Articles | Volume 21, issue 3
https://doi.org/10.5194/acp-21-1683-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-21-1683-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
09 Feb 2021
Research article |
| 09 Feb 2021
Observations on aerosol optical properties and scavenging during cloud events
Antti Ruuskanen
CORRESPONDING AUTHOR
Finnish Meteorological Institute, P.O. Box 1627, 70211 Kuopio, Finland
Sami Romakkaniemi
Finnish Meteorological Institute, P.O. Box 1627, 70211 Kuopio, Finland
Harri Kokkola
Finnish Meteorological Institute, P.O. Box 1627, 70211 Kuopio, Finland
Antti Arola
Finnish Meteorological Institute, P.O. Box 1627, 70211 Kuopio, Finland
Santtu Mikkonen
Department of Applied Physics, University of Eastern Finland, P.O. Box
1627, 70211 Kuopio, Finland
Department of Environmental and Biological Sciences, University of
Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
Harri Portin
Finnish Meteorological Institute, P.O. Box 1627, 70211 Kuopio, Finland
current address: Helsinki Region Environmental Services Authority, P.O. Box 100,
00066 HSY, Finland
Annele Virtanen
Department of Applied Physics, University of Eastern Finland, P.O. Box
1627, 70211 Kuopio, Finland
Kari E. J. Lehtinen
Finnish Meteorological Institute, P.O. Box 1627, 70211 Kuopio, Finland
Department of Applied Physics, University of Eastern Finland, P.O. Box
1627, 70211 Kuopio, Finland
Mika Komppula
Finnish Meteorological Institute, P.O. Box 1627, 70211 Kuopio, Finland
Ari Leskinen
Finnish Meteorological Institute, P.O. Box 1627, 70211 Kuopio, Finland
Department of Applied Physics, University of Eastern Finland, P.O. Box
1627, 70211 Kuopio, Finland
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Petri Tiitta, Ari Leskinen, Ville A. Kaikkonen, Eero O. Molkoselkä, Anssi J. Mäkynen, Jorma Joutsensaari, Silvia Calderon, Sami Romakkaniemi, and Mika Komppula
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Xiaoxia Shang, Holger Baars, Iwona S. Stachlewska, Ina Mattis, and Mika Komppula
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Tomi Raatikainen, Marje Prank, Jaakko Ahola, Harri Kokkola, Juha Tonttila, and Sami Romakkaniemi
Atmos. Chem. Phys., 22, 3763–3778, https://doi.org/10.5194/acp-22-3763-2022, https://doi.org/10.5194/acp-22-3763-2022, 2022
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Jessica Slater, Hugh Coe, Gordon McFiggans, Juha Tonttila, and Sami Romakkaniemi
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Antti Lipponen, Jaakko Reinvall, Arttu Väisänen, Henri Taskinen, Timo Lähivaara, Larisa Sogacheva, Pekka Kolmonen, Kari Lehtinen, Antti Arola, and Ville Kolehmainen
Atmos. Meas. Tech., 15, 895–914, https://doi.org/10.5194/amt-15-895-2022, https://doi.org/10.5194/amt-15-895-2022, 2022
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Kimmo Korhonen, Thomas Bjerring Kristensen, John Falk, Vilhelm B. Malmborg, Axel Eriksson, Louise Gren, Maja Novakovic, Sam Shamun, Panu Karjalainen, Lassi Markkula, Joakim Pagels, Birgitta Svenningsson, Martin Tunér, Mika Komppula, Ari Laaksonen, and Annele Virtanen
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Noora Hyttinen, Iida Pullinen, Aki Nissinen, Siegfried Schobesberger, Annele Virtanen, and Taina Yli-Juuti
Atmos. Chem. Phys., 22, 1195–1208, https://doi.org/10.5194/acp-22-1195-2022, https://doi.org/10.5194/acp-22-1195-2022, 2022
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Jutta Kesti, John Backman, Ewan J. O'Connor, Anne Hirsikko, Eija Asmi, Minna Aurela, Ulla Makkonen, Maria Filioglou, Mika Komppula, Hannele Korhonen, and Heikki Lihavainen
Atmos. Chem. Phys., 22, 481–503, https://doi.org/10.5194/acp-22-481-2022, https://doi.org/10.5194/acp-22-481-2022, 2022
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Ian Boutle, Wayne Angevine, Jian-Wen Bao, Thierry Bergot, Ritthik Bhattacharya, Andreas Bott, Leo Ducongé, Richard Forbes, Tobias Goecke, Evelyn Grell, Adrian Hill, Adele L. Igel, Innocent Kudzotsa, Christine Lac, Bjorn Maronga, Sami Romakkaniemi, Juerg Schmidli, Johannes Schwenkel, Gert-Jan Steeneveld, and Benoît Vié
Atmos. Chem. Phys., 22, 319–333, https://doi.org/10.5194/acp-22-319-2022, https://doi.org/10.5194/acp-22-319-2022, 2022
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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.
Anton Laakso, Ulrike Niemeier, Daniele Visioni, Simone Tilmes, and Harri Kokkola
Atmos. Chem. Phys., 22, 93–118, https://doi.org/10.5194/acp-22-93-2022, https://doi.org/10.5194/acp-22-93-2022, 2022
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The use of different spatio-temporal sulfur injection strategies with different magnitudes to create an artificial reflective aerosol layer to cool the climate is studied using sectional and modal aerosol schemes in a climate model. There are significant differences in the results depending on the aerosol microphysical module used. Different spatio-temporal injection strategies have a significant impact on the magnitude and zonal distribution of radiative forcing and atmospheric dynamics.
Zijun Li, Angela Buchholz, Arttu Ylisirniö, Luis Barreira, Liqing Hao, Siegfried Schobesberger, Taina Yli-Juuti, and Annele Virtanen
Atmos. Chem. Phys., 21, 18283–18302, https://doi.org/10.5194/acp-21-18283-2021, https://doi.org/10.5194/acp-21-18283-2021, 2021
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We compared the evolution of two types of secondary organic aerosol (SOA) particles during isothermal evaporation. The sesquiterpene SOA particles demonstrated higher resilience to evaporation than α-pinene SOA particles generated under comparable conditions. In-depth analysis showed that under high-relative-humidity conditions, particulate water drove the evolution of particulate constituents by reducing the particle viscosity and initiating chemical aqueous-phase processes.
Maria Sand, Bjørn H. Samset, Gunnar Myhre, Jonas Gliß, Susanne E. Bauer, Huisheng Bian, Mian Chin, Ramiro Checa-Garcia, Paul Ginoux, Zak Kipling, Alf Kirkevåg, Harri Kokkola, Philippe Le Sager, Marianne T. Lund, Hitoshi Matsui, Twan van Noije, Dirk J. L. Olivié, Samuel Remy, Michael Schulz, Philip Stier, Camilla W. Stjern, Toshihiko Takemura, Kostas Tsigaridis, Svetlana G. Tsyro, and Duncan Watson-Parris
Atmos. Chem. Phys., 21, 15929–15947, https://doi.org/10.5194/acp-21-15929-2021, https://doi.org/10.5194/acp-21-15929-2021, 2021
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Absorption of shortwave radiation by aerosols can modify precipitation and clouds but is poorly constrained in models. A total of 15 different aerosol models from AeroCom phase III have reported total aerosol absorption, and for the first time, 11 of these models have reported in a consistent experiment the contributions to absorption from black carbon, dust, and organic aerosol. Here, we document the model diversity in aerosol absorption.
Anu Kauppi, Antti Kukkurainen, Antti Lipponen, Marko Laine, Antti Arola, Hannakaisa Lindqvist, and Johanna Tamminen
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2021-328, https://doi.org/10.5194/amt-2021-328, 2021
Revised manuscript not accepted
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We present a methodology in Bayesian framework for retrieving atmospheric aerosol optical depth and aerosol type from the pre-computed look-up tables (LUTs). Especially, we consider Bayesian model averaging and uncertainty originating from aerosol model selection and imperfect forward modelling. Our aim is to get more realistic uncertainty estimates. We have applied the methodology to TROPOMI/S5P satellite observations and evaluated the results against ground-based data from the AERONET.
Xiaoxia Shang, Tero Mielonen, Antti Lipponen, Elina Giannakaki, Ari Leskinen, Virginie Buchard, Anton S. Darmenov, Antti Kukkurainen, Antti Arola, Ewan O'Connor, Anne Hirsikko, and Mika Komppula
Atmos. Meas. Tech., 14, 6159–6179, https://doi.org/10.5194/amt-14-6159-2021, https://doi.org/10.5194/amt-14-6159-2021, 2021
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The long-range-transported smoke particles from a Canadian wildfire event were observed with a multi-wavelength Raman polarization lidar and a ceilometer over Kuopio, Finland, in June 2019. The optical properties and the mass concentration estimations were reported for such aged smoke aerosols over northern Europe.
Kevin Lamy, Thierry Portafaix, Colette Brogniez, Kaisa Lakkala, Mikko R. A. Pitkänen, Antti Arola, Jean-Baptiste Forestier, Vincent Amelie, Mohamed Abdoulwahab Toihir, and Solofoarisoa Rakotoniaina
Earth Syst. Sci. Data, 13, 4275–4301, https://doi.org/10.5194/essd-13-4275-2021, https://doi.org/10.5194/essd-13-4275-2021, 2021
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This paper is about the presentation of the UV-Indien measurement network. This network measures the ultraviolet radiation emitted by the Sun received at the Earth's surface and the clouding above each station. It has been deployed at several sites in the Indian Ocean region representing different environmental conditions. A description of the instruments and their calibration, maintenance, and data processing is presented in this paper along with a valuation of the data quality.
Matthew Ozon, Dominik Stolzenburg, Lubna Dada, Aku Seppänen, and Kari E. J. Lehtinen
Atmos. Chem. Phys., 21, 12595–12611, https://doi.org/10.5194/acp-21-12595-2021, https://doi.org/10.5194/acp-21-12595-2021, 2021
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Measuring the rate at which aerosol particles are formed is of importance for understanding climate change. We present an analysis method based on Kalman smoothing, which retrieves new particle formation and growth rates from size-distribution measurements. We apply it to atmospheric simulation chamber experiments and show that it agrees well with traditional methods. In addition, it provides reliable uncertainty estimates, and we suggest instrument design optimisation for signal processing.
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.
Ana A. Piedehierro, André Welti, Angela Buchholz, Kimmo Korhonen, Iida Pullinen, Ilkka Summanen, Annele Virtanen, and Ari Laaksonen
Atmos. Chem. Phys., 21, 11069–11078, https://doi.org/10.5194/acp-21-11069-2021, https://doi.org/10.5194/acp-21-11069-2021, 2021
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Ice crystals in cirrus clouds contain particles that start ice formation. We study whether particles forming above boreal forests can help in the making of cirrus clouds and if the water content in the particles affects this property. In the laboratory, we made boreal-forest-like particles and cooled and humidified them to measure whether an ice crystal develops. We found that only when dry can these particles form an ice crystal but no better than solution droplets.
Antti Arola, William Wandji Nyamsi, Antti Lipponen, Stelios Kazadzis, Nickolay A. Krotkov, and Johanna Tamminen
Atmos. Meas. Tech., 14, 4947–4957, https://doi.org/10.5194/amt-14-4947-2021, https://doi.org/10.5194/amt-14-4947-2021, 2021
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Methods to estimate surface UV radiation from satellite measurements offer the only means to obtain global coverage, and the development of satellite-based UV algorithms has been ongoing since the early 1990s. One of the main challenges in this development has been how to account for the overall effect of absorption by atmospheric aerosols. One such method was suggested roughly a decade ago, and in this study we propose further improvements for this kind of approach.
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.
Matthew Ozon, Aku Seppänen, Jari P. Kaipio, and Kari E. J. Lehtinen
Geosci. Model Dev., 14, 3715–3739, https://doi.org/10.5194/gmd-14-3715-2021, https://doi.org/10.5194/gmd-14-3715-2021, 2021
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Experimental research has provided large amounts of high-quality data on aerosol over the last 2 decades. However, inference of the process rates (e.g., the rates at which particles are generated) is still typically done by simple curve-fitting methods and does not assess the credibility of the estimation. The devised method takes advantage of the Bayesian framework to not only retrieve the state of the observed aerosol system but also to estimate the process rates (e.g., growth rate).
Stephanie Bohlmann, Xiaoxia Shang, Ville Vakkari, Elina Giannakaki, Ari Leskinen, Kari E. J. Lehtinen, Sanna Pätsi, and Mika Komppula
Atmos. Chem. Phys., 21, 7083–7097, https://doi.org/10.5194/acp-21-7083-2021, https://doi.org/10.5194/acp-21-7083-2021, 2021
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Measurements of the multi-wavelength Raman polarization lidar PollyXT and a Halo Photonics StreamLine Doppler lidar have been combined with measurements of pollen type and concentration using a traditional pollen trap at the rural forest site in Vehmasmäki, Finland. Depolarization ratios were measured at three wavelengths. High depolarization ratios were detected during an event with high birch and spruce pollen concentrations and a wavelength dependence of the depolarization ratio was observed.
Luis M. F. Barreira, Aku Helin, Minna Aurela, Kimmo Teinilä, Milla Friman, Leena Kangas, Jarkko V. Niemi, Harri Portin, Anu Kousa, Liisa Pirjola, Topi Rönkkö, Sanna Saarikoski, and Hilkka Timonen
Atmos. Chem. Phys., 21, 6297–6314, https://doi.org/10.5194/acp-21-6297-2021, https://doi.org/10.5194/acp-21-6297-2021, 2021
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We present results from the long-term measurements (5 years) of highly time-resolved atmospheric PM1 composition at an urban street canyon site. Overall, the results increased knowledge of the variability of PM1 concentration, composition, and sources in a traffic site and the implications for urban air quality. The investigation of pollution episodes showed that both local and long-range-transported pollutants can still cause elevated PM1 and PM2.5 concentrations in northern Europe.
Antti Lipponen, Ville Kolehmainen, Pekka Kolmonen, Antti Kukkurainen, Tero Mielonen, Neus Sabater, Larisa Sogacheva, Timo H. Virtanen, and Antti Arola
Atmos. Meas. Tech., 14, 2981–2992, https://doi.org/10.5194/amt-14-2981-2021, https://doi.org/10.5194/amt-14-2981-2021, 2021
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We have developed a new computational method to post-process-correct the satellite aerosol retrievals. The proposed method combines the conventional satellite aerosol retrievals relying on physics-based models and machine learning. The results show significantly improved accuracy in the aerosol data over the operational satellite data products. The correction can be applied to the existing satellite aerosol datasets with no need to fully reprocess the much larger original radiance data.
Ville Vakkari, Holger Baars, Stephanie Bohlmann, Johannes Bühl, Mika Komppula, Rodanthi-Elisavet Mamouri, and Ewan James O'Connor
Atmos. Chem. Phys., 21, 5807–5820, https://doi.org/10.5194/acp-21-5807-2021, https://doi.org/10.5194/acp-21-5807-2021, 2021
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The depolarization ratio is a valuable parameter for aerosol categorization from remote sensing measurements. Here, we introduce particle depolarization ratio measurements at the 1565 nm wavelength, which is substantially longer than previously utilized wavelengths and enhances our capabilities to study the wavelength dependency of the particle depolarization ratio.
Nicola Zoppetti, Simone Ceccherini, Bruno Carli, Samuele Del Bianco, Marco Gai, Cecilia Tirelli, Flavio Barbara, Rossana Dragani, Antti Arola, Jukka Kujanpää, Jacob C. A. van Peet, Ronald van der A, and Ugo Cortesi
Atmos. Meas. Tech., 14, 2041–2053, https://doi.org/10.5194/amt-14-2041-2021, https://doi.org/10.5194/amt-14-2041-2021, 2021
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The new platforms for Earth observation from space will provide an enormous amount of data that can be hard to exploit as a whole. The Complete Data Fusion algorithm can reduce the data volume while retaining the information of the full dataset. In this work, we applied the Complete Data Fusion algorithm to simulated ozone profiles, and the results show that the fused products are characterized by higher information content compared to individual L2 products.
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.
Maria Mylonaki, Elina Giannakaki, Alexandros Papayannis, Christina-Anna Papanikolaou, Mika Komppula, Doina Nicolae, Nikolaos Papagiannopoulos, Aldo Amodeo, Holger Baars, and Ourania Soupiona
Atmos. Chem. Phys., 21, 2211–2227, https://doi.org/10.5194/acp-21-2211-2021, https://doi.org/10.5194/acp-21-2211-2021, 2021
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We introduce an automated aerosol type classification method, SCAN. The output of SCAN is compared with two aerosol classification methods: (1) the Mahalanobis distance automatic aerosol type classification and (2) a neural network aerosol typing algorithm. A total of 97 free tropospheric aerosol layers from four EARLINET stations in the period 2014–2018 were classified.
Juha Tonttila, Ali Afzalifar, Harri Kokkola, Tomi Raatikainen, Hannele Korhonen, and Sami Romakkaniemi
Atmos. Chem. Phys., 21, 1035–1048, https://doi.org/10.5194/acp-21-1035-2021, https://doi.org/10.5194/acp-21-1035-2021, 2021
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The focus of this study is on rain enhancement by deliberate injection of small particles into clouds (
cloud seeding). The particles, usually released from an aircraft, are expected to enhance cloud droplet growth, but its practical feasibility is somewhat uncertain. To improve upon this, we simulate the seeding effects with a numerical model. The model reproduces the main features seen in field observations, with a strong sensitivity to the total mass of the injected particle material.
Arttu Ylisirniö, Luis M. F. Barreira, Iida Pullinen, Angela Buchholz, John Jayne, Jordan E. Krechmer, Douglas R. Worsnop, Annele Virtanen, and Siegfried Schobesberger
Atmos. Meas. Tech., 14, 355–367, https://doi.org/10.5194/amt-14-355-2021, https://doi.org/10.5194/amt-14-355-2021, 2021
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FIGAERO-ToF-CIMS enables online volatility measurements of chemical compounds in ambient aerosols. Previously published volatility calibration results however differ from each other significantly. In this study we investigate the reason for this discrepancy. We found a major source of error in the widely used syringe deposition method and propose a new method for volatility calibration by using atomized calibration compounds.
Jonas Gliß, Augustin Mortier, Michael Schulz, Elisabeth Andrews, Yves Balkanski, Susanne E. Bauer, Anna M. K. Benedictow, Huisheng Bian, Ramiro Checa-Garcia, Mian Chin, Paul Ginoux, Jan J. Griesfeller, Andreas Heckel, Zak Kipling, Alf Kirkevåg, Harri Kokkola, Paolo Laj, Philippe Le Sager, Marianne Tronstad Lund, Cathrine Lund Myhre, Hitoshi Matsui, Gunnar Myhre, David Neubauer, Twan van Noije, Peter North, Dirk J. L. Olivié, Samuel Rémy, Larisa Sogacheva, Toshihiko Takemura, Kostas Tsigaridis, and Svetlana G. Tsyro
Atmos. Chem. Phys., 21, 87–128, https://doi.org/10.5194/acp-21-87-2021, https://doi.org/10.5194/acp-21-87-2021, 2021
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Simulated aerosol optical properties as well as the aerosol life cycle are investigated for 14 global models participating in the AeroCom initiative. Considerable diversity is found in the simulated aerosol species emissions and lifetimes, also resulting in a large diversity in the simulated aerosol mass, composition, and optical properties. A comparison with observations suggests that, on average, current models underestimate the direct effect of aerosol on the atmosphere radiation budget.
André Welti, Kimmo Korhonen, Pasi Miettinen, Ana A. Piedehierro, Yrjö Viisanen, Annele Virtanen, and Ari Laaksonen
Atmos. Meas. Tech., 13, 7059–7067, https://doi.org/10.5194/amt-13-7059-2020, https://doi.org/10.5194/amt-13-7059-2020, 2020
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We describe a modification of the SPectrometer for Ice Nuclei (SPIN) chamber to study ice nucleation at low temperatures, relevant for ice formation in cirrus clouds. Validation experiments of homogeneous freezing of aqueous ammonium sulfate droplets and heterogeneous ice nucleation on silver iodide particles are included to demonstrate the advantages of the modified SPIN chamber for the investigation of ice nucleation in the extended temperature range.
Kaisa Lakkala, Jukka Kujanpää, Colette Brogniez, Nicolas Henriot, Antti Arola, Margit Aun, Frédérique Auriol, Alkiviadis F. Bais, Germar Bernhard, Veerle De Bock, Maxime Catalfamo, Christine Deroo, Henri Diémoz, Luca Egli, Jean-Baptiste Forestier, Ilias Fountoulakis, Katerina Garane, Rosa Delia Garcia, Julian Gröbner, Seppo Hassinen, Anu Heikkilä, Stuart Henderson, Gregor Hülsen, Bjørn Johnsen, Niilo Kalakoski, Angelos Karanikolas, Tomi Karppinen, Kevin Lamy, Sergio F. León-Luis, Anders V. Lindfors, Jean-Marc Metzger, Fanny Minvielle, Harel B. Muskatel, Thierry Portafaix, Alberto Redondas, Ricardo Sanchez, Anna Maria Siani, Tove Svendby, and Johanna Tamminen
Atmos. Meas. Tech., 13, 6999–7024, https://doi.org/10.5194/amt-13-6999-2020, https://doi.org/10.5194/amt-13-6999-2020, 2020
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The TROPOspheric Monitoring Instrument (TROPOMI) onboard the Sentinel-5 Precursor (S5P) satellite was launched on 13 October 2017 to provide the atmospheric composition for atmosphere and climate research. Ground-based data from 25 sites located in Arctic, subarctic, temperate, equatorial and Antarctic
areas were used for the validation of the TROPOMI surface ultraviolet (UV) radiation product. For most sites 60 %–80 % of TROPOMI data was within ± 20 % of ground-based data.
Xiaoxia Shang, Elina Giannakaki, Stephanie Bohlmann, Maria Filioglou, Annika Saarto, Antti Ruuskanen, Ari Leskinen, Sami Romakkaniemi, and Mika Komppula
Atmos. Chem. Phys., 20, 15323–15339, https://doi.org/10.5194/acp-20-15323-2020, https://doi.org/10.5194/acp-20-15323-2020, 2020
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Measurements of the multi-wavelength Raman polarization lidar PollyXT have been combined with measurements of pollen type and concentration using a traditional pollen sampler at a rural forest site in Kuopio, Finland. The depolarization ratio was enhanced when there were pollen grains in the atmosphere, illustrating the potential of lidar to track pollen grains in the atmosphere. The depolarization ratio of pure pollen particles was assessed for birch and pine pollen using a novel algorithm.
Eemeli Holopainen, Harri Kokkola, Anton Laakso, and Thomas Kühn
Geosci. Model Dev., 13, 6215–6235, https://doi.org/10.5194/gmd-13-6215-2020, https://doi.org/10.5194/gmd-13-6215-2020, 2020
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This paper introduces an in-cloud wet deposition scheme for liquid and ice phase clouds for global aerosol–climate models. With the default setup, our wet deposition scheme behaves spuriously and better representation can be achieved with this scheme when black carbon is mixed with soluble compounds at emission time. This work is done as many of the global models fail to reproduce the transport of black carbon to the Arctic, which may be due to the poor representation of wet removal in models.
Johannes Quaas, Antti Arola, Brian Cairns, Matthew Christensen, Hartwig Deneke, Annica M. L. Ekman, Graham Feingold, Ann Fridlind, Edward Gryspeerdt, Otto Hasekamp, Zhanqing Li, Antti Lipponen, Po-Lun Ma, Johannes Mülmenstädt, Athanasios Nenes, Joyce E. Penner, Daniel Rosenfeld, Roland Schrödner, Kenneth Sinclair, Odran Sourdeval, Philip Stier, Matthias Tesche, Bastiaan van Diedenhoven, and Manfred Wendisch
Atmos. Chem. Phys., 20, 15079–15099, https://doi.org/10.5194/acp-20-15079-2020, https://doi.org/10.5194/acp-20-15079-2020, 2020
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Anthropogenic pollution particles – aerosols – serve as cloud condensation nuclei and thus increase cloud droplet concentration and the clouds' reflection of sunlight (a cooling effect on climate). This Twomey effect is poorly constrained by models and requires satellite data for better quantification. The review summarizes the challenges in properly doing so and outlines avenues for progress towards a better use of aerosol retrievals and better retrievals of droplet concentrations.
Liqing Hao, Eetu Kari, Ari Leskinen, Douglas R. Worsnop, and Annele Virtanen
Atmos. Chem. Phys., 20, 14393–14405, https://doi.org/10.5194/acp-20-14393-2020, https://doi.org/10.5194/acp-20-14393-2020, 2020
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Our work presents the observational results of secondary organic aerosol (SOA) formation in the presence of ammonia. The particle-phase ammonium was continuously produced even after SOA formation had ceased. The gas-phase organic acids were observed to contribute to the formed particle-phase ammonium salts. This study suggests that the presence of ammonia may change the mass and chemical composition of large-size SOA particles and can potentially alter the aerosol impact on climate change.
Santtu Mikkonen, Zoltán Németh, Veronika Varga, Tamás Weidinger, Ville Leinonen, Taina Yli-Juuti, and Imre Salma
Atmos. Chem. Phys., 20, 12247–12263, https://doi.org/10.5194/acp-20-12247-2020, https://doi.org/10.5194/acp-20-12247-2020, 2020
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We determined decennial statistical time trends and diurnal statistical patterns of atmospheric particle number concentrations in various relevant size fractions in the city centre of Budapest in an interval of 2008–2018. The mean overall decrease rate of particles in different size fractions was approximately −5 % scaled for the 10-year measurement interval. The decline can be interpreted as a consequence of the decreased anthropogenic emissions in the city.
Jessica Slater, Juha Tonttila, Gordon McFiggans, Paul Connolly, Sami Romakkaniemi, Thomas Kühn, and Hugh Coe
Atmos. Chem. Phys., 20, 11893–11906, https://doi.org/10.5194/acp-20-11893-2020, https://doi.org/10.5194/acp-20-11893-2020, 2020
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The feedback effect between aerosol particles, radiation and meteorology reduces turbulent motion and results in increased surface aerosol concentrations during Beijing haze. Observational analysis and regional modelling studies have examined the feedback effect but these studies are limited. In this work, we set up a high-resolution model for the Beijing environment to examine the sensitivity of the aerosol feedback effect to initial meteorological conditions and aerosol loading.
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.
Jaakko Ahola, Hannele Korhonen, Juha Tonttila, Sami Romakkaniemi, Harri Kokkola, and Tomi Raatikainen
Atmos. Chem. Phys., 20, 11639–11654, https://doi.org/10.5194/acp-20-11639-2020, https://doi.org/10.5194/acp-20-11639-2020, 2020
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In this study, we present an improved cloud model that reproduces the behaviour of mixed-phase clouds containing liquid droplets and ice crystals in more detail than before. This model is a convenient computational tool that enables the study of phenomena that cannot fit into a laboratory. These clouds have a significant role in climate, but they are not yet properly understood. Here, we show the advantages of the new model in a case study focusing on Arctic mixed-phase clouds.
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.
Innocent Kudzotsa, Harri Kokkola, Juha Tonttila, Tomi Raatikainen, and Sami Romakkaniemi
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-851, https://doi.org/10.5194/acp-2020-851, 2020
Publication in ACP not foreseen
Olli-Pekka Tikkanen, Angela Buchholz, Arttu Ylisirniö, Siegfried Schobesberger, Annele Virtanen, and Taina Yli-Juuti
Atmos. Chem. Phys., 20, 10441–10458, https://doi.org/10.5194/acp-20-10441-2020, https://doi.org/10.5194/acp-20-10441-2020, 2020
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We compared the volatility distributions of secondary organic aerosol (SOA) constituents estimated from isothermal evaporation experiments from either particle size change data, by process modelling and global optimization, or from mass spectrometer data with positive matrix factorization analysis. Our results show that, despite the two very different estimation methods, the volatility distributions are comparable if uncertainties are taken into account.
María A. Burgos, Elisabeth Andrews, Gloria Titos, Angela Benedetti, Huisheng Bian, Virginie Buchard, Gabriele Curci, Zak Kipling, Alf Kirkevåg, Harri Kokkola, Anton Laakso, Julie Letertre-Danczak, Marianne T. Lund, Hitoshi Matsui, Gunnar Myhre, Cynthia Randles, Michael Schulz, Twan van Noije, Kai Zhang, Lucas Alados-Arboledas, Urs Baltensperger, Anne Jefferson, James Sherman, Junying Sun, Ernest Weingartner, and Paul Zieger
Atmos. Chem. Phys., 20, 10231–10258, https://doi.org/10.5194/acp-20-10231-2020, https://doi.org/10.5194/acp-20-10231-2020, 2020
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We investigate how well models represent the enhancement in scattering coefficients due to particle water uptake, and perform an evaluation of several implementation schemes used in ten Earth system models. Our results show the importance of the parameterization of hygroscopicity and model chemistry as drivers of some of the observed diversity amongst model estimates. The definition of dry conditions and the phenomena taking place in this relative humidity range also impact the model evaluation.
Maria Filioglou, Elina Giannakaki, John Backman, Jutta Kesti, Anne Hirsikko, Ronny Engelmann, Ewan O'Connor, Jari T. T. Leskinen, Xiaoxia Shang, Hannele Korhonen, Heikki Lihavainen, Sami Romakkaniemi, and Mika Komppula
Atmos. Chem. Phys., 20, 8909–8922, https://doi.org/10.5194/acp-20-8909-2020, https://doi.org/10.5194/acp-20-8909-2020, 2020
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Dust optical properties are region-dependent. Saharan, Asian, and Arabian dusts do not pose similar optical properties in terms of lidar ratios; thus, a universal lidar ratio for dust particles will lead to biases. The present study analyses observations over the United Arab Emirates, quantifying the optical and geometrical extents of the aerosol layers in the area, providing at the same time the Arabian dust properties along with chemical analysis of dust samples collected in the region.
Angela Buchholz, Arttu Ylisirniö, Wei Huang, Claudia Mohr, Manjula Canagaratna, Douglas R. Worsnop, Siegfried Schobesberger, and Annele Virtanen
Atmos. Chem. Phys., 20, 7693–7716, https://doi.org/10.5194/acp-20-7693-2020, https://doi.org/10.5194/acp-20-7693-2020, 2020
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To understand the role of aerosol particles in the atmosphere, it is necessary to know their detailed chemical composition and physical properties, especially volatility. The thermal desorption data from FIGAERO–CIMS provides both but are difficult to analyse. With positive matrix factorisation, we can separate instrument background from the real signal. Compounds can be classified by their apparent volatility, and the contribution of thermal decomposition in the instrument can be identified.
William Wandji Nyamsi, Antti Lipponen, Arturo Sanchez-Lorenzo, Martin Wild, and Antti Arola
Atmos. Meas. Tech., 13, 3061–3079, https://doi.org/10.5194/amt-13-3061-2020, https://doi.org/10.5194/amt-13-3061-2020, 2020
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This paper proposes a novel and accurate method for estimating and reconstructing aerosol optical depth from sunshine duration measurements under cloud-free conditions at any place and time since the late 19th century. The method performs very well when compared to AErosol RObotic NETwork measurements and operates an efficient detection of signals from massive volcanic eruptions. Reconstructed long-term aerosol optical depths are in agreement with the dimming/brightening phenomenon.
Sini Isokääntä, Eetu Kari, Angela Buchholz, Liqing Hao, Siegfried Schobesberger, Annele Virtanen, and Santtu Mikkonen
Atmos. Meas. Tech., 13, 2995–3022, https://doi.org/10.5194/amt-13-2995-2020, https://doi.org/10.5194/amt-13-2995-2020, 2020
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Online mass spectrometry produces large amounts of data. These data can be interpreted with statistical methods, enabling scientists to more easily understand the underlying processes. We compared these techniques on car exhaust measurements. We show differences and similarities between the methods and give recommendations on applicability of the methods on certain types of data. We show that applying multiple methods leads to more robust results, thus increasing reliability of the findings.
Margit Aun, Kaisa Lakkala, Ricardo Sanchez, Eija Asmi, Fernando Nollas, Outi Meinander, Larisa Sogacheva, Veerle De Bock, Antti Arola, Gerrit de Leeuw, Veijo Aaltonen, David Bolsée, Klara Cizkova, Alexander Mangold, Ladislav Metelka, Erko Jakobson, Tove Svendby, Didier Gillotay, and Bert Van Opstal
Atmos. Chem. Phys., 20, 6037–6054, https://doi.org/10.5194/acp-20-6037-2020, https://doi.org/10.5194/acp-20-6037-2020, 2020
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In 2017, new measurements of UV radiation started in Marambio, Antarctica, by the Finnish Meteorological Institute in collaboration with the Argentinian Servicio Meteorológico Nacional. The paper presents the results of UV irradiance measurements from March 2017 to March 2019, and it
compares them with those from 2000–2008 and also with UV measurements at other Antarctic stations. In 2017/2018, below average UV radiation levels were recorded due to favourable ozone and cloud conditions.
Arttu Ylisirniö, Angela Buchholz, Claudia Mohr, Zijun Li, Luis Barreira, Andrew Lambe, Celia Faiola, Eetu Kari, Taina Yli-Juuti, Sergey A. Nizkorodov, Douglas R. Worsnop, Annele Virtanen, and Siegfried Schobesberger
Atmos. Chem. Phys., 20, 5629–5644, https://doi.org/10.5194/acp-20-5629-2020, https://doi.org/10.5194/acp-20-5629-2020, 2020
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We studied the chemical composition and volatility of secondary organic aerosol (SOA) particles formed from emissions of Scots pines and compared those results to SOA formed from α-pinene and from a sesquiterpene mixture. We found that SOA formed from single precursors cannot capture the properties of SOA formed from real plant emissions.
Thomas Kühn, Kaarle Kupiainen, Tuuli Miinalainen, Harri Kokkola, Ville-Veikko Paunu, Anton Laakso, Juha Tonttila, Rita Van Dingenen, Kati Kulovesi, Niko Karvosenoja, and Kari E. J. Lehtinen
Atmos. Chem. Phys., 20, 5527–5546, https://doi.org/10.5194/acp-20-5527-2020, https://doi.org/10.5194/acp-20-5527-2020, 2020
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We investigate the effects of black carbon (BC) mitigation on Arctic climate and human health, accounting for the concurrent reduction of other aerosol species. While BC is attributed a net warming effect on climate, most other aerosol species cool the planet. We find that the direct radiative effect of mitigating BC induces cooling, while aerosol–cloud effects offset this cooling and introduce large uncertainties. Furthermore, the reduced aerosol emissions reduce human mortality considerably.
Kaisa Lakkala, Margit Aun, Ricardo Sanchez, Germar Bernhard, Eija Asmi, Outi Meinander, Fernando Nollas, Gregor Hülsen, Tomi Karppinen, Veijo Aaltonen, Antti Arola, and Gerrit de Leeuw
Earth Syst. Sci. Data, 12, 947–960, https://doi.org/10.5194/essd-12-947-2020, https://doi.org/10.5194/essd-12-947-2020, 2020
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A GUV multi-filter radiometer was set up at Marambio, 64° S, 56° W, Antarctica, in 2017. The instrument continuously measures ultraviolet (UV) radiation, visible (VIS) radiation and photosynthetically active radiation (PAR). The measurements are designed for providing high-quality long-term time series that can be used to assess the impact of global climate change in the Antarctic region. The data from the last 5 d are plotted and updated daily.
Kimmo Korhonen, Thomas Bjerring Kristensen, John Falk, Robert Lindgren, Christina Andersen, Ricardo Luis Carvalho, Vilhelm Malmborg, Axel Eriksson, Christoffer Boman, Joakim Pagels, Birgitta Svenningsson, Mika Komppula, Kari E. J. Lehtinen, and Annele Virtanen
Atmos. Chem. Phys., 20, 4951–4968, https://doi.org/10.5194/acp-20-4951-2020, https://doi.org/10.5194/acp-20-4951-2020, 2020
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Ice-nucleating abilities of particulate emissions from solid-fuel-burning cookstoves were studied using a portable ice nuclei counter in an extensive laboratory experiment campaign. We found that even small changes in combustion conditions may affect the ice-nucleating ability of the emissions significantly. Also six different physico-chemical properties of the emissions were studied, but no clear correlation to their ice-nucleating ability was found.
Kalliopi Artemis Voudouri, Elina Giannakaki, Mika Komppula, and Dimitris Balis
Atmos. Chem. Phys., 20, 4427–4444, https://doi.org/10.5194/acp-20-4427-2020, https://doi.org/10.5194/acp-20-4427-2020, 2020
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In this paper we present the variability in cirrus cloud properties using a PollyXT Raman lidar over high and tropical latitudes. The kind of information presented here can be rather useful in the cirrus parameterisations required as input to radiative transfer models and can be a complementary tool for satellite products that cannot provide cloud vertical structure.
Larisa Sogacheva, Thomas Popp, Andrew M. Sayer, Oleg Dubovik, Michael J. Garay, Andreas Heckel, N. Christina Hsu, Hiren Jethva, Ralph A. Kahn, Pekka Kolmonen, Miriam Kosmale, Gerrit de Leeuw, Robert C. Levy, Pavel Litvinov, Alexei Lyapustin, Peter North, Omar Torres, and Antti Arola
Atmos. Chem. Phys., 20, 2031–2056, https://doi.org/10.5194/acp-20-2031-2020, https://doi.org/10.5194/acp-20-2031-2020, 2020
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The typical lifetime of a single satellite platform is on the order of 5–15 years; thus, for climate studies the usage of multiple satellite sensors should be considered.
Here we introduce and evaluate a monthly AOD merged product and AOD global and regional time series for the period 1995–2017 created from 12 individual satellite AOD products, which provide a long-term perspective on AOD changes over different regions of the globe.
Elina Giannakaki, Panos Kokkalis, Eleni Marinou, Nikolaos S. Bartsotas, Vassilis Amiridis, Albert Ansmann, and Mika Komppula
Atmos. Meas. Tech., 13, 893–905, https://doi.org/10.5194/amt-13-893-2020, https://doi.org/10.5194/amt-13-893-2020, 2020
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A new method, called ElEx, is proposed for the estimation of extinction coefficient lidar profiles using only the information provided by the elastic and polarization channels of a lidar system. The method is applicable to lidar measurements both during daytime and nighttime under well-defined aerosol mixtures. Comparisons with both Raman lidar profiles during nightime and sun photometer daytime aerosol optical depth observations demonstrate the potential of the ElEx methodology.
Giulia Saponaro, Moa K. Sporre, David Neubauer, Harri Kokkola, Pekka Kolmonen, Larisa Sogacheva, Antti Arola, Gerrit de Leeuw, Inger H. H. Karset, Ari Laaksonen, and Ulrike Lohmann
Atmos. Chem. Phys., 20, 1607–1626, https://doi.org/10.5194/acp-20-1607-2020, https://doi.org/10.5194/acp-20-1607-2020, 2020
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The understanding of cloud processes is based on the quality of the representation of cloud properties. We compared cloud parameters from three models with satellite observations. We report on the performance of each data source, highlighting strengths and deficiencies, which should be considered when deriving the effect of aerosols on cloud properties.
Ville Leinonen, Petri Tiitta, Olli Sippula, Hendryk Czech, Ari Leskinen, Juha Karvanen, Sini Isokääntä, and Santtu Mikkonen
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2020-13, https://doi.org/10.5194/gmd-2020-13, 2020
Revised manuscript not accepted
Eetu Kari, Liqing Hao, Arttu Ylisirniö, Angela Buchholz, Ari Leskinen, Pasi Yli-Pirilä, Ilpo Nuutinen, Kari Kuuspalo, Jorma Jokiniemi, Celia L. Faiola, Siegfried Schobesberger, and Annele Virtanen
Atmos. Chem. Phys., 19, 15651–15671, https://doi.org/10.5194/acp-19-15651-2019, https://doi.org/10.5194/acp-19-15651-2019, 2019
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We present, for the first time, the dual effect of GDI-vehicle exhaust on α-pinene SOA mass yield suppression. The first effect is a well-known NOx effect, but the second effect is more complex. Our results imply that this second effect is related to change of reaction pathways of α-pinene in the presence of GDI exhaust. The presence of vehicle exhaust caused more than 50 % suppression in α-pinene SOA mass yield compared to the α-pinene SOA mass yield measured in the absence of GDI emissions.
Jianhui Jiang, Sebnem Aksoyoglu, Imad El-Haddad, Giancarlo Ciarelli, Hugo A. C. Denier van der Gon, Francesco Canonaco, Stefania Gilardoni, Marco Paglione, María Cruz Minguillón, Olivier Favez, Yunjiang Zhang, Nicolas Marchand, Liqing Hao, Annele Virtanen, Kalliopi Florou, Colin O'Dowd, Jurgita Ovadnevaite, Urs Baltensperger, and André S. H. Prévôt
Atmos. Chem. Phys., 19, 15247–15270, https://doi.org/10.5194/acp-19-15247-2019, https://doi.org/10.5194/acp-19-15247-2019, 2019
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We use an air quality model with a modified organic aerosol (OA) module based on chamber experiments to identify the OA sources and their contributions in Europe. Comparisons with long-term measurements at nine sites in 2011 show an improvement in OA simulation. Our results suggest that the biomass burning and biogenic emissions are the dominant sources in winter and summer, respectively. Contributions of diesel and gasoline vehicles are relatively small compared to a previous study in the US.
Stephanie Bohlmann, Xiaoxia Shang, Elina Giannakaki, Maria Filioglou, Annika Saarto, Sami Romakkaniemi, and Mika Komppula
Atmos. Chem. Phys., 19, 14559–14569, https://doi.org/10.5194/acp-19-14559-2019, https://doi.org/10.5194/acp-19-14559-2019, 2019
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Measurements of the multiwavelength Raman polarization lidar PollyXT have been combined with measurements of pollen type and concentration using a traditional pollen sampler at the rural forest site in Vehmasmäki, Finland. High particle depolarization ratios were observed during an intense pollination event of birch pollen occasionally mixed with spruce pollen. Our observations illustrate the potential of the particle depolarization ratio to track pollen grains in the atmosphere.
Santtu Mikkonen, Mikko R. A. Pitkänen, Tuomo Nieminen, Antti Lipponen, Sini Isokääntä, Antti Arola, and Kari E. J. Lehtinen
Atmos. Chem. Phys., 19, 12531–12543, https://doi.org/10.5194/acp-19-12531-2019, https://doi.org/10.5194/acp-19-12531-2019, 2019
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Atmospheric measurement data never come without measurement error. Too often, these errors are neglected when researchers make inferences from their data. We applied multiple line-fitting methods to simulated data mimicking two central variables in aerosol research. Our results show that an ordinary least squares fit, typically used to describe relationships, underestimates the slope of the fit and that methods taking the measurement uncertainty into account performed significantly better.
David Neubauer, Sylvaine Ferrachat, Colombe Siegenthaler-Le Drian, Philip Stier, Daniel G. Partridge, Ina Tegen, Isabelle Bey, Tanja Stanelle, Harri Kokkola, and Ulrike Lohmann
Geosci. Model Dev., 12, 3609–3639, https://doi.org/10.5194/gmd-12-3609-2019, https://doi.org/10.5194/gmd-12-3609-2019, 2019
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The global aerosol–climate model ECHAM6.3–HAM2.3 as well as the previous model versions ECHAM5.5–HAM2.0 and ECHAM6.1–HAM2.2 are evaluated. The simulation of clouds has improved in ECHAM6.3–HAM2.3. This has an impact on effective radiative forcing due to aerosol–radiation and aerosol–cloud interactions and equilibrium climate sensitivity, which are weaker in ECHAM6.3–HAM2.3 than in the previous model versions.
Olli-Pekka Tikkanen, Väinö Hämäläinen, Grazia Rovelli, Antti Lipponen, Manabu Shiraiwa, Jonathan P. Reid, Kari E. J. Lehtinen, and Taina Yli-Juuti
Atmos. Chem. Phys., 19, 9333–9350, https://doi.org/10.5194/acp-19-9333-2019, https://doi.org/10.5194/acp-19-9333-2019, 2019
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We assessed how well the organic aerosol particle composition and viscosity can be captured by optimizing process models to match particle evaporation data. We performed the analysis for both artificial and real evaporation data and tested two optimization algorithms. Our findings show that the optimization method yields a good estimate for the studied properties. The timescale of the evaporation data and particle size was found to be important in identifying the volatility of organic compounds.
Sieglinde Callewaert, Sophie Vandenbussche, Nicolas Kumps, Arve Kylling, Xiaoxia Shang, Mika Komppula, Philippe Goloub, and Martine De Mazière
Atmos. Meas. Tech., 12, 3673–3698, https://doi.org/10.5194/amt-12-3673-2019, https://doi.org/10.5194/amt-12-3673-2019, 2019
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This article presents the updated MAPIR algorithm, which uses infrared satellite data to obtain the global 3-D distribution of mineral aerosols. A description of the method together with its technical improvements is given. Additionally, a 10-year data set was generated and used to evaluate this new algorithm against AERONET, CALIOP, CATS and two ground-based lidar stations. We have shown that the new MAPIR algorithm provides reliable aerosol optical depth and dust layer mean altitude profiles.
Konstantina Nakoudi, Elina Giannakaki, Aggeliki Dandou, Maria Tombrou, and Mika Komppula
Atmos. Meas. Tech., 12, 2595–2610, https://doi.org/10.5194/amt-12-2595-2019, https://doi.org/10.5194/amt-12-2595-2019, 2019
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We characterized the height of the boundary layer (BLH) over New Delhi for almost a year using ground and satellite lidar measurements as well as model simulations. In the presence of multiple aerosol layers, the employed algorithm was very efficient. Due to prevailing meteorological conditions, the seasonal BLH cycle was slightly weaker than the one expected from the climatology. The aim was to assess the feasibility of the employed algorithm and compare the results to independent sources.
Ina Tegen, David Neubauer, Sylvaine Ferrachat, Colombe Siegenthaler-Le Drian, Isabelle Bey, Nick Schutgens, Philip Stier, Duncan Watson-Parris, Tanja Stanelle, Hauke Schmidt, Sebastian Rast, Harri Kokkola, Martin Schultz, Sabine Schroeder, Nikos Daskalakis, Stefan Barthel, Bernd Heinold, and Ulrike Lohmann
Geosci. Model Dev., 12, 1643–1677, https://doi.org/10.5194/gmd-12-1643-2019, https://doi.org/10.5194/gmd-12-1643-2019, 2019
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We describe a new version of the aerosol–climate model ECHAM–HAM and show tests of the model performance by comparing different aspects of the aerosol distribution with different datasets. The updated version of HAM contains improved descriptions of aerosol processes, including updated emission fields and cloud processes. While there are regional deviations between the model and observations, the model performs well overall.
Mona Kurppa, Antti Hellsten, Pontus Roldin, Harri Kokkola, Juha Tonttila, Mikko Auvinen, Christoph Kent, Prashant Kumar, Björn Maronga, and Leena Järvi
Geosci. Model Dev., 12, 1403–1422, https://doi.org/10.5194/gmd-12-1403-2019, https://doi.org/10.5194/gmd-12-1403-2019, 2019
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This paper describes the implementation of a sectional aerosol module, SALSA, into the PALM model system 6.0. The first evaluation study shows excellent agreements with measurements. Furthermore, we show that ignoring the dry deposition of aerosol particles can overestimate aerosol number concentrations by 20 %, whereas condensation and dissolutional growth increase the total aerosol mass by over 10 % in this specific urban environment.
Angela Buchholz, Andrew T. Lambe, Arttu Ylisirniö, Zijun Li, Olli-Pekka Tikkanen, Celia Faiola, Eetu Kari, Liqing Hao, Olli Luoma, Wei Huang, Claudia Mohr, Douglas R. Worsnop, Sergey A. Nizkorodov, Taina Yli-Juuti, Siegfried Schobesberger, and Annele Virtanen
Atmos. Chem. Phys., 19, 4061–4073, https://doi.org/10.5194/acp-19-4061-2019, https://doi.org/10.5194/acp-19-4061-2019, 2019
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We studied the evaporation of α-pinene secondary organic aerosol particles in clean air to derive their volatility from the observed size changes. We found that the particles became more resilient to evaporation with increased oxidative age, possibly increasing their lifetime in the atmosphere. Also, increased relative humidity increased the particle evaporation. Mass spectrometry measurements of the particles at different stages of evaporation revealed some water-induced composition changes.
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.
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.
Harri Kokkola, Thomas Kühn, Anton Laakso, Tommi Bergman, Kari E. J. Lehtinen, Tero Mielonen, Antti Arola, Scarlet Stadtler, Hannele Korhonen, Sylvaine Ferrachat, Ulrike Lohmann, David Neubauer, Ina Tegen, Colombe Siegenthaler-Le Drian, Martin G. Schultz, Isabelle Bey, Philip Stier, Nikos Daskalakis, Colette L. Heald, and Sami Romakkaniemi
Geosci. Model Dev., 11, 3833–3863, https://doi.org/10.5194/gmd-11-3833-2018, https://doi.org/10.5194/gmd-11-3833-2018, 2018
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In this paper we present a global aerosol–chemistry–climate model with the focus on its representation for atmospheric aerosol particles. In the model, aerosols are simulated using the aerosol module SALSA2.0, which in this paper is compared to satellite, ground, and aircraft-based observations of the properties of atmospheric aerosol. Based on this study, the model simulated aerosol properties compare well with the observations.
Kaisa Lakkala, Antti Arola, Julian Gröbner, Sergio Fabian León-Luis, Alberto Redondas, Stelios Kazadzis, Tomi Karppinen, Juha Matti Karhu, Luca Egli, Anu Heikkilä, Tapani Koskela, Antonio Serrano, and José Manuel Vilaplana
Atmos. Meas. Tech., 11, 5167–5180, https://doi.org/10.5194/amt-11-5167-2018, https://doi.org/10.5194/amt-11-5167-2018, 2018
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The performance of the cosine error correction method for correcting spectral UV measurements of the Brewer spectroradiometer was studied. The correction depends on the sky radiation distribution, which can change during one spectral scan. The results showed that the correction varied between 4 and 14 %, and that the relative differences between the reference and the Brewer diminished by 10 %. The method is applicable to other instruments as long as the required input parameters are available.
Maryam Dalirian, Arttu Ylisirniö, Angela Buchholz, Daniel Schlesinger, Johan Ström, Annele Virtanen, and Ilona Riipinen
Atmos. Chem. Phys., 18, 12477–12489, https://doi.org/10.5194/acp-18-12477-2018, https://doi.org/10.5194/acp-18-12477-2018, 2018
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Atmospheric black carbon (BC) particles are a concern due to their impact on air quality and climate. Their net climate effect is, however, still uncertain. In this study, laboratory measurements were performed to investigate cloud condensation nuclei (CCN) activity of BC particles, in pure state or coated by various organic species. Our results show that existing theories have potential in describing the CCN activation of atmospheric BC mixed with soluble pollutants.
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.
Scarlet Stadtler, Thomas Kühn, Sabine Schröder, Domenico Taraborrelli, Martin G. Schultz, and Harri Kokkola
Geosci. Model Dev., 11, 3235–3260, https://doi.org/10.5194/gmd-11-3235-2018, https://doi.org/10.5194/gmd-11-3235-2018, 2018
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Atmospheric aerosols interact with our climate system and have adverse health effects. Nevertheless, these particles are a source of uncertainty in climate projections and the formation process of secondary aerosols formed by organic gas-phase precursors is particularly not fully understood. In order to gain a deeper understanding of secondary organic aerosol formation, this model system explicitly represents gas-phase and aerosol formation processes. Finally, this allows for process discussion.
Robin G. Stevens, Katharina Loewe, Christopher Dearden, Antonios Dimitrelos, Anna Possner, Gesa K. Eirund, Tomi Raatikainen, Adrian A. Hill, Benjamin J. Shipway, Jonathan Wilkinson, Sami Romakkaniemi, Juha Tonttila, Ari Laaksonen, Hannele Korhonen, Paul Connolly, Ulrike Lohmann, Corinna Hoose, Annica M. L. Ekman, Ken S. Carslaw, and Paul R. Field
Atmos. Chem. Phys., 18, 11041–11071, https://doi.org/10.5194/acp-18-11041-2018, https://doi.org/10.5194/acp-18-11041-2018, 2018
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We perform a model intercomparison of summertime high Arctic clouds. Observed concentrations of aerosol particles necessary for cloud formation fell to extremely low values, coincident with a transition from cloudy to nearly cloud-free conditions. Previous analyses have suggested that at these low concentrations, the radiative properties of the clouds are determined primarily by these particle concentrations. The model results strongly support this hypothesis.
Lauri Laakso, Santtu Mikkonen, Achim Drebs, Anu Karjalainen, Pentti Pirinen, and Pekka Alenius
Ocean Sci., 14, 617–632, https://doi.org/10.5194/os-14-617-2018, https://doi.org/10.5194/os-14-617-2018, 2018
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Meteorological observations at Utö Atmospheric and Marine Research Station, the Baltic Sea, started in 1881 and seawater temperature and salinity observations in 1900. Based on the dataset of more than 100 years of observations, we see an increase in atmospheric temperature after the 1980s, in line with reduced sea ice cover. We also found an increase in seawater temperatures, modulated by changes in salinities. The results indicate that the climate at Utö may have shifted into a new phase.
Jorma Joutsensaari, Matthew Ozon, Tuomo Nieminen, Santtu Mikkonen, Timo Lähivaara, Stefano Decesari, M. Cristina Facchini, Ari Laaksonen, and Kari E. J. Lehtinen
Atmos. Chem. Phys., 18, 9597–9615, https://doi.org/10.5194/acp-18-9597-2018, https://doi.org/10.5194/acp-18-9597-2018, 2018
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New particle formation (NPF) in the atmosphere is globally an important source of aerosol particles. NPF events are typically identified and analyzed manually by researchers from particle size distribution data day by day, which is time consuming and might be inconsistent. We have developed an automatic analysis method based on deep learning for NPF event identification. The developed method can be easily utilized to analyze any long-term datasets more accurately and consistently.
Wiebke Frey, Dawei Hu, James Dorsey, M. Rami Alfarra, Aki Pajunoja, Annele Virtanen, Paul Connolly, and Gordon McFiggans
Atmos. Chem. Phys., 18, 9393–9409, https://doi.org/10.5194/acp-18-9393-2018, https://doi.org/10.5194/acp-18-9393-2018, 2018
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The coupled system of the Manchester Aerosol Chamber and Manchester Ice Cloud Chamber was used to study the ice-forming abilities of secondary
organic aerosol particles under mixed-phase cloud conditions. Given the vast abundance of secondary organic particles in the atmosphere, they
might present an important contribution to ice-nucleating particles. However, we find that in the studied temperature range (20 to 28 °C)
the secondary organic particles do not nucleate ice particles.
Ian Boutle, Jeremy Price, Innocent Kudzotsa, Harri Kokkola, and Sami Romakkaniemi
Atmos. Chem. Phys., 18, 7827–7840, https://doi.org/10.5194/acp-18-7827-2018, https://doi.org/10.5194/acp-18-7827-2018, 2018
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Aerosol processes are a key mechanism in the development of fog. Poor representation of aerosol–fog interaction can result in large biases in fog forecasts, such as surface temperatures which are too high and fog which is too deep and long lived. A relatively simple representation of aerosol–fog interaction can actually lead to significant improvements in forecasting. Aerosol–fog interaction can have a large effect on the climate system but is poorly represented in climate models.
Martin G. Schultz, Scarlet Stadtler, Sabine Schröder, Domenico Taraborrelli, Bruno Franco, Jonathan Krefting, Alexandra Henrot, Sylvaine Ferrachat, Ulrike Lohmann, David Neubauer, Colombe Siegenthaler-Le Drian, Sebastian Wahl, Harri Kokkola, Thomas Kühn, Sebastian Rast, Hauke Schmidt, Philip Stier, Doug Kinnison, Geoffrey S. Tyndall, John J. Orlando, and Catherine Wespes
Geosci. Model Dev., 11, 1695–1723, https://doi.org/10.5194/gmd-11-1695-2018, https://doi.org/10.5194/gmd-11-1695-2018, 2018
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The chemistry–climate model ECHAM-HAMMOZ contains a detailed representation of tropospheric and stratospheric reactive chemistry and state-of-the-art parameterizations of aerosols. It thus allows for detailed investigations of chemical processes in the climate system. Evaluation of the model with various observational data yields good results, but the model has a tendency to produce too much OH in the tropics. This highlights the important interplay between atmospheric chemistry and dynamics.
Pieternel F. Levelt, Joanna Joiner, Johanna Tamminen, J. Pepijn Veefkind, Pawan K. Bhartia, Deborah C. Stein Zweers, Bryan N. Duncan, David G. Streets, Henk Eskes, Ronald van der A, Chris McLinden, Vitali Fioletov, Simon Carn, Jos de Laat, Matthew DeLand, Sergey Marchenko, Richard McPeters, Jerald Ziemke, Dejian Fu, Xiong Liu, Kenneth Pickering, Arnoud Apituley, Gonzalo González Abad, Antti Arola, Folkert Boersma, Christopher Chan Miller, Kelly Chance, Martin de Graaf, Janne Hakkarainen, Seppo Hassinen, Iolanda Ialongo, Quintus Kleipool, Nickolay Krotkov, Can Li, Lok Lamsal, Paul Newman, Caroline Nowlan, Raid Suleiman, Lieuwe Gijsbert Tilstra, Omar Torres, Huiqun Wang, and Krzysztof Wargan
Atmos. Chem. Phys., 18, 5699–5745, https://doi.org/10.5194/acp-18-5699-2018, https://doi.org/10.5194/acp-18-5699-2018, 2018
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The aim of this paper is to highlight the many successes of the Ozone Monitoring Instrument (OMI) spanning more than 13 years. Data from OMI have been used in a wide range of applications. Due to its unprecedented spatial resolution, in combination with daily global coverage, OMI plays a unique role in measuring trace gases important for the ozone layer, air quality, and climate change. OMI data continue to be used for new research and applications.
Antti Lipponen, Tero Mielonen, Mikko R. A. Pitkänen, Robert C. Levy, Virginia R. Sawyer, Sami Romakkaniemi, Ville Kolehmainen, and Antti Arola
Atmos. Meas. Tech., 11, 1529–1547, https://doi.org/10.5194/amt-11-1529-2018, https://doi.org/10.5194/amt-11-1529-2018, 2018
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Atmospheric aerosols are small solid or liquid particles suspended in the atmosphere and they have a significant effect on the climate. Satellite data are used to get global estimates of atmospheric aerosols. In this work, a statistics-based Bayesian aerosol retrieval algorithm was developed to improve the accuracy and quantify the uncertainties related to the aerosol estimates. The algorithm is tested with NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) satellite data.
Wei Huang, Harald Saathoff, Aki Pajunoja, Xiaoli Shen, Karl-Heinz Naumann, Robert Wagner, Annele Virtanen, Thomas Leisner, and Claudia Mohr
Atmos. Chem. Phys., 18, 2883–2898, https://doi.org/10.5194/acp-18-2883-2018, https://doi.org/10.5194/acp-18-2883-2018, 2018
Anders V. Lindfors, Jukka Kujanpää, Niilo Kalakoski, Anu Heikkilä, Kaisa Lakkala, Tero Mielonen, Maarten Sneep, Nickolay A. Krotkov, Antti Arola, and Johanna Tamminen
Atmos. Meas. Tech., 11, 997–1008, https://doi.org/10.5194/amt-11-997-2018, https://doi.org/10.5194/amt-11-997-2018, 2018
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This paper describes the algorithm that will be used for estimating surface UV radiation from TROPOMI (TROPOspheric Monitoring Instrument) measurements. TROPOMI is the only payload of the Sentinel-5 Precursor (S5P), which is a polar-orbiting satellite mission of the European Space Agency (ESA). The presented algorithm has been tested using input based on previous satellite measurements. These preliminary results indicate that the algorithm is functioning according to expectations.
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.
Lukas Pichelstorfer, Dominik Stolzenburg, John Ortega, Thomas Karl, Harri Kokkola, Anton Laakso, Kari E. J. Lehtinen, James N. Smith, Peter H. McMurry, and Paul M. Winkler
Atmos. Chem. Phys., 18, 1307–1323, https://doi.org/10.5194/acp-18-1307-2018, https://doi.org/10.5194/acp-18-1307-2018, 2018
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Quantification of new particle formation as a source of atmospheric aerosol is clearly of importance for climate and health aspects. In our new study we developed two analysis methods that allow retrieval of nanoparticle growth dynamics at much higher precision than it was possible so far. Our results clearly demonstrate that growth rates show much more variation than is currently known and suggest that the Kelvin effect governs growth in the sub-10 nm size range.
William Wandji Nyamsi, Phillipe Blanc, John A. Augustine, Antti Arola, and Lucien Wald
Biogeosciences Discuss., https://doi.org/10.5194/bg-2017-512, https://doi.org/10.5194/bg-2017-512, 2018
Manuscript not accepted for further review
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This paper proposes a new, fast and accurate method for estimating photosynthetically active radiation at ground level in cloud-free conditions at any place and time. The method performs very well with the Copernicus Atmosphere Monitoring Service products as inputs describing the state of the atmosphere. An accuracy that is close to the uncertainty of the measurements themselves is reached. We believe that our research will be widely used in the near future.
William Wandji Nyamsi, Mikko R. A. Pitkänen, Youva Aoun, Philippe Blanc, Anu Heikkilä, Kaisa Lakkala, Germar Bernhard, Tapani Koskela, Anders V. Lindfors, Antti Arola, and Lucien Wald
Atmos. Meas. Tech., 10, 4965–4978, https://doi.org/10.5194/amt-10-4965-2017, https://doi.org/10.5194/amt-10-4965-2017, 2017
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This paper proposes a new, fast and accurate method for estimating UV fluxes at ground level in cloud-free conditions at any place and time. The method performs very well with the Copernicus Atmosphere Monitoring Service products as inputs describing the state of the atmosphere. An accuracy that is close to the uncertainty of the measurements themselves is reached. We believe that our research will be widely used in the near future.
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.
Maria Filioglou, Anna Nikandrova, Sami Niemelä, Holger Baars, Tero Mielonen, Ari Leskinen, David Brus, Sami Romakkaniemi, Elina Giannakaki, and Mika Komppula
Atmos. Meas. Tech., 10, 4303–4316, https://doi.org/10.5194/amt-10-4303-2017, https://doi.org/10.5194/amt-10-4303-2017, 2017
Peter W. Thorne, Fabio Madonna, Joerg Schulz, Tim Oakley, Bruce Ingleby, Marco Rosoldi, Emanuele Tramutola, Antti Arola, Matthias Buschmann, Anna C. Mikalsen, Richard Davy, Corinne Voces, Karin Kreher, Martine De Maziere, and Gelsomina Pappalardo
Geosci. Instrum. Method. Data Syst., 6, 453–472, https://doi.org/10.5194/gi-6-453-2017, https://doi.org/10.5194/gi-6-453-2017, 2017
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The term system-of-systems with respect to observational capabilities is frequently used, but what does it mean and how can it be assessed? Here, we define one possible interpretation of a system-of-systems architecture that is based upon demonstrable aspects of observing capabilities. We develop a set of assessment strands and then apply these to a set of atmospheric observational networks to decide which observations may be suitable for characterising satellite platforms in future work.
Sami Romakkaniemi, Zubair Maalick, Antti Hellsten, Antti Ruuskanen, Olli Väisänen, Irshad Ahmad, Juha Tonttila, Santtu Mikkonen, Mika Komppula, and Thomas Kühn
Atmos. Chem. Phys., 17, 7955–7964, https://doi.org/10.5194/acp-17-7955-2017, https://doi.org/10.5194/acp-17-7955-2017, 2017
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Surface topography affects aerosol–cloud interactions in boundary layer clouds. Local topography effects should be screened out from in situ observations before results can be generalised into a larger scale. Here we present modelling and observational results from a measurement station residing in a 75 m tower on top of a 150 m hill, and analyse how landscape affects the cloud formation, and which factors should be taken into account when aerosol effect on cloud droplet formation is studied.
Anton Laakso, Hannele Korhonen, Sami Romakkaniemi, and Harri Kokkola
Atmos. Chem. Phys., 17, 6957–6974, https://doi.org/10.5194/acp-17-6957-2017, https://doi.org/10.5194/acp-17-6957-2017, 2017
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Based on simulations, equatorial stratospheric sulfur injections have shown to be an efficient strategy to counteract ongoing global warming. However, equatorial injections would result in relatively larger cooling in low latitudes than in high latitudes. This together with greenhouse-gas-induced warming would lead to cooling in the Equator and warming in the high latitudes. Results of this study show that a more optimal cooling effect is achieved by varying the injection area seasonally.
Antti Arola, Thomas F. Eck, Harri Kokkola, Mikko R. A. Pitkänen, and Sami Romakkaniemi
Atmos. Chem. Phys., 17, 5991–6001, https://doi.org/10.5194/acp-17-5991-2017, https://doi.org/10.5194/acp-17-5991-2017, 2017
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One of the issues that hinder the measurement-based assessment of aerosol–cloud interactions by remote sensing methods is that typically aerosols and clouds cannot be measured simultaneously by passive remote sensing methods. AERONET includes the SDA product that provides the fine-mode AOD also in mixed cloud–aerosol observations. These measurements have not yet been fully exploited in studies of aerosol–cloud interactions. We applied SDA for this kind of analysis.
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.
Juha Tonttila, Zubair Maalick, Tomi Raatikainen, Harri Kokkola, Thomas Kühn, and Sami Romakkaniemi
Geosci. Model Dev., 10, 169–188, https://doi.org/10.5194/gmd-10-169-2017, https://doi.org/10.5194/gmd-10-169-2017, 2017
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Novel techniques for modelling the aerosol–cloud interactions are implemented in a cloud-resolving model. The new methods improve the representation of the poorly constrained effects of cloud processing, precipitation and the wet removal of particles on the aerosol population and the associated feedbacks. The detailed representation of these processes yields more realistic simulation of the evolution of boundary layer clouds and fogs, as compared to results obtained using more simple methods.
Tomi Raatikainen, David Brus, Rakesh K. Hooda, Antti-Pekka Hyvärinen, Eija Asmi, Ved P. Sharma, Antti Arola, and Heikki Lihavainen
Atmos. Chem. Phys., 17, 371–383, https://doi.org/10.5194/acp-17-371-2017, https://doi.org/10.5194/acp-17-371-2017, 2017
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We have measured black carbon aerosol properties in northern India at two sites: the first site is located at the polluted Indo-Gangetic Plain, while the second site is at the Himalayan foothills in a significantly cleaner environment. The observations show a clear difference in black carbon concentrations, but individual aerosol particles seem to be similar in both sites. Indirect evidence suggests that the particles are highly irregular resembling freshly emitted soot.
Stelios Kazadzis, Panagiotis Raptis, Natalia Kouremeti, Vassilis Amiridis, Antti Arola, Evangelos Gerasopoulos, and Gregory L. Schuster
Atmos. Meas. Tech., 9, 5997–6011, https://doi.org/10.5194/amt-9-5997-2016, https://doi.org/10.5194/amt-9-5997-2016, 2016
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Aerosols play an important role in the Earth's climate. One of the main aerosol properties is the single scattering albedo which is a measure of the aerosol absorption. In this work we have presented a method to retrieve this aerosol property in the ultraviolet and we presented the results for measurements at the urban environment of Athens, Greece. We show that the spectral dependence of the aerosol absorption in the VIS–IR and the UV range depends on the aerosol composition and type.
Colette Brogniez, Frédérique Auriol, Christine Deroo, Antti Arola, Jukka Kujanpää, Béatrice Sauvage, Niilo Kalakoski, Mikko Riku Aleksi Pitkänen, Maxime Catalfamo, Jean-Marc Metzger, Guy Tournois, and Pierre Da Conceicao
Atmos. Chem. Phys., 16, 15049–15074, https://doi.org/10.5194/acp-16-15049-2016, https://doi.org/10.5194/acp-16-15049-2016, 2016
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The atmospheric ozone layer is changing, thus the UV radiation at the surface is changing. Due to both beneficial and adverse effects of UV on the biosphere, monitoring of UV is essential. Satellite sensors provide estimates of UV at the surface with a global coverage. Validation of satellite-sensor UV is therefore needed and this can be done by comparison with ground-based measurements. The present validation in three sites (midlatitude, tropical) shows that OMI and GOME-2 provide reliable UV.
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.
Petri Tiitta, Ari Leskinen, Liqing Hao, Pasi Yli-Pirilä, Miika Kortelainen, Julija Grigonyte, Jarkko Tissari, Heikki Lamberg, Anni Hartikainen, Kari Kuuspalo, Aki-Matti Kortelainen, Annele Virtanen, Kari E. J. Lehtinen, Mika Komppula, Simone Pieber, André S. H. Prévôt, Timothy B. Onasch, Douglas R. Worsnop, Hendryk Czech, Ralf Zimmermann, Jorma Jokiniemi, and Olli Sippula
Atmos. Chem. Phys., 16, 13251–13269, https://doi.org/10.5194/acp-16-13251-2016, https://doi.org/10.5194/acp-16-13251-2016, 2016
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Real-time measurements of OA aging and SOA formation from logwood combustion were conducted under dark and UV oxidation. Substantial SOA formation was observed in all experiments, leading to twice the initial OA mass emphasizing the importance of the burning conditions for the aging processes. The results prove that emissions are subject to intensive chemical processing in the atmosphere; e.g. the most of the POA was found to become oxidized after the ozone addition, forming aged POA.
Aki Pajunoja, Weiwei Hu, Yu J. Leong, Nathan F. Taylor, Pasi Miettinen, Brett B. Palm, Santtu Mikkonen, Don R. Collins, Jose L. Jimenez, and Annele Virtanen
Atmos. Chem. Phys., 16, 11163–11176, https://doi.org/10.5194/acp-16-11163-2016, https://doi.org/10.5194/acp-16-11163-2016, 2016
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The phase state of ambient particles was inferred from bounce measurements conducted at a rural site in central Alabama during the SOAS campaign. The organic-dominated ambient particles are mostly in the liquid phase at summertime conditions but they turn semisolid when dried in the measurement setup. Bounce humidograms reveal that the hygroscopicity and oxidation of the particles decreases the liquefying RH. The effect of oxidation is emphasized by oxidation flow reactor measurements.
Elham Baranizadeh, Benjamin N. Murphy, Jan Julin, Saeed Falahat, Carly L. Reddington, Antti Arola, Lars Ahlm, Santtu Mikkonen, Christos Fountoukis, David Patoulias, Andreas Minikin, Thomas Hamburger, Ari Laaksonen, Spyros N. Pandis, Hanna Vehkamäki, Kari E. J. Lehtinen, and Ilona Riipinen
Geosci. Model Dev., 9, 2741–2754, https://doi.org/10.5194/gmd-9-2741-2016, https://doi.org/10.5194/gmd-9-2741-2016, 2016
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The molecular mechanisms through which new ultrafine (< 100 nm) aerosol particles are formed in the atmosphere have puzzled the scientific community for decades. In the past few years, however, significant progress has been made in unraveling these processes through laboratory studies and computational efforts. In this work we have implemented these new developments to an air quality model and study the implications of anthropogenically driven particle formation for European air quality.
Olli Väisänen, Antti Ruuskanen, Arttu Ylisirniö, Pasi Miettinen, Harri Portin, Liqing Hao, Ari Leskinen, Mika Komppula, Sami Romakkaniemi, Kari E. J. Lehtinen, and Annele Virtanen
Atmos. Chem. Phys., 16, 10385–10398, https://doi.org/10.5194/acp-16-10385-2016, https://doi.org/10.5194/acp-16-10385-2016, 2016
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In-cloud measurements of aerosol hygroscopicity and cloud droplet activation were conducted in Kuopio, Finland. According to the observations, the less hygroscopic accumulation mode particles were present in the non-activated aerosol, whereas the more hygroscopic particles were scavenged into cloud droplets. The results illustrate the sensitivity of cloud droplet formation to varying chemical composition and highlight the need for proper treatment of anthropogenic aerosols in CCN predictions.
Tero Mielonen, Anca Hienola, Thomas Kühn, Joonas Merikanto, Antti Lipponen, Tommi Bergman, Hannele Korhonen, Pekka Kolmonen, Larisa Sogacheva, Darren Ghent, Antti Arola, Gerrit de Leeuw, and Harri Kokkola
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2016-625, https://doi.org/10.5194/acp-2016-625, 2016
Revised manuscript not accepted
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We studied the temperature dependence of AOD and its radiative effects over the southeastern US. We used spaceborne observations of AOD, LST and tropospheric NO2 with simulations of ECHAM-HAMMOZ. The level of AOD in this region is governed by anthropogenic emissions but the temperature dependency is most likely caused by BVOC emissions. According to the observations and simulations, the regional clear-sky DRE for biogenic aerosols is −0.43 ± 0.88 W/m2/K and −0.86 ± 0.06 W/m2/K, respectively.
Jani Huttunen, Harri Kokkola, Tero Mielonen, Mika Esa Juhani Mononen, Antti Lipponen, Juha Reunanen, Anders Vilhelm Lindfors, Santtu Mikkonen, Kari Erkki Juhani Lehtinen, Natalia Kouremeti, Alkiviadis Bais, Harri Niska, and Antti Arola
Atmos. Chem. Phys., 16, 8181–8191, https://doi.org/10.5194/acp-16-8181-2016, https://doi.org/10.5194/acp-16-8181-2016, 2016
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For a good estimate of the current forcing by anthropogenic aerosols, knowledge in past is needed. One option to lengthen time series is to retrieve aerosol optical depth from solar radiation measurements. We have evaluated several methods for this task. Most of the methods produce aerosol optical depth estimates with a good accuracy. However, machine learning methods seem to be the most applicable not to produce any systematic biases, since they do not need constrain the aerosol properties.
Elina Giannakaki, Pieter G. van Zyl, Detlef Müller, Dimitris Balis, and Mika Komppula
Atmos. Chem. Phys., 16, 8109–8123, https://doi.org/10.5194/acp-16-8109-2016, https://doi.org/10.5194/acp-16-8109-2016, 2016
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Optical and microphysical properties of different aerosol types over South Africa measured with a multi-wavelength polarization Raman lidar are presented. Aerosol characterization of elevated layers was performed. This study could assist in bridging existing gaps relating to aerosol properties over South Africa.
Bernadette Rosati, Martin Gysel, Florian Rubach, Thomas F. Mentel, Brigitta Goger, Laurent Poulain, Patrick Schlag, Pasi Miettinen, Aki Pajunoja, Annele Virtanen, Henk Klein Baltink, J. S. Bas Henzing, Johannes Größ, Gian Paolo Gobbi, Alfred Wiedensohler, Astrid Kiendler-Scharr, Stefano Decesari, Maria Cristina Facchini, Ernest Weingartner, and Urs Baltensperger
Atmos. Chem. Phys., 16, 7295–7315, https://doi.org/10.5194/acp-16-7295-2016, https://doi.org/10.5194/acp-16-7295-2016, 2016
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This study presents PEGASOS project data from field campaigns in the Po Valley, Italy and the Netherlands. Vertical profiles of aerosol hygroscopicity and chemical composition were investigated with airborne measurements on board a Zeppelin NT airship. A special focus was on the evolution of different mixing layers within the PBL as a function of daytime. A closure study showed that variations in aerosol hygroscopicity can well be explained by the variations in chemical composition.
Jakke Sakari Mäkelä, Kaisa Lakkala, Tapani Koskela, Tomi Karppinen, Juha Matti Karhu, Vladimir Savastiouk, Hanne Suokanerva, Jussi Kaurola, Antti Arola, Anders Vilhelm Lindfors, Outi Meinander, Gerrit de Leeuw, and Anu Heikkilä
Geosci. Instrum. Method. Data Syst., 5, 193–203, https://doi.org/10.5194/gi-5-193-2016, https://doi.org/10.5194/gi-5-193-2016, 2016
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We describe the steps that are used at the Finnish Meteorological Institute (FMI) to process spectral ultraviolet (UV) radiation measurements made with its three Brewer spectrophotometers, located in Sodankylä (67° N) and Jokioinen (61° N). Multiple corrections are made to the data in near-real time and quality control is also performed automatically. Several data products are produced, including the near-real-time UV index and various daily dosages, and submitted to databases.
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
Ronny Engelmann, Thomas Kanitz, Holger Baars, Birgit Heese, Dietrich Althausen, Annett Skupin, Ulla Wandinger, Mika Komppula, Iwona S. Stachlewska, Vassilis Amiridis, Eleni Marinou, Ina Mattis, Holger Linné, and Albert Ansmann
Atmos. Meas. Tech., 9, 1767–1784, https://doi.org/10.5194/amt-9-1767-2016, https://doi.org/10.5194/amt-9-1767-2016, 2016
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The atmospheric science community demands for autonomous and quality-assured vertically resolved measurements of aerosol and cloud properties. For this purpose, a portable lidar called Polly
was developed at TROPOS in 2003. This lidar type was continuously improved with gained experience from EARLINET, worldwide field campaigns, and institute collaborations within the last 10 years. We present recent changes to the setup of our portable multiwavelength Raman and polarization lidar PollyXT.
Holger Baars, Thomas Kanitz, Ronny Engelmann, Dietrich Althausen, Birgit Heese, Mika Komppula, Jana Preißler, Matthias Tesche, Albert Ansmann, Ulla Wandinger, Jae-Hyun Lim, Joon Young Ahn, Iwona S. Stachlewska, Vassilis Amiridis, Eleni Marinou, Patric Seifert, Julian Hofer, Annett Skupin, Florian Schneider, Stephanie Bohlmann, Andreas Foth, Sebastian Bley, Anne Pfüller, Eleni Giannakaki, Heikki Lihavainen, Yrjö Viisanen, Rakesh Kumar Hooda, Sérgio Nepomuceno Pereira, Daniele Bortoli, Frank Wagner, Ina Mattis, Lucja Janicka, Krzysztof M. Markowicz, Peggy Achtert, Paulo Artaxo, Theotonio Pauliquevis, Rodrigo A. F. Souza, Ved Prakesh Sharma, Pieter Gideon van Zyl, Johan Paul Beukes, Junying Sun, Erich G. Rohwer, Ruru Deng, Rodanthi-Elisavet Mamouri, and Felix Zamorano
Atmos. Chem. Phys., 16, 5111–5137, https://doi.org/10.5194/acp-16-5111-2016, https://doi.org/10.5194/acp-16-5111-2016, 2016
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The findings from more than 10 years of global aerosol lidar measurements with Polly systems are summarized, and a data set of optical properties for specific aerosol types is given. An automated data retrieval algorithm for continuous Polly lidar observations is presented and discussed by means of a Saharan dust advection event in Leipzig, Germany. Finally, a statistic on the vertical aerosol distribution including the seasonal variability at PollyNET locations around the globe is presented.
Bernadette Rosati, Erik Herrmann, Silvia Bucci, Federico Fierli, Francesco Cairo, Martin Gysel, Ralf Tillmann, Johannes Größ, Gian Paolo Gobbi, Luca Di Liberto, Guido Di Donfrancesco, Alfred Wiedensohler, Ernest Weingartner, Annele Virtanen, Thomas F. Mentel, and Urs Baltensperger
Atmos. Chem. Phys., 16, 4539–4554, https://doi.org/10.5194/acp-16-4539-2016, https://doi.org/10.5194/acp-16-4539-2016, 2016
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We present vertical profiles of aerosol optical properties, which were explored within the planetary boundary layer in a case study in 2012 in the Po Valley region. A comparison of in situ measurements recorded aboard a Zeppelin NT and ground-based remote-sensing data was performed yielding good agreement. Additionally, the role of ambient relative humidity for the aerosol particles' optical properties was investigated.
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
N. I. Kristiansen, A. Stohl, D. J. L. Olivié, B. Croft, O. A. Søvde, H. Klein, T. Christoudias, D. Kunkel, S. J. Leadbetter, Y. H. Lee, K. Zhang, K. Tsigaridis, T. Bergman, N. Evangeliou, H. Wang, P.-L. Ma, R. C. Easter, P. J. Rasch, X. Liu, G. Pitari, G. Di Genova, S. Y. Zhao, Y. Balkanski, S. E. Bauer, G. S. Faluvegi, H. Kokkola, R. V. Martin, J. R. Pierce, M. Schulz, D. Shindell, H. Tost, and H. Zhang
Atmos. Chem. Phys., 16, 3525–3561, https://doi.org/10.5194/acp-16-3525-2016, https://doi.org/10.5194/acp-16-3525-2016, 2016
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Processes affecting aerosol removal from the atmosphere are not fully understood. In this study we investigate to what extent atmospheric transport models can reproduce observed loss of aerosols. We compare measurements of radioactive isotopes, that attached to ambient sulfate aerosols during the 2011 Fukushima nuclear accident, to 19 models using identical emissions. Results indicate aerosol removal that is too fast in most models, and apply to aerosols that have undergone long-range transport.
Zak Kipling, Philip Stier, Colin E. Johnson, Graham W. Mann, Nicolas Bellouin, Susanne E. Bauer, Tommi Bergman, Mian Chin, Thomas Diehl, Steven J. Ghan, Trond Iversen, Alf Kirkevåg, Harri Kokkola, Xiaohong Liu, Gan Luo, Twan van Noije, Kirsty J. Pringle, Knut von Salzen, Michael Schulz, Øyvind Seland, Ragnhild B. Skeie, Toshihiko Takemura, Kostas Tsigaridis, and Kai Zhang
Atmos. Chem. Phys., 16, 2221–2241, https://doi.org/10.5194/acp-16-2221-2016, https://doi.org/10.5194/acp-16-2221-2016, 2016
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The vertical distribution of atmospheric aerosol is an important factor in its effects on climate. In this study we use a sophisticated model of the many interacting processes affecting aerosol in the atmosphere to show that the vertical distribution is typically dominated by only a few of these processes. Constraining these physical processes may help to reduce the large differences between models. However, the important processes are not always the same for different types of aerosol.
G. L. Schuster, O. Dubovik, and A. Arola
Atmos. Chem. Phys., 16, 1565–1585, https://doi.org/10.5194/acp-16-1565-2016, https://doi.org/10.5194/acp-16-1565-2016, 2016
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We describe a method of using remote sensing of the refractive index to determine the relative contribution of carbonaceous aerosols and absorbing iron minerals. Monthly climatologies of fine mode soot carbon are low for West Africa and the Middle East, but the southern Africa and South America biomass burning sites have peak values that are much higher; this is consistent with expectations. Hence, refractive index is a practical parameter for quantifying soot carbon in the atmosphere.
G. L. Schuster, O. Dubovik, A. Arola, T. F. Eck, and B. N. Holben
Atmos. Chem. Phys., 16, 1587–1602, https://doi.org/10.5194/acp-16-1587-2016, https://doi.org/10.5194/acp-16-1587-2016, 2016
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Some authors have recently suggested that the spectral dependence of aerosol absorption may be used to separate soot carbon absorption from the aerosol absorption associated with organic carbon and dust. We demonstrate that this approach is inconsistent with the underlying assumptions that are required to infer aerosol absorption through remote sensing techniques, and that carbonaceous aerosols can not be differentiated from dust by exclusively using spectral absorption signatures.
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.
A. Laakso, H. Kokkola, A.-I. Partanen, U. Niemeier, C. Timmreck, K. E. J. Lehtinen, H. Hakkarainen, and H. Korhonen
Atmos. Chem. Phys., 16, 305–323, https://doi.org/10.5194/acp-16-305-2016, https://doi.org/10.5194/acp-16-305-2016, 2016
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We have studied the impacts of a volcanic eruption during solar radiation management (SRM) using an aerosol-climate model ECHAM5-HAM-SALSA and an Earth system model MPI-ESM. A volcanic eruption during stratospheric sulfur geoengineering would lead to larger particles and smaller amount of new particles than if an volcano erupts in normal atmospheric conditions. Thus, volcanic eruption during SRM would lead to only a small additional cooling which would last for a significantly shorter period.
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.
A. Arola, G. L. Schuster, M. R. A. Pitkänen, O. Dubovik, H. Kokkola, A. V. Lindfors, T. Mielonen, T. Raatikainen, S. Romakkaniemi, S. N. Tripathi, and H. Lihavainen
Atmos. Chem. Phys., 15, 12731–12740, https://doi.org/10.5194/acp-15-12731-2015, https://doi.org/10.5194/acp-15-12731-2015, 2015
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There have been relatively few measurement-based estimates for the direct radiative effect of brown carbon so far. This is first time that the direct radiative effect of brown carbon is estimated by exploiting the AERONET-retrieved imaginary indices. We estimated it for four sites in the Indo-Gangetic Plain: Karachi, Lahore,
Kanpur and Gandhi College.
H. Eskes, V. Huijnen, A. Arola, A. Benedictow, A.-M. Blechschmidt, E. Botek, O. Boucher, I. Bouarar, S. Chabrillat, E. Cuevas, R. Engelen, H. Flentje, A. Gaudel, J. Griesfeller, L. Jones, J. Kapsomenakis, E. Katragkou, S. Kinne, B. Langerock, M. Razinger, A. Richter, M. Schultz, M. Schulz, N. Sudarchikova, V. Thouret, M. Vrekoussis, A. Wagner, and C. Zerefos
Geosci. Model Dev., 8, 3523–3543, https://doi.org/10.5194/gmd-8-3523-2015, https://doi.org/10.5194/gmd-8-3523-2015, 2015
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The MACC project is preparing the operational atmosphere service of the European Copernicus Programme, and uses data assimilation to combine atmospheric models with available observations. Our paper provides an overview of the aerosol and trace gas validation activity of MACC. Topics are the validation requirements, the measurement data, the assimilation systems, the upgrade procedure, operational aspects and the scoring methods. A summary is provided of recent results, including special events.
J. Joutsensaari, P. Yli-Pirilä, H. Korhonen, A. Arola, J. D. Blande, J. Heijari, M. Kivimäenpää, S. Mikkonen, L. Hao, P. Miettinen, P. Lyytikäinen-Saarenmaa, C. L. Faiola, A. Laaksonen, and J. K. Holopainen
Atmos. Chem. Phys., 15, 12139–12157, https://doi.org/10.5194/acp-15-12139-2015, https://doi.org/10.5194/acp-15-12139-2015, 2015
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Global warming will induce large-scale insect outbreaks in boreal forests. Our results from field and laboratory experiments, satellite observations and global-scale modelling suggest that more frequent insect outbreaks, in addition to temperature-dependent increases in VOC emissions, could result in substantial increases in biogenic SOA formation and therefore affect both aerosol direct and indirect forcing of climate at regional scales. This should be considered in future climate predictions.
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
W. Wandji Nyamsi, A. Arola, P. Blanc, A. V. Lindfors, V. Cesnulyte, M. R. A. Pitkänen, and L. Wald
Atmos. Chem. Phys., 15, 7449–7456, https://doi.org/10.5194/acp-15-7449-2015, https://doi.org/10.5194/acp-15-7449-2015, 2015
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A novel model of the absorption of radiation by ozone in the UV bands [283, 307]nm and [307, 328]nm yields improvements in the modeling of the transmissivity in these bands. This model is faster than detailed spectral calculations and is as accurate with maximum errors of respectively 0.0006 and 0.0143. How to practically implement this new parameterization in a radiative transfer model is discussed for the case of libRadtran.
G. Bernhard, A. Arola, A. Dahlback, V. Fioletov, A. Heikkilä, B. Johnsen, T. Koskela, K. Lakkala, T. Svendby, and J. Tamminen
Atmos. Chem. Phys., 15, 7391–7412, https://doi.org/10.5194/acp-15-7391-2015, https://doi.org/10.5194/acp-15-7391-2015, 2015
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Surface erythemal UV data from the Ozone Monitoring Instrument (OMI) are validated for high northern latitudes (Arctic and Scandinavia) using ground-based measurements. The bias in OMI data caused by incorrect assumptions of the surface albedo are quantified and the mechanism that causes this bias is discussed. Methods to improve the accuracy of OMI data products are presented.
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.
M. A. Thomas, M. Kahnert, C. Andersson, H. Kokkola, U. Hansson, C. Jones, J. Langner, and A. Devasthale
Geosci. Model Dev., 8, 1885–1898, https://doi.org/10.5194/gmd-8-1885-2015, https://doi.org/10.5194/gmd-8-1885-2015, 2015
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We have showed that a coupled modelling system is beneficial in the sense that more complex processes can be included to better represent the aerosol processes starting from their formation, their interactions with clouds and provide better estimate of radiative forcing. Using this model set up, we estimated an annual mean 'indirect' radiative forcing of -0.64W/m2. This means that aerosols, solely by their capability of altering the microphysical properties of clouds can cool the Earth system.
A. Leskinen, P. Yli-Pirilä, K. Kuuspalo, O. Sippula, P. Jalava, M.-R. Hirvonen, J. Jokiniemi, A. Virtanen, M. Komppula, and K. E. J. Lehtinen
Atmos. Meas. Tech., 8, 2267–2278, https://doi.org/10.5194/amt-8-2267-2015, https://doi.org/10.5194/amt-8-2267-2015, 2015
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A 29 m3 Teflon chamber was characterized and tested with oxidation experiments of toluene. Secondary organic aerosol yields of 12-42 % were obtained. These yields are comparable to those obtained in other laboratories.
E. Giannakaki, A. Pfüller, K. Korhonen, T. Mielonen, L. Laakso, V. Vakkari, H. Baars, R. Engelmann, J. P. Beukes, P. G. Van Zyl, M. Josipovic, P. Tiitta, K. Chiloane, S. Piketh, H. Lihavainen, K. E. J. Lehtinen, and M. Komppula
Atmos. Chem. Phys., 15, 5429–5442, https://doi.org/10.5194/acp-15-5429-2015, https://doi.org/10.5194/acp-15-5429-2015, 2015
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In this study we summarize 1 year of Raman lidar observations over South Africa. The analyses of lidar measurements presented here could assist in bridging existing gaps in the knowledge of vertical distribution of aerosols above South Africa, since limited long-term data of this type are available for this region. For the first time, we have been able to cover the full seasonal cycle on geometrical characteristics and optical properties of free tropospheric aerosol layers in the region.
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
M. Dalirian, H. Keskinen, L. Ahlm, A. Ylisirniö, S. Romakkaniemi, A. Laaksonen, A. Virtanen, and I. Riipinen
Atmos. Chem. Phys., 15, 3815–3829, https://doi.org/10.5194/acp-15-3815-2015, https://doi.org/10.5194/acp-15-3815-2015, 2015
C. Andersson, R. Bergström, C. Bennet, L. Robertson, M. Thomas, H. Korhonen, K. E. J. Lehtinen, and H. Kokkola
Geosci. Model Dev., 8, 171–189, https://doi.org/10.5194/gmd-8-171-2015, https://doi.org/10.5194/gmd-8-171-2015, 2015
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We have integrated the sectional aerosol dynamics model SALSA into the European scale chemistry-transport model MATCH. The combined model reproduces observed higher particle number concentration (PNCs) in central Europe and lower concentrations in remote regions; however, the total PNC is underestimated. The low nucleation rate coefficient used in this study is an important reason for the underestimation.
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.
M. R. A. Pitkänen, A. Arola, K. Lakkala, T. Koskela, and A. V. Lindfors
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amtd-8-487-2015, https://doi.org/10.5194/amtd-8-487-2015, 2015
Revised manuscript not accepted
E. M. Dunne, S. Mikkonen, H. Kokkola, and H. Korhonen
Atmos. Chem. Phys., 14, 13631–13642, https://doi.org/10.5194/acp-14-13631-2014, https://doi.org/10.5194/acp-14-13631-2014, 2014
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Marine clouds have a strong effect on the Earth's radiative balance. One proposed climate feedback is that, in a warming climate, marine aerosol emissions will change due to changing wind speeds. We have examined the processes that affect aerosol emissions and removal over 15 years, and high-temporal-resolution output over 2 months. We conclude that wind trends are unlikely to cause a strong feedback in marine regions, but changes in removal processes or transport from continental regions may.
L. Q. Hao, A. Kortelainen, S. Romakkaniemi, H. Portin, A. Jaatinen, A. Leskinen, M. Komppula, P. Miettinen, D. Sueper, A. Pajunoja, J. N. Smith, K. E. J. Lehtinen, D. R. Worsnop, A. Laaksonen, and A. Virtanen
Atmos. Chem. Phys., 14, 13483–13495, https://doi.org/10.5194/acp-14-13483-2014, https://doi.org/10.5194/acp-14-13483-2014, 2014
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Positive matrix factorization (PMF) was applied to the unified high-resolution mass spectra organic species with NO+ and NO2+ ions from the measurement in a mixed region between the boreal forestland and the urban area. The PMF analysis succeeded in separating the mixed spectra into three distinct organic factors and one inorganic factor. The particulate organic nitrate was distinguished by PMF for the first time, with a contribution of one-third of the total nitrate mass.
A.-I. Partanen, E. M. Dunne, T. Bergman, A. Laakso, H. Kokkola, J. Ovadnevaite, L. Sogacheva, D. Baisnée, J. Sciare, A. Manders, C. O'Dowd, G. de Leeuw, and H. Korhonen
Atmos. Chem. Phys., 14, 11731–11752, https://doi.org/10.5194/acp-14-11731-2014, https://doi.org/10.5194/acp-14-11731-2014, 2014
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New parameterizations for the sea spray aerosol source flux and its organic fraction were incorporated into a global aerosol-climate model. The emissions of sea salt were considerably less than previous estimates. This study demonstrates that sea spray aerosol may actually decrease the number of cloud droplets, which has a warming effect on climate. Overall, sea spray aerosol was predicted to have a global cooling effect due to the scattering of solar radiation from sea spray aerosol particles.
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
T. F. Eck, B. N. Holben, J. S. Reid, A. Arola, R. A. Ferrare, C. A. Hostetler, S. N. Crumeyrolle, T. A. Berkoff, E. J. Welton, S. Lolli, A. Lyapustin, Y. Wang, J. S. Schafer, D. M. Giles, B. E. Anderson, K. L. Thornhill, P. Minnis, K. E. Pickering, C. P. Loughner, A. Smirnov, and A. Sinyuk
Atmos. Chem. Phys., 14, 11633–11656, https://doi.org/10.5194/acp-14-11633-2014, https://doi.org/10.5194/acp-14-11633-2014, 2014
K. Tsigaridis, N. Daskalakis, M. Kanakidou, P. J. Adams, P. Artaxo, R. Bahadur, Y. Balkanski, S. E. Bauer, N. Bellouin, A. Benedetti, T. Bergman, T. K. Berntsen, J. P. Beukes, H. Bian, K. S. Carslaw, M. Chin, G. Curci, T. Diehl, R. C. Easter, S. J. Ghan, S. L. Gong, A. Hodzic, C. R. Hoyle, T. Iversen, S. Jathar, J. L. Jimenez, J. W. Kaiser, A. Kirkevåg, D. Koch, H. Kokkola, Y. H Lee, G. Lin, X. Liu, G. Luo, X. Ma, G. W. Mann, N. Mihalopoulos, J.-J. Morcrette, J.-F. Müller, G. Myhre, S. Myriokefalitakis, N. L. Ng, D. O'Donnell, J. E. Penner, L. Pozzoli, K. J. Pringle, L. M. Russell, M. Schulz, J. Sciare, Ø. Seland, D. T. Shindell, S. Sillman, R. B. Skeie, D. Spracklen, T. Stavrakou, S. D. Steenrod, T. Takemura, P. Tiitta, S. Tilmes, H. Tost, T. van Noije, P. G. van Zyl, K. von Salzen, F. Yu, Z. Wang, Z. Wang, R. A. Zaveri, H. Zhang, K. Zhang, Q. Zhang, and X. Zhang
Atmos. Chem. Phys., 14, 10845–10895, https://doi.org/10.5194/acp-14-10845-2014, https://doi.org/10.5194/acp-14-10845-2014, 2014
J. Huttunen, A. Arola, G. Myhre, A. V. Lindfors, T. Mielonen, S. Mikkonen, J. S. Schafer, S. N. Tripathi, M. Wild, M. Komppula, and K. E. J. Lehtinen
Atmos. Chem. Phys., 14, 6103–6110, https://doi.org/10.5194/acp-14-6103-2014, https://doi.org/10.5194/acp-14-6103-2014, 2014
H. Portin, A. Leskinen, L. Hao, A. Kortelainen, P. Miettinen, A. Jaatinen, A. Laaksonen, K. E. J. Lehtinen, S. Romakkaniemi, and M. Komppula
Atmos. Chem. Phys., 14, 6021–6034, https://doi.org/10.5194/acp-14-6021-2014, https://doi.org/10.5194/acp-14-6021-2014, 2014
O. Meinander, A. Kontu, A. Virkkula, A. Arola, L. Backman, P. Dagsson-Waldhauserová, O. Järvinen, T. Manninen, J. Svensson, G. de Leeuw, and M. Leppäranta
The Cryosphere, 8, 991–995, https://doi.org/10.5194/tc-8-991-2014, https://doi.org/10.5194/tc-8-991-2014, 2014
S. Romakkaniemi, A. Jaatinen, A. Laaksonen, A. Nenes, and T. Raatikainen
Atmos. Meas. Tech., 7, 1377–1384, https://doi.org/10.5194/amt-7-1377-2014, https://doi.org/10.5194/amt-7-1377-2014, 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
K. Korhonen, E. Giannakaki, T. Mielonen, A. Pfüller, L. Laakso, V. Vakkari, H. Baars, R. Engelmann, J. P. Beukes, P. G. Van Zyl, A. Ramandh, L. Ntsangwane, M. Josipovic, P. Tiitta, G. Fourie, I. Ngwana, K. Chiloane, and M. Komppula
Atmos. Chem. Phys., 14, 4263–4278, https://doi.org/10.5194/acp-14-4263-2014, https://doi.org/10.5194/acp-14-4263-2014, 2014
H. Kokkola, P. Yli-Pirilä, M. Vesterinen, H. Korhonen, H. Keskinen, S. Romakkaniemi, L. Hao, A. Kortelainen, J. Joutsensaari, D. R. Worsnop, A. Virtanen, and K. E. J. Lehtinen
Atmos. Chem. Phys., 14, 1689–1700, https://doi.org/10.5194/acp-14-1689-2014, https://doi.org/10.5194/acp-14-1689-2014, 2014
T. Korhola, H. Kokkola, H. Korhonen, A.-I. Partanen, A. Laaksonen, K. E. J. Lehtinen, and S. Romakkaniemi
Geosci. Model Dev., 7, 161–174, https://doi.org/10.5194/gmd-7-161-2014, https://doi.org/10.5194/gmd-7-161-2014, 2014
V. Cesnulyte, A. V. Lindfors, M. R. A. Pitkänen, K. E. J. Lehtinen, J.-J. Morcrette, and A. Arola
Atmos. Chem. Phys., 14, 593–608, https://doi.org/10.5194/acp-14-593-2014, https://doi.org/10.5194/acp-14-593-2014, 2014
A. Lipponen, V. Kolehmainen, S. Romakkaniemi, and H. Kokkola
Geosci. Model Dev., 6, 2087–2098, https://doi.org/10.5194/gmd-6-2087-2013, https://doi.org/10.5194/gmd-6-2087-2013, 2013
A. I. Partanen, A. Laakso, A. Schmidt, H. Kokkola, T. Kuokkanen, J.-P. Pietikäinen, V.-M. Kerminen, K. E. J. Lehtinen, L. Laakso, and H. Korhonen
Atmos. Chem. Phys., 13, 12059–12071, https://doi.org/10.5194/acp-13-12059-2013, https://doi.org/10.5194/acp-13-12059-2013, 2013
M. Lefèvre, A. Oumbe, P. Blanc, B. Espinar, B. Gschwind, Z. Qu, L. Wald, M. Schroedter-Homscheidt, C. Hoyer-Klick, A. Arola, A. Benedetti, J. W. Kaiser, and J.-J. Morcrette
Atmos. Meas. Tech., 6, 2403–2418, https://doi.org/10.5194/amt-6-2403-2013, https://doi.org/10.5194/amt-6-2403-2013, 2013
A. Arola, T. F. Eck, J. Huttunen, K. E. J. Lehtinen, A. V. Lindfors, G. Myhre, A. Smirnov, S. N. Tripathi, and H. Yu
Atmos. Chem. Phys., 13, 7895–7901, https://doi.org/10.5194/acp-13-7895-2013, https://doi.org/10.5194/acp-13-7895-2013, 2013
A. V. Lindfors, N. Kouremeti, A. Arola, S. Kazadzis, A. F. Bais, and A. Laaksonen
Atmos. Chem. Phys., 13, 3733–3741, https://doi.org/10.5194/acp-13-3733-2013, https://doi.org/10.5194/acp-13-3733-2013, 2013
Related subject area
Subject: Aerosols | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
Elucidating ozone and PM2.5 pollution in the Fenwei Plain reveals the co-benefits of controlling precursor gas emissions in winter haze
Quantifying particle-to-particle heterogeneity in aerosol hygroscopicity
Measurement report: Black carbon properties and concentrations in southern Sweden urban and rural air – the importance of long-range transport
Diurnal differences in the effect of aerosols on cloud-to-ground lightning in the Sichuan Basin
Intensive aerosol properties of boreal and regional biomass burning aerosol at Mt. Bachelor Observatory: larger and black carbon (BC)-dominant particles transported from Siberian wildfires
Characterization of ultrafine particles and the occurrence of new particle formation events in an urban and coastal site of the Mediterranean area
Atmospheric nanoparticles hygroscopic growth measurement by a combined surface plasmon resonance microscope and hygroscopic tandem differential mobility analyzer
A full year of aerosol size distribution data from the central Arctic under an extreme positive Arctic Oscillation: insights from the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition
Annual cycle of hygroscopic properties and mixing state of the suburban aerosol in Athens, Greece
Measurement report: Atmospheric new particle formation at a peri-urban site in Lille, northern France
New particle formation and growth during summer in an urban environment: a dual chamber study
An evaluation of biomass burning aerosol mass, extinction, and size distribution in GEOS using observations from CAMP2Ex
Seasonal significance of new particle formation impacts on cloud condensation nuclei at a mountaintop location
Aerosol activation characteristics and prediction at the central European ACTRIS research station of Melpitz, Germany
Measurement report: Increasing trend of atmospheric ion concentrations in the boreal forest
Vertical profiles of cloud condensation nuclei number concentration and its empirical estimate from aerosol optical properties over the North China Plain
Measurement report: The Urmia playa as a source of airborne dust and ice-nucleating particles – Part 1: Correlation between soils and airborne samples
Constraining the particle-scale diversity of black carbon light absorption using a unified framework
Ice Nucleating Particles in Northern Greenland: annual cycles, biological contribution and parameterizations
Survival probability of new atmospheric particles: closure between theory and measurements from 1.4 to 100 nm
Predicting atmospheric background number concentration of ice-nucleating particles in the Arctic
Different effects of anthropogenic emissions and aging processes on the mixing state of soot particles in the nucleation and accumulation modes
Fluorescence characteristics, absorption properties, and radiative effects of water-soluble organic carbon in seasonal snow across northeastern China
Measurement report: Size distributions of urban aerosols down to 1 nm from long-term measurements
Rapid reappearance of air pollution after cold air outbreaks in northern and eastern China
On the relation between apparent ion and total particle growth rates in the boreal forest and related chamber experiments
Aerosol deposition to the boreal forest in the vicinity of the Alberta Oil Sands
Assessment of NAAPS-RA performance in Maritime Southeast Asia during CAMP2Ex
Comparison of particle number size distribution trends in ground measurements and climate models
Aerosol size distribution changes in FIREX-AQ biomass burning plumes: the impact of plume concentration on coagulation and OA condensation/evaporation
Long-range transported continental aerosol in the Eastern North Atlantic: three multiday event regimes influence cloud condensation nuclei
Impact of water uptake and mixing state on submicron particle deposition in the human respiratory tract (HRT) based on explicit hygroscopicity measurements at HRT-like conditions
Parameterizations of size distribution and refractive index of biomass burning organic aerosol with black carbon content
Newly identified climatically and environmentally significant high-latitude dust sources
Measurement Report: Understanding the seasonal cycle of Southern Ocean aerosols
Airborne observations during KORUS-AQ show that aerosol optical depths are more spatially self-consistent than aerosol intensive properties
Using aircraft measurements to characterize subgrid-scale variability of aerosol properties near the Atmospheric Radiation Measurement Southern Great Plains site
Variations of the density of ambient black carbon retrieved by a new method: importance to CCN prediction
Measurement report: A multi-year study on the impacts of Chinese New Year celebrations on air quality in Beijing, China
Mixing state of black carbon at different atmospheres in north and southwest China
Columnar and surface urban aerosol in the Moscow megacity according to measurements and simulations with the COSMO-ART model
Vertical aerosol particle exchange in the marine boundary layer estimated from helicopter-borne measurements in the Azores region
Circum-Antarctic abundance and properties of CCN and INPs
The ice-nucleating activity of African mineral dust in the Caribbean boundary layer
Biomass burning and marine aerosol processing over the southeast Atlantic Ocean: a TEM single-particle analysis
Volatility parameterization of ambient organic aerosols at a rural site of the North China Plain
Light absorption by brown carbon over the South-East Atlantic Ocean
Particle size distribution and particulate matter concentrations during synoptic and convective dust events in West Texas
Measurement of light-absorbing particles in surface snow of central and western Himalayan glaciers: spatial variability, radiative impacts, and potential source regions
Seasonal variations in fire conditions are important drivers in the trend of aerosol optical properties over the south-eastern Atlantic
Chunshui Lin, Ru-Jin Huang, Haobin Zhong, Jing Duan, Zixi Wang, Wei Huang, and Wei Xu
Atmos. Chem. Phys., 23, 3595–3607, https://doi.org/10.5194/acp-23-3595-2023, https://doi.org/10.5194/acp-23-3595-2023, 2023
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The complex interaction between O3 and PM2.5, coupled with the topology of the Fenwei Plain and the evolution of the boundary layer height, highlights the challenges in further reducing particulate pollution in winter despite years of efforts to reduce emissions. Through scenario analysis in a chemical box model constrained by observation, we show the co-benefits of reducing NOx and VOCs simultaneously in reducing ozone and SOA.
Liang Yuan and Chunsheng Zhao
Atmos. Chem. Phys., 23, 3195–3205, https://doi.org/10.5194/acp-23-3195-2023, https://doi.org/10.5194/acp-23-3195-2023, 2023
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Chemical compositions vary between and within particles due to the complex sources and aging processes, causing particle-to-particle heterogeneity in aerosol hygroscopicity, which is of great importance to aerosol climatic and environmental effects. This study proposes an algorithm to quantify the heterogeneity from in situ measurements, sheds light on the reanalysis of the existing H-TDMA datasets, and could have a large impact on how we use and think about these datasets.
Erik Ahlberg, Stina Ausmeel, Lovisa Nilsson, Mårten Spanne, Julija Pauraite, Jacob Klenø Nøjgaard, Michele Bertò, Henrik Skov, Pontus Roldin, Adam Kristensson, Erik Swietlicki, and Axel Eriksson
Atmos. Chem. Phys., 23, 3051–3064, https://doi.org/10.5194/acp-23-3051-2023, https://doi.org/10.5194/acp-23-3051-2023, 2023
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To investigate the properties and origin of black carbon particles in southern Sweden during late summer, we performed measurements both at a rural site and the nearby city of Malmö. We found that local traffic emissions of black carbon led to concentrations around twice as high as those at the rural site. Modeling show that these emissions are not clearly distinguishable at the rural site, unless meteorology was favourable, which shows the importance of long-range transport and processing.
Haichao Wang, Yongbo Tan, Zheng Shi, Ning Yang, and Tianxue Zheng
Atmos. Chem. Phys., 23, 2843–2857, https://doi.org/10.5194/acp-23-2843-2023, https://doi.org/10.5194/acp-23-2843-2023, 2023
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The effects of aerosols on lightning are complex and still far from understood. We analysed the impacts of aerosols on lightning activity in the Sichuan Basin. Results show that lightning flashes first increase with aerosol loading during all periods and then behave differently (decrease in the afternoon and flatten at night). This suggests that the changes in solar radiation can modulate the aerosol effects on the occurrence and development of convection and lightning activity.
Nathaniel W. May, Noah Bernays, Ryan Farley, Qi Zhang, and Daniel A. Jaffe
Atmos. Chem. Phys., 23, 2747–2764, https://doi.org/10.5194/acp-23-2747-2023, https://doi.org/10.5194/acp-23-2747-2023, 2023
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In summer 2019 at Mt. Bachelor Observatory, we observed smoke from wildfires with transport times ranging from less than a day up to 2 weeks. Aerosol absorption of multi-day transported smoke was dominated by black carbon, while smoke with shorter transport times had greater brown carbon absorption. Notably, Siberian smoke exhibited aerosol scattering and physical properties indicative of contributions from larger particles than typically observed in smoke.
Adelaide Dinoi, Daniel Gulli, Kay Weinhold, Ivano Ammoscato, Claudia R. Calidonna, Alfred Wiedensohler, and Daniele Contini
Atmos. Chem. Phys., 23, 2167–2181, https://doi.org/10.5194/acp-23-2167-2023, https://doi.org/10.5194/acp-23-2167-2023, 2023
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In this study, particle number size distribution analysis was performed with the purpose of characterizing new particle formation (NPF) events occurring in two areas of southern Italy over 5 years of measurements. The identification of NPF events produced different results in terms of frequency and seasonality. Some of the main variables involved in the process, the local atmospheric conditions in which the events occurred, and the role of the air masses were discussed and compared.
Zhibo Xie, Jiaoshi Zhang, Huaqiao Gui, Yang Liu, Bo Yang, Haosheng Dai, Hang Xiao, Douguo Zhang, Da-Ren Chen, and Jianguo Liu
Atmos. Chem. Phys., 23, 2079–2088, https://doi.org/10.5194/acp-23-2079-2023, https://doi.org/10.5194/acp-23-2079-2023, 2023
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The hygroscopic growth of single nanoparticles is important for hygroscopic characteristic analysis of atmospheric particles and for scientific studies involving atmospheric particles. Based on the hygroscopicity difference of subgroups of atmospheric nanoparticles, the classification and proportion analysis of atmospheric nanoparticles has been completed, which has potential significance in predicting the contribution of the atmospheric particulate hygroscopicity and particle growth mechanism.
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.
Christina Spitieri, Maria Gini, Martin Gysel-Beer, and Konstantinos Eleftheriadis
Atmos. Chem. Phys., 23, 235–249, https://doi.org/10.5194/acp-23-235-2023, https://doi.org/10.5194/acp-23-235-2023, 2023
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The paper provides insights into the hygroscopic properties and state of mixing of atmospheric aerosol through 1 year of measurements of key microphysical parameters in the suburbs of the most densely populated city of Greece, Athens, in the eastern Mediterranean, which is considered an important climate change hotspot. The results can be used for the prediction of cloud condensation nuclei and quantification of the influence of ambient relative humidity on light scattering by aerosol particles.
Suzanne Crumeyrolle, Jenni S. S. Kontkanen, Clémence Rose, Alejandra Velazquez Garcia, Eric Bourrianne, Maxime Catalfamo, Véronique Riffault, Emmanuel Tison, Joel Ferreira de Brito, Nicolas Visez, Nicolas Ferlay, Frédérique Auriol, and Isabelle Chiapello
Atmos. Chem. Phys., 23, 183–201, https://doi.org/10.5194/acp-23-183-2023, https://doi.org/10.5194/acp-23-183-2023, 2023
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Ultrafine particles (UFPs) are particles with an aerodynamic diameter of 100 nm or less and negligible mass concentration but are the dominant contributor to the total particle number concentration. The present study aims to better understand the environmental factors favoring or inhibiting atmospheric new particle formation (NPF) over Lille, a large city in the north of France, and to analyze the impact of such an event on urban air quality using a long-term dataset (3 years).
Spiro D. Jorga, Kalliopi Florou, David Patoulias, and Spyros N. Pandis
Atmos. Chem. Phys., 23, 85–97, https://doi.org/10.5194/acp-23-85-2023, https://doi.org/10.5194/acp-23-85-2023, 2023
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We take advantage of this unexpected low, new particle formation frequency in Greece and use a dual atmospheric simulation chamber system with starting point ambient air in an effort to gain insight about the chemical species that is limiting nucleation in this area. A potential nucleation precursor, ammonia, was added in one of the chambers while the other one was used as a reference. The addition of ammonia assisted new particle formation in almost 50 % of the experiments conducted.
Allison B. Marquardt Collow, Virginie Buchard, Peter R. Colarco, Arlindo M. da Silva, Ravi Govindaraju, Edward P. Nowottnick, Sharon Burton, Richard Ferrare, Chris Hostetler, and Luke Ziemba
Atmos. Chem. Phys., 22, 16091–16109, https://doi.org/10.5194/acp-22-16091-2022, https://doi.org/10.5194/acp-22-16091-2022, 2022
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Biomass burning aerosol impacts aspects of the atmosphere and Earth system through radiative forcing, serving as cloud condensation nuclei, and air quality. Despite its importance, the representation of biomass burning aerosol is not always accurate in models. Field campaign observations from CAMP2Ex are used to evaluate the mass and extinction of aerosols in the GEOS model. Notable biases in the model illuminate areas of future development with GEOS and the underlying GOCART aerosol module.
Noah S. Hirshorn, Lauren M. Zuromski, Christopher Rapp, Ian McCubbin, Gerardo Carrillo-Cardenas, Fangqun Yu, and A. Gannet Hallar
Atmos. Chem. Phys., 22, 15909–15924, https://doi.org/10.5194/acp-22-15909-2022, https://doi.org/10.5194/acp-22-15909-2022, 2022
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New particle formation (NPF) is a source of atmospheric aerosol number concentration that can impact climate by growing to larger sizes and under proper conditions form cloud condensation nuclei (CCN). Using novel methods, we find that at Storm Peak Laboratory, a remote, mountaintop site in Colorado, NPF is observed to enhance CCN concentrations in the spring by a factor of 1.54 and in the winter by a factor of 1.36 which can occur on a regional scale having important climate implications.
Yuan Wang, Silvia Henning, Laurent Poulain, Chunsong Lu, Frank Stratmann, Yuying Wang, Shengjie Niu, Mira L. Pöhlker, Hartmut Herrmann, and Alfred Wiedensohler
Atmos. Chem. Phys., 22, 15943–15962, https://doi.org/10.5194/acp-22-15943-2022, https://doi.org/10.5194/acp-22-15943-2022, 2022
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Aerosol particle activation affects cloud, precipitation, radiation, and thus the global climate. Its long-term measurements are important but still scarce. In this study, more than 4 years of measurements at a central European station were analyzed. The overall characteristics and seasonal changes of aerosol particle activation are summarized. The power-law fit between particle hygroscopicity factor and diameter was recommended for predicting cloud
condensation nuclei number concentration.
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.
Rui Zhang, Yuying Wang, Zhanqing Li, Zhibin Wang, Russell R. Dickerson, Xinrong Ren, Hao He, Fei Wang, Ying Gao, Xi Chen, Jialu Xu, Yafang Cheng, and Hang Su
Atmos. Chem. Phys., 22, 14879–14891, https://doi.org/10.5194/acp-22-14879-2022, https://doi.org/10.5194/acp-22-14879-2022, 2022
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Factors of cloud condensation nuclei number concentration (NCCN) profiles determined in the North China Plain include air mass sources, temperature structure, anthropogenic emissions, and terrain distribution. Cloud condensation nuclei (CCN) spectra suggest that the ability of aerosol activation into CCN is stronger in southeasterly than in northwesterly air masses and stronger in the free atmosphere than near the surface. A good method to parameterize NCCN from aerosol optical data is found.
Nikou Hamzehpour, Claudia Marcolli, Sara Pashai, Kristian Klumpp, and Thomas Peter
Atmos. Chem. Phys., 22, 14905–14930, https://doi.org/10.5194/acp-22-14905-2022, https://doi.org/10.5194/acp-22-14905-2022, 2022
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Playa surfaces in Iran that emerged through Lake Urmia (LU) desiccation have become a relevant dust source of regional relevance. Here, we identify highly erodible LU playa surfaces and determine their physicochemical properties and mineralogical composition and perform emulsion-freezing experiments with them. We find high ice nucleation activities (up to 250 K) that correlate positively with organic matter and clay content and negatively with pH, salinity, K-feldspars, and quartz.
Payton Beeler and Rajan K. Chakrabarty
Atmos. Chem. Phys., 22, 14825–14836, https://doi.org/10.5194/acp-22-14825-2022, https://doi.org/10.5194/acp-22-14825-2022, 2022
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Understanding and parameterizing the influences of black carbon (BC) particle morphology and compositional heterogeneity on its light absorption represent a fundamental problem. We develop scaling laws using a single unifying parameter that effectively encompasses large-scale diversity observed in BC light absorption on a per-particle basis. The laws help reconcile the disparities between field observations and model predictions. Our framework is packaged in an open-source Python application.
Kevin Cheuk Hang Sze, Heike Wex, Markus Hartmann, Henrik Skov, Andreas Massling, Diego Villanueva, and Frank Stratmann
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-761, https://doi.org/10.5194/acp-2022-761, 2022
Revised manuscript accepted for ACP
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Ice nucleating particles (INPs) play an important role in cloud formation, thus on our climate. But little is known about the abundance and properties of INPs, especially in the Arctic, where the temperature increases almost four times as fast as that of the rest of the globe. We observe higher INP concentrations and more biological INPs in summer than in winter, likely from local sources. We also provide three equations for estimating INP concentration in models at different times of the year.
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.
Guangyu Li, Jörg Wieder, Julie T. Pasquier, Jan Henneberger, and Zamin A. Kanji
Atmos. Chem. Phys., 22, 14441–14454, https://doi.org/10.5194/acp-22-14441-2022, https://doi.org/10.5194/acp-22-14441-2022, 2022
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The concentration of ice-nucleating particles (INPs) is atmospherically relevant for primary ice formation in clouds. In this work, from 12 weeks of field measurement data in the Arctic, we developed a new parameterization to predict INP concentrations applicable for pristine background conditions based only on temperature. The INP parameterization could improve the cloud microphysical representation in climate models, aiding in Arctic climate predictions.
Yuying Wang, Rong Hu, Qiuyan Wang, Zhanqing Li, Maureen Cribb, Yele Sun, Xiaorui Song, Yi Shang, Yixuan Wu, Xin Huang, and Yuxiang Wang
Atmos. Chem. Phys., 22, 14133–14146, https://doi.org/10.5194/acp-22-14133-2022, https://doi.org/10.5194/acp-22-14133-2022, 2022
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The mixing state of size-resolved soot particles and their influencing factors were investigated. The results suggest anthropogenic emissions and aging processes have diverse impacts on the mixing state of soot particles in different modes. Considering that the mixing state of soot particles is crucial to model aerosol absorption, this finding is important to study particle growth and the warming effect of black carbon aerosols.
Xiaoying Niu, Wei Pu, Pingqing Fu, Yang Chen, Yuxuan Xing, Dongyou Wu, Ziqi Chen, Tenglong Shi, Yue Zhou, Hui Wen, and Xin Wang
Atmos. Chem. Phys., 22, 14075–14094, https://doi.org/10.5194/acp-22-14075-2022, https://doi.org/10.5194/acp-22-14075-2022, 2022
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In this study, we do the first investigation of WSOC in seasonal snow of northeastern China. The results revealed the regional-specific compositions and sources of WSOC due to different natural environments and anthropogenic activities. The abundant concentrations of WSOC and its absorption properties contributed to a crucial impact on the snow albedo and radiative effect. We established that our study could raise awareness of carbon cycling processes, hydrological processes, and climate change.
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
Qian Liu, Guixing Chen, Lifang Sheng, and Toshiki Iwasaki
Atmos. Chem. Phys., 22, 13371–13388, https://doi.org/10.5194/acp-22-13371-2022, https://doi.org/10.5194/acp-22-13371-2022, 2022
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Air pollution can be cleaned up quickly by a cold air outbreak (CAO) but reappears after a CAO. By quantifying the CAO properties, we find the coldness and depth of the cold air mass are key factors affecting the rapid (slow) reappearance of air pollution through modulating the atmospheric boundary layer height and stability. We also find that the spatial pattern of CAO in high-latitude Eurasia a few days ahead can be recognized as a precursor for the reappearance of air pollution.
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.
Timothy Jiang, Mark Gordon, Paul A. Makar, Ralf M. Staebler, and Michael Wheeler
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-656, https://doi.org/10.5194/acp-2022-656, 2022
Revised manuscript accepted for ACP
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Measurements of sub-micron aerosols (small particles of size less than 1/1000 of a mm) were made in a forest downwind of oil sands mining and production facilities in northern Alberta. These measurements tell us how quickly aerosols are absorbed by the forest (known as deposition rate) and how the deposition rate depends on the size of the aerosol. The measurements show good agreement with a parameterization developed from a recent study for deposition of aerosols to a similar pine forest.
Eva-Lou Edwards, Jeffrey S. Reid, Peng Xian, Sharon P. Burton, Anthony L. Cook, Ewan C. Crosbie, Marta A. Fenn, Richard A. Ferrare, Sean W. Freeman, John W. Hair, David B. Harper, Chris A. Hostetler, Claire E. Robinson, Amy Jo Scarino, Michael A. Shook, G. Alexander Sokolowsky, Susan C. van den Heever, Edward L. Winstead, Sarah Woods, Luke D. Ziemba, and Armin Sorooshian
Atmos. Chem. Phys., 22, 12961–12983, https://doi.org/10.5194/acp-22-12961-2022, https://doi.org/10.5194/acp-22-12961-2022, 2022
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This study compares NAAPS-RA model simulations of aerosol optical thickness (AOT) and extinction to those retrieved with a high spectral resolution lidar near the Philippines. Agreement for AOT was good, and extinction agreement was strongest below 1500 m. Substituting dropsonde relative humidities into NAAPS-RA did not drastically improve agreement, and we discuss potential reasons why. Accurately modeling future conditions in this region is crucial due to its susceptibility to climate change.
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.
Nicole A. June, Anna L. Hodshire, Elizabeth B. Wiggins, Edward L. Winstead, Claire E. Robinson, K. Lee Thornhill, Kevin J. Sanchez, Richard H. Moore, Demetrios Pagonis, Hongyu Guo, Pedro Campuzano-Jost, Jose L. Jimenez, Matthew M. Coggon, Jonathan M. Dean-Day, T. Paul Bui, Jeff Peischl, Robert J. Yokelson, Matthew J. Alvarado, Sonia M. Kreidenweis, Shantanu H. Jathar, and Jeffrey R. Pierce
Atmos. Chem. Phys., 22, 12803–12825, https://doi.org/10.5194/acp-22-12803-2022, https://doi.org/10.5194/acp-22-12803-2022, 2022
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The evolution of organic aerosol composition and size is uncertain due to variability within and between smoke plumes. We examine the impact of plume concentration on smoke evolution from smoke plumes sampled by the NASA DC-8 during FIREX-AQ. We find that observed organic aerosol and size distribution changes are correlated to plume aerosol mass concentrations. Additionally, coagulation explains the majority of the observed growth.
Francesca Gallo, Janek Uin, Kevin J. Sanchez, Richard H. Moore, Jian Wang, Robert Wood, Fan Mei, Connor Flynn, Stephen Springston, Eduardo B. Azevedo, Chongai Kuang, and Allison C. Aiken
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-637, https://doi.org/10.5194/acp-2022-637, 2022
Revised manuscript accepted for ACP
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This study provides a summary statistic of multiday aerosol plume transport events influences on aerosol physical properties and cloud condensation nuclei budget at the U.S. Department of Energy Atmospheric Radiation Measurement Facility in the Eastern North Atlantic (ENA). An algorithm that integrates aerosol properties is developed and applied to identify multiday aerosol transport events. The influence of the aerosol plumes on aerosol populations at ENA is successively assessed.
Ruiqi Man, Zhijun Wu, Taomou Zong, Aristeidis Voliotis, Yanting Qiu, Johannes Größ, Dominik van Pinxteren, Limin Zeng, Hartmut Herrmann, Alfred Wiedensohler, and Min Hu
Atmos. Chem. Phys., 22, 12387–12399, https://doi.org/10.5194/acp-22-12387-2022, https://doi.org/10.5194/acp-22-12387-2022, 2022
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Regional and total deposition doses for different age groups were quantified based on explicit hygroscopicity measurements. We found that particle hygroscopic growth led to a reduction (~24 %) in the total dose. The deposition rate of hygroscopic particles was higher in the daytime, while hydrophobic particles exhibited a higher rate at night and during rush hours. The results will deepen the understanding of the impact of hygroscopicity and the mixing state on deposition patterns in the lungs.
Biao Luo, Ye Kuang, Shan Huang, Qicong Song, Weiwei Hu, Wei Li, Yuwen Peng, Duohong Chen, Dingli Yue, Bin Yuan, and Min Shao
Atmos. Chem. Phys., 22, 12401–12415, https://doi.org/10.5194/acp-22-12401-2022, https://doi.org/10.5194/acp-22-12401-2022, 2022
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We performed comprehensive analysis on biomass burning organic aerosol (BBOA) size distributions, as well as mass scattering and absorption efficiencies, with an improved method of on-line quantification of brown carbon absorptions. Both BBOA volume size distribution and retrieved refractive index depend highly on combustion conditions represented by the black carbon content, which has significant implications for BBOA climate effect simulations.
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.
Ruhi S. Humphries, Melita D. Keywood, Jason P. Ward, James Harnwell, Simon P. Alexander, Andrew R. Klekociuk, Keiichiro Hara, Ian M. McRobert, Alain Protat, Joel Alroe, Luke T. Cravigan, Branka Miljevic, Zoran D. Ristovski, Robyn Schofield, Stephen R. Wilson, Connor J. Flynn, Gourihar R. Kulkarni, Gerald G. Mace, Greg M. McFarquhar, Scott D. Chambers, Alastair G. Williams, and Alan D. Griffiths
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-568, https://doi.org/10.5194/acp-2022-568, 2022
Revised manuscript accepted for ACP
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Observations of aerosols in pristine regions are rare, but are vital to constraining the natural baseline from which climate simulations are calculated. Here we present recent seasonal observations of aerosols from the Southern Ocean and contrast them with measurements from Antarctica, Australia, and regionally relevant voyages. Strong seasonal cycles persist, but striking differences occur at different latitudes. This study highlights the need for more long-term observations in remote regions.
Samuel E. LeBlanc, Michal Segal-Rozenhaimer, Jens Redemann, Connor Flynn, Roy R. Johnson, Stephen E. Dunagan, Robert Dahlgren, Jhoon Kim, Myungje Choi, Arlindo da Silva, Patricia Castellanos, Qian Tan, Luke Ziemba, Kenneth Lee Thornhill, and Meloë Kacenelenbogen
Atmos. Chem. Phys., 22, 11275–11304, https://doi.org/10.5194/acp-22-11275-2022, https://doi.org/10.5194/acp-22-11275-2022, 2022
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Airborne observations of atmospheric particles and pollution over Korea during a field campaign in May–June 2016 showed that the smallest atmospheric particles are present in the lowest 2 km of the atmosphere. The aerosol size is more spatially variable than optical thickness. We show this with remote sensing (4STAR), in situ (LARGE) observations, satellite measurements (GOCI), and modeled properties (MERRA-2), and it is contrary to the current understanding.
Jerome D. Fast, David M. Bell, Gourihar Kulkarni, Jiumeng Liu, Fan Mei, Georges Saliba, John E. Shilling, Kaitlyn Suski, Jason Tomlinson, Jian Wang, Rahul Zaveri, and Alla Zelenyuk
Atmos. Chem. Phys., 22, 11217–11238, https://doi.org/10.5194/acp-22-11217-2022, https://doi.org/10.5194/acp-22-11217-2022, 2022
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Recent aircraft measurements from the HI-SCALE campaign conducted over the Southern Great Plains (SGP) site in Oklahoma are used to quantify spatial variability of aerosol properties in terms of grid spacings typically used by weather and climate models. Surprisingly large horizontal gradients in aerosol properties were frequently observed in this rural area. This spatial variability can be used as an uncertainty range when comparing surface point measurements with model predictions.
Jingye Ren, Fang Zhang, Lu Chen, and Jieyao Liu
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-542, https://doi.org/10.5194/acp-2022-542, 2022
Revised manuscript accepted for ACP
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The effective density of BC is closely linked to its morphology and mixing state and could cause uncertainty in evaluating CCN activity. We develop a new method to retrieve the mixing state and effective density of BC in urban atmosphere. We find that the mean retried density of internal-mixed BC was lower than the value assuming void-free spherical structures. Our study suggests the importance of accounting for varying BC density in models when assessing its climate effect in urban atmosphere.
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.
Gang Zhao, Tianyi Tan, Shuya Hu, Zhuofei Du, Dongjie Shang, Zhijun Wu, Song Guo, Jing Zheng, Wenfei Zhu, Mengren Li, Limin Zeng, and Min Hu
Atmos. Chem. Phys., 22, 10861–10873, https://doi.org/10.5194/acp-22-10861-2022, https://doi.org/10.5194/acp-22-10861-2022, 2022
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Black carbon is the second strongest absorbing component in the atmosphere that exerts warming effects on climate. One critical challenge in quantifying the ambient black carbon's radiative effects is addressing the BC microphysical properties. In this study, the microphysical properties of the aged and fresh BC particles are synthetically analyzed under different atmospheres. The measurement results can be further used in models to help constrain the uncertainties of the BC radiative effects.
Natalia E. Chubarova, Heike Vogel, Elizaveta E. Androsova, Alexander A. Kirsanov, Olga B. Popovicheva, Bernhard Vogel, and Gdaliy S. Rivin
Atmos. Chem. Phys., 22, 10443–10466, https://doi.org/10.5194/acp-22-10443-2022, https://doi.org/10.5194/acp-22-10443-2022, 2022
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Effects of urban aerosol pollution in Moscow were analyzed using the COSMO-ART chemical transport model and intensive measurement campaigns. We show that urban aerosol comprises about 15–20% of columnar aerosol content, consisting mainly of fine aerosol mode. The black carbon (BC) fraction is about 5 %, depending on particle dispersion intensity (IPD). The BC fraction low value explains weak absorbing properties of the Moscow atmosphere. IPD also defines the daily cycle of urban aerosol species.
Janine Lückerath, Andreas Held, Holger Siebert, Michel Michalkow, and Birgit Wehner
Atmos. Chem. Phys., 22, 10007–10021, https://doi.org/10.5194/acp-22-10007-2022, https://doi.org/10.5194/acp-22-10007-2022, 2022
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Three different methods were applied to estimate the vertical aerosol particle flux in the marine boundary layer (MBL) and between the MBL and free troposphere. For the first time, aerosol fluxes derived from these three methods were estimated and compared using airborne aerosol measurements using data from the ACORES field campaign in the northeastern Atlantic Ocean in July 2017. The amount of fluxes was small and directed up and down for different cases, but the methods were applicable.
Christian Tatzelt, Silvia Henning, André Welti, Andrea Baccarini, Markus Hartmann, Martin Gysel-Beer, Manuela van Pinxteren, Robin L. Modini, Julia Schmale, and Frank Stratmann
Atmos. Chem. Phys., 22, 9721–9745, https://doi.org/10.5194/acp-22-9721-2022, https://doi.org/10.5194/acp-22-9721-2022, 2022
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We present the abundance and origin of cloud-relevant aerosol particles in the preindustral-like conditions of the Southern Ocean (SO) during austral summer. Cloud condensation nuclei (CCN) and ice-nucleating particles (INP) were measured during a circum-Antarctic scientific cruise with in situ instrumentation and offline filter measurements, respectively. Transport processes were found to play an equally important role as local sources for both the CCN and INP population of the SO.
Alexander D. Harrison, Daniel O'Sullivan, Michael P. Adams, Grace C. E. Porter, Edmund Blades, Cherise Brathwaite, Rebecca Chewitt-Lucas, Cassandra Gaston, Rachel Hawker, Ovid O. Krüger, Leslie Neve, Mira L. Pöhlker, Christopher Pöhlker, Ulrich Pöschl, Alberto Sanchez-Marroquin, Andrea Sealy, Peter Sealy, Mark D. Tarn, Shanice Whitehall, James B. McQuaid, Kenneth S. Carslaw, Joseph M. Prospero, and Benjamin J. Murray
Atmos. Chem. Phys., 22, 9663–9680, https://doi.org/10.5194/acp-22-9663-2022, https://doi.org/10.5194/acp-22-9663-2022, 2022
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The formation of ice in clouds fundamentally alters cloud properties; hence it is important we understand the special aerosol particles that can nucleate ice when immersed in supercooled cloud droplets. In this paper we show that African desert dust that has travelled across the Atlantic to the Caribbean nucleates ice much less well than we might have expected.
Caroline Dang, Michal Segal-Rozenhaimer, Haochi Che, Lu Zhang, Paola Formenti, Jonathan Taylor, Amie Dobracki, Sara Purdue, Pui-Shan Wong, Athanasios Nenes, Arthur Sedlacek III, Hugh Coe, Jens Redemann, Paquita Zuidema, Steven Howell, and James Haywood
Atmos. Chem. Phys., 22, 9389–9412, https://doi.org/10.5194/acp-22-9389-2022, https://doi.org/10.5194/acp-22-9389-2022, 2022
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Transmission electron microscopy was used to analyze aged African smoke particles and how the smoke interacts with the marine atmosphere. We found that the volatility of organic aerosol increases with biomass burning plume age, that black carbon is often mixed with potassium salts and that the marine atmosphere can incorporate Na and Cl into smoke particles. Marine salts are more processed when mixed with smoke plumes, and there are interesting Cl-rich yet Na-absent marine particles.
Siman Ren, Lei Yao, Yuwei Wang, Gan Yang, Yiliang Liu, Yueyang Li, Yiqun Lu, Lihong Wang, and Lin Wang
Atmos. Chem. Phys., 22, 9283–9297, https://doi.org/10.5194/acp-22-9283-2022, https://doi.org/10.5194/acp-22-9283-2022, 2022
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We improved the empirical functions between volatility and chemical formulas of organic aerosols based on lab experiments and field observations. It was found that organic compounds in ambient aerosols can be divided into two groups according to their O / C ratios and that there should be specialized volatility parameterizations for different O / C organic compounds.
Lu Zhang, Michal Segal-Rozenhaimer, Haochi Che, Caroline Dang, Arthur J. Sedlacek III, Ernie R. Lewis, Amie Dobracki, Jenny P. S. Wong, Paola Formenti, Steven G. Howell, and Athanasios Nenes
Atmos. Chem. Phys., 22, 9199–9213, https://doi.org/10.5194/acp-22-9199-2022, https://doi.org/10.5194/acp-22-9199-2022, 2022
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Widespread biomass burning (BB) events occur annually in Africa and contribute ~ 1 / 3 of global BB emissions, which contain a large family of light-absorbing organics, known as brown carbon (BrC), whose absorption of incident radiation is difficult to estimate, leading to large uncertainties in the global radiative forcing estimation. This study quantifies the BrC absorption of aged BB particles and highlights the potential presence of absorbing iron oxides in this climatically important region.
Karin Ardon-Dryer and Mary C. Kelley
Atmos. Chem. Phys., 22, 9161–9173, https://doi.org/10.5194/acp-22-9161-2022, https://doi.org/10.5194/acp-22-9161-2022, 2022
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Changes in the particle size distribution and particulate matter concentrations during different dust events in West Texas were examined. Analysis based on different timescales showed that current common methods used to evaluate the impact of dust events on air quality will not capture the true impact of short (convective) dust events and, therefore, do not provide an insightful understanding of their impact on the environment and human health.
Chaman Gul, Shichang Kang, Siva Praveen Puppala, Xiaokang Wu, Cenlin He, Yangyang Xu, Inka Koch, Sher Muhammad, Rajesh Kumar, and Getachew Dubache
Atmos. Chem. Phys., 22, 8725–8737, https://doi.org/10.5194/acp-22-8725-2022, https://doi.org/10.5194/acp-22-8725-2022, 2022
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This work aims to understand concentrations, spatial variability, and potential source regions of light-absorbing impurities (black carbon aerosols, dust particles, and organic carbon) in the surface snow of central and western Himalayan glaciers and their impact on snow albedo and radiative forcing.
Haochi Che, Michal Segal-Rozenhaimer, Lu Zhang, Caroline Dang, Paquita Zuidema, Arthur J. Sedlacek III, Xiaoye Zhang, and Connor Flynn
Atmos. Chem. Phys., 22, 8767–8785, https://doi.org/10.5194/acp-22-8767-2022, https://doi.org/10.5194/acp-22-8767-2022, 2022
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A 17-month in situ study on Ascension Island found low single-scattering albedo and strong absorption enhancement of the marine boundary layer aerosols during biomass burnings on the African continent, along with apparent patterns of regular monthly variability. We further discuss the characteristics and drivers behind these changes and find that biomass burning conditions in Africa may be the main factor influencing the optical properties of marine boundary aerosols.
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Short summary
The study focuses mainly on cloud-scavenging efficiency of absorbing particulate matter (mainly black carbon) but additionally covers cloud-scavenging efficiency of scattering particles and statistics of cloud condensation nuclei. The main findings give insight into how black carbon is distributed in different particle sizes and the sensitivity to cloud scavenged. The main findings are useful for large-scale modelling for evaluating cloud scavenging.
The study focuses mainly on cloud-scavenging efficiency of absorbing particulate matter (mainly...
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