeosciences, 13, 5471–5485, https://doi.org/10.5194/bg-13-5471-2016, https://doi.org/10.5194/bg-13-5471-2016, 2016
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The sources and sinks of carbon monoxide (CO) in the biosphere are poorly understood. We report the first continuous data series of CO fluxes measured by eddy covariance method in an agricultural bioenergy crop. The CO fluxes were seasonally and diurnally variable demonstrating the parallel consumption and production processes. Radiation was the main driver of CO emissions, and the eddy covariance method was demonstrated as suitable for linking short-term flux dynamics to environmental drivers.
A. M. Yáñez-Serrano, A. C. Nölscher, E. Bourtsoukidis, B. Derstroff, N. Zannoni, V. Gros, M. Lanza, J. Brito, S. M. Noe, E. House, C. N. Hewitt, B. Langford, E. Nemitz, T. Behrendt, J. Williams, P. Artaxo, M. O. Andreae, and J. Kesselmeier
Atmos. Chem. Phys., 16, 10965–10984, https://doi.org/10.5194/acp-16-10965-2016, https://doi.org/10.5194/acp-16-10965-2016, 2016
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This paper provides a general overview of methyl ethyl ketone (MEK) ambient observations in different ecosystems around the world in order to provide insights into the sources, sink and role of MEK in the atmosphere.
Yiying Chen, James Ryder, Vladislav Bastrikov, Matthew J. McGrath, Kim Naudts, Juliane Otto, Catherine Ottlé, Philippe Peylin, Jan Polcher, Aude Valade, Andrew Black, Jan A. Elbers, Eddy Moors, Thomas Foken, Eva van Gorsel, Vanessa Haverd, Bernard Heinesch, Frank Tiedemann, Alexander Knohl, Samuli Launiainen, Denis Loustau, Jérôme Ogée, Timo Vessala, and Sebastiaan Luyssaert
Geosci. Model Dev., 9, 2951–2972, https://doi.org/10.5194/gmd-9-2951-2016, https://doi.org/10.5194/gmd-9-2951-2016, 2016
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In this study, we compiled a set of within-canopy and above-canopy measurements of energy and water fluxes, and used these data to parametrize and validate the new multi-layer energy budget scheme for a range of forest types. An adequate parametrization approach has been presented for the global-scale land surface model (ORCHIDEE-CAN). Furthermore, model performance of the new multi-layer parametrization was compared against the existing single-layer scheme.
Andrey Glazunov, Üllar Rannik, Victor Stepanenko, Vasily Lykosov, Mikko Auvinen, Timo Vesala, and Ivan Mammarella
Geosci. Model Dev., 9, 2925–2949, https://doi.org/10.5194/gmd-9-2925-2016, https://doi.org/10.5194/gmd-9-2925-2016, 2016
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Large-eddy simulation (LES) and Lagrangian stochastic modeling of passive particle dispersion were applied to the scalar flux footprint determination in the stable atmospheric boundary layer. The footprint functions obtained in LES were compared with the functions calculated with the use of first-order single-particle Lagrangian stochastic models (LSMs) and zeroth-order Lagrangian stochastic models - the random displacement models (RDMs).
Luís Miguel Feijó Barreira, Yu Xue, Geoffroy Duporté, Jevgeni Parshintsev, Kari Hartonen, Matti Jussila, Markku Kulmala, and Marja-Liisa Riekkola
Atmos. Meas. Tech., 9, 3661–3671, https://doi.org/10.5194/amt-9-3661-2016, https://doi.org/10.5194/amt-9-3661-2016, 2016
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Volatile organic compounds play a key role in atmospheric chemistry and physics by influencing the climate. Trace concentrations need to be determined, even at remote locations, like forests. In this research, an easy and fast method using a portable device was developed for determination of relevant atmospheric compounds. Links between these compounds and meteorological factors were observed. Also, accumulation of volatiles in the snow was measured.
Hanna E. Manninen, Sander Mirme, Aadu Mirme, Tuukka Petäjä, and Markku Kulmala
Atmos. Meas. Tech., 9, 3577–3605, https://doi.org/10.5194/amt-9-3577-2016, https://doi.org/10.5194/amt-9-3577-2016, 2016
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This paper reports a standard operation procedure (SOP) for a Neutral cluster and Air Ion Spectrometer (NAIS) to detect small clusters and nucleation mode particles. The NAIS measures number size distributions of charged and neutral aerosol particles. The SOP is needed to provide comparable results measured by NAIS users around the world. The work is based on discussions between the NAIS users (lead by University of Helsinki, Finland) and the NAIS manufacturer (Airel Ltd., Estonia).
Minchao Wu, Guy Schurgers, Markku Rummukainen, Benjamin Smith, Patrick Samuelsson, Christer Jansson, Joe Siltberg, and Wilhelm May
Earth Syst. Dynam., 7, 627–647, https://doi.org/10.5194/esd-7-627-2016, https://doi.org/10.5194/esd-7-627-2016, 2016
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On Earth, vegetation does not merely adapt to climate but also imposes significant influences on climate with both local and remote effects. In this study we evaluated the role of vegetation in African climate with a regional Earth system model. By the comparison between the experiments with and without dynamic vegetation changes, we found that vegetation can influence climate remotely, resulting in modulating rainfall patterns over Africa.
Moa K. Sporre, Ewan J. O'Connor, Nina Håkansson, Anke Thoss, Erik Swietlicki, and Tuukka Petäjä
Atmos. Meas. Tech., 9, 3193–3203, https://doi.org/10.5194/amt-9-3193-2016, https://doi.org/10.5194/amt-9-3193-2016, 2016
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Satellite measurements of cloud top height and liquid water path are compared to ground-based remote sensing to evaluate the satellite retrievals. The overall performance of the satellite retrievals of cloud top height are good, but they become more problematic when several layers of clouds are present. The liquid water path retrievals also agree well, and the average differences are within the estimated measurement uncertainties.
Imre Salma, Zoltán Németh, Veli-Matti Kerminen, Pasi Aalto, Tuomo Nieminen, Tamás Weidinger, Ágnes Molnár, Kornélia Imre, and Markku Kulmala
Atmos. Chem. Phys., 16, 8715–8728, https://doi.org/10.5194/acp-16-8715-2016, https://doi.org/10.5194/acp-16-8715-2016, 2016
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We revealed that NPF seen in a central large city of the Carpathian Basin, Budapest, and its regional background occur in a consistent and spatially coherent way as a result of a joint atmospheric phenomenon taking place on large horizontal scales.
Riikka Väänänen, Radovan Krejci, Hanna E. Manninen, Antti Manninen, Janne Lampilahti, Stephany Buenrostro Mazon, Tuomo Nieminen, Taina Yli-Juuti, Jenni Kontkanen, Ari Asmi, Pasi P. Aalto, Petri Keronen, Toivo Pohja, Ewan O'Connor, Veli-Matti Kerminen, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2016-556, https://doi.org/10.5194/acp-2016-556, 2016
Revised manuscript has not been submitted
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A light aircraft was used as a platform to explore the horizontal and vertical variability of the aerosol particles over a boreal forest in Central Finland. This information is needed when data measured at ground level station is extrapolated and parameterized to represent the
conditions of the larger scale. The measurements showed that despite local fluctuations there was a good agreement between the on-ground and airborne measurements inside the planetary boundary layer.
Juha Kangasluoma, Alessandro Franchin, Jonahtan Duplissy, Lauri Ahonen, Frans Korhonen, Michel Attoui, Jyri Mikkilä, Katrianne Lehtipalo, Joonas Vanhanen, Markku Kulmala, and Tuukka Petäjä
Atmos. Meas. Tech., 9, 2977–2988, https://doi.org/10.5194/amt-9-2977-2016, https://doi.org/10.5194/amt-9-2977-2016, 2016
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The paper describes technical aspects of using the Airmodus A11 nCNC at various inlet pressures and how temperature selection affects the performance of the instrument. We also present a sampling box to minimize the inlet losses and make use of the instrument more convenient.
Christian Stiegler, Magnus Lund, Torben Røjle Christensen, Mikhail Mastepanov, and Anders Lindroth
The Cryosphere, 10, 1395–1413, https://doi.org/10.5194/tc-10-1395-2016, https://doi.org/10.5194/tc-10-1395-2016, 2016
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In this study we investigate the impact of strong variability in snow accumulation during 2 subsequent years (2013–2014) on the land–atmosphere interactions and surface energy exchange in two high-Arctic tundra ecosystems (wet fen and dry heath) in Zackenberg, Northeast Greenland. We observe that the energy balance during the snowmelt periods and growing seasons was strongly regulated by the availability of snow meltwater, with strong impact on the overall ecosystem performance.
Pekka Rantala, Leena Järvi, Risto Taipale, Terhi K. Laurila, Johanna Patokoski, Maija K. Kajos, Mona Kurppa, Sami Haapanala, Erkki Siivola, Tuukka Petäjä, Taina M. Ruuskanen, and Janne Rinne
Atmos. Chem. Phys., 16, 7981–8007, https://doi.org/10.5194/acp-16-7981-2016, https://doi.org/10.5194/acp-16-7981-2016, 2016
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Fluxes of volatile organic compounds (VOCs) were measured above an urban landscape in Helsinki, northern Europe. We found that traffic was a major source for many oxygenated and aromatic VOCs, whereas isoprene originated mostly from the urban vegetation. Overall, the VOC fluxes were quite small in comparison with the earlier urban VOC flux measurements.
Alessandro Franchin, Andy Downard, Juha Kangasluoma, Tuomo Nieminen, Katrianne Lehtipalo, Gerhard Steiner, Hanna E. Manninen, Tuukka Petäjä, Richard C. Flagan, and Markku Kulmala
Atmos. Meas. Tech., 9, 2709–2720, https://doi.org/10.5194/amt-9-2709-2016, https://doi.org/10.5194/amt-9-2709-2016, 2016
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High transmission efficiency is key for classifying and counting atmospheric aerosol below 10 nm. We developed a new high-transmission inlet for the Caltech nano-radial DMA (nRDMA) and successfully deployed the nRDMA, equipped with the new inlet, in chamber measurements, using a particle size magnifier (PSM) and a booster CPC as a counter. With this setup, we were able to measure size distributions of ions between 1.3 and 6 nm in mobility diameter.
Johanna Joensuu, Nuria Altimir, Hannele Hakola, Michael Rostás, Maarit Raivonen, Mika Vestenius, Hermanni Aaltonen, Markus Riederer, and Jaana Bäck
Atmos. Chem. Phys., 16, 7813–7823, https://doi.org/10.5194/acp-16-7813-2016, https://doi.org/10.5194/acp-16-7813-2016, 2016
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Plants produce volatile compounds (BVOCs) that have a major role in atmospheric chemistry. Our aim was to see if terpenes, a key group of BVOCs, can be found on surfaces of pine needles and, if so, how they compare with the emissions of the same tree. Both emissions and wax extracts were clearly dominated by monoterpenes, but there were also differences in the emission and wax spectra. The results support the existence of BVOCs on needle surfaces, with possible implications for air chemistry.
Victor Stepanenko, Ivan Mammarella, Anne Ojala, Heli Miettinen, Vasily Lykosov, and Timo Vesala
Geosci. Model Dev., 9, 1977–2006, https://doi.org/10.5194/gmd-9-1977-2016, https://doi.org/10.5194/gmd-9-1977-2016, 2016
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A 1-D lake model is presented, reproducing temperature, oxygen, carbon dioxide and methane. All prognostic variables are treated in unified manner via generic 1-D transport equation. The model is validated vs. comprehensive observational data set gathered at Kuivajärvi Lake (Finland). Our results suggest that a gas transfer through thermocline under intense seiche motions is a bottleneck in quantifying greenhouse gas dynamics in dimictic lakes, calling for further research.
Karoliina Ignatius, Thomas B. Kristensen, Emma Järvinen, Leonid Nichman, Claudia Fuchs, Hamish Gordon, Paul Herenz, Christopher R. Hoyle, Jonathan Duplissy, Sarvesh Garimella, Antonio Dias, Carla Frege, Niko Höppel, Jasmin Tröstl, Robert Wagner, Chao Yan, Antonio Amorim, Urs Baltensperger, Joachim Curtius, Neil M. Donahue, Martin W. Gallagher, Jasper Kirkby, Markku Kulmala, Ottmar Möhler, Harald Saathoff, Martin Schnaiter, Antonio Tomé, Annele Virtanen, Douglas Worsnop, and Frank Stratmann
Atmos. Chem. Phys., 16, 6495–6509, https://doi.org/10.5194/acp-16-6495-2016, https://doi.org/10.5194/acp-16-6495-2016, 2016
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Viscous solid or semi-solid secondary organic aerosol (SOA) may influence cloud properties through ice nucleation in the atmosphere. Here, we observed heterogeneous ice nucleation of viscous α-pinene SOA at temperatures between −39 °C and −37.2 °C with ice saturation ratios significantly below the homogeneous freezing limit. Global modelling suggests that viscous biogenic SOA are present in regions where cirrus formation takes place and could contribute to the global ice nuclei budget.
Jenni Kontkanen, Tinja Olenius, Katrianne Lehtipalo, Hanna Vehkamäki, Markku Kulmala, and Kari E. J. Lehtinen
Atmos. Chem. Phys., 16, 5545–5560, https://doi.org/10.5194/acp-16-5545-2016, https://doi.org/10.5194/acp-16-5545-2016, 2016
Almut Arneth, Risto Makkonen, Stefan Olin, Pauli Paasonen, Thomas Holst, Maija K. Kajos, Markku Kulmala, Trofim Maximov, Paul A. Miller, and Guy Schurgers
Atmos. Chem. Phys., 16, 5243–5262, https://doi.org/10.5194/acp-16-5243-2016, https://doi.org/10.5194/acp-16-5243-2016, 2016
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We study the potentially contrasting effects of enhanced ecosystem CO2 release in response to warmer temperatures vs. emissions of biogenic volatile organic compounds and their formation of secondary organic aerosol through a combination of measurements and modelling at a remote location in Eastern Siberia. The study aims to highlight the number of potentially opposing processes and complex interactions between vegetation physiology, soil processes and trace-gas exchanges in the climate system.
Emma Järvinen, Karoliina Ignatius, Leonid Nichman, Thomas B. Kristensen, Claudia Fuchs, Christopher R. Hoyle, Niko Höppel, Joel C. Corbin, Jill Craven, Jonathan Duplissy, Sebastian Ehrhart, Imad El Haddad, Carla Frege, Hamish Gordon, Tuija Jokinen, Peter Kallinger, Jasper Kirkby, Alexei Kiselev, Karl-Heinz Naumann, Tuukka Petäjä, Tamara Pinterich, Andre S. H. Prevot, Harald Saathoff, Thea Schiebel, Kamalika Sengupta, Mario Simon, Jay G. Slowik, Jasmin Tröstl, Annele Virtanen, Paul Vochezer, Steffen Vogt, Andrea C. Wagner, Robert Wagner, Christina Williamson, Paul M. Winkler, Chao Yan, Urs Baltensperger, Neil M. Donahue, Rick C. Flagan, Martin Gallagher, Armin Hansel, Markku Kulmala, Frank Stratmann, Douglas R. Worsnop, Ottmar Möhler, Thomas Leisner, and Martin Schnaiter
Atmos. Chem. Phys., 16, 4423–4438, https://doi.org/10.5194/acp-16-4423-2016, https://doi.org/10.5194/acp-16-4423-2016, 2016
Üllar Rannik, Luxi Zhou, Putian Zhou, Rosa Gierens, Ivan Mammarella, Andrey Sogachev, and Michael Boy
Atmos. Chem. Phys., 16, 3145–3160, https://doi.org/10.5194/acp-16-3145-2016, https://doi.org/10.5194/acp-16-3145-2016, 2016
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Atmospheric boundary layer (ABL) model coupled with detailed atmospheric chemistry and aerosol dynamical model was used to quantify the role of aerosol and ABL dynamics in the vertical transport of aerosols at a pine forest site in southern Finland. Simulations showed that under dynamical conditions the particle fluxes above canopy can significantly deviate from the dry deposition into the canopy. The deviation can be systematic for certain particle sizes over a period of several days.
Antti J. Manninen, Ewan J. O'Connor, Ville Vakkari, and Tuukka Petäjä
Atmos. Meas. Tech., 9, 817–827, https://doi.org/10.5194/amt-9-817-2016, https://doi.org/10.5194/amt-9-817-2016, 2016
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Current commercially available Doppler lidars provide a cost-effective solution for measuring vertical and horizontal wind velocities, and the co- and cross-polarised backscatter profiles. However, the background noise behaviour becomes a limiting factor for the instrument sensitivity in low aerosol load regions. In this paper we present a correction method which can improve the data availability up to 50 % and greatly improves the calculation of turbulent properties in weak signal regimes.
X. Wu, N. Vuichard, P. Ciais, N. Viovy, N. de Noblet-Ducoudré, X. Wang, V. Magliulo, M. Wattenbach, L. Vitale, P. Di Tommasi, E. J. Moors, W. Jans, J. Elbers, E. Ceschia, T. Tallec, C. Bernhofer, T. Grünwald, C. Moureaux, T. Manise, A. Ligne, P. Cellier, B. Loubet, E. Larmanou, and D. Ripoche
Geosci. Model Dev., 9, 857–873, https://doi.org/10.5194/gmd-9-857-2016, https://doi.org/10.5194/gmd-9-857-2016, 2016
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The response of crops to changing climate and atmospheric CO2 could have large effects on food production, terrestrial carbon, water, energy fluxes and the climate feedbacks. We developed a new process-oriented terrestrial biogeochemical model named ORCHIDEE-CROP (v0), which integrates a generic crop phenology and harvest module into the land surface model ORCHIDEE. Our model has good ability to capture the spatial gradients of crop phenology, carbon and energy-related variables across Europe.
Xin Huang, Luxi Zhou, Aijun Ding, Ximeng Qi, Wei Nie, Minghuai Wang, Xuguang Chi, Tuukka Petäjä, Veli-Matti Kerminen, Pontus Roldin, Anton Rusanen, Markku Kulmala, and Michael Boy
Atmos. Chem. Phys., 16, 2477–2492, https://doi.org/10.5194/acp-16-2477-2016, https://doi.org/10.5194/acp-16-2477-2016, 2016
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By combining a regional model and a box model, this study simulates new particle formation in Nanjing, China, when the air masses were affected by anthropogenic activities, biogenic emissions, or mixed ocean and continental sources. The simulations reveal that biogenic organic compounds play a vital role in growth of newly formed clusters. This novel combination of two models makes it possible to accomplish new particle formation simulation without direct measurements of all chemical species.
Saara E. Lind, Narasinha J. Shurpali, Olli Peltola, Ivan Mammarella, Niina Hyvönen, Marja Maljanen, Mari Räty, Perttu Virkajärvi, and Pertti J. Martikainen
Biogeosciences, 13, 1255–1268, https://doi.org/10.5194/bg-13-1255-2016, https://doi.org/10.5194/bg-13-1255-2016, 2016
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We showed that the reed canary grass (RCG) was environmentally friendly from the CO2 balance point of view when cultivated on this mineral soil. When compared to the earlier findings on the same crop on organic soil site, the capacity of the crop to withdraw atmospheric CO2 was even stronger on the present mineral soil site than that on the organic soil site. For full estimation of the climatic impacts of this bioenergy system, a life cycle assessment will be needed.
M. Dal Maso, L. Liao, J. Wildt, A. Kiendler-Scharr, E. Kleist, R. Tillmann, M. Sipilä, J. Hakala, K. Lehtipalo, M. Ehn, V.-M. Kerminen, M. Kulmala, D. Worsnop, and T. Mentel
Atmos. Chem. Phys., 16, 1955–1970, https://doi.org/10.5194/acp-16-1955-2016, https://doi.org/10.5194/acp-16-1955-2016, 2016
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In this paper, we present the first direct laboratory observations of nanoparticle formation from sulfuric acid and realistic BVOC precursor vapour mixtures performed at atmospherically relevant concentration levels. We found that the formation rate was proportional to the product of sulphuric acid and biogenic VOC emission strength, and that the formation rates were consistent with a mechanism in which nucleating BVOC oxidation products are rapidly formed and activate with sulfuric acid.
Jenni Kontkanen, Emma Järvinen, Hanna E. Manninen, Katrianne Lehtipalo, Juha Kangasluoma, Stefano Decesari, Gian Paolo Gobbi, Ari Laaksonen, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 16, 1919–1935, https://doi.org/10.5194/acp-16-1919-2016, https://doi.org/10.5194/acp-16-1919-2016, 2016
C. R. Hoyle, C. Fuchs, E. Järvinen, H. Saathoff, A. Dias, I. El Haddad, M. Gysel, S. C. Coburn, J. Tröstl, A.-K. Bernhammer, F. Bianchi, M. Breitenlechner, J. C. Corbin, J. Craven, N. M. Donahue, J. Duplissy, S. Ehrhart, C. Frege, H. Gordon, N. Höppel, M. Heinritzi, T. B. Kristensen, U. Molteni, L. Nichman, T. Pinterich, A. S. H. Prévôt, M. Simon, J. G. Slowik, G. Steiner, A. Tomé, A. L. Vogel, R. Volkamer, A. C. Wagner, R. Wagner, A. S. Wexler, C. Williamson, P. M. Winkler, C. Yan, A. Amorim, J. Dommen, J. Curtius, M. W. Gallagher, R. C. Flagan, A. Hansel, J. Kirkby, M. Kulmala, O. Möhler, F. Stratmann, D. R. Worsnop, and U. Baltensperger
Atmos. Chem. Phys., 16, 1693–1712, https://doi.org/10.5194/acp-16-1693-2016, https://doi.org/10.5194/acp-16-1693-2016, 2016
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A significant portion of sulphate, an important constituent of atmospheric aerosols, is formed via the aqueous phase oxidation of sulphur dioxide by ozone. The rate of this reaction has previously only been measured over a relatively small temperature range. Here, we use the state of the art CLOUD chamber at CERN to perform the first measurements of this reaction rate in super-cooled droplets, confirming that the existing extrapolation of the reaction rate to sub-zero temperatures is accurate.
A. Collalti, S. Marconi, A. Ibrom, C. Trotta, A. Anav, E. D'Andrea, G. Matteucci, L. Montagnani, B. Gielen, I. Mammarella, T. Grünwald, A. Knohl, F. Berninger, Y. Zhao, R. Valentini, and M. Santini
Geosci. Model Dev., 9, 479–504, https://doi.org/10.5194/gmd-9-479-2016, https://doi.org/10.5194/gmd-9-479-2016, 2016
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This study evaluates the performances of the new version (v.5.1) of 3D-CMCC Forest Ecosystem Model in simulating gross primary productivity (GPP), against eddy covariance GPP data for 10 FLUXNET forest sites across Europe. The model consistently reproduces both in timing and in magnitude daily and monthly GPP variability across all sites, with the exception of the two Mediterranean sites. Inclusion of forest structure within simulation ameliorate in some cases the model output.
J. Kukkonen, M. Karl, M. P. Keuken, H. A. C. Denier van der Gon, B. R. Denby, V. Singh, J. Douros, A. Manders, Z. Samaras, N. Moussiopoulos, S. Jonkers, M. Aarnio, A. Karppinen, L. Kangas, S. Lützenkirchen, T. Petäjä, I. Vouitsis, and R. S. Sokhi
Geosci. Model Dev., 9, 451–478, https://doi.org/10.5194/gmd-9-451-2016, https://doi.org/10.5194/gmd-9-451-2016, 2016
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For analyzing the health effects of particulate matter, it is necessary to consider not only the mass of particles, but also their sizes and composition. A simple measure for the former is the number concentration of particles. We present particle number concentrations in five major European cities, namely Helsinki, Oslo, London, Rotterdam, and Athens, in 2008, based mainly on modelling. The concentrations of PN were mostly influenced by the emissions from local vehicular traffic.
P. Hari, T. Petäjä, J. Bäck, V.-M. Kerminen, H. K. Lappalainen, T. Vihma, T. Laurila, Y. Viisanen, T. Vesala, and M. Kulmala
Atmos. Chem. Phys., 16, 1017–1028, https://doi.org/10.5194/acp-16-1017-2016, https://doi.org/10.5194/acp-16-1017-2016, 2016
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This manuscript introduces a conceptual design of a global, hierarchical observation network which provides tools and increased understanding to tackle the inter-connected environmental and societal challenges that we will face in the coming decades. Each ecosystem type on the globe has its own characteristic features that need to be taken into consideration. The hierarchical network is able to tackle problems related to large spatial scales, heterogeneity of ecosystems and their complexity.
J. Kim, L. Ahlm, T. Yli-Juuti, M. Lawler, H. Keskinen, J. Tröstl, S. Schobesberger, J. Duplissy, A. Amorim, F. Bianchi, N. M. Donahue, R. C. Flagan, J. Hakala, M. Heinritzi, T. Jokinen, A. Kürten, A. Laaksonen, K. Lehtipalo, P. Miettinen, T. Petäjä, M. P. Rissanen, L. Rondo, K. Sengupta, M. Simon, A. Tomé, C. Williamson, D. Wimmer, P. M. Winkler, S. Ehrhart, P. Ye, J. Kirkby, J. Curtius, U. Baltensperger, M. Kulmala, K. E. J. Lehtinen, J. N. Smith, I. Riipinen, and A. Virtanen
Atmos. Chem. Phys., 16, 293–304, https://doi.org/10.5194/acp-16-293-2016, https://doi.org/10.5194/acp-16-293-2016, 2016
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The hygroscopicity of nucleated nanoparticles was measured in the presence of sulfuric acid, sulfuric acid-dimethylamine, and sulfuric acid-organics derived from α-pinene oxidation during CLOUD7 at CERN in 2012. The hygroscopicity parameter κ decreased with increasing particle size, indicating decreasing acidity of particles.
Y. Gao, T. Markkanen, T. Thum, M. Aurela, A. Lohila, I. Mammarella, M. Kämäräinen, S. Hagemann, and T. Aalto
Hydrol. Earth Syst. Sci., 20, 175–191, https://doi.org/10.5194/hess-20-175-2016, https://doi.org/10.5194/hess-20-175-2016, 2016
R. L. Mauldin III, M. P. Rissanen, T. Petäjä, and M. Kulmala
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2015-398, https://doi.org/10.5194/amt-2015-398, 2016
Revised manuscript not accepted
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The manuscript describes a novel instrument for the measurement of OH, HO2+RO2, and other atmospheric species. The instrument described combines the chemical ionization techniques of nitrate CIMS, OH conversion to H2SO4, HO2+RO2 conversion to H2SO4, and high resolution time of flight mass spectroscopy into one system. By using one instrument to obtain spectra it is possible to compare spectra from the different modes and gain further chemical information towards peak identification.
A. M. K. Hansen, J. Hong, T. Raatikainen, K. Kristensen, A. Ylisirniö, A. Virtanen, T. Petäjä, M. Glasius, and N. L. Prisle
Atmos. Chem. Phys., 15, 14071–14089, https://doi.org/10.5194/acp-15-14071-2015, https://doi.org/10.5194/acp-15-14071-2015, 2015
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This paper presents the first study of the hygroscopic properties of limonene derived organosulfates (L-OS 250). The results showed that L-OS 250 particles are weakly hygroscopic and able to activate into cloud droplets. Particles of L-OS 250 mixed with ammonium sulfate were much more hygroscopic than expected from model parametrizations and the ZSR mixing rule, indicating that solubility and non-ideal droplet interactions could be important for the hygroscopic properties of the mixed particles.
V. N. Dos Santos, E. Herrmann, H. E. Manninen, T. Hussein, J. Hakala, T. Nieminen, P. P. Aalto, M. Merkel, A. Wiedensohler, M. Kulmala, T. Petäjä, and K. Hämeri
Atmos. Chem. Phys., 15, 13717–13737, https://doi.org/10.5194/acp-15-13717-2015, https://doi.org/10.5194/acp-15-13717-2015, 2015
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Atmospheric charged particles, i.e. air ions, contribute to secondary aerosol formation and have an effect on global climate as potential cloud condensation nuclei. We aimed to evaluate air ion concentrations and characteristics during new particle formation (NPF) events in the megacity Paris, France. We analyzed frequency and seasonal variations of NPF events, diurnal and seasonal cycles of ions, and aerosol particles.
S. Olin, M. Lindeskog, T. A. M. Pugh, G. Schurgers, D. Wårlind, M. Mishurov, S. Zaehle, B. D. Stocker, B. Smith, and A. Arneth
Earth Syst. Dynam., 6, 745–768, https://doi.org/10.5194/esd-6-745-2015, https://doi.org/10.5194/esd-6-745-2015, 2015
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Croplands are vital ecosystems for human well-being. Properly managed they can supply food, store carbon and even sequester carbon from the atmosphere. Conversely, if poorly managed, croplands can be a source of nitrogen to inland and coastal waters, causing algal blooms, and a source of carbon dioxide to the atmosphere, accentuating climate change. Here we studied cropland management types for their potential to store carbon and minimize nitrogen losses while maintaining crop yields.
M. Kulmala, H. K. Lappalainen, T. Petäjä, T. Kurten, V.-M. Kerminen, Y. Viisanen, P. Hari, S. Sorvari, J. Bäck, V. Bondur, N. Kasimov, V. Kotlyakov, G. Matvienko, A. Baklanov, H. D. Guo, A. Ding, H.-C. Hansson, and S. Zilitinkevich
Atmos. Chem. Phys., 15, 13085–13096, https://doi.org/10.5194/acp-15-13085-2015, https://doi.org/10.5194/acp-15-13085-2015, 2015
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The Pan-European Experiment (PEEX) is introduced. PEEX is a multidisciplinary, multiscale and multicomponent research, research infrastructure and capacity-building program. This paper outlines the mission, vision and objectives of PEEX and introduces its main components, including the research agenda, research infrastructure, knowledge transfer and potential impacts on society. The paper also summarizes the main scientific questions that PEEX is going to tackle in the future.
C. E. Scott, D. V. Spracklen, J. R. Pierce, I. Riipinen, S. D. D'Andrea, A. Rap, K. S. Carslaw, P. M. Forster, P. Artaxo, M. Kulmala, L. V. Rizzo, E. Swietlicki, G. W. Mann, and K. J. Pringle
Atmos. Chem. Phys., 15, 12989–13001, https://doi.org/10.5194/acp-15-12989-2015, https://doi.org/10.5194/acp-15-12989-2015, 2015
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To understand the radiative effects of biogenic secondary organic aerosol (SOA) it is necessary to consider the manner in which it is distributed across the existing aerosol size distribution. We explore the importance of the approach taken by global-scale models to do this, when calculating the direct radiative effect (DRE) & first aerosol indirect effect (AIE) due to biogenic SOA. This choice has little effect on the DRE, but a substantial impact on the magnitude and even sign of the first AIE
X. M. Qi, A. J. Ding, W. Nie, T. Petäjä, V.-M. Kerminen, E. Herrmann, Y. N. Xie, L. F. Zheng, H. Manninen, P. Aalto, J. N. Sun, Z. N. Xu, X. G. Chi, X. Huang, M. Boy, A. Virkkula, X.-Q. Yang, C. B. Fu, and M. Kulmala
Atmos. Chem. Phys., 15, 12445–12464, https://doi.org/10.5194/acp-15-12445-2015, https://doi.org/10.5194/acp-15-12445-2015, 2015
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We report 2 years of measurements of submicron particles at the SORPES station and provide a comprehensive understanding of main factors controlling temporal variation of the aerosol size distribution and NPF in eastern China. The number concentrations of total particles at Nanjing were comparable to other Chinese megacities but the frequency of NPF was much higher. Year-to-year differences of meteorological conditions could significantly influence the seasonal cycle of NPF and growth.
T. Nieminen, T. Yli-Juuti, H. E. Manninen, T. Petäjä, V.-M. Kerminen, and M. Kulmala
Atmos. Chem. Phys., 15, 12385–12396, https://doi.org/10.5194/acp-15-12385-2015, https://doi.org/10.5194/acp-15-12385-2015, 2015
M. Paramonov, V.-M. Kerminen, M. Gysel, P. P. Aalto, M. O. Andreae, E. Asmi, U. Baltensperger, A. Bougiatioti, D. Brus, G. P. Frank, N. Good, S. S. Gunthe, L. Hao, M. Irwin, A. Jaatinen, Z. Jurányi, S. M. King, A. Kortelainen, A. Kristensson, H. Lihavainen, M. Kulmala, U. Lohmann, S. T. Martin, G. McFiggans, N. Mihalopoulos, A. Nenes, C. D. O'Dowd, J. Ovadnevaite, T. Petäjä, U. Pöschl, G. C. Roberts, D. Rose, B. Svenningsson, E. Swietlicki, E. Weingartner, J. Whitehead, A. Wiedensohler, C. Wittbom, and B. Sierau
Atmos. Chem. Phys., 15, 12211–12229, https://doi.org/10.5194/acp-15-12211-2015, https://doi.org/10.5194/acp-15-12211-2015, 2015
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The research paper presents the first comprehensive overview of field measurements with the CCN Counter performed at a large number of locations around the world within the EUCAARI framework. The paper sheds light on the CCN number concentrations and activated fractions around the world and their dependence on the water vapour supersaturation ratio, the dependence of aerosol hygroscopicity on particle size, and seasonal and diurnal variation of CCN activation and hygroscopic properties.
J. Hong, J. Kim, T. Nieminen, J. Duplissy, M. Ehn, M. Äijälä, L. Q. Hao, W. Nie, N. Sarnela, N. L. Prisle, M. Kulmala, A. Virtanen, T. Petäjä, and V.-M. Kerminen
Atmos. Chem. Phys., 15, 11999–12009, https://doi.org/10.5194/acp-15-11999-2015, https://doi.org/10.5194/acp-15-11999-2015, 2015
M. K. Kajos, P. Rantala, M. Hill, H. Hellén, J. Aalto, J. Patokoski, R. Taipale, C. C. Hoerger, S. Reimann, T. M. Ruuskanen, J. Rinne, and T. Petäjä
Atmos. Meas. Tech., 8, 4453–4473, https://doi.org/10.5194/amt-8-4453-2015, https://doi.org/10.5194/amt-8-4453-2015, 2015
L. Wingate, J. Ogée, E. Cremonese, G. Filippa, T. Mizunuma, M. Migliavacca, C. Moisy, M. Wilkinson, C. Moureaux, G. Wohlfahrt, A. Hammerle, L. Hörtnagl, C. Gimeno, A. Porcar-Castell, M. Galvagno, T. Nakaji, J. Morison, O. Kolle, A. Knohl, W. Kutsch, P. Kolari, E. Nikinmaa, A. Ibrom, B. Gielen, W. Eugster, M. Balzarolo, D. Papale, K. Klumpp, B. Köstner, T. Grünwald, R. Joffre, J.-M. Ourcival, M. Hellstrom, A. Lindroth, C. George, B. Longdoz, B. Genty, J. Levula, B. Heinesch, M. Sprintsin, D. Yakir, T. Manise, D. Guyon, H. Ahrends, A. Plaza-Aguilar, J. H. Guan, and J. Grace
Biogeosciences, 12, 5995–6015, https://doi.org/10.5194/bg-12-5995-2015, https://doi.org/10.5194/bg-12-5995-2015, 2015
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The timing of plant development stages and their response to climate and management were investigated using a network of digital cameras installed across different European ecosystems. Using the relative red, green and blue content of images we showed that the green signal could be used to estimate the length of the growing season in broadleaf forests. We also developed a model that predicted the seasonal variations of camera RGB signals and how they relate to leaf pigment content and area well.
B. Wehner, F. Werner, F. Ditas, R. A. Shaw, M. Kulmala, and H. Siebert
Atmos. Chem. Phys., 15, 11701–11711, https://doi.org/10.5194/acp-15-11701-2015, https://doi.org/10.5194/acp-15-11701-2015, 2015
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During the CARRIBA campaign on Barbados, 91 cases with increased aerosol particle number concentrations near clouds were detected from helicopter-borne measurements. Most of these cases are correlated with enhanced irradiance in the ultraviolet range. The events have a mean length of 100m, corresponding to a lifetime of 300s, meaning a growth of several nm/h. Such high values cannot be explained by sulfuric acid alone; thus extremely low volatility organic compounds are probably involved here.
A. Virkkula, X. Chi, A. Ding, Y. Shen, W. Nie, X. Qi, L. Zheng, X. Huang, Y. Xie, J. Wang, T. Petäjä, and M. Kulmala
Atmos. Meas. Tech., 8, 4415–4427, https://doi.org/10.5194/amt-8-4415-2015, https://doi.org/10.5194/amt-8-4415-2015, 2015
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Aerosol optical properties were measured with a seven-wavelength aethalometer and a three-wavelength nephelometer in Nanjing, China, in September 2013–January 2015. The aethalometer compensation parameter k depended on the backscatter fraction, measured with an independent method, the integrating nephelometer. The compensation parameter decreased with increasing single-scattering albedo.
M. Sipilä, N. Sarnela, T. Jokinen, H. Junninen, J. Hakala, M. P. Rissanen, A. Praplan, M. Simon, A. Kürten, F. Bianchi, J. Dommen, J. Curtius, T. Petäjä, and D. R. Worsnop
Atmos. Meas. Tech., 8, 4001–4011, https://doi.org/10.5194/amt-8-4001-2015, https://doi.org/10.5194/amt-8-4001-2015, 2015
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Atmospheric concentrations of amines are poorly known mainly due to challenges related to their reliable high-sensitivity detection. We have created a method and instrument that is capable for detecting amines with lowest limit of detection of around 0.01 parts per trillion. Application of the instrument in the field study indicates that concentrations of dimethyl amine in a boreal forest site are below 0.03ppt, not enough to account for the observed new particle formation rates.
P. Roldin, L. Liao, D. Mogensen, M. Dal Maso, A. Rusanen, V.-M. Kerminen, T. F. Mentel, J. Wildt, E. Kleist, A. Kiendler-Scharr, R. Tillmann, M. Ehn, M. Kulmala, and M. Boy
Atmos. Chem. Phys., 15, 10777–10798, https://doi.org/10.5194/acp-15-10777-2015, https://doi.org/10.5194/acp-15-10777-2015, 2015
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We used the ADCHAM model to study new particle formation events in the JPAC chamber. The model results show that the new particles may be formed by a kinetic type of nucleation involving both sulphuric acid and organic compounds formed from OH oxidation of volatile organic compounds (VOCs). The observed particle growth may either be controlled by the condensation of semi- and low-volatililty organic compounds or by the formation of low-volatility compounds (oligomers) at the particle surface.
A. Kürten, S. Münch, L. Rondo, F. Bianchi, J. Duplissy, T. Jokinen, H. Junninen, N. Sarnela, S. Schobesberger, M. Simon, M. Sipilä, J. Almeida, A. Amorim, J. Dommen, N. M. Donahue, E. M. Dunne, R. C. Flagan, A. Franchin, J. Kirkby, A. Kupc, V. Makhmutov, T. Petäjä, A. P. Praplan, F. Riccobono, G. Steiner, A. Tomé, G. Tsagkogeorgas, P. E. Wagner, D. Wimmer, U. Baltensperger, M. Kulmala, D. R. Worsnop, and J. Curtius
Atmos. Chem. Phys., 15, 10701–10721, https://doi.org/10.5194/acp-15-10701-2015, https://doi.org/10.5194/acp-15-10701-2015, 2015
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New particle formation (NPF) is an important atmospheric process. At cold temperatures in the upper troposphere the binary (H2SO4-H2O) and ternary (H2SO4-H2O-NH3) system are thought to be important for NPF. Sulfuric acid monomer (H2SO4) and sulfuric acid dimer ((H2SO4)2) concentrations were measured between 208 and 248K for these systems and dimer evaporation rates were derived. These data will help to better understand and predict binary and ternary nucleation at low temperatures.
A. Vanhatalo, T. Chan, J. Aalto, J. F. Korhonen, P. Kolari, T. Hölttä, E. Nikinmaa, and J. Bäck
Biogeosciences, 12, 5353–5363, https://doi.org/10.5194/bg-12-5353-2015, https://doi.org/10.5194/bg-12-5353-2015, 2015
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Boreal coniferous trees emit plenty of volatile monoterpenes into the atmosphere. At our measurement site in Finland, we found a springtime relation between the high monoterpene emission from Scots pine stem and tree water relations. Hence, we suggest that the transient monoterpene burst may be a consequence of the spring recovery of the stem and that the dominant processes and environmental drivers triggering the monoterpene emissions are different between pine stems and foliage.
M. Pikridas, J. Sciare, F. Freutel, S. Crumeyrolle, S.-L. von der Weiden-Reinmüller, A. Borbon, A. Schwarzenboeck, M. Merkel, M. Crippa, E. Kostenidou, M. Psichoudaki, L. Hildebrandt, G. J. Engelhart, T. Petäjä, A. S. H. Prévôt, F. Drewnick, U. Baltensperger, A. Wiedensohler, M. Kulmala, M. Beekmann, and S. N. Pandis
Atmos. Chem. Phys., 15, 10219–10237, https://doi.org/10.5194/acp-15-10219-2015, https://doi.org/10.5194/acp-15-10219-2015, 2015
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Aerosol size distribution measurements from three ground sites, two mobile laboratories, and one airplane are combined to investigate the spatial and temporal variability of ultrafine particles in and around Paris during the summer and winter MEGAPOLI campaigns. The role of nucleation as a particle source and the influence of Paris emissions on their surroundings are examined.
N. Kalivitis, V.-M. Kerminen, G. Kouvarakis, I. Stavroulas, A. Bougiatioti, A. Nenes, H. E. Manninen, T. Petäjä, M. Kulmala, and N. Mihalopoulos
Atmos. Chem. Phys., 15, 9203–9215, https://doi.org/10.5194/acp-15-9203-2015, https://doi.org/10.5194/acp-15-9203-2015, 2015
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Cloud condensation nuclei (CCN) production associated with atmospheric new particle formation (NPF) is presented, and this is the first direct evidence of CCN production resulting from NPF in the eastern Mediterranean atmosphere. We show that condensation of both gaseous sulfuric acid and organic compounds from multiple sources leads to the rapid growth of nucleated particles. Sub-100nm particles were found to be substantially less hygroscopic than larger particles during the active NPF period.
L. Zhou, R. Gierens, A. Sogachev, D. Mogensen, J. Ortega, J. N. Smith, P. C. Harley, A. J. Prenni, E. J. T. Levin, A. Turnipseed, A. Rusanen, S. Smolander, A. B. Guenther, M. Kulmala, T. Karl, and M. Boy
Atmos. Chem. Phys., 15, 8643–8656, https://doi.org/10.5194/acp-15-8643-2015, https://doi.org/10.5194/acp-15-8643-2015, 2015
M. H. Vermeulen, B. J. Kruijt, T. Hickler, and P. Kabat
Earth Syst. Dynam., 6, 485–503, https://doi.org/10.5194/esd-6-485-2015, https://doi.org/10.5194/esd-6-485-2015, 2015
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We compared a process-based ecosystem model (LPJ-GUESS) with EC measurements to test whether observed interannual variability (IAV) in carbon and water fluxes can be reproduced because it is important to understand the driving mechanisms of IAV. We show that the model's mechanistic process representation for photosynthesis at low temperatures and during drought could be improved, but other process representations are still lacking in order to fully reproduce the observed IAV.
S. Dengel, J. Grace, and A. MacArthur
Biogeosciences, 12, 4195–4207, https://doi.org/10.5194/bg-12-4195-2015, https://doi.org/10.5194/bg-12-4195-2015, 2015
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We tested the hypothesis that diffuse radiation from cloudy and overcast skies penetrates the canopy more effectively than direct radiation from clear skies. We compared the flux density and spectral properties of direct and diffuse radiation above, within and below a forest stand under sunny, cloudy and overcast conditions in a thinned Sitka spruce forest. We recorded vertical (1m resolution) and horizontal (2.5m resolution) profiles of radiation penetration at 1nm resolution.
D. Wimmer, K. Lehtipalo, T. Nieminen, J. Duplissy, S. Ehrhart, J. Almeida, L. Rondo, A. Franchin, F. Kreissl, F. Bianchi, H. E. Manninen, M. Kulmala, J. Curtius, and T. Petäjä
Atmos. Chem. Phys., 15, 7547–7555, https://doi.org/10.5194/acp-15-7547-2015, https://doi.org/10.5194/acp-15-7547-2015, 2015
P. Zieger, P. P. Aalto, V. Aaltonen, M. Äijälä, J. Backman, J. Hong, M. Komppula, R. Krejci, M. Laborde, J. Lampilahti, G. de Leeuw, A. Pfüller, B. Rosati, M. Tesche, P. Tunved, R. Väänänen, and T. Petäjä
Atmos. Chem. Phys., 15, 7247–7267, https://doi.org/10.5194/acp-15-7247-2015, https://doi.org/10.5194/acp-15-7247-2015, 2015
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The effect of water uptake (hygroscopicity) on aerosol light scattering properties is generally lower for boreal aerosol due to the dominance of organic substances. A columnar optical closure study using ground-based and airborne measurements of aerosol optical, chemical and microphysical properties was conducted and the implications and limitations are discussed.
F. Minunno, M. Peltoniemi, S. Launiainen, M. Aurela, A. Lindroth, A. Lohila, I. Mammarella, K. Minkkinen, and A. Mäkelä
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmdd-8-5089-2015, https://doi.org/10.5194/gmdd-8-5089-2015, 2015
Revised manuscript not accepted
A. Franchin, S. Ehrhart, J. Leppä, T. Nieminen, S. Gagné, S. Schobesberger, D. Wimmer, J. Duplissy, F. Riccobono, E. M. Dunne, L. Rondo, A. Downard, F. Bianchi, A. Kupc, G. Tsagkogeorgas, K. Lehtipalo, H. E. Manninen, J. Almeida, A. Amorim, P. E. Wagner, A. Hansel, J. Kirkby, A. Kürten, N. M. Donahue, V. Makhmutov, S. Mathot, A. Metzger, T. Petäjä, R. Schnitzhofer, M. Sipilä, Y. Stozhkov, A. Tomé, V.-M. Kerminen, K. Carslaw, J. Curtius, U. Baltensperger, and M. Kulmala
Atmos. Chem. Phys., 15, 7203–7216, https://doi.org/10.5194/acp-15-7203-2015, https://doi.org/10.5194/acp-15-7203-2015, 2015
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The ion-ion recombination coefficient was measured at different temperatures, relative humidities and concentrations of ozone and sulfur dioxide. The experiments were carried out using the CLOUD chamber at CERN.
We observed a strong dependency on temperature and on relative humidity, which has not been reported previously. No dependency of the ion-ion recombination coefficient on ozone concentration was observed and a weak variation with sulfur dioxide concentration was also observed.
J.-P. Pietikäinen, K. Kupiainen, Z. Klimont, R. Makkonen, H. Korhonen, R. Karinkanta, A.-P. Hyvärinen, N. Karvosenoja, A. Laaksonen, H. Lihavainen, and V.-M. Kerminen
Atmos. Chem. Phys., 15, 5501–5519, https://doi.org/10.5194/acp-15-5501-2015, https://doi.org/10.5194/acp-15-5501-2015, 2015
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The global aerosol--climate model ECHAM-HAMMOZ is used to study the aerosol burden and forcing changes in the coming decades. We show that aerosol burdens overall can have a decreasing trend leading to reductions in the direct aerosol effect being globally 0.06--0.4W/m2 by 2030, whereas the aerosol indirect radiative effect could decline 0.25--0.82W/m2. We also show that the targeted emission reduction measures can be a much better choice for the climate than overall high reductions globally.
N. Sudarchikova, U. Mikolajewicz, C. Timmreck, D. O'Donnell, G. Schurgers, D. Sein, and K. Zhang
Clim. Past, 11, 765–779, https://doi.org/10.5194/cp-11-765-2015, https://doi.org/10.5194/cp-11-765-2015, 2015
A.-M. Sundström, A. Nikandrova, K. Atlaskina, T. Nieminen, V. Vakkari, L. Laakso, J. P. Beukes, A. Arola, P. G. van Zyl, M. Josipovic, A. D. Venter, K. Jaars, J. J. Pienaar, S. Piketh, A. Wiedensohler, E. K. Chiloane, G. de Leeuw, and M. Kulmala
Atmos. Chem. Phys., 15, 4983–4996, https://doi.org/10.5194/acp-15-4983-2015, https://doi.org/10.5194/acp-15-4983-2015, 2015
S. Olin, G. Schurgers, M. Lindeskog, D. Wårlind, B. Smith, P. Bodin, J. Holmér, and A. Arneth
Biogeosciences, 12, 2489–2515, https://doi.org/10.5194/bg-12-2489-2015, https://doi.org/10.5194/bg-12-2489-2015, 2015
A. P. Praplan, S. Schobesberger, F. Bianchi, M. P. Rissanen, M. Ehn, T. Jokinen, H. Junninen, A. Adamov, A. Amorim, J. Dommen, J. Duplissy, J. Hakala, A. Hansel, M. Heinritzi, J. Kangasluoma, J. Kirkby, M. Krapf, A. Kürten, K. Lehtipalo, F. Riccobono, L. Rondo, N. Sarnela, M. Simon, A. Tomé, J. Tröstl, P. M. Winkler, C. Williamson, P. Ye, J. Curtius, U. Baltensperger, N. M. Donahue, M. Kulmala, and D. R. Worsnop
Atmos. Chem. Phys., 15, 4145–4159, https://doi.org/10.5194/acp-15-4145-2015, https://doi.org/10.5194/acp-15-4145-2015, 2015
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Our study shows, based on data from three atmospheric pressure interface time-of-flight mass spectrometers measuring in parallel charged and neutral molecules and molecular clusters, how oxidised organic compounds bind to inorganic ions (e.g. bisulfate, nitrate, ammonium). This ionisation is selective for compounds with lower molar mass due to their limited amount and variety of functional groups. We also found that extremely low volatile organic compounds (ELVOCs) can be formed immediately.
D. Mogensen, R. Gierens, J. N. Crowley, P. Keronen, S. Smolander, A. Sogachev, A. C. Nölscher, L. Zhou, M. Kulmala, M. J. Tang, J. Williams, and M. Boy
Atmos. Chem. Phys., 15, 3909–3932, https://doi.org/10.5194/acp-15-3909-2015, https://doi.org/10.5194/acp-15-3909-2015, 2015
K. Neitola, D. Brus, U. Makkonen, M. Sipilä, R. L. Mauldin III, N. Sarnela, T. Jokinen, H. Lihavainen, and M. Kulmala
Atmos. Chem. Phys., 15, 3429–3443, https://doi.org/10.5194/acp-15-3429-2015, https://doi.org/10.5194/acp-15-3429-2015, 2015
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A discrepancy of 2 orders of magnitude was found between the measured sulfuric acid monomer concentration and total sulfate, when measured with independent methods (mass spectrometry and ion chromatography) with the same source of sulphuric acid vapor. The ion chromatography method produces the exact concentrations predicted by empirical equations, and the mass spectrometry method shows significantly lower values. The discrepancy is investigated thoroughly from different points of views.
C. Rose, K. Sellegri, E. Asmi, M. Hervo, E. Freney, A. Colomb, H. Junninen, J. Duplissy, M. Sipilä, J. Kontkanen, K. Lehtipalo, and M. Kulmala
Atmos. Chem. Phys., 15, 3413–3428, https://doi.org/10.5194/acp-15-3413-2015, https://doi.org/10.5194/acp-15-3413-2015, 2015
S. Xiao, M. Y. Wang, L. Yao, M. Kulmala, B. Zhou, X. Yang, J. M. Chen, D. F. Wang, Q. Y. Fu, D. R. Worsnop, and L. Wang
Atmos. Chem. Phys., 15, 1769–1781, https://doi.org/10.5194/acp-15-1769-2015, https://doi.org/10.5194/acp-15-1769-2015, 2015
W. Nie, A. J. Ding, Y. N. Xie, Z. Xu, H. Mao, V.-M. Kerminen, L. F. Zheng, X. M. Qi, X. Huang, X.-Q. Yang, J. N. Sun, E. Herrmann, T. Petäjä, M. Kulmala, and C. B. Fu
Atmos. Chem. Phys., 15, 1147–1159, https://doi.org/10.5194/acp-15-1147-2015, https://doi.org/10.5194/acp-15-1147-2015, 2015
H. Vuollekoski, M. Vogt, V. A. Sinclair, J. Duplissy, H. Järvinen, E.-M. Kyrö, R. Makkonen, T. Petäjä, N. L. Prisle, P. Räisänen, M. Sipilä, J. Ylhäisi, and M. Kulmala
Hydrol. Earth Syst. Sci., 19, 601–613, https://doi.org/10.5194/hess-19-601-2015, https://doi.org/10.5194/hess-19-601-2015, 2015
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The global potential for collecting usable water from dew on an
artificial collector sheet was investigated by utilising 34 years of
meteorological reanalysis data as input to a dew formation model. Continental dew formation was found to be frequent and common, but daily yields were
mostly below 0.1mm.
R. Oswald, M. Ermel, K. Hens, A. Novelli, H. G. Ouwersloot, P. Paasonen, T. Petäjä, M. Sipilä, P. Keronen, J. Bäck, R. Königstedt, Z. Hosaynali Beygi, H. Fischer, B. Bohn, D. Kubistin, H. Harder, M. Martinez, J. Williams, T. Hoffmann, I. Trebs, and M. Sörgel
Atmos. Chem. Phys., 15, 799–813, https://doi.org/10.5194/acp-15-799-2015, https://doi.org/10.5194/acp-15-799-2015, 2015
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Nitrous acid (HONO) is a key species in atmospheric photochemistry since the photolysis leads to the important hydroxyl radical (OH). Although the importance of HONO as a precursor of OH is known, the formation pathways of HONO, especially during daytime, are a major challenge in atmospheric science. We present a detailed analysis of sources and sinks for HONO in the atmosphere for a field measurement campaign in the boreal forest in Finland and wonder if there is really a source term missing.
Ü. Rannik, S. Haapanala, N. J. Shurpali, I. Mammarella, S. Lind, N. Hyvönen, O. Peltola, M. Zahniser, P. J. Martikainen, and T. Vesala
Biogeosciences, 12, 415–432, https://doi.org/10.5194/bg-12-415-2015, https://doi.org/10.5194/bg-12-415-2015, 2015
A.-M. Sundström, A. Arola, P. Kolmonen, Y. Xue, G. de Leeuw, and M. Kulmala
Atmos. Chem. Phys., 15, 505–518, https://doi.org/10.5194/acp-15-505-2015, https://doi.org/10.5194/acp-15-505-2015, 2015
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In this work, a satellite-based approach to derive the aerosol direct shortwave (SW) radiative effect (ADRE) is studied. The method is based on using coincident satellite observations of SW fluxes and aerosol optical depths (AODs). The key findings of this study are that using normalized values of observed fluxes improves the estimates of ADRE and aerosol-free TOA fluxes as compared to a model. The method was applied over eastern China where the satellite-based mean ADRE of -5Wm-2 was obtained.
G. Schurgers, F. Lagergren, M. Mölder, and A. Lindroth
Biogeosciences, 12, 237–256, https://doi.org/10.5194/bg-12-237-2015, https://doi.org/10.5194/bg-12-237-2015, 2015
S. Schobesberger, A. Franchin, F. Bianchi, L. Rondo, J. Duplissy, A. Kürten, I. K. Ortega, A. Metzger, R. Schnitzhofer, J. Almeida, A. Amorim, J. Dommen, E. M. Dunne, M. Ehn, S. Gagné, L. Ickes, H. Junninen, A. Hansel, V.-M. Kerminen, J. Kirkby, A. Kupc, A. Laaksonen, K. Lehtipalo, S. Mathot, A. Onnela, T. Petäjä, F. Riccobono, F. D. Santos, M. Sipilä, A. Tomé, G. Tsagkogeorgas, Y. Viisanen, P. E. Wagner, D. Wimmer, J. Curtius, N. M. Donahue, U. Baltensperger, M. Kulmala, and D. R. Worsnop
Atmos. Chem. Phys., 15, 55–78, https://doi.org/10.5194/acp-15-55-2015, https://doi.org/10.5194/acp-15-55-2015, 2015
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We used an ion mass spectrometer at CERN's CLOUD chamber to investigate the detailed composition of ammonia--sulfuric acid ion clusters (of both polarities) as they initially form and then grow into aerosol particles, at atmospherically relevant conditions. We found that these clusters’ composition is mainly determined by the ratio of the precursor vapors and ranges from ammonia-free clusters to clusters containing > 1 ammonia per sulfuric acid. Acid--base bindings are a key formation mechanism.
J. Backman, A. Virkkula, V. Vakkari, J. P. Beukes, P. G. Van Zyl, M. Josipovic, S. Piketh, P. Tiitta, K. Chiloane, T. Petäjä, M. Kulmala, and L. Laakso
Atmos. Meas. Tech., 7, 4285–4298, https://doi.org/10.5194/amt-7-4285-2014, https://doi.org/10.5194/amt-7-4285-2014, 2014
M. Sipilä, T. Jokinen, T. Berndt, S. Richters, R. Makkonen, N. M. Donahue, R. L. Mauldin III, T. Kurtén, P. Paasonen, N. Sarnela, M. Ehn, H. Junninen, M. P. Rissanen, J. Thornton, F. Stratmann, H. Herrmann, D. R. Worsnop, M. Kulmala, V.-M. Kerminen, and T. Petäjä
Atmos. Chem. Phys., 14, 12143–12153, https://doi.org/10.5194/acp-14-12143-2014, https://doi.org/10.5194/acp-14-12143-2014, 2014
M. K. Sporre, E. Swietlicki, P. Glantz, and M. Kulmala
Atmos. Chem. Phys., 14, 12167–12179, https://doi.org/10.5194/acp-14-12167-2014, https://doi.org/10.5194/acp-14-12167-2014, 2014
L. Rondo, A. Kürten, S. Ehrhart, S. Schobesberger, A. Franchin, H. Junninen, T. Petäjä, M. Sipilä, D. R. Worsnop, and J. Curtius
Atmos. Meas. Tech., 7, 3849–3859, https://doi.org/10.5194/amt-7-3849-2014, https://doi.org/10.5194/amt-7-3849-2014, 2014
J. Kukkonen, J. Nikmo, M. Sofiev, K. Riikonen, T. Petäjä, A. Virkkula, J. Levula, S. Schobesberger, and D. M. Webber
Geosci. Model Dev., 7, 2663–2681, https://doi.org/10.5194/gmd-7-2663-2014, https://doi.org/10.5194/gmd-7-2663-2014, 2014
E. Sundqvist, P. Vestin, P. Crill, T. Persson, and A. Lindroth
Biogeosciences, 11, 6095–6105, https://doi.org/10.5194/bg-11-6095-2014, https://doi.org/10.5194/bg-11-6095-2014, 2014
J.-P. Pietikäinen, S. Mikkonen, A. Hamed, A. I. Hienola, W. Birmili, M. Kulmala, and A. Laaksonen
Atmos. Chem. Phys., 14, 11711–11729, https://doi.org/10.5194/acp-14-11711-2014, https://doi.org/10.5194/acp-14-11711-2014, 2014
S. G. Gonser, F. Klein, W. Birmili, J. Größ, M. Kulmala, H. E. Manninen, A. Wiedensohler, and A. Held
Atmos. Chem. Phys., 14, 10547–10563, https://doi.org/10.5194/acp-14-10547-2014, https://doi.org/10.5194/acp-14-10547-2014, 2014
S. Smolander, Q. He, D. Mogensen, L. Zhou, J. Bäck, T. Ruuskanen, S. Noe, A. Guenther, H. Aaltonen, M. Kulmala, and M. Boy
Biogeosciences, 11, 5425–5443, https://doi.org/10.5194/bg-11-5425-2014, https://doi.org/10.5194/bg-11-5425-2014, 2014
K. Hens, A. Novelli, M. Martinez, J. Auld, R. Axinte, B. Bohn, H. Fischer, P. Keronen, D. Kubistin, A. C. Nölscher, R. Oswald, P. Paasonen, T. Petäjä, E. Regelin, R. Sander, V. Sinha, M. Sipilä, D. Taraborrelli, C. Tatum Ernest, J. Williams, J. Lelieveld, and H. Harder
Atmos. Chem. Phys., 14, 8723–8747, https://doi.org/10.5194/acp-14-8723-2014, https://doi.org/10.5194/acp-14-8723-2014, 2014
L. Liao, V.-M. Kerminen, M. Boy, M. Kulmala, and M. Dal Maso
Atmos. Chem. Phys., 14, 8295–8308, https://doi.org/10.5194/acp-14-8295-2014, https://doi.org/10.5194/acp-14-8295-2014, 2014
E. Podgrajsek, E. Sahlée, D. Bastviken, J. Holst, A. Lindroth, L. Tranvik, and A. Rutgersson
Biogeosciences, 11, 4225–4233, https://doi.org/10.5194/bg-11-4225-2014, https://doi.org/10.5194/bg-11-4225-2014, 2014
M. Vestenius, H. Hellén, J. Levula, P. Kuronen, K.J. Helminen, T. Nieminen, M. Kulmala, and H. Hakola
Atmos. Chem. Phys., 14, 7883–7893, https://doi.org/10.5194/acp-14-7883-2014, https://doi.org/10.5194/acp-14-7883-2014, 2014
A. Arneth, S. Olin, R. Makkonen, P. Paasonen, T. Holst, M. Kajos, M. Kulmala, T. Maximov, P. A. Miller, and G. Schurgers
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-14-19149-2014, https://doi.org/10.5194/acpd-14-19149-2014, 2014
Revised manuscript not accepted
K. Jaars, J. P. Beukes, P. G. van Zyl, A. D. Venter, M. Josipovic, J. J. Pienaar, V. Vakkari, H. Aaltonen, H. Laakso, M. Kulmala, P. Tiitta, A. Guenther, H. Hellén, L. Laakso, and H. Hakola
Atmos. Chem. Phys., 14, 7075–7089, https://doi.org/10.5194/acp-14-7075-2014, https://doi.org/10.5194/acp-14-7075-2014, 2014
M. Crippa, F. Canonaco, V. A. Lanz, M. Äijälä, J. D. Allan, S. Carbone, G. Capes, D. Ceburnis, M. Dall'Osto, D. A. Day, P. F. DeCarlo, M. Ehn, A. Eriksson, E. Freney, L. Hildebrandt Ruiz, R. Hillamo, J. L. Jimenez, H. Junninen, A. Kiendler-Scharr, A.-M. Kortelainen, M. Kulmala, A. Laaksonen, A. A. Mensah, C. Mohr, E. Nemitz, C. O'Dowd, J. Ovadnevaite, S. N. Pandis, T. Petäjä, L. Poulain, S. Saarikoski, K. Sellegri, E. Swietlicki, P. Tiitta, D. R. Worsnop, U. Baltensperger, and A. S. H. Prévôt
Atmos. Chem. Phys., 14, 6159–6176, https://doi.org/10.5194/acp-14-6159-2014, https://doi.org/10.5194/acp-14-6159-2014, 2014
O. Peltola, A. Hensen, C. Helfter, L. Belelli Marchesini, F. C. Bosveld, W. C. M. van den Bulk, J. A. Elbers, S. Haapanala, J. Holst, T. Laurila, A. Lindroth, E. Nemitz, T. Röckmann, A. T. Vermeulen, and I. Mammarella
Biogeosciences, 11, 3163–3186, https://doi.org/10.5194/bg-11-3163-2014, https://doi.org/10.5194/bg-11-3163-2014, 2014
A. Hirsikko, E. J. O'Connor, M. Komppula, K. Korhonen, A. Pfüller, E. Giannakaki, C. R. Wood, M. Bauer-Pfundstein, A. Poikonen, T. Karppinen, H. Lonka, M. Kurri, J. Heinonen, D. Moisseev, E. Asmi, V. Aaltonen, A. Nordbo, E. Rodriguez, H. Lihavainen, A. Laaksonen, K. E. J. Lehtinen, T. Laurila, T. Petäjä, M. Kulmala, and Y. Viisanen
Atmos. Meas. Tech., 7, 1351–1375, https://doi.org/10.5194/amt-7-1351-2014, https://doi.org/10.5194/amt-7-1351-2014, 2014
G. W. Mann, K. S. Carslaw, C. L. Reddington, K. J. Pringle, M. Schulz, A. Asmi, D. V. Spracklen, D. A. Ridley, M. T. Woodhouse, L. A. Lee, K. Zhang, S. J. Ghan, R. C. Easter, X. Liu, P. Stier, Y. H. Lee, P. J. Adams, H. Tost, J. Lelieveld, S. E. Bauer, K. Tsigaridis, T. P. C. van Noije, A. Strunk, E. Vignati, N. Bellouin, M. Dalvi, C. E. Johnson, T. Bergman, H. Kokkola, K. von Salzen, F. Yu, G. Luo, A. Petzold, J. Heintzenberg, A. Clarke, J. A. Ogren, J. Gras, U. Baltensperger, U. Kaminski, S. G. Jennings, C. D. O'Dowd, R. M. Harrison, D. C. S. Beddows, M. Kulmala, Y. Viisanen, V. Ulevicius, N. Mihalopoulos, V. Zdimal, M. Fiebig, H.-C. Hansson, E. Swietlicki, and J. S. Henzing
Atmos. Chem. Phys., 14, 4679–4713, https://doi.org/10.5194/acp-14-4679-2014, https://doi.org/10.5194/acp-14-4679-2014, 2014
J. Hong, S. A. K. Häkkinen, M. Paramonov, M. Äijälä, J. Hakala, T. Nieminen, J. Mikkilä, N. L. Prisle, M. Kulmala, I. Riipinen, M. Bilde, V.-M. Kerminen, and T. Petäjä
Atmos. Chem. Phys., 14, 4733–4748, https://doi.org/10.5194/acp-14-4733-2014, https://doi.org/10.5194/acp-14-4733-2014, 2014
A. Virkkula, J. Levula, T. Pohja, P. P. Aalto, P. Keronen, S. Schobesberger, C. B. Clements, L. Pirjola, A.-J. Kieloaho, L. Kulmala, H. Aaltonen, J. Patokoski, J. Pumpanen, J. Rinne, T. Ruuskanen, M. Pihlatie, H. E. Manninen, V. Aaltonen, H. Junninen, T. Petäjä, J. Backman, M. Dal Maso, T. Nieminen, T. Olsson, T. Grönholm, J. Aalto, T. H. Virtanen, M. Kajos, V.-M. Kerminen, D. M. Schultz, J. Kukkonen, M. Sofiev, G. De Leeuw, J. Bäck, P. Hari, and M. Kulmala
Atmos. Chem. Phys., 14, 4473–4502, https://doi.org/10.5194/acp-14-4473-2014, https://doi.org/10.5194/acp-14-4473-2014, 2014
E.-M. Kyrö, R. Väänänen, V.-M. Kerminen, A. Virkkula, T. Petäjä, A. Asmi, M. Dal Maso, T. Nieminen, S. Juhola, A. Shcherbinin, I. Riipinen, K. Lehtipalo, P. Keronen, P. P. Aalto, P. Hari, and M. Kulmala
Atmos. Chem. Phys., 14, 4383–4396, https://doi.org/10.5194/acp-14-4383-2014, https://doi.org/10.5194/acp-14-4383-2014, 2014
D. C. S. Beddows, M. Dall'Osto, R. M. Harrison, M. Kulmala, A. Asmi, A. Wiedensohler, P. Laj, A.M. Fjaeraa, K. Sellegri, W. Birmili, N. Bukowiecki, E. Weingartner, U. Baltensperger, V. Zdimal, N. Zikova, J.-P. Putaud, A. Marinoni, P. Tunved, H.-C. Hansson, M. Fiebig, N. Kivekäs, E. Swietlicki, H. Lihavainen, E. Asmi, V. Ulevicius, P. P. Aalto, N. Mihalopoulos, N. Kalivitis, I. Kalapov, G. Kiss, G. de Leeuw, B. Henzing, C. O'Dowd, S. G. Jennings, H. Flentje, F. Meinhardt, L. Ries, H. A. C. Denier van der Gon, and A. J. H. Visschedijk
Atmos. Chem. Phys., 14, 4327–4348, https://doi.org/10.5194/acp-14-4327-2014, https://doi.org/10.5194/acp-14-4327-2014, 2014
J. Aalto, P. Kolari, P. Hari, V.-M. Kerminen, P. Schiestl-Aalto, H. Aaltonen, J. Levula, E. Siivola, M. Kulmala, and J. Bäck
Biogeosciences, 11, 1331–1344, https://doi.org/10.5194/bg-11-1331-2014, https://doi.org/10.5194/bg-11-1331-2014, 2014
J. Kangasluoma, C. Kuang, D. Wimmer, M. P. Rissanen, K. Lehtipalo, M. Ehn, D. R. Worsnop, J. Wang, M. Kulmala, and T. Petäjä
Atmos. Meas. Tech., 7, 689–700, https://doi.org/10.5194/amt-7-689-2014, https://doi.org/10.5194/amt-7-689-2014, 2014
E. Herrmann, A. J. Ding, V.-M. Kerminen, T. Petäjä, X. Q. Yang, J. N. Sun, X. M. Qi, H. Manninen, J. Hakala, T. Nieminen, P. P. Aalto, M. Kulmala, and C. B. Fu
Atmos. Chem. Phys., 14, 2169–2183, https://doi.org/10.5194/acp-14-2169-2014, https://doi.org/10.5194/acp-14-2169-2014, 2014
I. Kourtchev, S. J. Fuller, C. Giorio, R. M. Healy, E. Wilson, I. O'Connor, J. C. Wenger, M. McLeod, J. Aalto, T. M. Ruuskanen, W. Maenhaut, R. Jones, D. S. Venables, J. R. Sodeau, M. Kulmala, and M. Kalberer
Atmos. Chem. Phys., 14, 2155–2167, https://doi.org/10.5194/acp-14-2155-2014, https://doi.org/10.5194/acp-14-2155-2014, 2014
P. Tiitta, V. Vakkari, P. Croteau, J. P. Beukes, P. G. van Zyl, M. Josipovic, A. D. Venter, K. Jaars, J. J. Pienaar, N. L. Ng, M. R. Canagaratna, J. T. Jayne, V.-M. Kerminen, H. Kokkola, M. Kulmala, A. Laaksonen, D. R. Worsnop, and L. Laakso
Atmos. Chem. Phys., 14, 1909–1927, https://doi.org/10.5194/acp-14-1909-2014, https://doi.org/10.5194/acp-14-1909-2014, 2014
C. E. Scott, A. Rap, D. V. Spracklen, P. M. Forster, K. S. Carslaw, G. W. Mann, K. J. Pringle, N. Kivekäs, M. Kulmala, H. Lihavainen, and P. Tunved
Atmos. Chem. Phys., 14, 447–470, https://doi.org/10.5194/acp-14-447-2014, https://doi.org/10.5194/acp-14-447-2014, 2014
T. Yli-Juuti, K. Barsanti, L. Hildebrandt Ruiz, A.-J. Kieloaho, U. Makkonen, T. Petäjä, T. Ruuskanen, M. Kulmala, and I. Riipinen
Atmos. Chem. Phys., 13, 12507–12524, https://doi.org/10.5194/acp-13-12507-2013, https://doi.org/10.5194/acp-13-12507-2013, 2013
A. L. Corrigan, L. M. Russell, S. Takahama, M. Äijälä, M. Ehn, H. Junninen, J. Rinne, T. Petäjä, M. Kulmala, A. L. Vogel, T. Hoffmann, C. J. Ebben, F. M. Geiger, P. Chhabra, J. H. Seinfeld, D. R. Worsnop, W. Song, J. Auld, and J. Williams
Atmos. Chem. Phys., 13, 12233–12256, https://doi.org/10.5194/acp-13-12233-2013, https://doi.org/10.5194/acp-13-12233-2013, 2013
S. Dengel, D. Zona, T. Sachs, M. Aurela, M. Jammet, F. J. W. Parmentier, W. Oechel, and T. Vesala
Biogeosciences, 10, 8185–8200, https://doi.org/10.5194/bg-10-8185-2013, https://doi.org/10.5194/bg-10-8185-2013, 2013
C. J. Schumacher, C. Pöhlker, P. Aalto, V. Hiltunen, T. Petäjä, M. Kulmala, U. Pöschl, and J. A. Huffman
Atmos. Chem. Phys., 13, 11987–12001, https://doi.org/10.5194/acp-13-11987-2013, https://doi.org/10.5194/acp-13-11987-2013, 2013
A. Meyer, L. Tarvainen, A. Nousratpour, R. G. Björk, M. Ernfors, A. Grelle, Å Kasimir Klemedtsson, A. Lindroth, M. Räntfors, T. Rütting, G. Wallin, P. Weslien, and L. Klemedtsson
Biogeosciences, 10, 7739–7758, https://doi.org/10.5194/bg-10-7739-2013, https://doi.org/10.5194/bg-10-7739-2013, 2013
J. Kontkanen, K. E. J. Lehtinen, T. Nieminen, H. E. Manninen, K. Lehtipalo, V.-M. Kerminen, and M. Kulmala
Atmos. Chem. Phys., 13, 11391–11401, https://doi.org/10.5194/acp-13-11391-2013, https://doi.org/10.5194/acp-13-11391-2013, 2013
A. L. Vogel, M. Äijälä, A. L. Corrigan, H. Junninen, M. Ehn, T. Petäjä, D. R. Worsnop, M. Kulmala, L. M. Russell, J. Williams, and T. Hoffmann
Atmos. Chem. Phys., 13, 10933–10950, https://doi.org/10.5194/acp-13-10933-2013, https://doi.org/10.5194/acp-13-10933-2013, 2013
A. J. Ding, C. B. Fu, X. Q. Yang, J. N. Sun, T. Petäjä, V.-M. Kerminen, T. Wang, Y. Xie, E. Herrmann, L. F. Zheng, W. Nie, Q. Liu, X. L. Wei, and M. Kulmala
Atmos. Chem. Phys., 13, 10545–10554, https://doi.org/10.5194/acp-13-10545-2013, https://doi.org/10.5194/acp-13-10545-2013, 2013
M. Paramonov, P. P. Aalto, A. Asmi, N. Prisle, V.-M. Kerminen, M. Kulmala, and T. Petäjä
Atmos. Chem. Phys., 13, 10285–10301, https://doi.org/10.5194/acp-13-10285-2013, https://doi.org/10.5194/acp-13-10285-2013, 2013
N. Unger, K. Harper, Y. Zheng, N. Y. Kiang, I. Aleinov, A. Arneth, G. Schurgers, C. Amelynck, A. Goldstein, A. Guenther, B. Heinesch, C. N. Hewitt, T. Karl, Q. Laffineur, B. Langford, K. A. McKinney, P. Misztal, M. Potosnak, J. Rinne, S. Pressley, N. Schoon, and D. Serça
Atmos. Chem. Phys., 13, 10243–10269, https://doi.org/10.5194/acp-13-10243-2013, https://doi.org/10.5194/acp-13-10243-2013, 2013
M. R. Pennington, B. R. Bzdek, J. W. DePalma, J. N. Smith, A.-M. Kortelainen, L. Hildebrandt Ruiz, T. Petäjä, M. Kulmala, D. R. Worsnop, and M. V. Johnston
Atmos. Chem. Phys., 13, 10215–10225, https://doi.org/10.5194/acp-13-10215-2013, https://doi.org/10.5194/acp-13-10215-2013, 2013
S. A. K. Häkkinen, H. E. Manninen, T. Yli-Juuti, J. Merikanto, M. K. Kajos, T. Nieminen, S. D. D'Andrea, A. Asmi, J. R. Pierce, M. Kulmala, and I. Riipinen
Atmos. Chem. Phys., 13, 7665–7682, https://doi.org/10.5194/acp-13-7665-2013, https://doi.org/10.5194/acp-13-7665-2013, 2013
E. Järvinen, A. Virkkula, T. Nieminen, P. P. Aalto, E. Asmi, C. Lanconelli, M. Busetto, A. Lupi, R. Schioppo, V. Vitale, M. Mazzola, T. Petäjä, V.-M. Kerminen, and M. Kulmala
Atmos. Chem. Phys., 13, 7473–7487, https://doi.org/10.5194/acp-13-7473-2013, https://doi.org/10.5194/acp-13-7473-2013, 2013
D. Wimmer, K. Lehtipalo, A. Franchin, J. Kangasluoma, F. Kreissl, A. Kürten, A. Kupc, A. Metzger, J. Mikkilä, T. Petäjä, F. Riccobono, J. Vanhanen, M. Kulmala, and J. Curtius
Atmos. Meas. Tech., 6, 1793–1804, https://doi.org/10.5194/amt-6-1793-2013, https://doi.org/10.5194/amt-6-1793-2013, 2013
M. K. Kajos, H. Hakola, T. Holst, T. Nieminen, V. Tarvainen, T. Maximov, T. Petäjä, A. Arneth, and J. Rinne
Biogeosciences, 10, 4705–4719, https://doi.org/10.5194/bg-10-4705-2013, https://doi.org/10.5194/bg-10-4705-2013, 2013
A. J. Ding, C. B. Fu, X. Q. Yang, J. N. Sun, L. F. Zheng, Y. N. Xie, E. Herrmann, W. Nie, T. Petäjä, V.-M. Kerminen, and M. Kulmala
Atmos. Chem. Phys., 13, 5813–5830, https://doi.org/10.5194/acp-13-5813-2013, https://doi.org/10.5194/acp-13-5813-2013, 2013
O. Peltola, I. Mammarella, S. Haapanala, G. Burba, and T. Vesala
Biogeosciences, 10, 3749–3765, https://doi.org/10.5194/bg-10-3749-2013, https://doi.org/10.5194/bg-10-3749-2013, 2013
A. Hirsikko, V. Vakkari, P. Tiitta, J. Hatakka, V.-M. Kerminen, A.-M. Sundström, J. P. Beukes, H. E. Manninen, M. Kulmala, and L. Laakso
Atmos. Chem. Phys., 13, 5523–5532, https://doi.org/10.5194/acp-13-5523-2013, https://doi.org/10.5194/acp-13-5523-2013, 2013
H. Keskinen, A. Virtanen, J. Joutsensaari, G. Tsagkogeorgas, J. Duplissy, S. Schobesberger, M. Gysel, F. Riccobono, J. G. Slowik, F. Bianchi, T. Yli-Juuti, K. Lehtipalo, L. Rondo, M. Breitenlechner, A. Kupc, J. Almeida, A. Amorim, E. M. Dunne, A. J. Downard, S. Ehrhart, A. Franchin, M.K. Kajos, J. Kirkby, A. Kürten, T. Nieminen, V. Makhmutov, S. Mathot, P. Miettinen, A. Onnela, T. Petäjä, A. Praplan, F. D. Santos, S. Schallhart, M. Sipilä, Y. Stozhkov, A. Tomé, P. Vaattovaara, D. Wimmer, A. Prevot, J. Dommen, N. M. Donahue, R.C. Flagan, E. Weingartner, Y. Viisanen, I. Riipinen, A. Hansel, J. Curtius, M. Kulmala, D. R. Worsnop, U. Baltensperger, H. Wex, F. Stratmann, and A. Laaksonen
Atmos. Chem. Phys., 13, 5587–5600, https://doi.org/10.5194/acp-13-5587-2013, https://doi.org/10.5194/acp-13-5587-2013, 2013
A. I. Hienola, J.-P. Pietikäinen, D. Jacob, R. Pozdun, T. Petäjä, A.-P. Hyvärinen, L. Sogacheva, V.-M. Kerminen, M. Kulmala, and A. Laaksonen
Atmos. Chem. Phys., 13, 4033–4055, https://doi.org/10.5194/acp-13-4033-2013, https://doi.org/10.5194/acp-13-4033-2013, 2013
M. Boy, D. Mogensen, S. Smolander, L. Zhou, T. Nieminen, P. Paasonen, C. Plass-Dülmer, M. Sipilä, T. Petäjä, L. Mauldin, H. Berresheim, and M. Kulmala
Atmos. Chem. Phys., 13, 3865–3879, https://doi.org/10.5194/acp-13-3865-2013, https://doi.org/10.5194/acp-13-3865-2013, 2013
A. L. Vogel, M. Äijälä, M. Brüggemann, M. Ehn, H. Junninen, T. Petäjä, D. R. Worsnop, M. Kulmala, J. Williams, and T. Hoffmann
Atmos. Meas. Tech., 6, 431–443, https://doi.org/10.5194/amt-6-431-2013, https://doi.org/10.5194/amt-6-431-2013, 2013
V. Vakkari, J. P. Beukes, H. Laakso, D. Mabaso, J. J. Pienaar, M. Kulmala, and L. Laakso
Atmos. Chem. Phys., 13, 1751–1770, https://doi.org/10.5194/acp-13-1751-2013, https://doi.org/10.5194/acp-13-1751-2013, 2013
M. C. Braakhekke, T. Wutzler, C. Beer, J. Kattge, M. Schrumpf, B. Ahrens, I. Schöning, M. R. Hoosbeek, B. Kruijt, P. Kabat, and M. Reichstein
Biogeosciences, 10, 399–420, https://doi.org/10.5194/bg-10-399-2013, https://doi.org/10.5194/bg-10-399-2013, 2013
J. Leppä, S. Gagné, L. Laakso, H. E. Manninen, K. E. J. Lehtinen, M. Kulmala, and V.-M. Kerminen
Atmos. Chem. Phys., 13, 463–486, https://doi.org/10.5194/acp-13-463-2013, https://doi.org/10.5194/acp-13-463-2013, 2013
E. Herrmann, A. J. Ding, T. Petäjä, X. Q. Yang, J. N. Sun, X. M. Qi, H. Manninen, J. Hakala, T. Nieminen, P. P. Aalto, V.-M. Kerminen, M. Kulmala, and C. B. Fu
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-13-1455-2013, https://doi.org/10.5194/acpd-13-1455-2013, 2013
Revised manuscript not accepted
V.-M. Kerminen, M. Paramonov, T. Anttila, I. Riipinen, C. Fountoukis, H. Korhonen, E. Asmi, L. Laakso, H. Lihavainen, E. Swietlicki, B. Svenningsson, A. Asmi, S. N. Pandis, M. Kulmala, and T. Petäjä
Atmos. Chem. Phys., 12, 12037–12059, https://doi.org/10.5194/acp-12-12037-2012, https://doi.org/10.5194/acp-12-12037-2012, 2012
T. Viskari, E. Asmi, P. Kolmonen, H. Vuollekoski, T. Petäjä, and H. Järvinen
Atmos. Chem. Phys., 12, 11767–11779, https://doi.org/10.5194/acp-12-11767-2012, https://doi.org/10.5194/acp-12-11767-2012, 2012
T. Viskari, E. Asmi, A. Virkkula, P. Kolmonen, T. Petäjä, and H. Järvinen
Atmos. Chem. Phys., 12, 11781–11793, https://doi.org/10.5194/acp-12-11781-2012, https://doi.org/10.5194/acp-12-11781-2012, 2012
Related subject area
Subject: Biosphere Interactions | Research Activity: Atmospheric Modelling and Data Analysis | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
Why do inverse models disagree? A case study with two European CO2 inversions
Net ecosystem exchange (NEE) estimates 2006–2019 over Europe from a pre-operational ensemble-inversion system
Interpreting machine learning prediction of fire emissions and comparison with FireMIP process-based models
Distinguishing the impacts of natural and anthropogenic aerosols on global gross primary productivity through diffuse fertilization effect
Was Australia a sink or source of CO2 in 2015? Data assimilation using OCO-2 satellite measurements
CO2-equivalence metrics for surface albedo change based on the radiative forcing concept: a critical review
Effects of aerosol dynamics and gas–particle conversion on dry deposition of inorganic reactive nitrogen in a temperate forest
Ozone–vegetation feedback through dry deposition and isoprene emissions in a global chemistry–carbon–climate model
Pathway dependence of ecosystem responses in China to 1.5 °C global warming
A model-based analysis of foliar NOx deposition
Quantifying the UK's carbon dioxide flux: an atmospheric inverse modelling approach using a regional measurement network
Technical note: How are NH3 dry deposition estimates affected by combining the LOTOS-EUROS model with IASI-NH3 satellite observations?
Isoprene and monoterpene emissions in south-east Australia: comparison of a multi-layer canopy model with MEGAN and with atmospheric observations
Particulate matter air pollution may offset ozone damage to global crop production
Sensitivity of stomatal conductance to soil moisture: implications for tropospheric ozone
The influence of idealized surface heterogeneity on virtual turbulent flux measurements
Technical Note: Atmospheric CO2 inversions on the mesoscale using data-driven prior uncertainties: methodology and system evaluation
Atmospheric CO2 inversions on the mesoscale using data-driven prior uncertainties: quantification of the European terrestrial CO2 fluxes
Modeling the contributions of global air temperature, synoptic-scale phenomena and soil moisture to near-surface static energy variability using artificial neural networks
Future inhibition of ecosystem productivity by increasing wildfire pollution over boreal North America
Multi-model ensemble simulations of olive pollen distribution in Europe in 2014: current status and outlook
Modeling soil organic carbon dynamics and their driving factors in the main global cereal cropping systems
A wedge strategy for mitigation of urban warming in future climate scenarios
The boundary condition for vertical velocity and its interdependence with surface gas exchange
Pan-Eurasian Experiment (PEEX): towards a holistic understanding of the feedbacks and interactions in the land–atmosphere–ocean–society continuum in the northern Eurasian region
Greenhouse gas simulations with a coupled meteorological and transport model: the predictability of CO2
Increasing summer net CO2 uptake in high northern ecosystems inferred from atmospheric inversions and comparisons to remote-sensing NDVI
A study of the influence of forest gaps on fire–atmosphere interactions
Stratospheric sulfate geoengineering could enhance the terrestrial photosynthesis rate
Distinguishing the drivers of trends in land carbon fluxes and plant volatile emissions over the past 3 decades
Granger causality from changes in level of atmospheric CO2 to global surface temperature and the El Niño–Southern Oscillation, and a candidate mechanism in global photosynthesis
MACC regional multi-model ensemble simulations of birch pollen dispersion in Europe
Stably stratified canopy flow in complex terrain
Fire emission heights in the climate system – Part 1: Global plume height patterns simulated by ECHAM6-HAM2
Fire emission heights in the climate system – Part 2: Impact on transport, black carbon concentrations and radiation
Reliable, robust and realistic: the three R's of next-generation land-surface modelling
Biases in atmospheric CO2 estimates from correlated meteorology modeling errors
Carbon balance of China constrained by CONTRAIL aircraft CO2 measurements
Greenhouse gas network design using backward Lagrangian particle dispersion modelling − Part 1: Methodology and Australian test case
Sensitivity analysis of an updated bidirectional air–surface exchange model for elemental mercury vapor
Nitrous oxide emissions 1999 to 2009 from a global atmospheric inversion
Quantifying the constraint of biospheric process parameters by CO2 concentration and flux measurement networks through a carbon cycle data assimilation system
Photosynthesis-dependent isoprene emission from leaf to planet in a global carbon-chemistry-climate model
Present and future nitrogen deposition to national parks in the United States: critical load exceedances
Global mapping of maximum emission heights and resulting vertical profiles of wildfire emissions
Scorched Earth: how will changes in the strength of the vegetation sink to ozone deposition affect human health and ecosystems?
The effect of climate and climate change on ammonia emissions in Europe
Observing the continental-scale carbon balance: assessment of sampling complementarity and redundancy in a terrestrial assimilation system by means of quantitative network design
CO2 flux estimation errors associated with moist atmospheric processes
DO3SE modelling of soil moisture to determine ozone flux to forest trees
Saqr Munassar, Guillaume Monteil, Marko Scholze, Ute Karstens, Christian Rödenbeck, Frank-Thomas Koch, Kai U. Totsche, and Christoph Gerbig
Atmos. Chem. Phys., 23, 2813–2828, https://doi.org/10.5194/acp-23-2813-2023, https://doi.org/10.5194/acp-23-2813-2023, 2023
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Using different transport models results in large errors in optimized fluxes in the atmospheric inversions. Boundary conditions and inversion system configurations lead to a smaller but non-negligible impact. The findings highlight the importance to validate transport models for further developments but also to properly account for such errors in inverse modelling. This will help narrow the convergence of gas estimates reported in the scientific literature from different inversion frameworks.
Saqr Munassar, Christian Rödenbeck, Frank-Thomas Koch, Kai U. Totsche, Michał Gałkowski, Sophia Walther, and Christoph Gerbig
Atmos. Chem. Phys., 22, 7875–7892, https://doi.org/10.5194/acp-22-7875-2022, https://doi.org/10.5194/acp-22-7875-2022, 2022
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The results obtained from ensembles of inversions over 13 years show the largest spread in the a posteriori fluxes over the station set ensemble. Using different prior fluxes in the inversions led to a smaller impact. Drought occurrences in 2018 and 2019 affected CO2 fluxes as seen in net ecosystem exchange estimates. Our study highlights the importance of expanding the atmospheric site network across Europe to better constrain CO2 fluxes in inverse modelling.
Sally S.-C. Wang, Yun Qian, L. Ruby Leung, and Yang Zhang
Atmos. Chem. Phys., 22, 3445–3468, https://doi.org/10.5194/acp-22-3445-2022, https://doi.org/10.5194/acp-22-3445-2022, 2022
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This study develops an interpretable machine learning (ML) model predicting monthly PM2.5 fire emission over the contiguous US at 0.25° resolution and compares the prediction skills of the ML and process-based models. The comparison facilitates attributions of model biases and better understanding of the strengths and uncertainties in the two types of models at regional scales, for informing future model development and their applications in fire emission projection.
Hao Zhou, Xu Yue, Yadong Lei, Chenguang Tian, Jun Zhu, Yimian Ma, Yang Cao, Xixi Yin, and Zhiding Zhang
Atmos. Chem. Phys., 22, 693–709, https://doi.org/10.5194/acp-22-693-2022, https://doi.org/10.5194/acp-22-693-2022, 2022
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Aerosols enhance plant photosynthesis by increasing diffuse radiation. In this study, we found that the aerosol impacts are quite different for varied species. Scattering aerosols such as sulfate and organic carbon promote photosynthesis while absorbing aerosols such as black carbon have negative impacts. Earth system models should consider the impacts of cloud and aerosol species on terrestrial ecosystems so as to better predict carbon cycles under different emission scenarios.
Yohanna Villalobos, Peter J. Rayner, Jeremy D. Silver, Steven Thomas, Vanessa Haverd, Jürgen Knauer, Zoë M. Loh, Nicholas M. Deutscher, David W. T. Griffith, and David F. Pollard
Atmos. Chem. Phys., 21, 17453–17494, https://doi.org/10.5194/acp-21-17453-2021, https://doi.org/10.5194/acp-21-17453-2021, 2021
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Semi-arid ecosystems such as those in Australia are evolving and might play an essential role in the future of climate change. We use carbon dioxide concentrations derived from the OCO-2 satellite instrument and a regional transport model to understand if Australia was a carbon sink or source of CO2 in 2015. Our research's main findings suggest that Australia acted as a carbon sink of about −0.41 ± 0.08 petagrams of carbon in 2015, driven primarily by savanna and sparsely vegetated ecosystems.
Ryan M. Bright and Marianne T. Lund
Atmos. Chem. Phys., 21, 9887–9907, https://doi.org/10.5194/acp-21-9887-2021, https://doi.org/10.5194/acp-21-9887-2021, 2021
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Humans affect the reflective properties (albedo) of Earth's surface and the amount of solar energy that it absorbs, in turn affecting climate. In recent years, a variety of climate metrics have been applied to characterize albedo perturbations in terms of their
CO2-equivalenteffects, despite the lack of scientific consensus surrounding the methods behind them. We review these metrics, evaluate their (de)merits, provide guidance for future application, and suggest avenues for future research.
Genki Katata, Kazuhide Matsuda, Atsuyuki Sorimachi, Mizuo Kajino, and Kentaro Takagi
Atmos. Chem. Phys., 20, 4933–4949, https://doi.org/10.5194/acp-20-4933-2020, https://doi.org/10.5194/acp-20-4933-2020, 2020
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This work quantified the role of aerosol dynamics and gas–particle conversion processes in the dry deposition of inorganic reactive nitrogen using a new multilayer land surface model. It also revealed a potential impact of the above processes on improving the predictive accuracy of chemical transport models.
Cheng Gong, Yadong Lei, Yimian Ma, Xu Yue, and Hong Liao
Atmos. Chem. Phys., 20, 3841–3857, https://doi.org/10.5194/acp-20-3841-2020, https://doi.org/10.5194/acp-20-3841-2020, 2020
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We evaluate ozone–vegetation feedback using a fully coupled chemistry–carbon–climate global model (ModelE2-YIBs). Ozone damage to photosynthesis, stomatal conductance, and isoprene emissions parameterized by different schemes and sensitivities is jointly considered. In general, surface ozone concentrations are increased due to ozone–vegetation interactions, especially over the regions with a high ambient ozone level such as the eastern US, eastern China, and western Europe.
Xu Yue, Hong Liao, Huijun Wang, Tianyi Zhang, Nadine Unger, Stephen Sitch, Zhaozhong Feng, and Jia Yang
Atmos. Chem. Phys., 20, 2353–2366, https://doi.org/10.5194/acp-20-2353-2020, https://doi.org/10.5194/acp-20-2353-2020, 2020
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We explore ecosystem responses in China to 1.5 °C global warming under stabilized versus transient pathways. Remarkably, GPP shows 30 % higher enhancement in the stabilized than the transient pathway because of the lower ozone (smaller damages to photosynthesis) and fewer aerosols (higher light availability) in the former pathway. Our analyses suggest that an associated reduction of CO2 and pollution emissions brings more benefits to ecosystems in China via 1.5 °C global warming.
Erin R. Delaria and Ronald C. Cohen
Atmos. Chem. Phys., 20, 2123–2141, https://doi.org/10.5194/acp-20-2123-2020, https://doi.org/10.5194/acp-20-2123-2020, 2020
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Uptake of nitrogen dioxide (NO2) through pores in the surfaces of leaves has been identified as a significant, but inadequately understood, loss process of atmospheric nitrogen oxides. We have constructed a simple model for examining the impact of NO2 foliar uptake on the atmospheric chemistry of nitrogen oxides. We show that an accurate representation in atmospheric models of the effects of weather and soil conditions on leaf NO2 uptake may be important for accurately predicting NO2 deposition.
Emily D. White, Matthew Rigby, Mark F. Lunt, T. Luke Smallman, Edward Comyn-Platt, Alistair J. Manning, Anita L. Ganesan, Simon O'Doherty, Ann R. Stavert, Kieran Stanley, Mathew Williams, Peter Levy, Michel Ramonet, Grant L. Forster, Andrew C. Manning, and Paul I. Palmer
Atmos. Chem. Phys., 19, 4345–4365, https://doi.org/10.5194/acp-19-4345-2019, https://doi.org/10.5194/acp-19-4345-2019, 2019
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Understanding carbon dioxide (CO2) fluxes from the terrestrial biosphere on a national scale is important for evaluating land use strategies to mitigate climate change. We estimate emissions of CO2 from the UK biosphere using atmospheric data in a top-down approach. Our findings show that bottom-up estimates from models of biospheric fluxes overestimate the amount of CO2 uptake in summer. This suggests these models wrongly estimate or omit key processes, e.g. land disturbance due to harvest.
Shelley C. van der Graaf, Enrico Dammers, Martijn Schaap, and Jan Willem Erisman
Atmos. Chem. Phys., 18, 13173–13196, https://doi.org/10.5194/acp-18-13173-2018, https://doi.org/10.5194/acp-18-13173-2018, 2018
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A combination of NH3 satellite observations from IASI and the LOTOS-EUROS model is used to derive NH3 surface concentrations and dry deposition fluxes over Europe. The results were evaluated using surface measurements (EMEP, LML, MAN) and a sensitivity study. This is a first step in further integration of surface measurements, satellite observations and an atmospheric transport model to derive accurate NH3 surface concentrations and dry deposition fluxes on a large scale.
Kathryn M. Emmerson, Martin E. Cope, Ian E. Galbally, Sunhee Lee, and Peter F. Nelson
Atmos. Chem. Phys., 18, 7539–7556, https://doi.org/10.5194/acp-18-7539-2018, https://doi.org/10.5194/acp-18-7539-2018, 2018
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We compare the CSIRO in-house biogenic emissions model (ABCGEM) with the Model of Emissions of Gases and Aerosols from Nature (MEGAN), for eucalypt-rich south-east Australia. Differences in emissions are not only due to the emission factors, but also how these emission factors are processed. ABCGEM assumes monoterpenes are not light dependent, whilst MEGAN does. Comparison with observations suggests that Australian monoterpenes may not be as light dependent as other vegetation globally.
Luke D. Schiferl and Colette L. Heald
Atmos. Chem. Phys., 18, 5953–5966, https://doi.org/10.5194/acp-18-5953-2018, https://doi.org/10.5194/acp-18-5953-2018, 2018
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Global population growth and industrialization have contributed to poor air quality worldwide, and increasing population will put pressure on global food production. We therefore assess how air pollution may impact crop growth. Ozone has previously been shown to damage crops. We demonstrate that the impact of particles associated with enhanced light scattering promotes growth, offsetting much, if not all, ozone damage. This has implications for air quality management and global food security.
Alessandro Anav, Chiara Proietti, Laurent Menut, Stefano Carnicelli, Alessandra De Marco, and Elena Paoletti
Atmos. Chem. Phys., 18, 5747–5763, https://doi.org/10.5194/acp-18-5747-2018, https://doi.org/10.5194/acp-18-5747-2018, 2018
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Soil moisture and water stress play a pivotal role in regulating stomatal behaviour of plants; however, the role of water availability is often neglected in atmospheric chemistry modelling studies.
We show how dry deposition significantly declines when soil moisture is used to regulate the stomatal opening, mainly in semi-arid environments. Despite the fact that dry deposition occurs from the top of canopy to ground level, it affects the concentration of gases remaining in the lower atmosphere.
Frederik De Roo and Matthias Mauder
Atmos. Chem. Phys., 18, 5059–5074, https://doi.org/10.5194/acp-18-5059-2018, https://doi.org/10.5194/acp-18-5059-2018, 2018
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We investigate the mismatch between incoming energy and the turbulent flux of sensible heat at the Earth's surface and how surface heterogeneity affects this imbalance. To resolve the turbulent fluxes we employ large-eddy simulations. We study terrain with different heterogeneity lengths and quantify the contributions of advection by the mean flow and horizontal flux-divergence in the surface energy budget. We find that the latter contributions depend on the scale of the heterogeneity length.
Panagiotis Kountouris, Christoph Gerbig, Christian Rödenbeck, Ute Karstens, Thomas Frank Koch, and Martin Heimann
Atmos. Chem. Phys., 18, 3027–3045, https://doi.org/10.5194/acp-18-3027-2018, https://doi.org/10.5194/acp-18-3027-2018, 2018
Panagiotis Kountouris, Christoph Gerbig, Christian Rödenbeck, Ute Karstens, Thomas F. Koch, and Martin Heimann
Atmos. Chem. Phys., 18, 3047–3064, https://doi.org/10.5194/acp-18-3047-2018, https://doi.org/10.5194/acp-18-3047-2018, 2018
Sara C. Pryor, Ryan C. Sullivan, and Justin T. Schoof
Atmos. Chem. Phys., 17, 14457–14471, https://doi.org/10.5194/acp-17-14457-2017, https://doi.org/10.5194/acp-17-14457-2017, 2017
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The air temperature and water vapor content are increasing globally due to the increased concentration of "heat-trapping" (greenhouse) gases. But not all regions are warming at the same rate. This analysis is designed to improve understanding of the causes of recent trends and year-to-year variability in summertime heat indices over the eastern US and to present a new model that can be used to make projections of future events that may cause loss of life and/or decreased human well-being.
Xu Yue, Susanna Strada, Nadine Unger, and Aihui Wang
Atmos. Chem. Phys., 17, 13699–13719, https://doi.org/10.5194/acp-17-13699-2017, https://doi.org/10.5194/acp-17-13699-2017, 2017
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Climate change will significantly increase wildfire emissions in boreal North America by the midcentury, leading to increased surface ozone and atmospheric aerosols. These air pollutants can affect vegetation photosynthesis through stomatal uptake (for ozone) and radiative and climatic perturbations (for aerosols). Using a carbon–chemistry–climate model, we estimate trivial ozone vegetation damages but significant aerosol-induced reduction in ecosystem productivity by the 2050s.
Mikhail Sofiev, Olga Ritenberga, Roberto Albertini, Joaquim Arteta, Jordina Belmonte, Carmi Geller Bernstein, Maira Bonini, Sevcan Celenk, Athanasios Damialis, John Douros, Hendrik Elbern, Elmar Friese, Carmen Galan, Gilles Oliver, Ivana Hrga, Rostislav Kouznetsov, Kai Krajsek, Donat Magyar, Jonathan Parmentier, Matthieu Plu, Marje Prank, Lennart Robertson, Birthe Marie Steensen, Michel Thibaudon, Arjo Segers, Barbara Stepanovich, Alvaro M. Valdebenito, Julius Vira, and Despoina Vokou
Atmos. Chem. Phys., 17, 12341–12360, https://doi.org/10.5194/acp-17-12341-2017, https://doi.org/10.5194/acp-17-12341-2017, 2017
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This work presents the features and evaluates the quality of the Copernicus Atmospheric Monitoring Service forecasts of olive pollen distribution in Europe. It is shown that the models can predict the main features of the observed pollen distribution but have more difficulties in capturing the season start and end, which appeared shifted by a few days. We also demonstrated that the combined use of model predictions with up-to-date measurements (data fusion) can strongly improve the results.
Guocheng Wang, Wen Zhang, Wenjuan Sun, Tingting Li, and Pengfei Han
Atmos. Chem. Phys., 17, 11849–11859, https://doi.org/10.5194/acp-17-11849-2017, https://doi.org/10.5194/acp-17-11849-2017, 2017
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Cropland soil carbon sequestration contribute to not only climate change mitigation but also to sustainable agricultural production. This paper investigates soil carbon dynamics across the global main cereal cropping systems at a fine spatial resolution, using a modeling approach based on state-of-the-art databases of soil and climate. The key environmental controls on soil carbon changes were also identified.
Lei Zhao, Xuhui Lee, and Natalie M. Schultz
Atmos. Chem. Phys., 17, 9067–9080, https://doi.org/10.5194/acp-17-9067-2017, https://doi.org/10.5194/acp-17-9067-2017, 2017
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Heat stress associated with climate change is one of most severe threats to human society. The problem is further compounded in urban areas by urban heat islands (UHIs). We use an urban climate model to evaluate the cooling benefits of active urban heat mitigation strategies both individually and collectively. We show that by forming UHI mitigation wedges, these strategies have the potential to significantly reduce the UHI effect plus warming induced by greenhouse gases.
Andrew S. Kowalski
Atmos. Chem. Phys., 17, 8177–8187, https://doi.org/10.5194/acp-17-8177-2017, https://doi.org/10.5194/acp-17-8177-2017, 2017
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An analysis based on physical conservation law demonstrates that surface–atmosphere exchanges include a non-diffusive component. This implies the need to revise flux gradient relationships including eddy diffusivities in micrometeorology and stomatal conductances in plant physiology.
Hanna K. Lappalainen, Veli-Matti Kerminen, Tuukka Petäjä, Theo Kurten, Aleksander Baklanov, Anatoly Shvidenko, Jaana Bäck, Timo Vihma, Pavel Alekseychik, Meinrat O. Andreae, Stephen R. Arnold, Mikhail Arshinov, Eija Asmi, Boris Belan, Leonid Bobylev, Sergey Chalov, Yafang Cheng, Natalia Chubarova, Gerrit de Leeuw, Aijun Ding, Sergey Dobrolyubov, Sergei Dubtsov, Egor Dyukarev, Nikolai Elansky, Kostas Eleftheriadis, Igor Esau, Nikolay Filatov, Mikhail Flint, Congbin Fu, Olga Glezer, Aleksander Gliko, Martin Heimann, Albert A. M. Holtslag, Urmas Hõrrak, Juha Janhunen, Sirkku Juhola, Leena Järvi, Heikki Järvinen, Anna Kanukhina, Pavel Konstantinov, Vladimir Kotlyakov, Antti-Jussi Kieloaho, Alexander S. Komarov, Joni Kujansuu, Ilmo Kukkonen, Ella-Maria Duplissy, Ari Laaksonen, Tuomas Laurila, Heikki Lihavainen, Alexander Lisitzin, Alexsander Mahura, Alexander Makshtas, Evgeny Mareev, Stephany Mazon, Dmitry Matishov, Vladimir Melnikov, Eugene Mikhailov, Dmitri Moisseev, Robert Nigmatulin, Steffen M. Noe, Anne Ojala, Mari Pihlatie, Olga Popovicheva, Jukka Pumpanen, Tatjana Regerand, Irina Repina, Aleksei Shcherbinin, Vladimir Shevchenko, Mikko Sipilä, Andrey Skorokhod, Dominick V. Spracklen, Hang Su, Dmitry A. Subetto, Junying Sun, Arkady Y. Terzhevik, Yuri Timofeyev, Yuliya Troitskaya, Veli-Pekka Tynkkynen, Viacheslav I. Kharuk, Nina Zaytseva, Jiahua Zhang, Yrjö Viisanen, Timo Vesala, Pertti Hari, Hans Christen Hansson, Gennady G. Matvienko, Nikolai S. Kasimov, Huadong Guo, Valery Bondur, Sergej Zilitinkevich, and Markku Kulmala
Atmos. Chem. Phys., 16, 14421–14461, https://doi.org/10.5194/acp-16-14421-2016, https://doi.org/10.5194/acp-16-14421-2016, 2016
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After kick off in 2012, the Pan-Eurasian Experiment (PEEX) program has expanded fast and today the multi-disciplinary research community covers ca. 80 institutes and a network of ca. 500 scientists from Europe, Russia, and China. Here we introduce scientific topics relevant in this context. This is one of the first multi-disciplinary overviews crossing scientific boundaries, from atmospheric sciences to socio-economics and social sciences.
Saroja M. Polavarapu, Michael Neish, Monique Tanguay, Claude Girard, Jean de Grandpré, Kirill Semeniuk, Sylvie Gravel, Shuzhan Ren, Sébastien Roche, Douglas Chan, and Kimberly Strong
Atmos. Chem. Phys., 16, 12005–12038, https://doi.org/10.5194/acp-16-12005-2016, https://doi.org/10.5194/acp-16-12005-2016, 2016
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CO2 predictions are used to compute model–data mismatches when estimating surfaces fluxes using atmospheric observations together with an atmospheric transport model. By isolating the component of transport error which is due to uncertain meteorological analyses, it is demonstrated that CO2 can only be defined on large spatial scales. Thus, there is a spatial scale below which we cannot infer fluxes simply due to the fact that meteorological analyes are imperfect.
Lisa R. Welp, Prabir K. Patra, Christian Rödenbeck, Rama Nemani, Jian Bi, Stephen C. Piper, and Ralph F. Keeling
Atmos. Chem. Phys., 16, 9047–9066, https://doi.org/10.5194/acp-16-9047-2016, https://doi.org/10.5194/acp-16-9047-2016, 2016
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Boreal and arctic ecosystems have been responding to elevated temperatures and atmospheric CO2 over the last decades. It is not clear if these ecosystems are sequestering more carbon or possibly becoming sources. This is an important feedback of the carbon cycle to global warming. We studied monthly biological land CO2 fluxes inferred from atmospheric CO2 concentrations using inverse models and found that net summer CO2 uptake increased, resulting in a small increase in annual CO2 uptake.
Michael T. Kiefer, Warren E. Heilman, Shiyuan Zhong, Joseph J. Charney, and Xindi Bian
Atmos. Chem. Phys., 16, 8499–8509, https://doi.org/10.5194/acp-16-8499-2016, https://doi.org/10.5194/acp-16-8499-2016, 2016
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Studies of fire–atmosphere interactions in horizontally heterogeneous forests are limited in number. This study considers the sensitivity of fire-perturbed variables (e.g., vertical velocity, turbulent kinetic energy) to gaps in forest cover using ARPS-CANOPY, an atmospheric numerical model with a canopy sub-model. Results show that the atmosphere is most sensitive to the fire when the gap is centered on the fire and least sensitive when the gap is upstream of the fire.
L. Xia, A. Robock, S. Tilmes, and R. R. Neely III
Atmos. Chem. Phys., 16, 1479–1489, https://doi.org/10.5194/acp-16-1479-2016, https://doi.org/10.5194/acp-16-1479-2016, 2016
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Climate model simulations show that stratospheric sulfate geoengineering could impact the terrestrial carbon cycle by enhancing the carbon sink. Enhanced downward diffuse radiation, combined with cooling, could stimulate plants to grow more and absorb more carbon dioxide. This beneficial impact of stratospheric sulfate geoengineering would need to be balanced by a large number of potential risks in any future decisions about implementation of geoengineering.
X. Yue, N. Unger, and Y. Zheng
Atmos. Chem. Phys., 15, 11931–11948, https://doi.org/10.5194/acp-15-11931-2015, https://doi.org/10.5194/acp-15-11931-2015, 2015
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We estimate decadal trends in land carbon fluxes and emissions of biogenic volatile organic compounds (BVOCs) during 1982-2011, with a focus on the feedback from biosphere (such as tree growth and phenology). Increases of LAI at peak season accounts for ~25% of the trends in GPP and isoprene emissions at the northern lands. However, phenological change alone does not promote regional carbon uptake and BVOC emissions.
L. M. W. Leggett and D. A. Ball
Atmos. Chem. Phys., 15, 11571–11592, https://doi.org/10.5194/acp-15-11571-2015, https://doi.org/10.5194/acp-15-11571-2015, 2015
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The previously expected linear relationship between atmospheric CO2 and climate variables including temperature is showing an increasing mismatch. This paper nonetheless provides fresh and possibly definitive support for a major relationship between CO2 and climate. Granger causality analysis provides evidence that change in level not level of CO2 primarily influences both global temperature and the El Niño–Southern Oscillation. The results may contribute to the prediction of future climate.
M. Sofiev, U. Berger, M. Prank, J. Vira, J. Arteta, J. Belmonte, K.-C. Bergmann, F. Chéroux, H. Elbern, E. Friese, C. Galan, R. Gehrig, D. Khvorostyanov, R. Kranenburg, U. Kumar, V. Marécal, F. Meleux, L. Menut, A.-M. Pessi, L. Robertson, O. Ritenberga, V. Rodinkova, A. Saarto, A. Segers, E. Severova, I. Sauliene, P. Siljamo, B. M. Steensen, E. Teinemaa, M. Thibaudon, and V.-H. Peuch
Atmos. Chem. Phys., 15, 8115–8130, https://doi.org/10.5194/acp-15-8115-2015, https://doi.org/10.5194/acp-15-8115-2015, 2015
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The paper presents the first ensemble modelling experiment for forecasting the atmospheric dispersion of birch pollen in Europe. The study included 7 models of MACC-ENS tested over the season of 2010 and applied for 2013 in forecasting and reanalysis modes. The results were compared with observations in 11 countries, members of European Aeroallergen Network. The models successfully reproduced the timing of the unusually late season of 2013 but had more difficulties with absolute concentration.
X. Xu, C. Yi, and E. Kutter
Atmos. Chem. Phys., 15, 7457–7470, https://doi.org/10.5194/acp-15-7457-2015, https://doi.org/10.5194/acp-15-7457-2015, 2015
A. Veira, S. Kloster, S. Wilkenskjeld, and S. Remy
Atmos. Chem. Phys., 15, 7155–7171, https://doi.org/10.5194/acp-15-7155-2015, https://doi.org/10.5194/acp-15-7155-2015, 2015
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We discuss the representation of wildfire emission heights in global climate models. Our implementation of a simple, semi-empirical plume height parametrization in the aerosol-climate model ECHAM6-HAM2 shows reasonable agreement with observations and with a more complex plume rise model. In contrast, prescribed emission heights, which do not consider the intensity of individual fires, fail to adequately simulate global plume height patterns. Diurnal and seasonal cycles are of minor importance.
A. Veira, S. Kloster, N. A. J. Schutgens, and J. W. Kaiser
Atmos. Chem. Phys., 15, 7173–7193, https://doi.org/10.5194/acp-15-7173-2015, https://doi.org/10.5194/acp-15-7173-2015, 2015
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Global aerosol-climate models usually prescribe wildfire emission injections at fixed atmospheric levels. Here, we quantify the impact of prescribed and parametrized emission heights on aerosol long-range transport and radiation. For global emission height changes of 1.5-3.5km, we find a top-of-atmosphere radiative forcing of 0.05-0.1Wm-2. Replacing prescribed emission heights by a simple plume height parametrization only marginally improves the model performance in aerosol optical thickness.
I. C. Prentice, X. Liang, B. E. Medlyn, and Y.-P. Wang
Atmos. Chem. Phys., 15, 5987–6005, https://doi.org/10.5194/acp-15-5987-2015, https://doi.org/10.5194/acp-15-5987-2015, 2015
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Land surface models (LSMs) describe how carbon and water fluxes react to environmental change. They are key component of climate models, yet they differ enormously. Many perform poorly, despite having many parameters. We outline a development strategy emphasizing robustness, reliability and realism, none of which is guaranteed by complexity alone. We propose multiple constraints, benchmarking and data assimilation, and representing unresolved processes stochastically, as tools in this endeavour.
S. M. Miller, M. N. Hayek, A. E. Andrews, I. Fung, and J. Liu
Atmos. Chem. Phys., 15, 2903–2914, https://doi.org/10.5194/acp-15-2903-2015, https://doi.org/10.5194/acp-15-2903-2015, 2015
F. Jiang, H. M. Wang, J. M. Chen, T. Machida, L. X. Zhou, W. M. Ju, H. Matsueda, and Y. Sawa
Atmos. Chem. Phys., 14, 10133–10144, https://doi.org/10.5194/acp-14-10133-2014, https://doi.org/10.5194/acp-14-10133-2014, 2014
T. Ziehn, A. Nickless, P. J. Rayner, R. M. Law, G. Roff, and P. Fraser
Atmos. Chem. Phys., 14, 9363–9378, https://doi.org/10.5194/acp-14-9363-2014, https://doi.org/10.5194/acp-14-9363-2014, 2014
X. Wang, C.-J. Lin, and X. Feng
Atmos. Chem. Phys., 14, 6273–6287, https://doi.org/10.5194/acp-14-6273-2014, https://doi.org/10.5194/acp-14-6273-2014, 2014
R. L. Thompson, F. Chevallier, A. M. Crotwell, G. Dutton, R. L. Langenfelds, R. G. Prinn, R. F. Weiss, Y. Tohjima, T. Nakazawa, P. B. Krummel, L. P. Steele, P. Fraser, S. O'Doherty, K. Ishijima, and S. Aoki
Atmos. Chem. Phys., 14, 1801–1817, https://doi.org/10.5194/acp-14-1801-2014, https://doi.org/10.5194/acp-14-1801-2014, 2014
E. N. Koffi, P. J. Rayner, M. Scholze, F. Chevallier, and T. Kaminski
Atmos. Chem. Phys., 13, 10555–10572, https://doi.org/10.5194/acp-13-10555-2013, https://doi.org/10.5194/acp-13-10555-2013, 2013
N. Unger, K. Harper, Y. Zheng, N. Y. Kiang, I. Aleinov, A. Arneth, G. Schurgers, C. Amelynck, A. Goldstein, A. Guenther, B. Heinesch, C. N. Hewitt, T. Karl, Q. Laffineur, B. Langford, K. A. McKinney, P. Misztal, M. Potosnak, J. Rinne, S. Pressley, N. Schoon, and D. Serça
Atmos. Chem. Phys., 13, 10243–10269, https://doi.org/10.5194/acp-13-10243-2013, https://doi.org/10.5194/acp-13-10243-2013, 2013
R. A. Ellis, D. J. Jacob, M. P. Sulprizio, L. Zhang, C. D. Holmes, B. A. Schichtel, T. Blett, E. Porter, L. H. Pardo, and J. A. Lynch
Atmos. Chem. Phys., 13, 9083–9095, https://doi.org/10.5194/acp-13-9083-2013, https://doi.org/10.5194/acp-13-9083-2013, 2013
M. Sofiev, R. Vankevich, T. Ermakova, and J. Hakkarainen
Atmos. Chem. Phys., 13, 7039–7052, https://doi.org/10.5194/acp-13-7039-2013, https://doi.org/10.5194/acp-13-7039-2013, 2013
L. D. Emberson, N. Kitwiroon, S. Beevers, P. Büker, and S. Cinderby
Atmos. Chem. Phys., 13, 6741–6755, https://doi.org/10.5194/acp-13-6741-2013, https://doi.org/10.5194/acp-13-6741-2013, 2013
C. A. Skjøth and C. Geels
Atmos. Chem. Phys., 13, 117–128, https://doi.org/10.5194/acp-13-117-2013, https://doi.org/10.5194/acp-13-117-2013, 2013
T. Kaminski, P. J. Rayner, M. Voßbeck, M. Scholze, and E. Koffi
Atmos. Chem. Phys., 12, 7867–7879, https://doi.org/10.5194/acp-12-7867-2012, https://doi.org/10.5194/acp-12-7867-2012, 2012
N. C. Parazoo, A. S. Denning, S. R. Kawa, S. Pawson, and R. Lokupitiya
Atmos. Chem. Phys., 12, 6405–6416, https://doi.org/10.5194/acp-12-6405-2012, https://doi.org/10.5194/acp-12-6405-2012, 2012
P. Büker, T. Morrissey, A. Briolat, R. Falk, D. Simpson, J.-P. Tuovinen, R. Alonso, S. Barth, M. Baumgarten, N. Grulke, P. E. Karlsson, J. King, F. Lagergren, R. Matyssek, A. Nunn, R. Ogaya, J. Peñuelas, L. Rhea, M. Schaub, J. Uddling, W. Werner, and L. D. Emberson
Atmos. Chem. Phys., 12, 5537–5562, https://doi.org/10.5194/acp-12-5537-2012, https://doi.org/10.5194/acp-12-5537-2012, 2012
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Short summary
The development of eddy-covariance measurements of ecosystem CO2 fluxes began a new era in the field studies of photosynthesis. The interpretation of the very variable CO2 fluxes in evergreen forests has been problematic especially in seasonal transition times. We apply two theoretical needle-level equations and show they can predict photosynthetic CO2 flux between the atmosphere and Scots pine forests. This has strong implications for the interpretation of the global change and boreal forests.
The development of eddy-covariance measurements of ecosystem CO2 fluxes began a new era in the...
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