Articles | Volume 15, issue 2
23 Jan 2015
Research article | 23 Jan 2015
A comparison of HONO budgets for two measurement heights at a field station within the boreal forest in Finland
R. Oswald et al.
K. Hens, A. Novelli, M. Martinez, J. Auld, R. Axinte, B. Bohn, H. Fischer, P. Keronen, D. Kubistin, A. C. Nölscher, R. Oswald, P. Paasonen, T. Petäjä, E. Regelin, R. Sander, V. Sinha, M. Sipilä, D. Taraborrelli, C. Tatum Ernest, J. Williams, J. Lelieveld, and H. Harder
Atmos. Chem. Phys., 14, 8723–8747,
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,Short summary
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.
Laura Tomsche, Andreas Marsing, Tina Jurkat-Witschas, Johannes Lucke, Stefan Kaufmann, Katharina Kaiser, Johannes Schneider, Monika Scheibe, Hans Schlager, Lenard Röder, Horst Fischer, Florian Obersteiner, Andreas Zahn, Martin Zöger, Jos Lelieveld, and Christiane Voigt
Atmos. Chem. Phys., 22, 15135–15151,Short summary
The detection of sulfur compounds in the upper troposphere (UT) and lower stratosphere (LS) is a challenge. In-flight measurements of SO2 and sulfate aerosol were performed during the BLUESKY mission in spring 2020 under exceptional atmospheric conditions. Reduced sinks in the dry UTLS and lower but still significant air traffic influenced the enhanced SO2 in the UT, and aged volcanic plumes enhanced the LS sulfate aerosol impacting the atmospheric radiation budget and global climate.
Lenard L. Röder, Patrick Dewald, Clara M. Nussbaumer, Jan Schuladen, John N. Crowley, Jos Lelieveld, and Horst Fischer
This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).Short summary
Field experiments in atmospheric chemistry provide insights into chemical interactions of our atmosphere. However, high data coverage and accuracy is needed to enable further analysis. In this study we explore a statistical method that combines knowledge about the chemical reactions with information from measurements to increase the quality of field experiment data sets. We test the algorithm for several applications and discuss limitations that depend on the specific variable and the dynamics.
Lisa Ernle, Monika Akima Ringsdorf, and Jonathan Williams
Atmos. Meas. Tech. Discuss.,
Preprint under review for AMTShort summary
Atmospheric ozone can induce artifacts in volatile organic compound measurements. Laboratory tests were made using GC-MS and PTR-MS aircraft systems under tropospheric and stratospheric conditions of humidity and ozone, with and without sodium thiosulfate filter scrubbers. Ozone in dry air produces some carbonyls and degrades alkenes. The scrubber lifetime depends on ozone concentration, flow rate and humidity. For the troposphere with scrubber, no significant artifacts were found over 14 days.
Rujing Yin, Xiaoxiao Li, Chao Yan, Runlong Cai, Ying Zhou, Juha Kangasluoma, Nina Sarnela, Janne Lampilahti, Tuukka Petäjä, Veli-Matti Kerminen, Federico Bianchi, Markku Kulmala, and Jingkun Jiang
The negative cluster ions with specific compositions are measured and quantified through the in-situ measurement of an atmospheric pressure interface high-resolution time-of-flight mass spectrometer and a neutral cluster and air ion spectrometer in urban Beijing. The governing factors of atmospheric negative cluster ion concentration and composition at polluted urban sites are revealed and the fate of two representative ions in the urban atmosphere is characterized.
Kezia Lange, Andreas Richter, Anja Schönhardt, Andreas C. Meier, Tim Bösch, André Seyler, Kai Krause, Lisa K. Behrens, Folkard Wittrock, Alexis Merlaud, Frederik Tack, Caroline Fayt, Martina M. Friedrich, Ermioni Dimitropoulou, Michel Van Roozendael, Vinod Kumar, Sebastian Donner, Steffen Dörner, Bianca Lauster, Maria Razi, Christian Borger, Katharina Uhlmannsiek, Thomas Wagner, Thomas Ruhtz, Henk Eskes, Birger Bohn, Daniel Santana Diaz, Nader Abuhassan, Dirk Schüttemeyer, and John P. Burrows
Atmos. Meas. Tech. Discuss.,
Preprint under review for AMTShort summary
We present airborne imaging DOAS, ground-based stationary and car DOAS measurements conducted during the S5P-VAL-DE-Ruhr campaign in the Rhine-Ruhr region. The measurements are used to validate space-borne NO2 data products from the Sentinel-5 Precursor TROPOspheric Monitoring Instrument (TROPOMI). Auxiliary data of the TROPOMI NO2 retrieval, such as spatially higher resolved a priori NO2 vertical profiles, surface reflectivity and the cloud treatment are investigated to evaluate their impact.
Birger Bohn and Insa Lohse
Atmos. Meas. Tech. Discuss.,
Preprint under review for AMTShort summary
Optical receivers for solar spectral actinic radiation are designed for angle-independent sensitivities within a hemisphere. Remaining imperfections can be compensated by receiver-specific corrections based on laboratory characterizations and radiative transfer calculations of spectral radiance distributions. The corrections cover a wide range of realistic atmospheric conditions and were applied to ground-based and airborne measurements in a wavelength range 280–660 nm.
Zaneta Hamryszczak, Dirk Dienhart, Bettina Brendel, Roland Rohloff, Daniel Marno, Monica Martinez, Hartwig Harder, Andrea Pozzer, Birger Bohn, Martin Zöger, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
Hydrogen peroxide is a key contributor to the oxidative chemistry of the atmosphere through its link to the most prominent oxidants controlling its self-cleansing capacity, HOx. During CAFE-Africa campaign, H2O2 was measured over the Atlantic Ocean and western Africa in August/September 2018. The study gives an overview of the distribution of H2O2 in the upper tropical troposphere and investigates the impact of convective processes in the Intertropical Convergence Zone on the budget of H2O2.
Peter Bergamaschi, Arjo Segers, Dominik Brunner, Jean-Matthieu Haussaire, Stephan Henne, Michel Ramonet, Tim Arnold, Tobias Biermann, Huilin Chen, Sebastien Conil, Marc Delmotte, Grant Forster, Arnoud Frumau, Dagmar Kubistin, Xin Lan, Markus Leuenberger, Matthias Lindauer, Morgan Lopez, Giovanni Manca, Jennifer Müller-Williams, Simon O'Doherty, Bert Scheeren, Martin Steinbacher, Pamela Trisolino, Gabriela Vítková, and Camille Yver Kwok
Atmos. Chem. Phys., 22, 13243–13268,Short summary
We present a novel high-resolution inverse modelling system, "FLEXVAR", and its application for the inverse modelling of European CH4 emissions in 2018. The new system combines a high spatial resolution of 7 km x 7 km with a variational data assimilation technique, which allows CH4 emissions to be optimized from individual model grid cells. The high resolution allows the observations to be better reproduced, while the derived emissions show overall good consistency with two existing models.
Zhaofeng Tan, Hendrik Fuchs, Andreas Hofzumahaus, William J. Bloss, Birger Bohn, Changmin Cho, Thorsten Hohaus, Frank Holland, Chandrakiran Lakshmisha, Lu Liu, Paul S. Monks, Anna Novelli, Doreen Niether, Franz Rohrer, Ralf Tillmann, Thalassa S. E. Valkenburg, Vaishali Vardhan, Astrid Kiendler-Scharr, Andreas Wahner, and Roberto Sommariva
Atmos. Chem. Phys., 22, 13137–13152,Short summary
During the 2019 JULIAC campaign, ClNO2 was measured at a rural site in Germany in different seasons. The highest ClNO2 level was 1.6 ppbv in September. ClNO2 production was more sensitive to the availability of NO2 than O3. The average ClNO2 production efficiency was up to 18 % in February and September and down to 3 % in December. These numbers are at the high end of the values reported in the literature, indicating the importance of ClNO2 chemistry in rural environments in midwestern Europe.
Dominik Stolzenburg, Tiia Laurila, Pasi Aalto, Joonas Vanhanen, Tuukka Petäjä, and Juha Kangasluoma
Atmos. Meas. Tech. Discuss.,
Preprint under review for AMTShort summary
Size-distributions measurements of ultrafine particles are of special interest as they can be used to estimate the atmospheric signficance of new particle formation, a process which is thought to influence the global climate. Here we show that improved counting statistics in size-distribution measurements through the usage of higher sampling flows can significantly reduce the uncertainties in such calculations.
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,Short summary
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.
Charlotte M. Beall, Thomas C. J. Hill, Paul J. DeMott, Tobias Köneman, Michael Pikridas, Frank Drewnick, Hartwig Harder, Christopher Pöhlker, Jos Lelieveld, Bettina Weber, Minas Iakovides, Roman Prokeš, Jean Sciare, Meinrat O. Andreae, M. Dale Stokes, and Kimberly A. Prather
Atmos. Chem. Phys., 22, 12607–12627,Short summary
Ice-nucleating particles (INPs) are rare aerosols that can trigger ice formation in clouds and affect climate-relevant cloud properties such as phase, reflectivity and lifetime. Dust is the dominant INP source, yet few measurements have been reported near major dust sources. We report INP observations within hundreds of kilometers of the biggest dust source regions globally: the Sahara and the Arabian Peninsula. Results show that at temperatures > −15 °C, INPs are dominated by organics.
Mengze Li, Andrea Pozzer, Jos Lelieveld, and Jonathan Williams
Earth Syst. Sci. Data, 14, 4351–4364,Short summary
We present a northern hemispheric airborne measurement dataset of atmospheric ethane, propane and methane and temporal trends for the time period 2006–2016 in the upper troposphere and lower stratosphere. The growth rates of ethane, methane, and propane in the upper troposphere are -2.24, 0.33, and -0.78 % yr-1, respectively, and in the lower stratosphere they are -3.27, 0.26, and -4.91 % yr-1, respectively, in 2006–2016.
Chao Yan, Yicheng Shen, Dominik Stolzenburg, Lubna Dada, Ximeng Qi, Simo Hakala, Anu-Maija Sundström, Yishuo Guo, Antti Lipponen, Tom V. Kokkonen, Jenni Kontkanen, Runlong Cai, Jing Cai, Tommy Chan, Liangduo Chen, Biwu Chu, Chenjuan Deng, Wei Du, Xiaolong Fan, Xu-Cheng He, Juha Kangasluoma, Joni Kujansuu, Mona Kurppa, Chang Li, Yiran Li, Zhuohui Lin, Yiliang Liu, Yuliang Liu, Yiqun Lu, Wei Nie, Jouni Pulliainen, Xiaohui Qiao, Yonghong Wang, Yifan Wen, Ye Wu, Gan Yang, Lei Yao, Rujing Yin, Gen Zhang, Shaojun Zhang, Feixue Zheng, Ying Zhou, Antti Arola, Johanna Tamminen, Pauli Paasonen, Yele Sun, Lin Wang, Neil M. Donahue, Yongchun Liu, Federico Bianchi, Kaspar R. Daellenbach, Douglas R. Worsnop, Veli-Matti Kerminen, Tuukka Petäjä, Aijun Ding, Jingkun Jiang, and Markku Kulmala
Atmos. Chem. Phys., 22, 12207–12220,Short summary
Atmospheric new particle formation (NPF) is a dominant source of atmospheric ultrafine particles. In urban environments, traffic emissions are a major source of primary pollutants, but their contribution to NPF remains under debate. During the COVID-19 lockdown, traffic emissions were significantly reduced, providing a unique chance to examine their relevance to NPF. Based on our comprehensive measurements, we demonstrate that traffic emissions alone are not able to explain the NPF in Beijing.
Therese S. Carter, Colette L. Heald, Jesse H. Kroll, Eric C. Apel, Donald Blake, Matthew Coggon, Achim Edtbauer, Georgios Gkatzelis, Rebecca S. Hornbrook, Jeff Peischl, Eva Y. Pfannerstill, Felix Piel, Nina G. Reijrink, Akima Ringsdorf, Carsten Warneke, Jonathan Williams, Armin Wisthaler, and Lu Xu
Atmos. Chem. Phys., 22, 12093–12111,Short summary
Fires emit many gases which can contribute to smog and air pollution. However, the amount and properties of these chemicals are not well understood, so this work updates and expands their representation in a global atmospheric model, including by adding new chemicals. We confirm that this updated representation generally matches measurements taken in several fire regions. We then show that fires provide ~15 % of atmospheric reactivity globally and more than 75 % over fire source regions.
Sini Isokääntä, Paul Kim, Santtu Mikkonen, Thomas Kühn, Harri Kokkola, Taina Yli-Juuti, Liine Heikkinen, Krista Luoma, Tuukka Petäjä, Zak Kipling, Daniel Partridge, and Annele Virtanen
Atmos. Chem. Phys., 22, 11823–11843,Short summary
This research employs air mass history analysis and observations to study how clouds and precipitation affect atmospheric aerosols during transport to a boreal forest site. The mass concentrations of studied chemical species showed exponential decrease as a function of accumulated rain along the air mass route. Our analysis revealed in-cloud sulfate formation, while no major changes in organic mass were seen. Most of the in-cloud-formed sulfate could be assigned to particle sizes above 200 nm.
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,Short summary
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.
Changmin Cho, Hendrik Fuchs, Andreas Hofzumahaus, Frank Holland, William J. Bloss, Birger Bohn, Hans-Peter Dorn, Marvin Glowania, Thorsten Hohaus, Lu Liu, Paul S. Monks, Doreen Niether, Franz Rohrer, Roberto Sommariva, Zhaofeng Tan, Ralf Tillmann, Astrid Kiendler-Scharr, Andreas Wahner, and Anna Novelli
With this study, we investigated the processes leading to the formation, destruction, and recycling of radicals for four seasons in a rural environment. A complete knowledge of their chemistry is needed if we are to predict the formation of secondary pollutants from primary emissions. The results highlighted an incomplete understanding of the paths leading to the formation of the OH radical and that has been observed in several different environments and that needs to be investigated further.
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, Markku Kulmala, Tuukka Petäjä, Mikko Sipilä, Julia Schmale, and Tuija Jokinen
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
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, 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.
Simon F. Reifenberg, Anna Martin, Matthias Kohl, Sara Bacer, Zaneta Hamryszczak, Ivan Tadic, Lenard Röder, Daniel J. Crowley, Horst Fischer, Katharina Kaiser, Johannes Schneider, Raphael Dörich, John N. Crowley, Laura Tomsche, Andreas Marsing, Christiane Voigt, Andreas Zahn, Christopher Pöhlker, Bruna A. Holanda, Ovid Krüger, Ulrich Pöschl, Mira Pöhlker, Patrick Jöckel, Marcel Dorf, Ulrich Schumann, Jonathan Williams, Birger Bohn, Joachim Curtius, Hardwig Harder, Hans Schlager, Jos Lelieveld, and Andrea Pozzer
Atmos. Chem. Phys., 22, 10901–10917,Short summary
In this work we use a combination of observational data from an aircraft campaign and model results to investigate the effect of the European lockdown due to COVID-19 in spring 2020. Using model results, we show that the largest relative changes to the atmospheric composition caused by the reduced emissions are located in the upper troposphere around aircraft cruise altitude, while the largest absolute changes are present at the surface.
Lucía Caudillo, Mihnea Surdu, Brandon Lopez, Mingyi Wang, Markus Thoma, Steffen Bräkling, Angela Buchholz, Mario Simon, Andrea C. Wagner, Tatjana Müller, Manuel Granzin, Martin Heinritzi, Antonio Amorim, David M. Bell, Zoé Brasseur, Lubna Dada, Jonathan Duplissy, Henning Finkenzeller, Xu-Cheng He, Houssni Lamkaddam, Naser G. A. Mahfouz, Vladimir Makhmutov, Hanna E. Manninen, Guillaume Marie, Ruby Marten, Roy L. Mauldin, Bernhard Mentler, Antti Onnela, Tuukka Petäjä, Joschka Pfeifer, Maxim Philippov, Ana A. Piedehierro, Birte Rörup, Wiebke Scholz, Jiali Shen, Dominik Stolzenburg, Christian Tauber, Ping Tian, António Tomé, Nsikanabasi Silas Umo, Dongyu S. Wang, Yonghong Wang, Stefan K. Weber, André Welti, Marcel Zauner-Wieczorek, Urs Baltensperger, Richard C. Flagan, Armin Hansel, Jasper Kirkby, Markku Kulmala, Katrianne Lehtipalo, Douglas R. Worsnop, Imad El Haddad, Neil M. Donahue, Alexander L. Vogel, Andreas Kürten, and Joachim Curtius
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
In this study, we present an intercomparison study of four different techniques for measuring the chemical composition of nanoparticles. The intercomparison was performed based on the observed chemical composition, calculated volatility, and analysis of the thermograms. We found that the methods generally agree on the most important compounds that are found in the nanoparticles. However, they do see different parts of the organic spectrum. We suggest potential explanations for these differences.
Dirk Dienhart, Bettina Brendel, John N. Crowley, Philipp G. Eger, Hartwig Harder, Monica Martinez, Andrea Pozzer, Roland Rohloff, Jan Schuladen, Sebastian Tauer, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
Formaldehyde and hydroperoxide measurements were performed in the marine boundary layer around the Arabian Peninsula and highlight the Suez Canal and the Arabian (Persian) Gulf as a hotspot of photochemical air pollution. The comparison with the general circulation model EMAC shows rather accurate results of formaldehyde and an overestimation of hydrogen peroxide, which revealed enhanced HOx (=OH+HO2) radicals in the simulation and an underestimation of dry deposition velocites.
Jing Duan, Ru-Jin Huang, Yifang Gu, Chunshui Lin, Haobin Zhong, Wei Xu, Quan Liu, Yan You, Jurgita Ovadnevaite, Darius Ceburnis, Thorsten Hoffmann, and Colin O'Dowd
Atmos. Chem. Phys., 22, 10139–10153,Short summary
Biomass-burning-influenced oxygenated organic aerosol (OOA-BB), formed from the photochemical oxidation and aging of biomass burning OA (BBOA), was resolved in urban Xi’an. The aqueous-phase processed oxygenated OA (aq-OOA) concentration was more dependent on secondary inorganic aerosol (SIA) content and aerosol liquid water content (ALWC). The increased aq-OOA contribution during SIA-enhanced periods likely reflects OA evolution due to the addition of alcohol or peroxide groups
Chuan-Yao Lin, Wan-Chin Chen, Yi-Yun Chien, Charles C. K. Chou, Chian-Yi Liu, Helmut Ziereis, Hans Schlager, Eric Förster, Florian Obersteiner, Ovid O. Krüger, Bruna A. Holanda, Mira L. Pöhlker, Katharina Kaiser, Johannes Schneider, Birger Bohn, Maria Dolores Andrés Hernández, and John P. Burrows
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
During the EMeRGe campaign in Asia, atmospheric pollutants were measured on board the HALO aircraft. The WRF-Chem model was employed to evaluate the BB plume transported from Indochina and its impact on the downstream areas. The combination of BB aerosol enhancement with cloud water resulted in a reduction of incoming shortwave radiation at the surface in South China and the East China Sea which potentially has significant regional climate implications.
Yunfan Liu, Hang Su, Siwen Wang, Chao Wei, Wei Tao, Mira L. Pöhlker, Christopher Pöhlker, Bruna A. Holanda, Ovid O. Krüger, Thorsten Hoffmann, Manfred Wendisch, Paulo Artaxo, Ulrich Pöschl, Meinrat O. Andreae, and Yafang Cheng
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
The origins of the abundant cloud condensation nuclei (CCN) in the upper troposphere (UT) of the Amazon remain unclear. With model developments of new secondary organic aerosol schemes and constrained by observation, we show that the UT aerosol formation triggered by biogenic organics shapes the UT aerosols, and organic condensation is key for UT CCN production. This UT CCN-producing mechanism may prevail over broader vegetation canopies and deserves emphasis in aerosol-climate feedback.
Carlton Xavier, Metin Baykara, Robin Wollesen de Jonge, Barbara Altstädter, Petri Clusius, Ville Vakkari, Roseline Thakur, Lisa Beck, Silvia Becagli, Mirko Severi, Rita Traversi, Radovan Krejci, Peter Tunved, Mauro Mazzola, Birgit Wehner, Mikko Sipilä, Markku Kulmala, Michael Boy, and Pontus Roldin
Atmos. Chem. Phys., 22, 10023–10043,Short summary
The focus of this work is to study and improve our understanding of processes involved in the formation and growth of new particles in a remote Arctic marine environment. We run the 1D model ADCHEM along air mass trajectories arriving at Ny-Ålesund in May 2018. The model finds that ion-mediated H2SO4–NH3 nucleation can explain the observed new particle formation at Ny-Ålesund. The growth of particles is driven via H2SO4 condensation and formation of methane sulfonic acid in the aqueous phase.
Hannele Hakola, Ditte Taipale, Arnaud Praplan, Simon Schallhart, Steven Thomas, Toni Tykkä, Aku Helin, Jaana Bäck, and Heidi Hellén
Atmos. Chem. Phys. Discuss.,
Revised manuscript not acceptedShort summary
Norway spruce is one of the main tree species growing in the boreal area. We show that volatile organic compound emission potentials and compound composition vary a lot. We have investigated if e.g. growing location or age of a tree could explain the variations. Recognizing this observed large variability in spruce BVOC emissions (precursors for new particle formation processes), we also tested the consequences of this variability in simulations of aerosol formation.
Zaneta T. Hamryszczak, Andrea Pozzer, Florian Obersteiner, Birger Bohn, Benedikt Steil, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 22, 9483–9497,Short summary
Hydrogen peroxide plays a pivotal role in the chemistry of the atmosphere. Together with organic hydroperoxides, it forms a reservoir for peroxy radicals, which are known to be the key contributors to the self-cleaning processes of the atmosphere. Hydroperoxides were measured over Europe during the BLUESKY campaign in May–June 2020. The paper gives an overview of the distribution of the species in the troposphere and investigates the impact of wet scavenging and deposition on the budget of H2O2.
Ivo Beck, Hélène Angot, Andrea Baccarini, Lubna Dada, Lauriane Quéléver, Tuija Jokinen, Tiia Laurila, Markus Lampimäki, Nicolas Bukowiecki, Matthew Boyer, Xianda Gong, Martin Gysel-Beer, Tuukka Petäjä, Jian Wang, and Julia Schmale
Atmos. Meas. Tech., 15, 4195–4224,Short summary
We present the pollution detection algorithm (PDA), a new method to identify local primary pollution in remote atmospheric aerosol and trace gas time series. The PDA identifies periods of contaminated data and relies only on the target dataset itself; i.e., it is independent of ancillary data such as meteorological variables. The parameters of all pollution identification steps are adjustable so that the PDA can be tuned to different locations and situations. It is available as open-access code.
Philip T. M. Carlsson, Luc Vereecken, Anna Novelli, François Bernard, Steven S. Brown, Bellamy Brownwood, Changmin Cho, John N. Crowley, Patrick Dewald, Peter M. Edwards, Nils Friedrich, Juliane L. Fry, Mattias Hallquist, Luisa Hantschke, Thorsten Hohaus, Sungah Kang, Jonathan Liebmann, Alfred W. Mayhew, Thomas Mentel, David Reimer, Franz Rohrer, Justin Shenolikar, Ralf Tillmann, Epameinondas Tsiligiannis, Rongrong Wu, Andreas Wahner, Astrid Kiendler-Scharr, and Hendrik Fuchs
The investigation of the bight-time oxidation of the most abundant hydrocarbon, isoprene in chamber experiments shows the importance of so far unaccounted reaction pathways leading to epoxy products, which could enhance particle formation. The chemical lifetime of organic nitrates from isoprene is long enough that the majority will be further oxidized on the next by daytime oxidants.
Marco Wietzoreck, Marios Kyprianou, Benjamin A. Musa Bandowe, Siddika Celik, John N. Crowley, Frank Drewnick, Philipp Eger, Nils Friedrich, Minas Iakovides, Petr Kukučka, Jan Kuta, Barbora Nežiková, Petra Pokorná, Petra Přibylová, Roman Prokeš, Roland Rohloff, Ivan Tadic, Sebastian Tauer, Jake Wilson, Hartwig Harder, Jos Lelieveld, Ulrich Pöschl, Euripides G. Stephanou, and Gerhard Lammel
Atmos. Chem. Phys., 22, 8739–8766,Short summary
A unique dataset of concentrations and sources of polycyclic aromatic hydrocarbons (PAHs) and their alkylated, oxygenated and nitrated derivatives, in total 74 individual species, in the marine atmosphere is presented. Exposure to these substances poses a major health risk. We found very low concentrations over the Arabian Sea, while both local and long-range-transported pollution caused elevated levels over the Mediterranean Sea and the Arabian Gulf.
Lisa J. Beck, Siegfried Schobesberger, Heikki Junninen, Janne Lampilahti, Antti Manninen, Lubna Dada, Katri Leino, Xu-Cheng He, Iida Pullinen, Lauriane L. J. Quéléver, Anna Franck, Pyry Poutanen, Daniela Wimmer, Frans Korhonen, Mikko Sipilä, Mikael Ehn, Douglas R. Worsnop, Veli-Matti Kerminen, Tuukka Petäjä, Markku Kulmala, and Jonathan Duplissy
Atmos. Chem. Phys., 22, 8547–8577,Short summary
The presented article introduces an overview of atmospheric ions and their composition above the boreal forest. We provide the results of an extensive airborne measurement campaign with an air ion mass spectrometer and particle measurements, showing their diurnal evolution within the boundary layer and free troposphere. In addition, we compare the airborne dataset with the co-located data from the ground at SMEAR II station, Finland.
Karine Sartelet, Youngseob Kim, Florian Couvidat, Maik Merkel, Tuukka Petäjä, Jean Sciare, and Alfred Wiedensohler
Atmos. Chem. Phys., 22, 8579–8596,Short summary
A methodology is defined to estimate number emissions from an inventory providing mass emissions. Number concentrations are simulated over Greater Paris using different nucleation parameterisations (binary, ternary involving sulfuric acid and ammonia, and heteromolecular involving sulfuric acid and extremely low-volatility organics, ELVOCs). The comparisons show that ternary nucleation may not be a dominant process for new particle formation in cities, but they stress the role of ELVOCs.
Jacky Yat Sing Pang, Anna Novelli, Martin Kaminski, Ismail-Hakki Acir, Birger Bohn, Philip T. M. Carlsson, Changmin Cho, Hans-Peter Dorn, Andreas Hofzumahaus, Xin Li, Anna Lutz, Sascha Nehr, David Reimer, Franz Rohrer, Ralf Tillmann, Robert Wegener, Astrid Kiendler-Scharr, Andreas Wahner, and Hendrik Fuchs
Atmos. Chem. Phys., 22, 8497–8527,Short summary
This study investigates the radical chemical budget during the limonene oxidation at different atmospheric-relevant NO concentrations in chamber experiments under atmospheric conditions. It is found that the model–measurement discrepancies of HO2 and RO2 are very large at low NO concentrations that are typical for forested environments. Possible additional processes impacting HO2 and RO2 concentrations are discussed.
Lauriane L. J. Quéléver, Lubna Dada, Eija Asmi, Janne Lampilahti, Tommy Chan, Jonathan E. Ferrara, Gustavo E. Copes, German Pérez-Fogwill, Luis Barreira, Minna Aurela, Douglas R. Worsnop, Tuija Jokinen, and Mikko Sipilä
Atmos. Chem. Phys., 22, 8417–8437,Short summary
Understanding how aerosols form is crucial for correctly modeling the climate and improving future predictions. This work provides extensive analysis of aerosol particles and their precursors at Marambio Station, Antarctic Peninsula. We show that sulfuric acid, ammonia, and dimethylamine are key contributors to the frequent new particle formation events observed at the site. We discuss nucleation mechanisms and highlight the need for targeted measurement to fully understand these processes.
Miska Olin, Magdalena Okuljar, Matti P. Rissanen, Joni Kalliokoski, Jiali Shen, Lubna Dada, Markus Lampimäki, Yusheng Wu, Annalea Lohila, Jonathan Duplissy, Mikko Sipilä, Tuukka Petäjä, Markku Kulmala, and Miikka Dal Maso
Atmos. Chem. Phys., 22, 8097–8115,Short summary
Atmospheric new particle formation is an important source of the total particle number concentration in the atmosphere. Several parameters for predicting new particle formation events have been suggested before, but the results have been inconclusive. This study proposes an another predicting parameter, related to a specific type of highly oxidized organic molecules, especially for similar locations to the measurement site in this study, which was a coastal agricultural site in Finland.
Anton Rusanen, Kristo Hõrrak, Lauri R. Ahonen, Tuomo Nieminen, Pasi P. Aalto, Pasi Kolari, Markku Kulmala, Tuukka Petäjä, and Heikki Junninen
Atmos. Meas. Tech. Discuss.,
Preprint under review for AMTShort summary
We present a framework for setting up SMEAR (Station for Measuring Earth Surface-Atmosphere Relations) type measurement station data flows. This framework, called SMEARcore, consists of modular open-source software components that can be chosen to suit various station configurations. The benefits of using this framework are automation of routine operations, real-time monitoring of measurement results and station status.
Patrick Dewald, Clara M. Nussbaumer, Jan Schuladen, Akima Ringsdorf, Achim Edtbauer, Horst Fischer, Jonathan Williams, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 22, 7051–7069,Short summary
We measured the gas-phase reactivity of the NO3 radical on the summit (825 m a.s.l.) of a semi-rural mountain in southwestern Germany in July 2021. The impact of VOC-induced NO3 losses (mostly monoterpenes) competing with a loss by reaction with NO and photolysis throughout the diel cycle was estimated. Besides chemistry, boundary layer dynamics and plant-physiological processes presumably have a great impact on our observations, which were compared to previous NO3 measurements at the same site.
Roseline C. Thakur, Lubna Dada, Lisa J. Beck, Lauriane L. J. Quéléver, Tommy Chan, Marjan Marbouti, Xu-Cheng He, Carlton Xavier, Juha Sulo, Janne Lampilahti, Markus Lampimäki, Yee Jun Tham, Nina Sarnela, Katrianne Lehtipalo, Alf Norkko, Markku Kulmala, Mikko Sipilä, and Tuija Jokinen
Atmos. Chem. Phys., 22, 6365–6391,Short summary
Every year intense cyanobacterial and macroalgal blooms occur in the Baltic Sea and in the coastal areas surrounding Helsinki, yet no studies have addressed the impact of biogenic emissions from these blooms on gas vapor concentrations, which in turn could influence new particle formation. This is the first study of its kind to address the chemistry driving new particle formation (NPF) during a bloom period in this region, highlighting the role of biogenic sulfuric acid and iodic acid.
Clara M. Nussbaumer, Andrea Pozzer, Ivan Tadic, Lenard Röder, Florian Obersteiner, Hartwig Harder, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 22, 6151–6165,Short summary
The European COVID-19 lockdowns have significantly reduced the emission of primary pollutants such as NOx, which impacts the tropospheric photochemical processes and the abundance of O3. In this study, we present how the lockdowns have affected tropospheric trace gases and ozone production based on in situ observations and modeling simulations. We additionally show that the chemical regime shifted from a transition point to a NOx limitation in the upper troposphere.
M. Dolores Andrés Hernández, Andreas Hilboll, Helmut Ziereis, Eric Förster, Ovid O. Krüger, Katharina Kaiser, Johannes Schneider, Francesca Barnaba, Mihalis Vrekoussis, Jörg Schmidt, Heidi Huntrieser, Anne-Marlene Blechschmidt, Midhun George, Vladyslav Nenakhov, Theresa Harlass, Bruna A. Holanda, Jennifer Wolf, Lisa Eirenschmalz, Marc Krebsbach, Mira L. Pöhlker, Anna B. Kalisz Hedegaard, Linlu Mei, Klaus Pfeilsticker, Yangzhuoran Liu, Ralf Koppmann, Hans Schlager, Birger Bohn, Ulrich Schumann, Andreas Richter, Benjamin Schreiner, Daniel Sauer, Robert Baumann, Mariano Mertens, Patrick Jöckel, Markus Kilian, Greta Stratmann, Christopher Pöhlker, Monica Campanelli, Marco Pandolfi, Michael Sicard, José L. Gómez-Amo, Manuel Pujadas, Katja Bigge, Flora Kluge, Anja Schwarz, Nikos Daskalakis, David Walter, Andreas Zahn, Ulrich Pöschl, Harald Bönisch, Stephan Borrmann, Ulrich Platt, and John P. Burrows
Atmos. Chem. Phys., 22, 5877–5924,Short summary
EMeRGe provides a unique set of in situ and remote sensing airborne measurements of trace gases and aerosol particles along selected flight routes in the lower troposphere over Europe. The interpretation uses also complementary collocated ground-based and satellite measurements. The collected data help to improve the current understanding of the complex spatial distribution of trace gases and aerosol particles resulting from mixing, transport, and transformation of pollution plumes over Europe.
Ruochong Xu, Joel A. Thornton, Ben H. Lee, Yanxu Zhang, Lyatt Jaeglé, Felipe D. Lopez-Hilfiker, Pekka Rantala, and Tuukka Petäjä
Atmos. Chem. Phys., 22, 5477–5494,Short summary
Monoterpenes are emitted into the atmosphere by vegetation and by the use of certain consumer products. Reactions of monoterpenes in the atmosphere lead to low-volatility products that condense to grow particulate matter or participate in new particle formation and, thus, affect air quality and climate. We use a model of atmospheric chemistry and transport to evaluate the global-scale importance of recent updates to our understanding of monoterpene chemistry in particle formation and growth.
Zoé Brasseur, Dimitri Castarède, Erik S. Thomson, Michael P. Adams, Saskia Drossaart van Dusseldorp, Paavo Heikkilä, Kimmo Korhonen, Janne Lampilahti, Mikhail Paramonov, Julia Schneider, Franziska Vogel, Yusheng Wu, Jonathan P. D. Abbatt, Nina S. Atanasova, Dennis H. Bamford, Barbara Bertozzi, Matthew Boyer, David Brus, Martin I. Daily, Romy Fösig, Ellen Gute, Alexander D. Harrison, Paula Hietala, Kristina Höhler, Zamin A. Kanji, Jorma Keskinen, Larissa Lacher, Markus Lampimäki, Janne Levula, Antti Manninen, Jens Nadolny, Maija Peltola, Grace C. E. Porter, Pyry Poutanen, Ulrike Proske, Tobias Schorr, Nsikanabasi Silas Umo, János Stenszky, Annele Virtanen, Dmitri Moisseev, Markku Kulmala, Benjamin J. Murray, Tuukka Petäjä, Ottmar Möhler, and Jonathan Duplissy
Atmos. Chem. Phys., 22, 5117–5145,Short summary
The present measurement report introduces the ice nucleation campaign organized in Hyytiälä, Finland, in 2018 (HyICE-2018). We provide an overview of the campaign settings, and we describe the measurement infrastructure and operating procedures used. In addition, we use results from ice nucleation instrument inter-comparison to show that the suite of these instruments deployed during the campaign reports consistent results.
Meri Räty, Larisa Sogacheva, Helmi-Marja Keskinen, Veli-Matti Kerminen, Tuomo Nieminen, Tuukka Petäjä, Ekaterina Ezhova, and Markku Kulmala
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
We utilised back-trajectories to identify the source region of air masses arriving in Hyytiälä, Finland, and their travel time over forests. Combined with atmospheric observations, they revealed how air mass transport over the Fennoscandian boreal forest during the growing season produced an accumulation of cloud condensation nuclei and humidity, promoting cloudiness and precipitation. By 60 hours of transport, air masses appeared to reach a balanced state with the forest environment.
Aki Virkkula, Henrik Grythe, John Backman, Tuukka Petäjä, Maurizio Busetto, Christian Lanconelli, Angelo Lupi, Silvia Becagli, Rita Traversi, Mirko Severi, Vito Vitale, Patrick Sheridan, and Elisabeth Andrews
Atmos. Chem. Phys., 22, 5033–5069,Short summary
Optical properties of surface aerosols at Dome C, Antarctica, in 2007–2013 and their potential source areas are presented. The equivalent black carbon (eBC) mass concentrations were compared with eBC measured at three other Antarctic sites: the South Pole (SPO) and two coastal sites, Neumayer and Syowa. Transport analysis suggests that South American BC emissions are the largest contributor to eBC at Dome C.
Joel Kuula, Hilkka Timonen, Jarkko V. Niemi, Hanna E. Manninen, Topi Rönkkö, Tareq Hussein, Pak Lun Fung, Sasu Tarkoma, Mikko Laakso, Erkka Saukko, Aino Ovaska, Markku Kulmala, Ari Karppinen, Lasse Johansson, and Tuukka Petäjä
Atmos. Chem. Phys., 22, 4801–4808,Short summary
Modern and up-to-date policies and air quality management strategies are instrumental in tackling global air pollution. As the European Union is preparing to revise Ambient Air Quality Directive 2008/50/EC, this paper initiates discussion on selected features of the directive that we believe would benefit from a reassessment. The scientific community has the most recent and deepest understanding of air pollution; thus, its contribution is essential.
Hanna K. Lappalainen, Tuukka Petäjä, Timo Vihma, Jouni Räisänen, Alexander Baklanov, Sergey Chalov, Igor Esau, Ekaterina Ezhova, Matti Leppäranta, Dmitry Pozdnyakov, Jukka Pumpanen, Meinrat O. Andreae, Mikhail Arshinov, Eija Asmi, Jianhui Bai, Igor Bashmachnikov, Boris Belan, Federico Bianchi, Boris Biskaborn, Michael Boy, Jaana Bäck, Bin Cheng, Natalia Chubarova, Jonathan Duplissy, Egor Dyukarev, Konstantinos Eleftheriadis, Martin Forsius, Martin Heimann, Sirkku Juhola, Vladimir Konovalov, Igor Konovalov, Pavel Konstantinov, Kajar Köster, Elena Lapshina, Anna Lintunen, Alexander Mahura, Risto Makkonen, Svetlana Malkhazova, Ivan Mammarella, Stefano Mammola, Stephany Buenrostro Mazon, Outi Meinander, Eugene Mikhailov, Victoria Miles, Stanislav Myslenkov, Dmitry Orlov, Jean-Daniel Paris, Roberta Pirazzini, Olga Popovicheva, Jouni Pulliainen, Kimmo Rautiainen, Torsten Sachs, Vladimir Shevchenko, Andrey Skorokhod, Andreas Stohl, Elli Suhonen, Erik S. Thomson, Marina Tsidilina, Veli-Pekka Tynkkynen, Petteri Uotila, Aki Virkkula, Nadezhda Voropay, Tobias Wolf, Sayaka Yasunaka, Jiahua Zhang, Yubao Qiu, Aijun Ding, Huadong Guo, Valery Bondur, Nikolay Kasimov, Sergej Zilitinkevich, Veli-Matti Kerminen, and Markku Kulmala
Atmos. Chem. Phys., 22, 4413–4469,Short summary
We summarize results during the last 5 years in the northern Eurasian region, especially from Russia, and introduce recent observations of the air quality in the urban environments in China. Although the scientific knowledge in these regions has increased, there are still gaps in our understanding of large-scale climate–Earth surface interactions and feedbacks. This arises from limitations in research infrastructures and integrative data analyses, hindering a comprehensive system analysis.
Lisa J. Beck, Siegfried Schobesberger, Mikko Sipilä, Veli-Matti Kerminen, and Markku Kulmala
Atmos. Meas. Tech., 15, 1957–1965,Short summary
Sulfuric acid is known to be a main compound in atmospheric new particle formation. Yet, its concentration is very low, which leads to challenges in detecting it. In our study, we derive the sulfuric acid concentration from measurements of ambient ions with a mass spectrometer. Our validation shows that the theoretical approach using the bisulfate ion and its clusters with H2SO4 captures the sulfuric acid concentration very well during daytime.
Henry Bowman, Steven Turnock, Susanne E. Bauer, Kostas Tsigaridis, Makoto Deushi, Naga Oshima, Fiona M. O'Connor, Larry Horowitz, Tongwen Wu, Jie Zhang, Dagmar Kubistin, and David D. Parrish
Atmos. Chem. Phys., 22, 3507–3524,Short summary
A full understanding of ozone in the troposphere requires investigation of its temporal variability over all timescales. Model simulations show that the northern midlatitude ozone seasonal cycle shifted with industrial development (1850–2014), with an increasing magnitude and a later summer peak. That shift reached a maximum in the mid-1980s, followed by a reversal toward the preindustrial cycle. The few available observations, beginning in the 1970s, are consistent with the model simulations.
Marjan Marbouti, Sehyun Jang, Silvia Becagli, Gabriel Navarro, Rita Traversi, Kitack Lee, Tuomo Nieminen, Lisa J. Beck, Markku Kulmala, Veli-Matti Kerminen, and Mikko Sipilä
Atmos. Chem. Phys. Discuss.,
Revised manuscript has not been submittedShort summary
This research was done to understand and investigate the roles of Chl-a, PP and sea ice extent in controlling and producing the in-situ measured MSA, SA, HIO3, HOM and aerosol concentrations over the Greenland and Barents Seas. Our results provide strong support to the hypothesis that MSA, SA and small-particle concentrations in the Svalbard area are directly linked to ocean biological activity and sea ice melting during springtime.
Timo Vesala, Kukka-Maaria Kohonen, Linda M. J. Kooijmans, Arnaud P. Praplan, Lenka Foltýnová, Pasi Kolari, Markku Kulmala, Jaana Bäck, David Nelson, Dan Yakir, Mark Zahniser, and Ivan Mammarella
Atmos. Chem. Phys., 22, 2569–2584,Short summary
Carbonyl sulfide (COS) provides new insights into carbon cycle research. We present an easy-to-use flux parameterization and the longest existing time series of forest–atmosphere COS exchange measurements, which allow us to study both seasonal and interannual variability. We observed only uptake of COS by the forest on an annual basis, with 37 % variability between years. Upscaling the boreal COS uptake using a biosphere model indicates a significant missing COS sink at high latitudes.
Mykhailo Savenets, Larysa Pysarenko, Svitlana Krakovska, Alexander Mahura, and Tuukka Petäjä
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
The paper explores spatio-temporal variability of black carbon during a wildfire episode of August 2010 with focus on Ukraine. As a research tool the seamless Enviro-HIRLAM modelling system used for investigating atmospheric transport of aerosol particles emitted by wildfires from remote and local sources. Results of this study improve our understanding of physical/ chemical processes and interactions of aerosols in the atmosphere.
Tuija Jokinen, Katrianne Lehtipalo, Roseline Cutting Thakur, Ilona Ylivinkka, Kimmo Neitola, Nina Sarnela, Totti Laitinen, Markku Kulmala, Tuukka Petäjä, and Mikko Sipilä
Atmos. Chem. Phys., 22, 2237–2254,Short summary
New particle formation is an important source of cloud condensation nuclei; however, long-term measurements of aerosol-forming vapors are close to nonexistent in the Arctic. Here, we report 7 months of CI-APi-TOF measurements of sulfuric acid, iodic acid, methane sulfonic acid and the sum of highly oxygenated organic molecules from the SMEAR I station in the Finnish subarctic. The results help us to understand atmospheric chemical processes and aerosol formation in this rapidly changing area.
Midhun George, Maria Dolores Andrés Hernández, Vladyslav Nenakhov, Yangzhuoran Liu, John Philip Burrows, Birger Bohn, Eric Förster, Florian Obersteiner, Andreas Zahn, Theresa Harlaß, Helmut Ziereis, Hans Schlager, Benjamin Schreiner, Flora Kluge, Katja Bigge, and Klaus Pfeilsticker
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
The applicability photostationary steady-state (PSS) assumptions to estimate the amount of the sum of peroxy radicals (RO2*) during the airborne observations from the known radical chemistry and on-board measurements of RO2* precursors, photolysis frequencies, and other trace gases such as NOx and O3 was investigated. The comparison of the calculated RO2* with the actual measurements provides an insight into the main processes controlling their concentration in the airmasses measured.
Pak Lun Fung, Martha A. Zaidan, Jarkko V. Niemi, Erkka Saukko, Hilkka Timonen, Anu Kousa, Joel Kuula, Topi Rönkkö, Ari Karppinen, Sasu Tarkoma, Markku Kulmala, Tuukka Petäjä, and Tareq Hussein
Atmos. Chem. Phys., 22, 1861–1882,Short summary
We developed an input-adaptive mixed-effects model, which was automatised to select the best combination of input variables, including up to three fixed effect variables and three time indictors as random effect variables. We tested the model to estimate lung-deposited surface area (LDSA), which correlates well with human health. The results show the inclusion of time indicators improved the sensitivity and the accuracy of the model so that it could serve as a network of virtual sensors.
Yanan Zhao, Dennis Booge, Christa A. Marandino, Cathleen Schlundt, Astrid Bracher, Elliot L. Atlas, Jonathan Williams, and Hermann W. Bange
Biogeosciences, 19, 701–714,Short summary
We present here, for the first time, simultaneously measured dimethylsulfide (DMS) seawater concentrations and DMS atmospheric mole fractions from the Peruvian upwelling region during two cruises in December 2012 and October 2015. Our results indicate low oceanic DMS concentrations and atmospheric DMS molar fractions in surface waters and the atmosphere, respectively. In addition, the Peruvian upwelling region was identified as an insignificant source of DMS emissions during both periods.
Peifeng Su, Jorma Joutsensaari, Lubna Dada, Martha Arbayani Zaidan, Tuomo Nieminen, Xinyang Li, Yusheng Wu, Stefano Decesari, Sasu Tarkoma, Tuukka Petäjä, Markku Kulmala, and Petri Pellikka
Atmos. Chem. Phys., 22, 1293–1309,Short summary
We regarded the banana shapes in the surface plots as a special kind of object (similar to cats) and applied an instance segmentation technique to automatically identify the new particle formation (NPF) events (especially the strongest ones), in addition to their growth rates, start times, and end times. The automatic method generalized well on datasets collected in different sites, which is useful for long-term data series analysis and obtaining statistical properties of NPF events.
Arto Heitto, Kari Lehtinen, Tuukka Petäjä, Felipe Lopez-Hilfiker, Joel A. Thornton, Markku Kulmala, and Taina Yli-Juuti
Atmos. Chem. Phys., 22, 155–171,Short summary
For atmospheric aerosol particles to take part in cloud formation, they need to be at least a few tens of nanometers in diameter. By using a particle condensation model, we investigated how two types of chemical reactions, oligomerization and decomposition, of organic molecules inside the particle may affect the growth of secondary aerosol particles to these sizes. We show that the effect is potentially significant, which highlights the importance of increasing understanding of these processes.
Lukas Fischer, Martin Breitenlechner, Eva Canaval, Wiebke Scholz, Marcus Striednig, Martin Graus, Thomas G. Karl, Tuukka Petäjä, Markku Kulmala, and Armin Hansel
Atmos. Meas. Tech., 14, 8019–8039,Short summary
Ecosystems emit biogenic volatile organic compounds (BVOCs), which are then oxidized in the atmosphere, contributing to ozone and secondary aerosol formation. While flux measurements of BVOCs are state of the art, flux measurements of the less volatile oxidation products are difficult to achieve due to inlet losses. Here we present first flux measurements, utilizing a novel PTR3 instrument in combination with a specially designed wall-less inlet we put on top of the Hyytiälä tower in Finland.
Clara M. Nussbaumer, John N. Crowley, Jan Schuladen, Jonathan Williams, Sascha Hafermann, Andreas Reiffs, Raoul Axinte, Hartwig Harder, Cheryl Ernest, Anna Novelli, Katrin Sala, Monica Martinez, Chinmay Mallik, Laura Tomsche, Christian Plass-Dülmer, Birger Bohn, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 21, 18413–18432,Short summary
HCHO is an important atmospheric trace gas influencing the photochemical processes in the Earth’s atmosphere, including the budget of HOx and the abundance of tropospheric O3. This research presents the photochemical calculations of HCHO and O3 based on three field campaigns across Europe. We show that HCHO production via the oxidation of only four volatile organic compound precursors, i.e., CH4, CH3CHO, C5H8 and CH3OH, can balance the observed loss at all sites well.
Ying Zhou, Simo Hakala, Chao Yan, Yang Gao, Xiaohong Yao, Biwu Chu, Tommy Chan, Juha Kangasluoma, Shahzad Gani, Jenni Kontkanen, Pauli Paasonen, Yongchun Liu, Tuukka Petäjä, Markku Kulmala, and Lubna Dada
Atmos. Chem. Phys., 21, 17885–17906,Short summary
We characterized the connection between new particle formation (NPF) events in terms of frequency, intensity and growth at a near-highway location in central Beijing and at a background mountain site 80 km away. Due to the substantial contribution of NPF to the global aerosol budget, identifying the conditions that promote the occurrence of regional NPF events could help understand their contribution on a large scale and would improve their implementation in global models.
Mikko Sipilä, Nina Sarnela, Kimmo Neitola, Totti Laitinen, Deniz Kemppainen, Lisa Beck, Ella-Maria Duplissy, Salla Kuittinen, Tuuli Lehmusjärvi, Janne Lampilahti, Veli-Matti Kerminen, Katrianne Lehtipalo, Pasi P. Aalto, Petri Keronen, Erkki Siivola, Pekka A. Rantala, Douglas R. Worsnop, Markku Kulmala, Tuija Jokinen, and Tuukka Petäjä
Atmos. Chem. Phys., 21, 17559–17576,Short summary
Metallurgical industry in Kola peninsula is a large source of air pollution in the (sub-)Arctic domain. Sulfur dioxide emissions from the ore smelters are transported across large areas. We investigated sulfur dioxide and its transformation to sulfuric acid aerosol particles during winter months in Finnish Lapland, close to Kola industrial areas. We observed intense formation of new aerosol particles despite the low solar radiation intensity, often required for new particle formation elsewhere.
Dirk Dienhart, John N. Crowley, Efstratios Bourtsoukidis, Achim Edtbauer, Philipp G. Eger, Lisa Ernle, Hartwig Harder, Bettina Hottmann, Monica Martinez, Uwe Parchatka, Jean-Daniel Paris, Eva Y. Pfannerstill, Roland Rohloff, Jan Schuladen, Christof Stönner, Ivan Tadic, Sebastian Tauer, Nijing Wang, Jonathan Williams, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 21, 17373–17388,Short summary
We present the first ship-based in situ measurements of formaldehyde (HCHO), hydroxyl radicals (OH) and the OH reactivity around the Arabian Peninsula. Regression analysis of the HCHO production rate and the related OH chemistry revealed the regional HCHO yield αeff, which represents the different chemical regimes encountered. Highest values were found for the Arabian Gulf (also known as the Persian Gulf), which highlights this region as a hotspot of photochemical air pollution.
Clémence Rose, Martine Collaud Coen, Elisabeth Andrews, Yong Lin, Isaline Bossert, Cathrine Lund Myhre, Thomas Tuch, Alfred Wiedensohler, Markus Fiebig, Pasi Aalto, Andrés Alastuey, Elisabeth Alonso-Blanco, Marcos Andrade, Begoña Artíñano, Todor Arsov, Urs Baltensperger, Susanne Bastian, Olaf Bath, Johan Paul Beukes, Benjamin T. Brem, Nicolas Bukowiecki, Juan Andrés Casquero-Vera, Sébastien Conil, Konstantinos Eleftheriadis, Olivier Favez, Harald Flentje, Maria I. Gini, Francisco Javier Gómez-Moreno, Martin Gysel-Beer, Anna Gannet Hallar, Ivo Kalapov, Nikos Kalivitis, Anne Kasper-Giebl, Melita Keywood, Jeong Eun Kim, Sang-Woo Kim, Adam Kristensson, Markku Kulmala, Heikki Lihavainen, Neng-Huei Lin, Hassan Lyamani, Angela Marinoni, Sebastiao Martins Dos Santos, Olga L. Mayol-Bracero, Frank Meinhardt, Maik Merkel, Jean-Marc Metzger, Nikolaos Mihalopoulos, Jakub Ondracek, Marco Pandolfi, Noemi Pérez, Tuukka Petäjä, Jean-Eudes Petit, David Picard, Jean-Marc Pichon, Veronique Pont, Jean-Philippe Putaud, Fabienne Reisen, Karine Sellegri, Sangeeta Sharma, Gerhard Schauer, Patrick Sheridan, James Patrick Sherman, Andreas Schwerin, Ralf Sohmer, Mar Sorribas, Junying Sun, Pierre Tulet, Ville Vakkari, Pieter Gideon van Zyl, Fernando Velarde, Paolo Villani, Stergios Vratolis, Zdenek Wagner, Sheng-Hsiang Wang, Kay Weinhold, Rolf Weller, Margarita Yela, Vladimir Zdimal, and Paolo Laj
Atmos. Chem. Phys., 21, 17185–17223,Short summary
Aerosol particles are a complex component of the atmospheric system the effects of which are among the most uncertain in climate change projections. Using data collected at 62 stations, this study provides the most up-to-date picture of the spatial distribution of particle number concentration and size distribution worldwide, with the aim of contributing to better representation of aerosols and their interactions with clouds in models and, therefore, better evaluation of their impact on climate.
Shahzad Gani, Lukas Kohl, Rima Baalbaki, Federico Bianchi, Taina M. Ruuskanen, Olli-Pekka Siira, Pauli Paasonen, and Hanna Vehkamäki
Geosci. Commun., 4, 507–516,Short summary
In this article, we present authorship guidelines which also include a novel authorship form along with the documentation of the formulation process for a multidisciplinary and interdisciplinary center with more than 250 researchers. Our practical approach promotes fair authorship practices and, by focusing on clear, transparent, and timely communication, helps avoid late-stage authorship conflict.
Zhaofeng Tan, Luisa Hantschke, Martin Kaminski, Ismail-Hakki Acir, Birger Bohn, Changmin Cho, Hans-Peter Dorn, Xin Li, Anna Novelli, Sascha Nehr, Franz Rohrer, Ralf Tillmann, Robert Wegener, Andreas Hofzumahaus, Astrid Kiendler-Scharr, Andreas Wahner, and Hendrik Fuchs
Atmos. Chem. Phys., 21, 16067–16091,Short summary
The photo-oxidation of myrcene, a monoterpene species emitted by plants, was investigated at atmospheric conditions in the outdoor simulation chamber SAPHIR. The chemical structure of myrcene is partly similar to isoprene. Therefore, it can be expected that hydrogen shift reactions could play a role as observed for isoprene. In this work, their potential impact on the regeneration efficiency of hydroxyl radicals is investigated.
Clara M. Nussbaumer, Uwe Parchatka, Ivan Tadic, Birger Bohn, Daniel Marno, Monica Martinez, Roland Rohloff, Hartwig Harder, Flora Kluge, Klaus Pfeilsticker, Florian Obersteiner, Martin Zöger, Raphael Doerich, John N. Crowley, Jos Lelieveld, and Horst Fischer
Atmos. Meas. Tech., 14, 6759–6776,Short summary
NO2 plays a central role in atmospheric photochemical processes and requires accurate measurements. This research presents NO2 data obtained via chemiluminescence using a photolytic converter from airborne studies around Cabo Verde and laboratory investigations. We show the limits and error-proneness of a conventional blue light converter in aircraft measurements affected by humidity and NO levels and suggest the use of an alternative quartz converter for more reliable results.
Krista Luoma, Aki Virkkula, Pasi Aalto, Katrianne Lehtipalo, Tuukka Petäjä, and Markku Kulmala
Atmos. Meas. Tech., 14, 6419–6441,Short summary
The study presents a comparison of three absorption photometers that measured ambient aerosol particles at a boreal forest site. The study aims to better understand problems related to filter-based measurements. Results show how different correction algorithms, which are used to produce the data, affect the derived optical properties of aerosol particles.
Alexandra Gutmann, Nicole Bobrowski, Marcello Liotta, and Thorsten Hoffmann
Atmos. Meas. Tech., 14, 6395–6406,Short summary
Motivated by a special interest in bromine chemistry in volcanic plumes, the study presented here describes a new method for the quantitative collection of gaseous hydrogen bromide in gas diffusion denuders. The hydrogen bromide reacted during sampling with appropriate epoxides applied to the denuder walls. The denuder sampling assembly was successfully deployed in the volcanic plume of Masaya volcano, Nicaragua.
Haoran Li, Ottmar Möhler, Tuukka Petäjä, and Dmitri Moisseev
Atmos. Chem. Phys., 21, 14671–14686,Short summary
In natural clouds, ice-nucleating particles are expected to be rare above –10 °C. In the current paper, we found that the formation of ice columns is frequent in stratiform clouds and is associated with increased precipitation intensity and liquid water path. In single-layer shallow clouds, the production of ice columns was attributed to secondary ice production, despite the rime-splintering process not being expected to take place in such clouds.
Philipp G. Eger, Luc Vereecken, Rolf Sander, Jan Schuladen, Nicolas Sobanski, Horst Fischer, Einar Karu, Jonathan Williams, Ville Vakkari, Tuukka Petäjä, Jos Lelieveld, Andrea Pozzer, and John N. Crowley
Atmos. Chem. Phys., 21, 14333–14349,Short summary
We determine the impact of pyruvic acid photolysis on the formation of acetaldehyde and peroxy radicals during summer and autumn in the Finnish boreal forest using a data-constrained box model. Our results are dependent on the chosen scenario in which the overall quantum yield and the photolysis products are varied. We highlight that pyruvic acid photolysis can be an important contributor to acetaldehyde and peroxy radical formation in remote, forested regions.
Mao Xiao, Christopher R. Hoyle, Lubna Dada, Dominik Stolzenburg, Andreas Kürten, Mingyi Wang, Houssni Lamkaddam, Olga Garmash, Bernhard Mentler, Ugo Molteni, Andrea Baccarini, Mario Simon, Xu-Cheng He, Katrianne Lehtipalo, Lauri R. Ahonen, Rima Baalbaki, Paulus S. Bauer, Lisa Beck, David Bell, Federico Bianchi, Sophia Brilke, Dexian Chen, Randall Chiu, António Dias, Jonathan Duplissy, Henning Finkenzeller, Hamish Gordon, Victoria Hofbauer, Changhyuk Kim, Theodore K. Koenig, Janne Lampilahti, Chuan Ping Lee, Zijun Li, Huajun Mai, Vladimir Makhmutov, Hanna E. Manninen, Ruby Marten, Serge Mathot, Roy L. Mauldin, Wei Nie, Antti Onnela, Eva Partoll, Tuukka Petäjä, Joschka Pfeifer, Veronika Pospisilova, Lauriane L. J. Quéléver, Matti Rissanen, Siegfried Schobesberger, Simone Schuchmann, Yuri Stozhkov, Christian Tauber, Yee Jun Tham, António Tomé, Miguel Vazquez-Pufleau, Andrea C. Wagner, Robert Wagner, Yonghong Wang, Lena Weitz, Daniela Wimmer, Yusheng Wu, Chao Yan, Penglin Ye, Qing Ye, Qiaozhi Zha, Xueqin Zhou, Antonio Amorim, Ken Carslaw, Joachim Curtius, Armin Hansel, Rainer Volkamer, Paul M. Winkler, Richard C. Flagan, Markku Kulmala, Douglas R. Worsnop, Jasper Kirkby, Neil M. Donahue, Urs Baltensperger, Imad El Haddad, and Josef Dommen
Atmos. Chem. Phys., 21, 14275–14291,Short summary
Experiments at CLOUD show that in polluted environments new particle formation (NPF) is largely driven by the formation of sulfuric acid–base clusters, stabilized by amines, high ammonia concentrations or lower temperatures. While oxidation products of aromatics can nucleate, they play a minor role in urban NPF. Our experiments span 4 orders of magnitude variation of observed NPF rates in ambient conditions. We provide a framework based on NPF and growth rates to interpret ambient observations.
Alex Resovsky, Michel Ramonet, Leonard Rivier, Jerome Tarniewicz, Philippe Ciais, Martin Steinbacher, Ivan Mammarella, Meelis Mölder, Michal Heliasz, Dagmar Kubistin, Matthias Lindauer, Jennifer Müller-Williams, Sebastien Conil, and Richard Engelen
Atmos. Meas. Tech., 14, 6119–6135,Short summary
We present a technical description of a statistical methodology for extracting synoptic- and seasonal-length anomalies from greenhouse gas time series. The definition of what represents an anomalous signal is somewhat subjective, which we touch on throughout the paper. We show, however, that the method performs reasonably well in extracting portions of time series influenced by significant North Atlantic Oscillation weather episodes and continent-wide terrestrial biospheric aberrations.
Yongchun Liu, Zemin Feng, Feixue Zheng, Xiaolei Bao, Pengfei Liu, Yanli Ge, Yan Zhao, Tao Jiang, Yunwen Liao, Yusheng Zhang, Xiaolong Fan, Chao Yan, Biwu Chu, Yonghong Wang, Wei Du, Jing Cai, Federico Bianchi, Tuukka Petäjä, Yujing Mu, Hong He, and Markku Kulmala
Atmos. Chem. Phys., 21, 13269–13286,Short summary
The mechanisms and kinetics of particulate sulfate formation in the atmosphere are still open questions although they have been extensively discussed. We found that uptake of SO2 is the rate-determining step for the conversion of SO2 to particulate sulfate. NH4NO3 plays an important role in AWC, the phase state of aerosol particles, and subsequently the uptake kinetics of SO2 under high-RH conditions. This work is a good example of the feedback between aerosol physics and aerosol chemistry.
Helmi Uusitalo, Jenni Kontkanen, Ilona Ylivinkka, Ekaterina Ezhova, Anastasiia Demakova, Mikhail Arshinov, Boris Denisovich Belan, Denis Davydov, Nan Ma, Tuukka Petäjä, Alfred Wiedensohler, Markku Kulmala, and Tuomo Nieminen
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
Characteristics of formation of atmospheric aerosol at four boreal forest sites in Finland and Russian Siberia was analyzed. Our results provide information on the governing processes of atmospheric aerosol formation in the boreal forest area, which a substantial part of the continental biosphere. Aerosol formation was occurring less frequently at Siberian than in Finnish sites, which was affected by the lower particle growth rates and higher loss rates in Siberia.
Janne Lampilahti, Hanna E. Manninen, Tuomo Nieminen, Sander Mirme, Mikael Ehn, Iida Pullinen, Katri Leino, Siegfried Schobesberger, Juha Kangasluoma, Jenni Kontkanen, Emma Järvinen, Riikka Väänänen, Taina Yli-Juuti, Radovan Krejci, Katrianne Lehtipalo, Janne Levula, Aadu Mirme, Stefano Decesari, Ralf Tillmann, Douglas R. Worsnop, Franz Rohrer, Astrid Kiendler-Scharr, Tuukka Petäjä, Veli-Matti Kerminen, Thomas F. Mentel, and Markku Kulmala
Atmos. Chem. Phys., 21, 12649–12663,Short summary
We studied aerosol particle formation and growth in different parts of the planetary boundary layer at two different locations (Po Valley, Italy, and Hyytiälä, Finland). The observations consist of airborne measurements on board an instrumented Zeppelin and a small airplane combined with comprehensive ground-based measurements.
Luisa Hantschke, Anna Novelli, Birger Bohn, Changmin Cho, David Reimer, Franz Rohrer, Ralf Tillmann, Marvin Glowania, Andreas Hofzumahaus, Astrid Kiendler-Scharr, Andreas Wahner, and Hendrik Fuchs
Atmos. Chem. Phys., 21, 12665–12685,Short summary
The reactions of Δ3-carene with ozone and the hydroxyl radical (OH) and the photolysis and OH reaction of caronaldehyde were investigated in the simulation chamber SAPHIR. Reaction rate constants of these reactions were determined. Caronaldehyde yields of the ozonolysis and OH reaction were determined. The organic nitrate yield of the reaction of Δ3-carene and caronaldehyde-derived peroxy radicals with NO was determined. The ROx budget (ROx = OH+HO2+RO2) was also investigated.
James Weber, Scott Archer-Nicholls, Nathan Luke Abraham, Youngsub M. Shin, Thomas J. Bannan, Carl J. Percival, Asan Bacak, Paulo Artaxo, Michael Jenkin, M. Anwar H. Khan, Dudley E. Shallcross, Rebecca H. Schwantes, Jonathan Williams, and Alex T. Archibald
Geosci. Model Dev., 14, 5239–5268,Short summary
The new mechanism CRI-Strat 2 features state-of-the-art isoprene chemistry not previously available in UKCA and improves UKCA's ability to reproduce observed concentrations of isoprene, monoterpenes, and OH in tropical regions. The enhanced ability to model isoprene, the most widely emitted non-methane volatile organic compound (VOC), will allow understanding of how isoprene and other biogenic VOCs affect atmospheric composition and, through biosphere–atmosphere feedbacks, climate change.
Jean-Daniel Paris, Aurélie Riandet, Efstratios Bourtsoukidis, Marc Delmotte, Antoine Berchet, Jonathan Williams, Lisa Ernle, Ivan Tadic, Hartwig Harder, and Jos Lelieveld
Atmos. Chem. Phys., 21, 12443–12462,Short summary
We measured atmospheric methane and CO2 by ship in the Middle East. We probe the origin of methane with a combination of light alkane measurements and modeling. We find strong influence from nearby oil and gas production over the Arabian Gulf. Comparing our data to inventories indicates that inventories overestimate sources from the upstream gas industry but underestimate emissions from oil extraction and processing. The Red Sea was under a complex mixture of sources due to human activity.
Zhuohui Lin, Yonghong Wang, Feixue Zheng, Ying Zhou, Yishuo Guo, Zemin Feng, Chang Li, Yusheng Zhang, Simo Hakala, Tommy Chan, Chao Yan, Kaspar R. Daellenbach, Biwu Chu, Lubna Dada, Juha Kangasluoma, Lei Yao, Xiaolong Fan, Wei Du, Jing Cai, Runlong Cai, Tom V. Kokkonen, Putian Zhou, Lili Wang, Tuukka Petäjä, Federico Bianchi, Veli-Matti Kerminen, Yongchun Liu, and Markku Kulmala
Atmos. Chem. Phys., 21, 12173–12187,Short summary
We find that ammonium nitrate and aerosol water content contributed most during low mixing layer height conditions; this may further trigger enhanced formation of sulfate and organic aerosol via heterogeneous reactions. The results of this study contribute towards a more detailed understanding of the aerosol–chemistry–radiation–boundary layer feedback that is likely to be responsible for explosive aerosol mass growth events in urban Beijing.
Pak Lun Fung, Martha Arbayani Zaidan, Ola Surakhi, Sasu Tarkoma, Tuukka Petäjä, and Tareq Hussein
Atmos. Meas. Tech., 14, 5535–5554,Short summary
Aerosol size distribution measurements rely on a variety of techniques to classify the aerosol size and measure the size distribution. However, due to the instrumental insufficiency and inversion limitations, the raw dataset contains missing gaps or negative values, which hinder further analysis. With a merged particle size distribution in Jordan, this paper suggests a neural network method to estimate number concentrations at a particular size bin by the number concentration at other size bins.
Dimitrios Bousiotis, Francis D. Pope, David C. S. Beddows, Manuel Dall'Osto, Andreas Massling, Jakob Klenø Nøjgaard, Claus Nordstrøm, Jarkko V. Niemi, Harri Portin, Tuukka Petäjä, Noemi Perez, Andrés Alastuey, Xavier Querol, Giorgos Kouvarakis, Nikos Mihalopoulos, Stergios Vratolis, Konstantinos Eleftheriadis, Alfred Wiedensohler, Kay Weinhold, Maik Merkel, Thomas Tuch, and Roy M. Harrison
Atmos. Chem. Phys., 21, 11905–11925,Short summary
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.
Xiaolong Fan, Jing Cai, Chao Yan, Jian Zhao, Yishuo Guo, Chang Li, Kaspar R. Dällenbach, Feixue Zheng, Zhuohui Lin, Biwu Chu, Yonghong Wang, Lubna Dada, Qiaozhi Zha, Wei Du, Jenni Kontkanen, Theo Kurtén, Siddhart Iyer, Joni T. Kujansuu, Tuukka Petäjä, Douglas R. Worsnop, Veli-Matti Kerminen, Yongchun Liu, Federico Bianchi, Yee Jun Tham, Lei Yao, and Markku Kulmala
Atmos. Chem. Phys., 21, 11437–11452,Short summary
We observed significant concentrations of gaseous HBr and HCl throughout the winter and springtime in urban Beijing, China. Our results indicate that gaseous HCl and HBr are most likely originated from anthropogenic emissions such as burning activities, and the gas–aerosol partitioning may play a crucial role in contributing to the gaseous HCl and HBr. These observations suggest that there is an important recycling pathway of halogen species in inland megacities.
Rongrong Wu, Luc Vereecken, Epameinondas Tsiligiannis, Sungah Kang, Sascha R. Albrecht, Luisa Hantschke, Defeng Zhao, Anna Novelli, Hendrik Fuchs, Ralf Tillmann, Thorsten Hohaus, Philip T. M. Carlsson, Justin Shenolikar, François Bernard, John N. Crowley, Juliane L. Fry, Bellamy Brownwood, Joel A. Thornton, Steven S. Brown, Astrid Kiendler-Scharr, Andreas Wahner, Mattias Hallquist, and Thomas F. Mentel
Atmos. Chem. Phys., 21, 10799–10824,Short summary
Isoprene is the biogenic volatile organic compound with the largest emissions rates. The nighttime reaction of isoprene with the NO3 radical has a large potential to contribute to SOA. We classified isoprene nitrates into generations and proposed formation pathways. Considering the potential functionalization of the isoprene nitrates we propose that mainly isoprene dimers contribute to SOA formation from the isoprene NO3 reactions with at least a 5 % mass yield.
Haijie Tong, Fobang Liu, Alexander Filippi, Jake Wilson, Andrea M. Arangio, Yun Zhang, Siyao Yue, Steven Lelieveld, Fangxia Shen, Helmi-Marja K. Keskinen, Jing Li, Haoxuan Chen, Ting Zhang, Thorsten Hoffmann, Pingqing Fu, William H. Brune, Tuukka Petäjä, Markku Kulmala, Maosheng Yao, Thomas Berkemeier, Manabu Shiraiwa, and Ulrich Pöschl
Atmos. Chem. Phys., 21, 10439–10455,Short summary
We measured radical yields of aqueous PM2.5 extracts and found lower yields at higher concentrations of PM2.5. Abundances of water-soluble transition metals and aromatics in PM2.5 were positively correlated with the relative fraction of •OH but negatively correlated with the relative fraction of C-centered radicals among detected radicals. Composition-dependent reactive species yields may explain differences in the reactivity and health effects of PM2.5 in clean versus polluted air.
Liine Heikkinen, Mikko Äijälä, Kaspar R. Daellenbach, Gang Chen, Olga Garmash, Diego Aliaga, Frans Graeffe, Meri Räty, Krista Luoma, Pasi Aalto, Markku Kulmala, Tuukka Petäjä, Douglas Worsnop, and Mikael Ehn
Atmos. Chem. Phys., 21, 10081–10109,Short summary
In many locations worldwide aerosol particles have been shown to be made up of organic aerosol (OA). The boreal forest is a region where aerosol particles possess a high OA mass fraction. Here, we studied OA composition using the longest time series of OA composition ever obtained from a boreal environment. For this purpose, we tested a new analysis framework and discovered that most of the OA was highly oxidized, with strong seasonal behaviour reflecting different sources in summer and winter.
Magdalena Okuljar, Heino Kuuluvainen, Jenni Kontkanen, Olga Garmash, Miska Olin, Jarkko V. Niemi, Hilkka Timonen, Juha Kangasluoma, Yee Jun Tham, Rima Baalbaki, Mikko Sipilä, Laura Salo, Henna Lintusaari, Harri Portin, Kimmo Teinilä, Minna Aurela, Miikka Dal Maso, Topi Rönkkö, Tuukka Petäjä, and Pauli Paasonen
Atmos. Chem. Phys., 21, 9931–9953,Short summary
To estimate the relative contribution of different sources to the particle population in an urban environment, we conducted simultaneous measurements at a street canyon and an urban background station in Helsinki. We investigated the contribution of traffic and new particle formation to particles with a diameter between 1 and 800 nm. We found that during spring traffic does not dominate the particles smaller than 3 nm at either of the stations.
Rima Baalbaki, Michael Pikridas, Tuija Jokinen, Tiia Laurila, Lubna Dada, Spyros Bezantakos, Lauri Ahonen, Kimmo Neitola, Anne Maisser, Elie Bimenyimana, Aliki Christodoulou, Florin Unga, Chrysanthos Savvides, Katrianne Lehtipalo, Juha Kangasluoma, George Biskos, Tuukka Petäjä, Veli-Matti Kerminen, Jean Sciare, and Markku Kulmala
Atmos. Chem. Phys., 21, 9223–9251,Short summary
This study investigates new particle formation (NPF) in the less represented region of the Mediterranean basin using 1-year measurements of aerosol particles down to ~ 1 nm in diameter. We report a high frequency of NPF and give examples of interesting NPF features. We quantify the strength of NPF events by calculating formation rates and growth rates. We further unveil the atmospheric conditions and variables considered important for the intra-monthly and inter-monthly occurrence of NPF.
Kai Wang, Ru-Jin Huang, Martin Brüggemann, Yun Zhang, Lu Yang, Haiyan Ni, Jie Guo, Meng Wang, Jiajun Han, Merete Bilde, Marianne Glasius, and Thorsten Hoffmann
Atmos. Chem. Phys., 21, 9089–9104,Short summary
Here we present the detailed molecular composition of the organic aerosol collected in three eastern Chinese cities from north to south, Changchun, Shanghai and Guangzhou, by applying LC–Orbitrap analysis. Accordingly, the aromaticity degree of chemical compounds decreases from north to south, while the oxidation degree increases from north to south, which can be explained by the different anthropogenic emissions and photochemical oxidation processes.
Jose Ruiz-Jimenez, Magdalena Okuljar, Outi-Maaria Sietiö, Giorgia Demaria, Thanaporn Liangsupree, Elisa Zagatti, Juho Aalto, Kari Hartonen, Jussi Heinonsalo, Jaana Bäck, Tuukka Petäjä, and Marja-Liisa Riekkola
Atmos. Chem. Phys., 21, 8775–8790,Short summary
Altogether, 84 size-segregated aerosol samples from four particle size fractions were collected at the Station for Measuring Forest Ecosystem-Atmosphere Relations, Hyytiälä, Finland, in autumn 2017 for the clarification of the complex interrelationships between airborne and particulate chemical traces, amino acids and saccharides, gene copy numbers (16S and 18S for bacteria and fungi, respectively), gas-phase chemistry, and the particle size distribution.
Bo Galle, Santiago Arellano, Nicole Bobrowski, Vladimir Conde, Tobias P. Fischer, Gustav Gerdes, Alexandra Gutmann, Thorsten Hoffmann, Ima Itikarai, Tomas Krejci, Emma J. Liu, Kila Mulina, Scott Nowicki, Tom Richardson, Julian Rüdiger, Kieran Wood, and Jiazhi Xu
Atmos. Meas. Tech., 14, 4255–4277,Short summary
Measurements of volcanic gases are important for geophysical research, risk assessment and environmental impact studies. Some gases, like SO2 and BrO, may be studied from the ground at a safe distance using remote sensing techniques. Many other gases require in situ access to the gas plume. Here, a drone may be an attractive alternative. This paper describes a drone specially adapted for volcanic gas studies and demonstrates its use in a field campaign at Manam volcano in Papua New Guinea.
Mingyi Wang, Xu-Cheng He, Henning Finkenzeller, Siddharth Iyer, Dexian Chen, Jiali Shen, Mario Simon, Victoria Hofbauer, Jasper Kirkby, Joachim Curtius, Norbert Maier, Theo Kurtén, Douglas R. Worsnop, Markku Kulmala, Matti Rissanen, Rainer Volkamer, Yee Jun Tham, Neil M. Donahue, and Mikko Sipilä
Atmos. Meas. Tech., 14, 4187–4202,Short summary
Atmospheric iodine species are often short-lived with low abundance and have thus been challenging to measure. We show that the bromide chemical ionization mass spectrometry, compatible with both the atmospheric pressure and reduced pressure interfaces, can simultaneously detect various gas-phase iodine species. Combining calibration experiments and quantum chemical calculations, we quantify detection sensitivities to HOI, HIO3, I2, and H2SO4, giving detection limits down to < 106 molec. cm-3.
Markku Kulmala, Tom V. Kokkonen, Juha Pekkanen, Sami Paatero, Tuukka Petäjä, Veli-Matti Kerminen, and Aijun Ding
Atmos. Chem. Phys., 21, 8313–8322,Short summary
The eastern part of China as a whole is practically a gigacity with 650 million inhabitants. The gigacity, with its emissions, processes in the pollution cocktail and numerous feedbacks and interactions, has a crucial and big impact on regional air quality and on global climate. A large-scale research and innovation program is needed to meet the interlinked grand challenges in this gigacity and to serve as a platform for finding pathways for sustainable development of the globe.
Ivan Tadic, Clara M. Nussbaumer, Birger Bohn, Hartwig Harder, Daniel Marno, Monica Martinez, Florian Obersteiner, Uwe Parchatka, Andrea Pozzer, Roland Rohloff, Martin Zöger, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 21, 8195–8211,Short summary
Although mechanisms of tropospheric ozone (O3) formation are well understood, studies reporting on ozone formation derived from field measurements are challenging and remain sparse in number. We use airborne measurements to quantify nitric oxide (NO) and O3 distributions in the upper troposphere over the Atlantic Ocean and western Africa and compare our measurements to model simulations. Our results show that NO and ozone formation are greatest over the tropical areas of western Africa.
Heidi Hellén, Arnaud P. Praplan, Toni Tykkä, Aku Helin, Simon Schallhart, Piia P. Schiestl-Aalto, Jaana Bäck, and Hannele Hakola
Atmos. Chem. Phys., 21, 8045–8066,Short summary
Even though terpene emissions of boreal needle trees have been studied quite intensively, there is less knowledge of the emissions of broadleaved deciduous trees and emissions of larger terpenes and oxygenated volatile organic compounds. Here we studied downy birch (Betula pubescens) emissions, and especially sesquiterpene and oxygenated sesquiterpene emissions were found to be high. These emissions may have significant effects on secondary organic aerosol formation in boreal areas.
Janne Lampilahti, Katri Leino, Antti Manninen, Pyry Poutanen, Anna Franck, Maija Peltola, Paula Hietala, Lisa Beck, Lubna Dada, Lauriane Quéléver, Ronja Öhrnberg, Ying Zhou, Madeleine Ekblom, Ville Vakkari, Sergej Zilitinkevich, Veli-Matti Kerminen, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 21, 7901–7915,Short summary
Using airborne measurements we observed increased number concentrations of sub-25 nm particles in the upper residual layer. These particles may be entrained into the well-mixed boundary layer and observed at the surface. We attribute our observations to new particle formation in the topmost part of the residual layer.
Clara M. Nussbaumer, Ivan Tadic, Dirk Dienhart, Nijing Wang, Achim Edtbauer, Lisa Ernle, Jonathan Williams, Florian Obersteiner, Isidoro Gutiérrez-Álvarez, Hartwig Harder, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 21, 7933–7945,Short summary
Lightning over continental and coastal areas is frequent and accompanied by deep convection, while lightning over marine areas and particularly in tropical cyclones is rare. This research presents in situ observations of the tropical storm Florence 2018 near Cabo Verde. We show the absence of lightning in the tropical storm despite the occurrence of deep convective processes by atmospheric trace gas measurements of O3, NO, CO, H2O2, DMS and CH2I.
Nils Friedrich, Philipp Eger, Justin Shenolikar, Nicolas Sobanski, Jan Schuladen, Dirk Dienhart, Bettina Hottmann, Ivan Tadic, Horst Fischer, Monica Martinez, Roland Rohloff, Sebastian Tauer, Hartwig Harder, Eva Y. Pfannerstill, Nijing Wang, Jonathan Williams, James Brooks, Frank Drewnick, Hang Su, Guo Li, Yafang Cheng, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 21, 7473–7498,Short summary
This paper uses NOx and NOz measurements from the 2017 AQABA ship campaign in the Mediterranean Sea and around the Arabian Peninsula to examine the influence e.g. of emissions from shipping and oil and gas production. Night-time losses of NOx dominated in the Arabian Gulf and in the Red Sea, whereas daytime losses were more important in the Mediterranean Sea. Nitric acid and organic nitrates were the most prevalent components of NOz.
Robbie Ramsay, Chiara F. Di Marco, Mathew R. Heal, Matthias Sörgel, Paulo Artaxo, Meinrat O. Andreae, and Eiko Nemitz
Biogeosciences, 18, 2809–2825,Short summary
The exchange of the gas ammonia between the atmosphere and the surface is an important biogeochemical process, but little is known of this exchange for certain ecosystems, such as the Amazon rainforest. This study took measurements of ammonia exchange over an Amazon rainforest site and subsequently modelled the observed deposition and emission patterns. We observed emissions of ammonia from the rainforest, which can be simulated accurately by using a canopy resistance modelling approach.
Eva Y. Pfannerstill, Nina G. Reijrink, Achim Edtbauer, Akima Ringsdorf, Nora Zannoni, Alessandro Araújo, Florian Ditas, Bruna A. Holanda, Marta O. Sá, Anywhere Tsokankunku, David Walter, Stefan Wolff, Jošt V. Lavrič, Christopher Pöhlker, Matthias Sörgel, and Jonathan Williams
Atmos. Chem. Phys., 21, 6231–6256,Short summary
Tropical forests are globally significant for atmospheric chemistry. However, the mixture of reactive organic gases emitted by these ecosystems is poorly understood. By comprehensive observations at an Amazon forest site, we show that oxygenated species were previously underestimated in their contribution to the tropical-forest reactant mix. Our results show rain and temperature effects and have implications for models and the understanding of ozone and particle formation above tropical forests.
Inken Heidke, Adam Hartland, Denis Scholz, Andrew Pearson, John Hellstrom, Sebastian F. M. Breitenbach, and Thorsten Hoffmann
Biogeosciences, 18, 2289–2300,Short summary
We analyzed lignin oxidation products (LOPs) in leaf litter and different soil horizons as well as dripwater and flowstone samples from four different cave sites from different vegetation zones in New Zealand using liquid chromatography coupled to mass spectrometry. We test whether the original source-dependent LOP signal of the overlying vegetation is preserved and can be recovered from flowstone samples and investigate how the signal is altered by the transport from the soil to the cave.
Dana L. McGuffin, Yuanlong Huang, Richard C. Flagan, Tuukka Petäjä, B. Erik Ydstie, and Peter J. Adams
Geosci. Model Dev., 14, 1821–1839,Short summary
Atmospheric particle formation, emissions, and growth process rates are significant sources of uncertainty in predicting climate change. We aim to reduce that uncertainty by using measurements from several ground-based sites across Europe. We developed an estimation technique to adapt the governing process rates so model–measurement bias decays. The estimation framework developed has potential to improve model predictions while providing insight into the underlying atmospheric particle physics.
Alexander Zaytsev, Martin Breitenlechner, Anna Novelli, Hendrik Fuchs, Daniel A. Knopf, Jesse H. Kroll, and Frank N. Keutsch
Atmos. Meas. Tech., 14, 2501–2513,Short summary
We have developed an online method for speciated measurements of organic peroxy radicals and stabilized Criegee intermediates using chemical derivatization combined with chemical ionization mass spectrometry. Chemical derivatization prevents secondary radical reactions and eliminates potential interferences. Comparison between our measurements and results from numeric modeling shows that the method can be used for the quantification of a wide range of atmospheric radicals and intermediates.
Thomas Thorp, Stephen R. Arnold, Richard J. Pope, Dominick V. Spracklen, Luke Conibear, Christoph Knote, Mikhail Arshinov, Boris Belan, Eija Asmi, Tuomas Laurila, Andrei I. Skorokhod, Tuomo Nieminen, and Tuukka Petäjä
Atmos. Chem. Phys., 21, 4677–4697,Short summary
We compare modelled near-surface pollutants with surface and satellite observations to better understand the controls on the regional concentrations of pollution in western Siberia for late spring and summer in 2011. We find two commonly used emission inventories underestimate human emissions when compared to observations. Transport emissions are the main source of pollutants within the region during this period, whilst fire emissions peak during June and are only significant south of 60° N.
Wenjie Wang, Jipeng Qi, Jun Zhou, Bin Yuan, Yuwen Peng, Sihang Wang, Suxia Yang, Jonathan Williams, Vinayak Sinha, and Min Shao
Atmos. Meas. Tech., 14, 2285–2298,Short summary
We designed a new reactor for measurements of OH reactivity (i.e., OH radical loss frequency) based on the comparative reactivity method under high-NOx conditions, such as in cities. We performed a series of laboratory tests to evaluate the new reactor. The new reactor was used in the field and performed well in measuring OH reactivity in air influenced by upwind cities.
Julia Schneider, Kristina Höhler, Paavo Heikkilä, Jorma Keskinen, Barbara Bertozzi, Pia Bogert, Tobias Schorr, Nsikanabasi Silas Umo, Franziska Vogel, Zoé Brasseur, Yusheng Wu, Simo Hakala, Jonathan Duplissy, Dmitri Moisseev, Markku Kulmala, Michael P. Adams, Benjamin J. Murray, Kimmo Korhonen, Liqing Hao, Erik S. Thomson, Dimitri Castarède, Thomas Leisner, Tuukka Petäjä, and Ottmar Möhler
Atmos. Chem. Phys., 21, 3899–3918,Short summary
By triggering the formation of ice crystals, ice-nucleating particles (INP) strongly influence cloud formation. Continuous, long-term measurements are needed to characterize the atmospheric INP variability. Here, a first long-term time series of INP spectra measured in the boreal forest for more than 1 year is presented, showing a clear seasonal cycle. It is shown that the seasonal dependency of INP concentrations and prevalent INP types is driven by the abundance of biogenic aerosol.
Wei Yuan, Ru-Jin Huang, Lu Yang, Ting Wang, Jing Duan, Jie Guo, Haiyan Ni, Yang Chen, Qi Chen, Yongjie Li, Ulrike Dusek, Colin O'Dowd, and Thorsten Hoffmann
Atmos. Chem. Phys., 21, 3685–3697,Short summary
We characterized the seasonal variations in nitrated aromatic compounds (NACs) in composition, sources, and their light absorption contribution to brown carbon (BrC) aerosol in Xi'an, Northwest China. Our results show that secondary formation and vehicular emission were dominant sources in summer (~80 %), and biomass burning and coal combustion were major sources in winter (~75 %), and they indicate that the composition and sources of NACs have a profound impact on the light absorption of BrC
Denis Leppla, Nora Zannoni, Leslie Kremper, Jonathan Williams, Christopher Pöhlker, Marta Sá, Maria Christina Solci, and Thorsten Hoffmann
Atmos. Chem. Phys. Discuss.,
Revised manuscript under review for ACP
Changmin Cho, Andreas Hofzumahaus, Hendrik Fuchs, Hans-Peter Dorn, Marvin Glowania, Frank Holland, Franz Rohrer, Vaishali Vardhan, Astrid Kiendler-Scharr, Andreas Wahner, and Anna Novelli
Atmos. Meas. Tech., 14, 1851–1877,Short summary
This study describes the implementation and characterization of the chemical modulation reactor (CMR) used in the laser-induced fluorescence instrument of the Forschungszentrum Jülich. The CMR allows for interference-free OH radical measurement in ambient air. During a field campaign in a rural environment, the observed interference was mostly below the detection limit of the instrument and fully explained by the known ozone interference.
Julian Rüdiger, Alexandra Gutmann, Nicole Bobrowski, Marcello Liotta, J. Maarten de Moor, Rolf Sander, Florian Dinger, Jan-Lukas Tirpitz, Martha Ibarra, Armando Saballos, María Martínez, Elvis Mendoza, Arnoldo Ferrufino, John Stix, Juan Valdés, Jonathan M. Castro, and Thorsten Hoffmann
Atmos. Chem. Phys., 21, 3371–3393,Short summary
We present an innovative approach to study halogen chemistry in the plume of Masaya volcano in Nicaragua. An unique data set was collected using multiple techniques, including drones. These data enabled us to determine the fraction of activation of the respective halogens at various plume ages, where in-mixing of ambient air causes chemical reactions. An atmospheric chemistry box model was employed to further examine the field results and help our understanding of volcanic plume chemistry.
Einar Karu, Mengze Li, Lisa Ernle, Carl A. M. Brenninkmeijer, Jos Lelieveld, and Jonathan Williams
Atmos. Meas. Tech., 14, 1817–1831,Short summary
A gas measurement device was developed to measure trace gases (ppt level) in the air based on an atomic emission detector. It combines a cryogenic pre-concentrator (CryoTrap), a gas chromatograph (GC), and a new high-resolution atomic emission detector (AED). The CryoTrap–GC–AED instrumental setup, limits of detection, and elemental performance are presented and discussed. Two measurement case studies are reported: one in a Finnish boreal forest and the other based on an aircraft campaign.
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,Short summary
New particle formation events from 16 sites over Europe have been studied, and the influence of meteorological and atmospheric composition variables has been investigated. Some variables, like solar radiation intensity and temperature, have a positive effect on the occurrence of these events, while others have a negative effect, affecting different aspects such as the rate at which particles are formed or grow. This effect varies depending on the site type and magnitude of these variables.
Imre Salma, Wanda Thén, Pasi Aalto, Veli-Matti Kerminen, Anikó Kern, Zoltán Barcza, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 21, 2861–2880,Short summary
The distribution of the monthly mean nucleation frequency possessed a characteristic pattern. Its shape was compared to those of environmental variables, including vegetation-derived properties. The spring maximum in the occurrence frequency often overlapped with the positive T anomaly. The link between the heat stress and the occurrence minimum in summer could not be proven, whereas an association between the occurrence frequency and vegetation growth dynamics was clearly identified in spring.
Runlong Cai, Chao Yan, Dongsen Yang, Rujing Yin, Yiqun Lu, Chenjuan Deng, Yueyun Fu, Jiaxin Ruan, Xiaoxiao Li, Jenni Kontkanen, Qiang Zhang, Juha Kangasluoma, Yan Ma, Jiming Hao, Douglas R. Worsnop, Federico Bianchi, Pauli Paasonen, Veli-Matti Kerminen, Yongchun Liu, Lin Wang, Jun Zheng, Markku Kulmala, and Jingkun Jiang
Atmos. Chem. Phys., 21, 2457–2468,Short summary
Based on long-term measurements, we discovered that the collision of H2SO4–amine clusters is the governing mechanism that initializes fast new particle formation in the polluted atmospheric environment of urban Beijing. The mechanism and the governing factors for H2SO4–amine nucleation in the polluted atmosphere are quantitatively investigated in this study.
Krista Luoma, Jarkko V. Niemi, Minna Aurela, Pak Lun Fung, Aku Helin, Tareq Hussein, Leena Kangas, Anu Kousa, Topi Rönkkö, Hilkka Timonen, Aki Virkkula, and Tuukka Petäjä
Atmos. Chem. Phys., 21, 1173–1189,Short summary
This study combined black carbon measurements from 15 Finnish sites that represented different environments (traffic, detached housing area, urban background, and regional background). The seasonal and diurnal variations in the black carbon concentration were associated with local emissions from traffic and residential wood burning. The study observed decreasing trends in the black carbon concentration and associated them with decreases in traffic emissions.
Juha Sulo, Nina Sarnela, Jenni Kontkanen, Lauri Ahonen, Pauli Paasonen, Tiia Laurila, Tuija Jokinen, Juha Kangasluoma, Heikki Junninen, Mikko Sipilä, Tuukka Petäjä, Markku Kulmala, and Katrianne Lehtipalo
Atmos. Chem. Phys., 21, 695–715,Short summary
In this study, we analyzed over 5 years of sub-3 nm particle concentrations and their precursor vapors, identifying atmoshperic vapors important to the formation of these particles in the boreal forest. We also observed seasonal differences in both particle and precursor vapor concentrations and the formation pathways of these particles. Our results confirm the importance of organic vapors in atmospheric aerosol formation and highlight key seasonal differences that require further study.
Oleg Sizov, Ekaterina Ezhova, Petr Tsymbarovich, Andrey Soromotin, Nikolay Prihod'ko, Tuukka Petäjä, Sergej Zilitinkevich, Markku Kulmala, Jaana Bäck, and Kajar Köster
Biogeosciences, 18, 207–228,Short summary
In changing climate, tundra is expected to turn into shrubs and trees, diminishing reindeer pasture and increasing risks of tick-borne diseases. However, this transition may require a disturbance. Fires in Siberia are increasingly widespread. We studied wildfire dynamics and tundra–forest transition over 60 years in northwest Siberia near the Arctic Circle. Based on satellite data analysis, we found that transition occurs in 40 %–85 % of burned tundra compared to 5 %–15 % in non-disturbed areas.
Guilherme F. Camarinha-Neto, Julia C. P. Cohen, Cléo Q. Dias-Júnior, Matthias Sörgel, José Henrique Cattanio, Alessandro Araújo, Stefan Wolff, Paulo A. F. Kuhn, Rodrigo A. F. Souza, Luciana V. Rizzo, and Paulo Artaxo
Atmos. Chem. Phys., 21, 339–356,Short summary
It was observed that friagem phenomena (incursion of cold waves from the high latitudes of the Southern Hemisphere to the Amazon region), very common in the dry season of the Amazon region, produced significant changes in microclimate and atmospheric chemistry. Moreover, the effects of the friagem change the surface O3 and CO2 mixing ratios and therefore interfere deeply in the microclimatic conditions and the chemical composition of the atmosphere above the rainforest.
Maximilian Reuter, Heinrich Bovensmann, Michael Buchwitz, Jakob Borchardt, Sven Krautwurst, Konstantin Gerilowski, Matthias Lindauer, Dagmar Kubistin, and John P. Burrows
Atmos. Meas. Tech., 14, 153–172,Short summary
CO2 measurements from a small unmanned aircraft system (sUAS) can provide a cost-effective way to complement and validate satellite-based measurements of anthropogenic CO2 emissions. We introduce an sUAS which is capable of determining atmospheric CO2 mass fluxes from its own sensor data. We show results of validation flights at the ICOS atmospheric station in Steinkimmen and from demonstration flights downwind a CO2-emitting natural gas processing facility.
Camille Yver-Kwok, Carole Philippon, Peter Bergamaschi, Tobias Biermann, Francescopiero Calzolari, Huilin Chen, Sebastien Conil, Paolo Cristofanelli, Marc Delmotte, Juha Hatakka, Michal Heliasz, Ove Hermansen, Kateřina Komínková, Dagmar Kubistin, Nicolas Kumps, Olivier Laurent, Tuomas Laurila, Irene Lehner, Janne Levula, Matthias Lindauer, Morgan Lopez, Ivan Mammarella, Giovanni Manca, Per Marklund, Jean-Marc Metzger, Meelis Mölder, Stephen M. Platt, Michel Ramonet, Leonard Rivier, Bert Scheeren, Mahesh Kumar Sha, Paul Smith, Martin Steinbacher, Gabriela Vítková, and Simon Wyss
Atmos. Meas. Tech., 14, 89–116,Short summary
The Integrated Carbon Observation System (ICOS) is a pan-European research infrastructure which provides harmonized and high-precision scientific data on the carbon cycle and the greenhouse gas (GHG) budget. All stations have to undergo a rigorous assessment before being labeled, i.e., receiving approval to join the network. In this paper, we present the labeling process for the ICOS atmospheric network through the 23 stations that were labeled between November 2017 and November 2019.
Robbie Ramsay, Chiara F. Di Marco, Matthias Sörgel, Mathew R. Heal, Samara Carbone, Paulo Artaxo, Alessandro C. de Araùjo, Marta Sá, Christopher Pöhlker, Jost Lavric, Meinrat O. Andreae, and Eiko Nemitz
Atmos. Chem. Phys., 20, 15551–15584,Short summary
The Amazon rainforest is a unique
laboratoryto study the processes which govern the exchange of gases and aerosols to and from the atmosphere. This study investigated these processes by measuring the atmospheric concentrations of trace gases and particles at the Amazon Tall Tower Observatory. We found that the long-range transport of pollutants can affect the atmospheric composition above the Amazon rainforest and that the gases ammonia and nitrous acid can be emitted from the rainforest.
Helmi-Marja Keskinen, Ilona Ylivinkka, Liine Heikkinen, Pasi P. Aalto, Tuomo Nieminen, Katrianne Lehtipalo, Juho Aalto, Janne Levula, Jutta Kesti, Lauri R. Ahonen, Ekaterina Ezhova, Markku Kulmala, and Tuukka Petäjä
Atmos. Meas. Tech. Discuss.,
Publication in AMT not foreseenShort summary
Long-term (2005–2017) aerosol particulate matter (PM) concentration measurements at Finland at Station for Measuring Ecosystem-Atmosphere Relations (SMEAR II, Hyytiälä) have been measured with three different measurement equipment. The comparison revealed an equivalence among the three methods. Mass concentrations were generally highest in summer. The descending trend was visible here in spring, summer and winter. This might have resulted at least partly from air quality legislation.
Juan Andrés Casquero-Vera, Hassan Lyamani, Lubna Dada, Simo Hakala, Pauli Paasonen, Roberto Román, Roberto Fraile, Tuukka Petäjä, Francisco José Olmo-Reyes, and Lucas Alados-Arboledas
Atmos. Chem. Phys., 20, 14253–14271,Short summary
New particle formation was investigated at two stations located close to each other but at different altitudes: urban and high-altitude sites. Results show that sulfuric acid is able to explain a minimal fraction contribution to the observed growth rates and point to the availability of volatile organic compounds as the main factor controlling NPF events at both sites. A closer analysis of the NPF events that were observed at high-altitude sites during a Saharan dust episode was carried out.
Michael Rolletter, Marion Blocquet, Martin Kaminski, Birger Bohn, Hans-Peter Dorn, Andreas Hofzumahaus, Frank Holland, Xin Li, Franz Rohrer, Ralf Tillmann, Robert Wegener, Astrid Kiendler-Scharr, Andreas Wahner, and Hendrik Fuchs
Atmos. Chem. Phys., 20, 13701–13719,Short summary
The photooxidation of pinonaldehyde is investigated in a chamber study under natural sunlight and low NO conditions with and without an added hydroxyl radical (OH) scavenger. The experimentally determined pinonaldehyde photolysis frequency is faster by a factor of 3.5 than currently used parameterizations in atmospheric models. Yields of degradation products are measured in the presence and absence of OH. Measurements are compared to current atmospheric models and a theory-based mechanism.
Yongchun Liu, Yusheng Zhang, Chaofan Lian, Chao Yan, Zeming Feng, Feixue Zheng, Xiaolong Fan, Yan Chen, Weigang Wang, Biwu Chu, Yonghong Wang, Jing Cai, Wei Du, Kaspar R. Daellenbach, Juha Kangasluoma, Federico Bianchi, Joni Kujansuu, Tuukka Petäjä, Xuefei Wang, Bo Hu, Yuesi Wang, Maofa Ge, Hong He, and Markku Kulmala
Atmos. Chem. Phys., 20, 13023–13040,Short summary
Understanding of the chemical and physical processes leading to atmospheric aerosol particle formation is crucial to devising effective mitigation strategies to protect the public and reduce uncertainties in climate predictions. We found that the photolysis of nitrous acid could promote the formation of organic and nitrate aerosol and that traffic-related emission is a major contributor to ambient nitrous acid on haze days in wintertime in Beijing.
Jing Cai, Biwu Chu, Lei Yao, Chao Yan, Liine M. Heikkinen, Feixue Zheng, Chang Li, Xiaolong Fan, Shaojun Zhang, Daoyuan Yang, Yonghong Wang, Tom V. Kokkonen, Tommy Chan, Ying Zhou, Lubna Dada, Yongchun Liu, Hong He, Pauli Paasonen, Joni T. Kujansuu, Tuukka Petäjä, Claudia Mohr, Juha Kangasluoma, Federico Bianchi, Yele Sun, Philip L. Croteau, Douglas R. Worsnop, Veli-Matti Kerminen, Wei Du, Markku Kulmala, and Kaspar R. Daellenbach
Atmos. Chem. Phys., 20, 12721–12740,Short summary
By applying both OA PMF and size PMF at the same urban measurement site in Beijing, similar particle source types, including vehicular emissions, cooking emissions and secondary formation-related sources, were resolved by both frameworks and agreed well. It is also found that in the absence of new particle formation, vehicular and cooking emissions dominate the particle number concentration, while secondary particulate matter governed PM2.5 mass during spring and summer in Beijing.
Bettina Hottmann, Sascha Hafermann, Laura Tomsche, Daniel Marno, Monica Martinez, Hartwig Harder, Andrea Pozzer, Marco Neumaier, Andreas Zahn, Birger Bohn, Greta Stratmann, Helmut Ziereis, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 20, 12655–12673,Short summary
During OMO we observed enhanced mixing ratios of hydroperoxides (ROOH) in the Asian monsoon anticyclone (AMA) relative to the background. The observed mixing ratios are higher than steady-state calculations and EMAC simulations, especially in the AMA, indicating atmospheric transport of ROOH. Uncertainties in the scavenging efficiencies likely cause deviations from EMAC. Longitudinal gradients indicate a pool of ROOH towards the center of the AMA associated with upwind convection over India.
Nils Friedrich, Ivan Tadic, Jan Schuladen, James Brooks, Eoghan Darbyshire, Frank Drewnick, Horst Fischer, Jos Lelieveld, and John N. Crowley
Atmos. Meas. Tech., 13, 5739–5761,Short summary
We present a new instrument for the measurement of NOx and NOy based on a combination of the thermal dissociation of NOy to NOx and cavity ring-down spectroscopic detection of NO2. It features a denuder to separate the contributions of gas-phase and particulate nitrates to NOy. We provide a detailed characterization of the instrument and briefly outline results from first deployments.
Marcel Weloe and Thorsten Hoffmann
Atmos. Meas. Tech., 13, 5725–5738,Short summary
Aerosol mass spectrometers (AMSs) are frequently applied in atmospheric aerosol research in connection with climate, environmental or health-related projects. The paper describes a new real-time technique for the measurement of organic peroxides, which play an important role in new particle formation and as
reactive oxygen speciesin aerosol–health-related aspects of atmospheric aerosols.
Ilona Ylivinkka, Santeri Kaupinmäki, Meri Virman, Maija Peltola, Ditte Taipale, Tuukka Petäjä, Veli-Matti Kerminen, Markku Kulmala, and Ekaterina Ezhova
Atmos. Meas. Tech., 13, 5595–5619,Short summary
In this study, we developed a new algorithm for cloud classification using solar radiation and cloud base height measurements. Our objective was to develop a simple and inexpensive but effective algorithm for the needs of studies related to ecosystem and atmosphere interactions. In the present study, we used the algorithm for obtaining cloud statistics at a measurement station in southern Finland, and we discuss the advantages and shortcomings of the algorithm.
Janne Lampilahti, Hanna Elina Manninen, Katri Leino, Riikka Väänänen, Antti Manninen, Stephany Buenrostro Mazon, Tuomo Nieminen, Matti Leskinen, Joonas Enroth, Marja Bister, Sergej Zilitinkevich, Juha Kangasluoma, Heikki Järvinen, Veli-Matti Kerminen, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 20, 11841–11854,Short summary
In this work, by using co-located airborne and ground-based measurements, we show that counter-rotating horizontal circulations in the planetary boundary layer (roll vortices) frequently enhance regional new particle formation or induce localized bursts of new particle formation. These observations can be explained by the ability of the rolls to efficiently lift low-volatile vapors emitted from the surface to the top of the boundary layer where new particle formation is more favorable.
Martin Heinritzi, Lubna Dada, Mario Simon, Dominik Stolzenburg, Andrea C. Wagner, Lukas Fischer, Lauri R. Ahonen, Stavros Amanatidis, Rima Baalbaki, Andrea Baccarini, Paulus S. Bauer, Bernhard Baumgartner, Federico Bianchi, Sophia Brilke, Dexian Chen, Randall Chiu, Antonio Dias, Josef Dommen, Jonathan Duplissy, Henning Finkenzeller, Carla Frege, Claudia Fuchs, Olga Garmash, Hamish Gordon, Manuel Granzin, Imad El Haddad, Xucheng He, Johanna Helm, Victoria Hofbauer, Christopher R. Hoyle, Juha Kangasluoma, Timo Keber, Changhyuk Kim, Andreas Kürten, Houssni Lamkaddam, Tiia M. Laurila, Janne Lampilahti, Chuan Ping Lee, Katrianne Lehtipalo, Markus Leiminger, Huajun Mai, Vladimir Makhmutov, Hanna Elina Manninen, Ruby Marten, Serge Mathot, Roy Lee Mauldin, Bernhard Mentler, Ugo Molteni, Tatjana Müller, Wei Nie, Tuomo Nieminen, Antti Onnela, Eva Partoll, Monica Passananti, Tuukka Petäjä, Joschka Pfeifer, Veronika Pospisilova, Lauriane L. J. Quéléver, Matti P. Rissanen, Clémence Rose, Siegfried Schobesberger, Wiebke Scholz, Kay Scholze, Mikko Sipilä, Gerhard Steiner, Yuri Stozhkov, Christian Tauber, Yee Jun Tham, Miguel Vazquez-Pufleau, Annele Virtanen, Alexander L. Vogel, Rainer Volkamer, Robert Wagner, Mingyi Wang, Lena Weitz, Daniela Wimmer, Mao Xiao, Chao Yan, Penglin Ye, Qiaozhi Zha, Xueqin Zhou, Antonio Amorim, Urs Baltensperger, Armin Hansel, Markku Kulmala, António Tomé, Paul M. Winkler, Douglas R. Worsnop, Neil M. Donahue, Jasper Kirkby, and Joachim Curtius
Atmos. Chem. Phys., 20, 11809–11821,Short summary
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.
Ting Lei, Nan Ma, Juan Hong, Thomas Tuch, Xin Wang, Zhibin Wang, Mira Pöhlker, Maofa Ge, Weigang Wang, Eugene Mikhailov, Thorsten Hoffmann, Ulrich Pöschl, Hang Su, Alfred Wiedensohler, and Yafang Cheng
Atmos. Meas. Tech., 13, 5551–5567,Short summary
We present the design of a nano-hygroscopicity tandem differential mobility analyzer (nano-HTDMA) apparatus that enables high accuracy and precision in hygroscopic growth measurements of aerosol nanoparticles with diameters less than 10 nm. We further introduce comprehensive methods for system calibration and validation of the performance of the system. We then study the size dependence of the deliquescence and the efflorescence of aerosol nanoparticles for sizes down to 6 nm.
Lubna Dada, Ilona Ylivinkka, Rima Baalbaki, Chang Li, Yishuo Guo, Chao Yan, Lei Yao, Nina Sarnela, Tuija Jokinen, Kaspar R. Daellenbach, Rujing Yin, Chenjuan Deng, Biwu Chu, Tuomo Nieminen, Yonghong Wang, Zhuohui Lin, Roseline C. Thakur, Jenni Kontkanen, Dominik Stolzenburg, Mikko Sipilä, Tareq Hussein, Pauli Paasonen, Federico Bianchi, Imre Salma, Tamás Weidinger, Michael Pikridas, Jean Sciare, Jingkun Jiang, Yongchun Liu, Tuukka Petäjä, Veli-Matti Kerminen, and Markku Kulmala
Atmos. Chem. Phys., 20, 11747–11766,Short summary
We rely on sulfuric acid measurements in four contrasting environments, Hyytiälä, Finland; Agia Marina, Cyprus; Budapest, Hungary; and Beijing, China, representing semi-pristine boreal forest, rural environment in the Mediterranean area, urban environment, and heavily polluted megacity, respectively, in order to define the sources and sinks of sulfuric acid in these environments and to derive a new sulfuric acid proxy to be utilized in locations and during periods when it is not measured.
Jenni Kontkanen, Chenjuan Deng, Yueyun Fu, Lubna Dada, Ying Zhou, Jing Cai, Kaspar R. Daellenbach, Simo Hakala, Tom V. Kokkonen, Zhuohui Lin, Yongchun Liu, Yonghong Wang, Chao Yan, Tuukka Petäjä, Jingkun Jiang, Markku Kulmala, and Pauli Paasonen
Atmos. Chem. Phys., 20, 11329–11348,Short summary
To estimate the impacts of atmospheric aerosol particles on air quality, knowledge of size distributions of particles emitted from anthropogenic sources is needed. We introduce a new method for determining size-resolved particle number emissions from measured particle size distributions. We apply our method to data measured in Beijing, China. We find that particle number emissions at our site are dominated by emissions of particles smaller than 30 nm, originating mainly from traffic.
Ingeborg Levin, Ute Karstens, Markus Eritt, Fabian Maier, Sabrina Arnold, Daniel Rzesanke, Samuel Hammer, Michel Ramonet, Gabriela Vítková, Sebastien Conil, Michal Heliasz, Dagmar Kubistin, and Matthias Lindauer
Atmos. Chem. Phys., 20, 11161–11180,Short summary
Based on observations and Stochastic Time-Inverted Lagrangian Transport (STILT) footprint modelling, a sampling strategy has been developed for tall tower stations of the Integrated Carbon Observation System (ICOS) research infrastructure atmospheric station network. This strategy allows independent quality control of in situ measurements, provides representative coverage of the influence area of the sites, and is capable of automated targeted sampling of fossil fuel CO2 emission hotspots.
Arnaud P. Praplan, Toni Tykkä, Simon Schallhart, Virpi Tarvainen, Jaana Bäck, and Heidi Hellén
Biogeosciences, 17, 4681–4705,Short summary
In this paper, we study emissions of volatile organic compounds (VOCs) from three boreal tree species. Individual compounds are quantified with on-line separation analytical techniques, while the total reactivity of the emissions is measured using a custom-built instrument. On some occasions, in particular when the trees suffer from stress, the total reactivity measured is higher than the sum of the reactivity of individual compounds. This indicates that the threes emit VOCs that remain unknown.
Nijing Wang, Achim Edtbauer, Christof Stönner, Andrea Pozzer, Efstratios Bourtsoukidis, Lisa Ernle, Dirk Dienhart, Bettina Hottmann, Horst Fischer, Jan Schuladen, John N. Crowley, Jean-Daniel Paris, Jos Lelieveld, and Jonathan Williams
Atmos. Chem. Phys., 20, 10807–10829,Short summary
Carbonyl compounds were measured on a ship travelling around the Arabian Peninsula in summer 2017, crossing both highly polluted and extremely clean regions of the marine boundary layer. We investigated the sources and sinks of carbonyls. The results from a global model showed a significant model underestimation for acetaldehyde, a molecule that can influence regional air chemistry. By adding a diurnal oceanic source, the model estimation was highly improved.
Patrick Dewald, Jonathan M. Liebmann, Nils Friedrich, Justin Shenolikar, Jan Schuladen, Franz Rohrer, David Reimer, Ralf Tillmann, Anna Novelli, Changmin Cho, Kangming Xu, Rupert Holzinger, François Bernard, Li Zhou, Wahid Mellouki, Steven S. Brown, Hendrik Fuchs, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 20, 10459–10475,Short summary
We present direct measurements of NO3 reactivity resulting from the oxidation of isoprene by NO3 during an intensive simulation chamber study. Measurements were in excellent agreement with values calculated from measured isoprene amounts and the rate coefficient for the reaction of NO3 with isoprene. Comparison of the measurement with NO3 reactivities from non-steady-state and model calculations suggests that isoprene-derived RO2 and HO2 radicals account to ~ 50 % of overall NO3 losses.
Paolo Laj, Alessandro Bigi, Clémence Rose, Elisabeth Andrews, Cathrine Lund Myhre, Martine Collaud Coen, Yong Lin, Alfred Wiedensohler, Michael Schulz, John A. Ogren, Markus Fiebig, Jonas Gliß, Augustin Mortier, Marco Pandolfi, Tuukka Petäja, Sang-Woo Kim, Wenche Aas, Jean-Philippe Putaud, Olga Mayol-Bracero, Melita Keywood, Lorenzo Labrador, Pasi Aalto, Erik Ahlberg, Lucas Alados Arboledas, Andrés Alastuey, Marcos Andrade, Begoña Artíñano, Stina Ausmeel, Todor Arsov, Eija Asmi, John Backman, Urs Baltensperger, Susanne Bastian, Olaf Bath, Johan Paul Beukes, Benjamin T. Brem, Nicolas Bukowiecki, Sébastien Conil, Cedric Couret, Derek Day, Wan Dayantolis, Anna Degorska, Konstantinos Eleftheriadis, Prodromos Fetfatzis, Olivier Favez, Harald Flentje, Maria I. Gini, Asta Gregorič, Martin Gysel-Beer, A. Gannet Hallar, Jenny Hand, Andras Hoffer, Christoph Hueglin, Rakesh K. Hooda, Antti Hyvärinen, Ivo Kalapov, Nikos Kalivitis, Anne Kasper-Giebl, Jeong Eun Kim, Giorgos Kouvarakis, Irena Kranjc, Radovan Krejci, Markku Kulmala, Casper Labuschagne, Hae-Jung Lee, Heikki Lihavainen, Neng-Huei Lin, Gunter Löschau, Krista Luoma, Angela Marinoni, Sebastiao Martins Dos Santos, Frank Meinhardt, Maik Merkel, Jean-Marc Metzger, Nikolaos Mihalopoulos, Nhat Anh Nguyen, Jakub Ondracek, Noemi Pérez, Maria Rita Perrone, Jean-Eudes Petit, David Picard, Jean-Marc Pichon, Veronique Pont, Natalia Prats, Anthony Prenni, Fabienne Reisen, Salvatore Romano, Karine Sellegri, Sangeeta Sharma, Gerhard Schauer, Patrick Sheridan, James Patrick Sherman, Maik Schütze, Andreas Schwerin, Ralf Sohmer, Mar Sorribas, Martin Steinbacher, Junying Sun, Gloria Titos, Barbara Toczko, Thomas Tuch, Pierre Tulet, Peter Tunved, Ville Vakkari, Fernando Velarde, Patricio Velasquez, Paolo Villani, Sterios Vratolis, Sheng-Hsiang Wang, Kay Weinhold, Rolf Weller, Margarita Yela, Jesus Yus-Diez, Vladimir Zdimal, Paul Zieger, and Nadezda Zikova
Atmos. Meas. Tech., 13, 4353–4392,Short summary
The paper establishes the fiducial reference of the GAW aerosol network providing the fully characterized value chain to the provision of four climate-relevant aerosol properties from ground-based sites. Data from almost 90 stations worldwide are reported for a reference year, 2017, providing a unique and very robust view of the variability of these variables worldwide. Current gaps in the GAW network are analysed and requirements for the Global Climate Monitoring System are proposed.
Mario Simon, Lubna Dada, Martin Heinritzi, Wiebke Scholz, Dominik Stolzenburg, Lukas Fischer, Andrea C. Wagner, Andreas Kürten, Birte Rörup, Xu-Cheng He, João Almeida, Rima Baalbaki, Andrea Baccarini, Paulus S. Bauer, Lisa Beck, Anton Bergen, Federico Bianchi, Steffen Bräkling, Sophia Brilke, Lucia Caudillo, Dexian Chen, Biwu Chu, António Dias, Danielle C. Draper, Jonathan Duplissy, Imad El-Haddad, Henning Finkenzeller, Carla Frege, Loic Gonzalez-Carracedo, Hamish Gordon, Manuel Granzin, Jani Hakala, Victoria Hofbauer, Christopher R. Hoyle, Changhyuk Kim, Weimeng Kong, Houssni Lamkaddam, Chuan P. Lee, Katrianne Lehtipalo, Markus Leiminger, Huajun Mai, Hanna E. Manninen, Guillaume Marie, Ruby Marten, Bernhard Mentler, Ugo Molteni, Leonid Nichman, Wei Nie, Andrea Ojdanic, Antti Onnela, Eva Partoll, Tuukka Petäjä, Joschka Pfeifer, Maxim Philippov, Lauriane L. J. Quéléver, Ananth Ranjithkumar, Matti P. Rissanen, Simon Schallhart, Siegfried Schobesberger, Simone Schuchmann, Jiali Shen, Mikko Sipilä, Gerhard Steiner, Yuri Stozhkov, Christian Tauber, Yee J. Tham, António R. Tomé, Miguel Vazquez-Pufleau, Alexander L. Vogel, Robert Wagner, Mingyi Wang, Dongyu S. Wang, Yonghong Wang, Stefan K. Weber, Yusheng Wu, Mao Xiao, Chao Yan, Penglin Ye, Qing Ye, Marcel Zauner-Wieczorek, Xueqin Zhou, Urs Baltensperger, Josef Dommen, Richard C. Flagan, Armin Hansel, Markku Kulmala, Rainer Volkamer, Paul M. Winkler, Douglas R. Worsnop, Neil M. Donahue, Jasper Kirkby, and Joachim Curtius
Atmos. Chem. Phys., 20, 9183–9207,Short summary
Highly oxygenated organic compounds (HOMs) have been identified as key vapors involved in atmospheric new-particle formation (NPF). The molecular distribution, HOM yield, and NPF from α-pinene oxidation experiments were measured at the CLOUD chamber over a wide tropospheric-temperature range. This study shows on a molecular scale that despite the sharp reduction in HOM yield at lower temperatures, the reduced volatility counteracts this effect and leads to an overall increase in the NPF rate.
Ru-Jin Huang, Yao He, Jing Duan, Yongjie Li, Qi Chen, Yan Zheng, Yang Chen, Weiwei Hu, Chunshui Lin, Haiyan Ni, Wenting Dai, Junji Cao, Yunfei Wu, Renjian Zhang, Wei Xu, Jurgita Ovadnevaite, Darius Ceburnis, Thorsten Hoffmann, and Colin D. O'Dowd
Atmos. Chem. Phys., 20, 9101–9114,Short summary
We systematically compared the submicron particle (PM1) processes in haze days with low and high relative humidity (RH) in wintertime Beijing. Nitrate had similar daytime growth rates in low-RH and high-RH pollution. OOA had a higher growth rate in low-RH pollution than in high-RH pollution. Sulfate had a decreasing trend in low-RH pollution, while it increased significantly in high-RH pollution. This distinction may be explained by the different processes affected by meteorological conditions.
Tuukka Petäjä, Ella-Maria Duplissy, Ksenia Tabakova, Julia Schmale, Barbara Altstädter, Gerard Ancellet, Mikhail Arshinov, Yurii Balin, Urs Baltensperger, Jens Bange, Alison Beamish, Boris Belan, Antoine Berchet, Rossana Bossi, Warren R. L. Cairns, Ralf Ebinghaus, Imad El Haddad, Beatriz Ferreira-Araujo, Anna Franck, Lin Huang, Antti Hyvärinen, Angelika Humbert, Athina-Cerise Kalogridis, Pavel Konstantinov, Astrid Lampert, Matthew MacLeod, Olivier Magand, Alexander Mahura, Louis Marelle, Vladimir Masloboev, Dmitri Moisseev, Vaios Moschos, Niklas Neckel, Tatsuo Onishi, Stefan Osterwalder, Aino Ovaska, Pauli Paasonen, Mikhail Panchenko, Fidel Pankratov, Jakob B. Pernov, Andreas Platis, Olga Popovicheva, Jean-Christophe Raut, Aurélie Riandet, Torsten Sachs, Rosamaria Salvatori, Roberto Salzano, Ludwig Schröder, Martin Schön, Vladimir Shevchenko, Henrik Skov, Jeroen E. Sonke, Andrea Spolaor, Vasileios K. Stathopoulos, Mikko Strahlendorff, Jennie L. Thomas, Vito Vitale, Sterios Vratolis, Carlo Barbante, Sabine Chabrillat, Aurélien Dommergue, Konstantinos Eleftheriadis, Jyri Heilimo, Kathy S. Law, Andreas Massling, Steffen M. Noe, Jean-Daniel Paris, André S. H. Prévôt, Ilona Riipinen, Birgit Wehner, Zhiyong Xie, and Hanna K. Lappalainen
Atmos. Chem. Phys., 20, 8551–8592,Short summary
The role of polar regions is increasing in terms of megatrends such as globalization, new transport routes, demography, and the use of natural resources with consequent effects on regional and transported pollutant concentrations. Here we summarize initial results from our integrative project exploring the Arctic environment and pollution to deliver data products, metrics, and indicators for stakeholders.
Yuan Yang, Yonghong Wang, Putian Zhou, Dan Yao, Dongsheng Ji, Jie Sun, Yinghong Wang, Shuman Zhao, Wei Huang, Shuanghong Yang, Dean Chen, Wenkang Gao, Zirui Liu, Bo Hu, Renjian Zhang, Limin Zeng, Maofa Ge, Tuukka Petäjä, Veli-Matti Kerminen, Markku Kulmala, and Yuesi Wang
Atmos. Chem. Phys., 20, 8181–8200,
Dominik Stolzenburg, Mario Simon, Ananth Ranjithkumar, Andreas Kürten, Katrianne Lehtipalo, Hamish Gordon, Sebastian Ehrhart, Henning Finkenzeller, Lukas Pichelstorfer, Tuomo Nieminen, Xu-Cheng He, Sophia Brilke, Mao Xiao, António Amorim, Rima Baalbaki, Andrea Baccarini, Lisa Beck, Steffen Bräkling, Lucía Caudillo Murillo, Dexian Chen, Biwu Chu, Lubna Dada, António Dias, Josef Dommen, Jonathan Duplissy, Imad El Haddad, Lukas Fischer, Loic Gonzalez Carracedo, Martin Heinritzi, Changhyuk Kim, Theodore K. Koenig, Weimeng Kong, Houssni Lamkaddam, Chuan Ping Lee, Markus Leiminger, Zijun Li, Vladimir Makhmutov, Hanna E. Manninen, Guillaume Marie, Ruby Marten, Tatjana Müller, Wei Nie, Eva Partoll, Tuukka Petäjä, Joschka Pfeifer, Maxim Philippov, Matti P. Rissanen, Birte Rörup, Siegfried Schobesberger, Simone Schuchmann, Jiali Shen, Mikko Sipilä, Gerhard Steiner, Yuri Stozhkov, Christian Tauber, Yee Jun Tham, António Tomé, Miguel Vazquez-Pufleau, Andrea C. Wagner, Mingyi Wang, Yonghong Wang, Stefan K. Weber, Daniela Wimmer, Peter J. Wlasits, Yusheng Wu, Qing Ye, Marcel Zauner-Wieczorek, Urs Baltensperger, Kenneth S. Carslaw, Joachim Curtius, Neil M. Donahue, Richard C. Flagan, Armin Hansel, Markku Kulmala, Jos Lelieveld, Rainer Volkamer, Jasper Kirkby, and Paul M. Winkler
Atmos. Chem. Phys., 20, 7359–7372,Short summary
Sulfuric acid is a major atmospheric vapour for aerosol formation. If new particles grow fast enough, they can act as cloud droplet seeds or affect air quality. In a controlled laboratory set-up, we demonstrate that van der Waals forces enhance growth from sulfuric acid. We disentangle the effects of ammonia, ions and particle hydration, presenting a complete picture of sulfuric acid growth from molecular clusters onwards. In a climate model, we show its influence on the global aerosol budget.
Ivan Tadic, John N. Crowley, Dirk Dienhart, Philipp Eger, Hartwig Harder, Bettina Hottmann, Monica Martinez, Uwe Parchatka, Jean-Daniel Paris, Andrea Pozzer, Roland Rohloff, Jan Schuladen, Justin Shenolikar, Sebastian Tauer, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 20, 6769–6787,Short summary
We present shipborne observations of NO, NO2, O3, HCHO, OH, HO2, H2O and the actinic flux obtained in the marine boundary layer (MBL) around the Arabian Peninsula during the summer 2017 AQABA ship campaign. NOx (NO+NO2) and O3 observations clearly showed anthropogenic influence in the MBL around the Arabian Peninsula. The observations were also used to calculate net O3 production in the MBL around the Arabian Peninsula, which was greatest over the northern Red Sea, Oman Gulf and Arabian Gulf.
Mikhail Paramonov, Saskia Drossaart van Dusseldorp, Ellen Gute, Jonathan P. D. Abbatt, Paavo Heikkilä, Jorma Keskinen, Xuemeng Chen, Krista Luoma, Liine Heikkinen, Liqing Hao, Tuukka Petäjä, and Zamin A. Kanji
Atmos. Chem. Phys., 20, 6687–6706,Short summary
Ice-nucleating particle (INP) measurements were performed in the boreal environment of southern Finland in the winter–spring of 2018. It was found that no single parameter could be used to predict the INP number concentration at the measurement location during the examined time period. It was also not possible to identify physical and chemical properties of ambient INPs despite the complexity of the instrumental set-up. Therefore, this paper addresses the necessity for future INP measurements.
Daniel Marno, Cheryl Ernest, Korbinian Hens, Umar Javed, Thomas Klimach, Monica Martinez, Markus Rudolf, Jos Lelieveld, and Hartwig Harder
Atmos. Meas. Tech., 13, 2711–2731,Short summary
In this study, a calibration device for OH and HO2 instruments is characterized at pressures of 275 to 1000 mbar, allowing instrument pressure sensitivity to be quantified to an accuracy of 22 % (1σ). Computational fluid dynamic simulations supporting the understanding of interactions between generated HOx and the instrument inlet led to enhanced determination of factors affecting instrument sensitivity.
Achim Edtbauer, Christof Stönner, Eva Y. Pfannerstill, Matias Berasategui, David Walter, John N. Crowley, Jos Lelieveld, and Jonathan Williams
Atmos. Chem. Phys., 20, 6081–6094,Short summary
Marine regions where deep nutrient-rich water is pushed towards the surface are called upwelling regions. In these nutrient-rich waters large algal blooms form which are the basis of the marine food web. We measured methane sulfonamide, a molecule containing sulfur and nitrogen, for the first time in ambient air and could show that the origin of this emission is an algal bloom near the Somalia upwelling. Sulfur-containing compounds from algae can promote particle formation over the oceans.
Wei Yuan, Ru-Jin Huang, Lu Yang, Jie Guo, Ziyi Chen, Jing Duan, Ting Wang, Haiyan Ni, Yongming Han, Yongjie Li, Qi Chen, Yang Chen, Thorsten Hoffmann, and Colin O'Dowd
Atmos. Chem. Phys., 20, 5129–5144,Short summary
We characterized light-absorbing properties, chromophore composition and sources of brown carbon (BrC) in Xi'an; identified three groups of light-absorbing organics; and quantified their contribution to overall BrC absorption. Our results showed that vehicle emissions and secondary formation are major sources of BrC in spring, coal combustion and vehicle emissions are major sources in fall, biomass burning and coal combustion become major sources in winter, and secondary BrC dominates in summer.
Bruna A. Holanda, Mira L. Pöhlker, David Walter, Jorge Saturno, Matthias Sörgel, Jeannine Ditas, Florian Ditas, Christiane Schulz, Marco Aurélio Franco, Qiaoqiao Wang, Tobias Donth, Paulo Artaxo, Henrique M. J. Barbosa, Stephan Borrmann, Ramon Braga, Joel Brito, Yafang Cheng, Maximilian Dollner, Johannes W. Kaiser, Thomas Klimach, Christoph Knote, Ovid O. Krüger, Daniel Fütterer, Jošt V. Lavrič, Nan Ma, Luiz A. T. Machado, Jing Ming, Fernando G. Morais, Hauke Paulsen, Daniel Sauer, Hans Schlager, Johannes Schneider, Hang Su, Bernadett Weinzierl, Adrian Walser, Manfred Wendisch, Helmut Ziereis, Martin Zöger, Ulrich Pöschl, Meinrat O. Andreae, and Christopher Pöhlker
Atmos. Chem. Phys., 20, 4757–4785,Short summary
Biomass burning smoke from African savanna and grassland is transported across the South Atlantic Ocean in defined layers within the free troposphere. The combination of in situ aircraft and ground-based measurements aided by satellite observations showed that these layers are transported into the Amazon Basin during the early dry season. The influx of aged smoke, enriched in black carbon and cloud condensation nuclei, has important implications for the Amazonian aerosol and cloud cycling.
Siddika Celik, Frank Drewnick, Friederike Fachinger, James Brooks, Eoghan Darbyshire, Hugh Coe, Jean-Daniel Paris, Philipp G. Eger, Jan Schuladen, Ivan Tadic, Nils Friedrich, Dirk Dienhart, Bettina Hottmann, Horst Fischer, John N. Crowley, Hartwig Harder, and Stephan Borrmann
Atmos. Chem. Phys., 20, 4713–4734,Short summary
Analysis of 252 ship emission plumes in the Mediterranean Sea and around the Arabian Peninsula examined particulate- and gas-phase characteristics. By identifying the corresponding ships, source features and plume age were determined. Emission factors (amount of pollutant per kilogram of fuel burned) were calculated and investigated for dependencies on source characteristics, atmospheric conditions, and transport time, providing insight into the most relevant influences on ship emissions.
Dean Chen, Putian Zhou, Tuomo Nieminen, Pontus Roldin, Ximeng Qi, Petri Clusius, Carlton Xavier, Lukas Pichelstorfer, Markku Kulmala, Pekka Rantala, Juho Aalto, Nina Sarnela, Pasi Kolari, Petri Keronen, Matti P. Rissanen, Metin Baykara, and Michael Boy
Atmos. Chem. Phys. Discuss.,
Preprint withdrawnShort summary
Atmospheric oxidants OH, O3 and NO3 dominate the atmospheric oxidation capacity, and sulfuric acid (H2SO4) is considered as a main driver for new particle formation events. We studied how the trends of these atmospheric oxidants and H2SO4 changed in southern Finland during the past 12 years and discussed how these trends related to decreasing emissions of air pollutants in Europe. Our results showed that OH increased by 1.56 % yr−1 at daytime and NO3 decreased by 3.92 % yr−1 at nighttime.
Stefano Decesari, Marco Paglione, Matteo Rinaldi, Manuel Dall'Osto, Rafel Simó, Nicola Zanca, Francesca Volpi, Maria Cristina Facchini, Thorsten Hoffmann, Sven Götz, Christopher Johannes Kampf, Colin O'Dowd, Darius Ceburnis, Jurgita Ovadnevaite, and Emilio Tagliavini
Atmos. Chem. Phys., 20, 4193–4207,Short summary
Atmospheric aerosols in Antarctica contribute to regulate the delicate budget of cloud formation and precipitations. Besides the well-known biogenic production of sulfur-containing aerosol components such as methanesulfonate (MSA), the assessment of biological sources of organic particles in Antarctica remains an active area of research. Here we present the results of aerosol organic characterization during a research cruise performed in the Weddell Sea and in the Southern Ocean in Jan–Feb 2015.
Jing Duan, Ru-Jin Huang, Yongjie Li, Qi Chen, Yan Zheng, Yang Chen, Chunshui Lin, Haiyan Ni, Meng Wang, Jurgita Ovadnevaite, Darius Ceburnis, Chunying Chen, Douglas R. Worsnop, Thorsten Hoffmann, Colin O'Dowd, and Junji Cao
Atmos. Chem. Phys., 20, 3793–3807,Short summary
We characterized secondary aerosol formation in Beijing. Our results showed that relative humidity (RH) and Ox have opposite effects on sulfate and nitrate formation in summer and winter. The wintertime more-oxidized OOA (MO-OOA) showed a good correlation with aerosol liquid water content (ALWC). Meanwhile, the dependence of less-oxidized OOA (LO-OOA) and the mass ratio of LO-OOA to MO-OOA in Ox both degraded when RH > 60 %, suggesting that RH or ALWC may also affect LO-OOA formation.
Philipp G. Eger, Jan Schuladen, Nicolas Sobanski, Horst Fischer, Einar Karu, Jonathan Williams, Matthieu Riva, Qiaozhi Zha, Mikael Ehn, Lauriane L. J. Quéléver, Simon Schallhart, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 20, 3697–3711,Short summary
Pyruvic acid, CH3C(O)C(O)OH, is an organic acid of biogenic origin that plays a crucial role in plant metabolism, is present in tropospheric air in both gas-phase and aerosol-phase, and is implicated in the formation of secondary organic aerosols. From the first gas-phase measurements of pyruvic acid in the Finnish boreal forest in September 2016 we derive its source strength and discuss potential sources and sinks, with a focus on the relevance of gas-phase pyruvic acid for radical chemistry.
Laura Matkala, Maija Salemaa, and Jaana Bäck
Biogeosciences, 17, 1535–1556,Short summary
We studied how species number and abundance of the understorey vegetation correlates with nutrient contents of soil and tree leaves at a northern boreal forest site. The phosphorus (P) content of the humus layer showed higher correlation with vegetation than the nitrogen (N) content. Usually N is considered more important in boreal forests. The plots with high P content in humus had birch as the dominant tree species, implying that birch leaf litter is an important source of P to the plants.
Anna Novelli, Luc Vereecken, Birger Bohn, Hans-Peter Dorn, Georgios I. Gkatzelis, Andreas Hofzumahaus, Frank Holland, David Reimer, Franz Rohrer, Simon Rosanka, Domenico Taraborrelli, Ralf Tillmann, Robert Wegener, Zhujun Yu, Astrid Kiendler-Scharr, Andreas Wahner, and Hendrik Fuchs
Atmos. Chem. Phys., 20, 3333–3355,Short summary
Experimental evidence from a simulation chamber study shows that the regeneration efficiency of the hydroxyl radical is maintained globally at values higher than 0.5 for a wide range of nitrogen oxide concentrations as a result of isomerizations of peroxy radicals originating from the OH oxidation of isoprene. The available models were tested, and suggestions on how to improve their ability to reproduce the measured radical and oxygenated volatile organic compound concentrations are provided.
Liine Heikkinen, Mikko Äijälä, Matthieu Riva, Krista Luoma, Kaspar Dällenbach, Juho Aalto, Pasi Aalto, Diego Aliaga, Minna Aurela, Helmi Keskinen, Ulla Makkonen, Pekka Rantala, Markku Kulmala, Tuukka Petäjä, Douglas Worsnop, and Mikael Ehn
Atmos. Chem. Phys., 20, 3151–3180,Short summary
Atmospheric aerosols are solid or liquid particles suspended in the air. They are known as a health risk, but they also influence the Earth's climate. The composition of aerosols becomes important when predicting their effect on climate. We show both seasonal and year-to-year variability of aerosol chemical composition in the boreal forest of Finland. We observed a consistent bimodal seasonal trend: a biogenic summertime maximum and an anthropogenic wintertime maximum in the mass concentration.
Matias Berasategui, Damien Amedro, Achim Edtbauer, Jonathan Williams, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 20, 2695–2707,Short summary
We have determined the rate coefficient and mechanism for the reaction of the OH radical with methane sulphonamide, a trace gas which has recently been found in the atmosphere. The rate coefficient is 1.4 × 10−13 cm3 molec.−1 s−1, which indicates a tropospheric lifetime of > 2 months. The observation of CO, CO2, SO2, HNO3, HCOOH, and N2O products enabled us to derive a detailed reaction mechanism for the reaction, which proceeds predominantly by H abstraction from the CH3 group.
Ditte Taipale, Juho Aalto, Pauliina Schiestl-Aalto, Markku Kulmala, and Jaana Bäck
Ying Zhou, Lubna Dada, Yiliang Liu, Yueyun Fu, Juha Kangasluoma, Tommy Chan, Chao Yan, Biwu Chu, Kaspar R. Daellenbach, Federico Bianchi, Tom V. Kokkonen, Yongchun Liu, Joni Kujansuu, Veli-Matti Kerminen, Tuukka Petäjä, Lin Wang, Jingkun Jiang, and Markku Kulmala
Atmos. Chem. Phys., 20, 1201–1216,Short summary
In this study, we focus on explaining the concentration variations in the observed particle modes, by relating them to the potential aerosol sources and sinks, and on understanding the connections between these modes. Interestingly, even in the atmospheric cocktail in urban Beijing, secondary new particle formation (NPF) drives the particle number concentration, especially in the sub-3 nm range. We found that the total number concentration is ~ 4 times higher on NPF days than on haze days.
Marja Hemmilä, Ulla Makkonen, Aki Virkkula, Georgia Panagiotopoulou, Juho Aalto, Markku Kulmala, Tuukka Petäjä, Hannele Hakola, and Heidi Hellén
Atmos. Chem. Phys. Discuss.,
Publication in ACP not foreseenShort summary
Amines are atmospheric bases, which can affect to nucleation of aerosols. Lately, a computational study showed that guanidine could be even more effective to stabilize sulphuric acid clusters. In this paper we used a a dynamic flow-through chamber with an online ion chromatograph MARGA coupled with a mass spectrometer (MARGA-MS). We studied amine and guanidine emission from a boreal forest floor in Finland, and find out, that the boreal forest floor is a source of amines and guanidine.
Tanja J. Schuck, Ann-Katrin Blank, Elisa Rittmeier, Jonathan Williams, Carl A. M. Brenninkmeijer, Andreas Engel, and Andreas Zahn
Atmos. Meas. Tech., 13, 73–84,Short summary
Air sample collection aboard aircraft is a tool to measure atmospheric trace gas mixing ratios at altitude. We present results on the stability of 28 halocarbons during storage of air samples collected in stainless-steel flasks inside an automated air sampling unit which is part of the CARIBIC instrument package. Selected fluorinated compounds grew during the experiments while short-lived compounds were depleted. Individual substances were additionally influenced by high mixing ratios of ozone.
Yonghong Wang, Miao Yu, Yuesi Wang, Guiqian Tang, Tao Song, Putian Zhou, Zirui Liu, Bo Hu, Dongsheng Ji, Lili Wang, Xiaowan Zhu, Chao Yan, Mikael Ehn, Wenkang Gao, Yuepeng Pan, Jinyuan Xin, Yang Sun, Veli-Matti Kerminen, Markku Kulmala, and Tuukka Petäjä
Atmos. Chem. Phys., 20, 45–53,Short summary
We found a positive particle matter-mixing layer height feedback at three observation platforms at the 325 m Beijing meteorology tower, which is characterized by a shallower mixing layer height and a higher particle matter concentration. Measurements of solar radiation, aerosol chemical composition, meteorology parameters, trace gases and turbulent kinetic energy (TKE) could explain the feedback mechanism to some extent.
Maurício I. Oliveira, Otávio C. Acevedo, Matthias Sörgel, Ernani L. Nascimento, Antonio O. Manzi, Pablo E. S. Oliveira, Daiane V. Brondani, Anywhere Tsokankunku, and Meinrat O. Andreae
Atmos. Chem. Phys., 20, 15–27,Short summary
In this study, data collected during four deep convection events at the 80 m tower from the Amazon Tall Tower Observatory are analyzed. It provides a unique view on how such events affect the local boundary layer and how it recovers after their passage. Quantities analyzed include mean wind speed, virtual potential temperature, turbulent kinetic energy, sensible, and latent heat fluxes. A conceptual model for boundary layer structure along the passage of deep convection events is proposed.
Yicheng Shen, Aki Virkkula, Aijun Ding, Krista Luoma, Helmi Keskinen, Pasi P. Aalto, Xuguang Chi, Ximeng Qi, Wei Nie, Xin Huang, Tuukka Petäjä, Markku Kulmala, and Veli-Matti Kerminen
Atmos. Chem. Phys., 19, 15483–15502,Short summary
Long-term cloud condensation nuclei (CCN) number concentration (NCCN) data are scarce; there are a lot more data on aerosol optical properties (AOPs). It is therefore valuable to derive parameterizations for estimating NCCN from AOP measurements. With the new parameterization NCCN can be estimated from backscatter fraction, scattering Ångström exponent, and total light-scattering coefficient. The NCCN–AOP relationships depend on the geometric mean diameter and the width of the size distribution.
Arnaud P. Praplan, Toni Tykkä, Dean Chen, Michael Boy, Ditte Taipale, Ville Vakkari, Putian Zhou, Tuukka Petäjä, and Heidi Hellén
Atmos. Chem. Phys., 19, 14431–14453,Short summary
Our study shows that, despite our best efforts and recent progress, our knowledge of the chemical composition of the air under the canopy of a boreal forest still cannot be fully characterized. The discrepancy between the measured total reactivity of the air and the reactivity derived from the known chemical composition highlights the need to better understand the emissions from vegetation, but also other sources, such as the forest soil.
Simonas Kecorius, Teresa Vogl, Pauli Paasonen, Janne Lampilahti, Daniel Rothenberg, Heike Wex, Sebastian Zeppenfeld, Manuela van Pinxteren, Markus Hartmann, Silvia Henning, Xianda Gong, Andre Welti, Markku Kulmala, Frank Stratmann, Hartmut Herrmann, and Alfred Wiedensohler
Atmos. Chem. Phys., 19, 14339–14364,Short summary
Arctic sea-ice retreat, atmospheric new particle formation (NPF), and aerosol–cloud interaction may all be linked via a positive feedback mechanism. Understanding the sources of cloud condensation nuclei (CCN) is an important piece in the Arctic amplification puzzle. We show that Arctic newly formed particles do not have to grow beyond the Aitken mode to act as CCN. This is important, because NPF occurrence in the Arctic is expected to increase, making it a significant contributor to CCN budget.
Philipp G. Eger, Nils Friedrich, Jan Schuladen, Justin Shenolikar, Horst Fischer, Ivan Tadic, Hartwig Harder, Monica Martinez, Roland Rohloff, Sebastian Tauer, Frank Drewnick, Friederike Fachinger, James Brooks, Eoghan Darbyshire, Jean Sciare, Michael Pikridas, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 19, 12121–12140,Short summary
Shipborne measurements of nitryl chloride (ClNO2) were made during the AQABA (Air Quality and climate change in the Arabian BAsin) ship campaign in summer 2017. The dataset includes measurements over the Mediterranean Sea and around the Arabian Peninsula with observed mixing ratios ranging from the limit of detection to 600 pptv. We examined the regional variability in the generation of ClNO2 and its importance for Cl atom generation in a marine boundary layer influenced by ships and industry.
Horst Fischer, Raoul Axinte, Heiko Bozem, John N. Crowley, Cheryl Ernest, Stefan Gilge, Sascha Hafermann, Hartwig Harder, Korbinian Hens, Ruud H. H. Janssen, Rainer Königstedt, Dagmar Kubistin, Chinmay Mallik, Monica Martinez, Anna Novelli, Uwe Parchatka, Christian Plass-Dülmer, Andrea Pozzer, Eric Regelin, Andreas Reiffs, Torsten Schmidt, Jan Schuladen, and Jos Lelieveld
Atmos. Chem. Phys., 19, 11953–11968,Short summary
We use in situ observations of H2O2 to study the interplay between photochemistry, transport and deposition processes. The data were obtained during five ground-based field campaigns across Europe. A budget calculation indicates that the photochemical production rate was much larger than photochemical loss and that dry deposition is the dominant loss process. To reproduce the change in H2O2 mixing ratios after sunrise, a variable contribution of entrainment from the residual layer is required.
Michael Rolletter, Martin Kaminski, Ismail-Hakki Acir, Birger Bohn, Hans-Peter Dorn, Xin Li, Anna Lutz, Sascha Nehr, Franz Rohrer, Ralf Tillmann, Robert Wegener, Andreas Hofzumahaus, Astrid Kiendler-Scharr, Andreas Wahner, and Hendrik Fuchs
Atmos. Chem. Phys., 19, 11635–11649,Short summary
Here we present a study of the photooxidation of alpha-pinene, the most abundant monoterpene, by hydroxyl radicals (OH) conducted in the simulation chamber SAPHIR under low NOx and atmospheric alpha-pinene concentrations. Yields of the main degradation products acetone, formaldehyde, and pinonaldehyde were determined and the HOx (OH + HO2) radical budget was investigated. Measurements were used to test current atmospheric models and a theory-based mechanism.
Eva Y. Pfannerstill, Nijing Wang, Achim Edtbauer, Efstratios Bourtsoukidis, John N. Crowley, Dirk Dienhart, Philipp G. Eger, Lisa Ernle, Horst Fischer, Bettina Hottmann, Jean-Daniel Paris, Christof Stönner, Ivan Tadic, David Walter, Jos Lelieveld, and Jonathan Williams
Atmos. Chem. Phys., 19, 11501–11523,Short summary
The Arabian Peninsula is a global hot spot of ozone pollution. Our measurements, made on a ship in summer 2017, indicate underlying reasons. Despite being at sea, we observed ozone-forming reactive trace gases (measured as so-called total OH reactivity) comparable to highly populated urban regions in amount and composition. This is due to strong emissions from oil extraction and ship traffic. These emissions were quickly converted to ozone due to intense solar irradiation and high temperatures.
Krista Luoma, Aki Virkkula, Pasi Aalto, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 19, 11363–11382,Short summary
We present an over 10-year-long time series of aerosol optical properties (AOPs) measured at a rural boreal forest site. Knowledge of AOPs is needed in determining the direct effect of aerosol particles on climate. We observed decreasing trends in scattering and absorption and increasing trends in backscattering fraction and single-scattering albedo. Trends of single-scattering albedo and backscattering fraction increased the efficiency of aerosol particles to scatter radiation back into space.
Meng Wang, Ru-Jin Huang, Junji Cao, Wenting Dai, Jiamao Zhou, Chunshui Lin, Haiyan Ni, Jing Duan, Ting Wang, Yang Chen, Yongjie Li, Qi Chen, Imad El Haddad, and Thorsten Hoffmann
Atmos. Meas. Tech., 12, 4779–4789,Short summary
The analytical performances of SE-GC-MS and TD-GC-MS for the determination of n-alkanes, PAHs and hopanes were evaluated and compared. The two methods show a good agreement with a high correlation efficient (R2 > 0.98) and a slope close to unity. The concentrations of n-alkanes, PAHs and hopanes are found to be much higher in Beijing than those in Chengdu, Shanghai and Guangzhou, most likely due to emissions from coal combustion for wintertime heating in Beijing.
Simo Hakala, Mansour A. Alghamdi, Pauli Paasonen, Ville Vakkari, Mamdouh I. Khoder, Kimmo Neitola, Lubna Dada, Ahmad S. Abdelmaksoud, Hisham Al-Jeelani, Ibrahim I. Shabbaj, Fahd M. Almehmadi, Anu-Maija Sundström, Heikki Lihavainen, Veli-Matti Kerminen, Jenni Kontkanen, Markku Kulmala, Tareq Hussein, and Antti-Pekka Hyvärinen
Atmos. Chem. Phys., 19, 10537–10555,Short summary
Atmospheric aerosols have significant effects on human health and the climate. A large fraction of these aerosols originate from new particle formation, where atmospheric vapors form small nanosized particles that grow into larger sizes, thus becoming climatically relevant. We show that large amounts of fast-growing particles are formed frequently at a site located in western Saudi Arabia and that these particles are likely connected to strong nearby emissions from human activities.
Jonathan Liebmann, Nicolas Sobanski, Jan Schuladen, Einar Karu, Heidi Hellén, Hannele Hakola, Qiaozhi Zha, Mikael Ehn, Matthieu Riva, Liine Heikkinen, Jonathan Williams, Horst Fischer, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 19, 10391–10403,Short summary
The formation of alkyl nitrates in the boreal forest was dominated by reactions of the NO3 radical with terpenes, both during the day and the night, with fewer contributions from OH and ozone. The alkyl nitrates formed had lifetimes on the order of 2 h, reflecting efficient loss via uptake to aerosol and deposition.
Christopher Pöhlker, David Walter, Hauke Paulsen, Tobias Könemann, Emilio Rodríguez-Caballero, Daniel Moran-Zuloaga, Joel Brito, Samara Carbone, Céline Degrendele, Viviane R. Després, Florian Ditas, Bruna A. Holanda, Johannes W. Kaiser, Gerhard Lammel, Jošt V. Lavrič, Jing Ming, Daniel Pickersgill, Mira L. Pöhlker, Maria Praß, Nina Löbs, Jorge Saturno, Matthias Sörgel, Qiaoqiao Wang, Bettina Weber, Stefan Wolff, Paulo Artaxo, Ulrich Pöschl, and Meinrat O. Andreae
Atmos. Chem. Phys., 19, 8425–8470,Short summary
The Amazon Tall Tower Observatory (ATTO) has been established to monitor the rain forest's biosphere–atmosphere exchange, which experiences the combined pressures from human-made deforestation and progressing climate change. This work is meant to be a reference study, which characterizes various geospatial properties of the ATTO footprint region and shows how the human-made transformation of Amazonia may impact future atmospheric observations at ATTO.
José Dias Neto, Stefan Kneifel, Davide Ori, Silke Trömel, Jan Handwerker, Birger Bohn, Normen Hermes, Kai Mühlbauer, Martin Lenefer, and Clemens Simmer
Earth Syst. Sci. Data, 11, 845–863,Short summary
This study describes a 2-month dataset of ground-based, vertically pointing triple-frequency cloud radar observations recorded during the winter season 2015/2016 in Jülich, Germany. Intensive quality control has been applied to the unique long-term dataset, which allows the multifrequency signatures of ice and snow particles to be statistically analyzed for the first time. The analysis includes, for example, aggregation and its dependence on cloud temperature, riming, and onset of melting.
Inken Heidke, Denis Scholz, and Thorsten Hoffmann
Clim. Past, 15, 1025–1037,Short summary
This is the first quantitative study of lignin biomarkers in stalagmites and cave drip water. Lignin is only produced by higher plants; therefore, its analysis can be used to reconstruct the vegetation of the past. We compared our lignin results with stable isotope and trace element records from the same samples and found correlations or similarities with P, Ba, U and Mg concentrations as well as δ13C values. These results can help to better interpret other vegetation proxies.
Zhaofeng Tan, Keding Lu, Andreas Hofzumahaus, Hendrik Fuchs, Birger Bohn, Frank Holland, Yuhan Liu, Franz Rohrer, Min Shao, Kang Sun, Yusheng Wu, Limin Zeng, Yinsong Zhang, Qi Zou, Astrid Kiendler-Scharr, Andreas Wahner, and Yuanhang Zhang
Atmos. Chem. Phys., 19, 7129–7150,Short summary
Atmospheric OH, HO2, and RO2 radicals; OH reactivity; and trace gases measured in the Pearl River Delta in autumn 2014 are used for radical budget analyses. The RO2 budget suggests that unexplained OH reactivity is due to unmeasured volatile organic compounds. The OH budget points to a missing OH source and that of RO2 to a missing RO2 sink at low NO. This could indicate a common, unknown process that converts RO2 to OH without the involvement of NO, which would reduce ozone production by 30 %.
Efstratios Bourtsoukidis, Lisa Ernle, John N. Crowley, Jos Lelieveld, Jean-Daniel Paris, Andrea Pozzer, David Walter, and Jonathan Williams
Atmos. Chem. Phys., 19, 7209–7232,Short summary
We report on results that demonstrate the utility of non-methane hydrocarbons as source/sink identification tracers while providing their mixing ratios around the Arabian Peninsula. By introducing novel data-analysis approaches, we establish a new method for separating associated and non-associated (with liquids) gases. We formulate a relationship between hydrocarbon oxidative pairs that can be used to evaluate the relative abundance of the hydroxyl and chlorine radicals in the troposphere.
Ralph Dlugi, Martina Berger, Chinmay Mallik, Anywhere Tsokankunku, Michael Zelger, Otávio C. Acevedo, Efstratios Bourtsoukidis, Andreas Hofzumahaus, Jürgen Kesselmeier, Gerhard Kramm, Daniel Marno, Monica Martinez, Anke C. Nölscher, Huug Ouwersloot, Eva Y. Pfannerstill, Franz Rohrer, Sebastian Tauer, Jonathan Williams, Ana-Maria Yáñez-Serrano, Meinrat O. Andreae, Hartwig Harder, and Matthias Sörgel
Atmos. Chem. Phys. Discuss.,
Publication in ACP not foreseenShort summary
Incomplete mixing (segregation) results in reduced chemical reaction rates compared to those expected from mean values and rate constants. Segregation has been suggested to cause discrepancies between modelled and measured OH radical concentrations. In this work, we summarize the intensities of segregation for the reaction of OH and isoprene for different field and modelling studies and compare those to our results from measurements in a pristine environment.
Kaspar R. Daellenbach, Ivan Kourtchev, Alexander L. Vogel, Emily A. Bruns, Jianhui Jiang, Tuukka Petäjä, Jean-Luc Jaffrezo, Sebnem Aksoyoglu, Markus Kalberer, Urs Baltensperger, Imad El Haddad, and André S. H. Prévôt
Atmos. Chem. Phys., 19, 5973–5991,Short summary
Here we present the molecular composition of the organic aerosol (OA) at an urban site in Central Europe (Zurich, Switzerland) and compare it to smog chamber wood smoke and ambient biogenic secondary OA (SOA) (Orbitrap analyses). Accordingly, we are able to explain the strong seasonality of the molecular composition by aged wood smoke and biogenic SOA during winter and summer. Our results could also explain the predominance of non-fossil organic carbon at European locations throughout the year.
Yonghong Wang, Yuesi Wang, Lili Wang, Tuukka Petäjä, Qiaozhi Zha, Chongshui Gong, Sixuan Li, Yuepeng Pan, Bo Hu, Jinyuan Xin, and Markku Kulmala
Atmos. Chem. Phys., 19, 5881–5888,Short summary
Satellite observations combined with in situ measurements demonstrate that increased inorganic aerosol fractions of NO2 and SO2 contribute to air pollution and frequently occurring haze in China from 1980 to 2010. Currently, the reduction of nitrate, sulfate and their precursor gases would contribute towards better visibility in China.
Rolf Sander, Andreas Baumgaertner, David Cabrera-Perez, Franziska Frank, Sergey Gromov, Jens-Uwe Grooß, Hartwig Harder, Vincent Huijnen, Patrick Jöckel, Vlassis A. Karydis, Kyle E. Niemeyer, Andrea Pozzer, Hella Riede, Martin G. Schultz, Domenico Taraborrelli, and Sebastian Tauer
Geosci. Model Dev., 12, 1365–1385,Short summary
We present the atmospheric chemistry box model CAABA/MECCA which now includes a number of new features: skeletal mechanism reduction, the MOM chemical mechanism for volatile organic compounds, an option to include reactions from the Master Chemical Mechanism (MCM) and other chemical mechanisms, updated isotope tagging, improved and new photolysis modules, and the new feature of coexisting multiple chemistry mechanisms. CAABA/MECCA is a community model published under the GPL.
Katri Leino, Janne Lampilahti, Pyry Poutanen, Riikka Väänänen, Antti Manninen, Stephany Buenrostro Mazon, Lubna Dada, Anna Franck, Daniela Wimmer, Pasi P. Aalto, Lauri R. Ahonen, Joonas Enroth, Juha Kangasluoma, Petri Keronen, Frans Korhonen, Heikki Laakso, Teemu Matilainen, Erkki Siivola, Hanna E. Manninen, Katrianne Lehtipalo, Veli-Matti Kerminen, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 19, 4127–4138,Short summary
This study presents airborne observations of particles, starting from 1.5 nm in diameter, above the boreal forest from 100 m up to 2700 m. The aim was to study the extent of NPF and likely places for nucleation. We found that the highest concentrations of 1.5–3 nm particles were above the forest canopy top on NPF event mornings, and the concentration decreased with increasing altitude. This would indicate the importance of gaseous precursors from vegetation for NPF processes in this area.
Mikko Äijälä, Kaspar R. Daellenbach, Francesco Canonaco, Liine Heikkinen, Heikki Junninen, Tuukka Petäjä, Markku Kulmala, André S. H. Prévôt, and Mikael Ehn
Atmos. Chem. Phys., 19, 3645–3672,Short summary
Aerosol mass spectrometry produces large amounts of complex data, the analysis of which necessitates chemometrics – the application of advanced statistical and mathematical tools to chemical data. Here, we perform a data-driven analysis of multiple aerosol mass spectrometric data sets, to show that the traditional separation of organics and inorganics is not necessary. The resulting 7-component aerosol speciation explains 83 % to 96 % of observed variability at our boreal forest experiment site.
Umar Javed, Dagmar Kubistin, Monica Martinez, Jan Pollmann, Markus Rudolf, Uwe Parchatka, Andreas Reiffs, Jim Thieser, Gerhard Schuster, Martin Horbanski, Denis Pöhler, John N. Crowley, Horst Fischer, Jos Lelieveld, and Hartwig Harder
Atmos. Meas. Tech., 12, 1461–1481,Short summary
Nitrogen dioxide (NO2) affects the concentration of key species like ozone, hydroxyl radical, and nitrate radical in the atmosphere. In situ, direct, and interference-free NO2 measurements are important for validating our understanding of NOx chemistry related to ozone formation and the radical loss process. This article describes the important features and performance of a newly developed NO2 instrument during a field intercomparison.
Nikos Kalivitis, Veli-Matti Kerminen, Giorgos Kouvarakis, Iasonas Stavroulas, Evaggelia Tzitzikalaki, Panayiotis Kalkavouras, Nikos Daskalakis, Stelios Myriokefalitakis, Aikaterini Bougiatioti, Hanna E. Manninen, Pontus Roldin, Tuukka Petäjä, Michael Boy, Markku Kulmala, Maria Kanakidou, and Nikolaos Mihalopoulos
Atmos. Chem. Phys., 19, 2671–2686,Short summary
New particle formation (NPF) is an important source of atmospheric aerosols. For the Mediterranean atmosphere, only few studies exist. In this study we present one of the longest series of NPF by analyzing 10 years of data from Crete, Greece. NPF took place on 27 % of the available days; it was more frequent in spring and less so in late summer. Model simulations showed that NPF in the subtropical environment may differ greatly from that in the boreal environment.
Guo Li, Yafang Cheng, Uwe Kuhn, Rongjuan Xu, Yudong Yang, Hannah Meusel, Zhibin Wang, Nan Ma, Yusheng Wu, Meng Li, Jonathan Williams, Thorsten Hoffmann, Markus Ammann, Ulrich Pöschl, Min Shao, and Hang Su
Atmos. Chem. Phys., 19, 2209–2232,Short summary
VOCs play a key role in atmospheric chemistry. Emission and deposition on soil have been suggested as important sources and sinks of atmospheric trace gases. The exchange characteristics and heterogeneous chemistry of VOCs on soil, however, are not well understood. We used a newly designed differential coated-wall flow tube system to investigate the long-term variability of bidirectional air–soil exchange of 13 VOCs at ambient air conditions of an urban background site in Beijing.
Michael Boy, Erik S. Thomson, Juan-C. Acosta Navarro, Olafur Arnalds, Ekaterina Batchvarova, Jaana Bäck, Frank Berninger, Merete Bilde, Zoé Brasseur, Pavla Dagsson-Waldhauserova, Dimitri Castarède, Maryam Dalirian, Gerrit de Leeuw, Monika Dragosics, Ella-Maria Duplissy, Jonathan Duplissy, Annica M. L. Ekman, Keyan Fang, Jean-Charles Gallet, Marianne Glasius, Sven-Erik Gryning, Henrik Grythe, Hans-Christen Hansson, Margareta Hansson, Elisabeth Isaksson, Trond Iversen, Ingibjorg Jonsdottir, Ville Kasurinen, Alf Kirkevåg, Atte Korhola, Radovan Krejci, Jon Egill Kristjansson, Hanna K. Lappalainen, Antti Lauri, Matti Leppäranta, Heikki Lihavainen, Risto Makkonen, Andreas Massling, Outi Meinander, E. Douglas Nilsson, Haraldur Olafsson, Jan B. C. Pettersson, Nønne L. Prisle, Ilona Riipinen, Pontus Roldin, Meri Ruppel, Matthew Salter, Maria Sand, Øyvind Seland, Heikki Seppä, Henrik Skov, Joana Soares, Andreas Stohl, Johan Ström, Jonas Svensson, Erik Swietlicki, Ksenia Tabakova, Throstur Thorsteinsson, Aki Virkkula, Gesa A. Weyhenmeyer, Yusheng Wu, Paul Zieger, and Markku Kulmala
Atmos. Chem. Phys., 19, 2015–2061,Short summary
The Nordic Centre of Excellence CRAICC (Cryosphere–Atmosphere Interactions in a Changing Arctic Climate), funded by NordForsk in the years 2011–2016, is the largest joint Nordic research and innovation initiative to date and aimed to strengthen research and innovation regarding climate change issues in the Nordic region. The paper presents an overview of the main scientific topics investigated and provides a state-of-the-art comprehensive summary of what has been achieved in CRAICC.
Timo Vihma, Petteri Uotila, Stein Sandven, Dmitry Pozdnyakov, Alexander Makshtas, Alexander Pelyasov, Roberta Pirazzini, Finn Danielsen, Sergey Chalov, Hanna K. Lappalainen, Vladimir Ivanov, Ivan Frolov, Anna Albin, Bin Cheng, Sergey Dobrolyubov, Viktor Arkhipkin, Stanislav Myslenkov, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 19, 1941–1970,Short summary
The Arctic marine climate system, ecosystems, and socio-economic systems are changing rapidly. This calls for the establishment of a marine Arctic component of the Pan-Eurasian Experiment (MA-PEEX), for which we present a plan. The program will promote international collaboration; sustainable marine meteorological, sea ice, and oceanographic observations; advanced data management; and multidisciplinary research on the marine Arctic and its interaction with the Eurasian continent.
Laura Tomsche, Andrea Pozzer, Narendra Ojha, Uwe Parchatka, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 19, 1915–1939,Short summary
The Asian monsoon anticyclone (AMA) is an annual phenomenon in the northern hemispheric upper troposphere (UT) and lower stratosphere. We performed in situ measurements of carbon monoxide (CO) and methane (CH4) in the monsoon outflow region and in background air in the UT (Mediterranean, Arabian Peninsula, Arabian Sea) using airborne optical absorption spectroscopy during the Oxidation Mechanism Observations mission (summer 2015). The trace gases increased within the AMA, particularly CH4.
Yiqun Lu, Chao Yan, Yueyun Fu, Yan Chen, Yiliang Liu, Gan Yang, Yuwei Wang, Federico Bianchi, Biwu Chu, Ying Zhou, Rujing Yin, Rima Baalbaki, Olga Garmash, Chenjuan Deng, Weigang Wang, Yongchun Liu, Tuukka Petäjä, Veli-Matti Kerminen, Jingkun Jiang, Markku Kulmala, and Lin Wang
Atmos. Chem. Phys., 19, 1971–1983,Short summary
Gaseous sulfuric acid is one of the key precursors for atmospheric new particle formation processes, but its measurement remains challenging. This work develops an estimation method for the gaseous sulfuric acid concentration in an urban environment in China using multiple atmospheric variables that are easier to measure. The consideration of the heterogeneous formation of HONO and the subsequent photo-production of OH radicals improves the performance of the estimation method.
Sascha R. Albrecht, Anna Novelli, Andreas Hofzumahaus, Sungah Kang, Yare Baker, Thomas Mentel, Andreas Wahner, and Hendrik Fuchs
Atmos. Meas. Tech., 12, 891–902,Short summary
Within this study we demonstrate reliable measurement of hydroperoxy (HO2) radicals via chemical ionisation mass spectrometry. HO2 is detected as an ion cluster with bromide ions, which allows a selective detection. This direct and sensitive measurement provides reliable data of HO2 radical concentrations in the atmosphere as demonstrated in the first application in simulation chamber experiments.
Maik Renner, Claire Brenner, Kaniska Mallick, Hans-Dieter Wizemann, Luigi Conte, Ivonne Trebs, Jianhui Wei, Volker Wulfmeyer, Karsten Schulz, and Axel Kleidon
Hydrol. Earth Syst. Sci., 23, 515–535,Short summary
We estimate the phase lag of surface states and heat fluxes to incoming solar radiation at the sub-daily timescale. While evapotranspiration reveals a minor phase lag, the vapor pressure deficit used as input by Penman–Monteith approaches shows a large phase lag. The surface-to-air temperature gradient used by energy balance residual approaches shows a small phase shift in agreement with the sensible heat flux and thus explains the better correlation of these models at the sub-daily timescale.
Biwu Chu, Veli-Matti Kerminen, Federico Bianchi, Chao Yan, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 19, 115–138,Short summary
The characteristics of new particle formation (NPF) in China, including frequency, formation rate, and particle growth rate, were summarized comprehensively and were compared among observations in different environments. The interactions between air pollution and NPF are discussed, as well as the possible reasons for more frequent NPF under heavy pollution conditions than in our current understanding. Significant and future research directions for NPF studies in China are also summarized.
Fidel Pankratov, Alexander Mahura, Tuukka Petäjä, Valentin Popov, and Vladimir Masloboev
Atmos. Chem. Phys. Discuss.,
Revised manuscript not acceptedShort summary
Analysis of long-term observations for atmospheric mercury in the Russian Arctic, considering inter-annual, seasonal and monthly variabilities is in focus. Linkage of elevated concentrations with volcanic eruptions in Iceland is explored. Results showed that active volcanoes can play a role of sources for increased mercury levels in the Northern Hemisphere due to long-range atmospheric transport of volcanic clouds towards the Arctic.
Lubna Dada, Robert Chellapermal, Stephany Buenrostro Mazon, Pauli Paasonen, Janne Lampilahti, Hanna E. Manninen, Heikki Junninen, Tuukka Petäjä, Veli-Matti Kerminen, and Markku Kulmala
Atmos. Chem. Phys., 18, 17883–17893,Short summary
Our paper provides an automatic method to classify new particle formation events into four classes based on the accompanying air ion concentrations. The method is applied to 10 years of data measured within the SMEAR II station and was capable of eliminating the undefined class as well as defining the start, peak and end times of a regional event by monitoring the initial steps of cluster formation. Our method can be modified and applied to different locations where particle formation occurs.
Ekaterina Ezhova, Ilona Ylivinkka, Joel Kuusk, Kaupo Komsaare, Marko Vana, Alisa Krasnova, Steffen Noe, Mikhail Arshinov, Boris Belan, Sung-Bin Park, Jošt Valentin Lavrič, Martin Heimann, Tuukka Petäjä, Timo Vesala, Ivan Mammarella, Pasi Kolari, Jaana Bäck, Üllar Rannik, Veli-Matti Kerminen, and Markku Kulmala
Atmos. Chem. Phys., 18, 17863–17881,Short summary
Understanding the connections between aerosols, solar radiation and photosynthesis in terrestrial ecosystems is important for estimates of the CO2 balance in the atmosphere. Atmospheric aerosols and clouds influence solar radiation. In this study, we quantify the aerosol effect on solar radiation in boreal forests and study forest ecosystems response to this change in the radiation conditions. The analysis is based on atmospheric observations from several remote stations in Eurasian forests.
Liqing Hao, Olga Garmash, Mikael Ehn, Pasi Miettinen, Paola Massoli, Santtu Mikkonen, Tuija Jokinen, Pontus Roldin, Pasi Aalto, Taina Yli-Juuti, Jorma Joutsensaari, Tuukka Petäjä, Markku Kulmala, Kari E. J. Lehtinen, Douglas R. Worsnop, and Annele Virtanen
Atmos. Chem. Phys., 18, 17705–17716,Short summary
An aerosol mass spectrometer was used to characterize aerosol chemical composition during new particle formation periods. The time profiles of mass concentrations and chemical composition of observed aerosol particles are subjected to joint effects of boundary layer dilution, atmospheric chemistry and aerosol mixing in different boundary layers. During the nighttime, the increase in organic aerosol mass correlated well with the increase in condensed highly oxygenated organic molecules' mass.
Qiaozhi Zha, Chao Yan, Heikki Junninen, Matthieu Riva, Nina Sarnela, Juho Aalto, Lauriane Quéléver, Simon Schallhart, Lubna Dada, Liine Heikkinen, Otso Peräkylä, Jun Zou, Clémence Rose, Yonghong Wang, Ivan Mammarella, Gabriel Katul, Timo Vesala, Douglas R. Worsnop, Markku Kulmala, Tuukka Petäjä, Federico Bianchi, and Mikael Ehn
Atmos. Chem. Phys., 18, 17437–17450,Short summary
Vertical measurements of highly oxygenated molecules (HOMs) below and above the forest canopy were performed for the first time in a boreal forest during September 2016. Our results highlight that near-ground HOM measurements may only be representative of a small fraction of the entire nocturnal boundary layer, which may sequentially influence the growth of newly formed particles and SOA formation close to ground surface, where the majority of measurements are conducted.
Robbie Ramsay, Chiara F. Di Marco, Mathew R. Heal, Marsailidh M. Twigg, Nicholas Cowan, Matthew R. Jones, Sarah R. Leeson, William J. Bloss, Louisa J. Kramer, Leigh Crilley, Matthias Sörgel, Meinrat Andreae, and Eiko Nemitz
Atmos. Chem. Phys., 18, 16953–16978,Short summary
Understanding the impact of agricultural activities on the atmosphere requires more measurements of inorganic trace gases and associated aerosol counterparts. This research presents 1 month of measurements above agricultural grassland during a period of fertiliser application. It was found that emissions of the important trace gases ammonia and nitrous acid peaked after fertiliser use and that the velocity at which the measured aerosols were deposited was dependent upon their size.
Cristina Carnerero, Noemí Pérez, Cristina Reche, Marina Ealo, Gloria Titos, Hong-Ku Lee, Hee-Ram Eun, Yong-Hee Park, Lubna Dada, Pauli Paasonen, Veli-Matti Kerminen, Enrique Mantilla, Miguel Escudero, Francisco J. Gómez-Moreno, Elisabeth Alonso-Blanco, Esther Coz, Alfonso Saiz-Lopez, Brice Temime-Roussel, Nicolas Marchand, David C. S. Beddows, Roy M. Harrison, Tuukka Petäjä, Markku Kulmala, Kang-Ho Ahn, Andrés Alastuey, and Xavier Querol
Atmos. Chem. Phys., 18, 16601–16618,Short summary
The vertical distribution of new particle formation events was studied using tethered balloons carrying miniaturized instrumentation. Results show that new particle formation and growth occurs only in the lower layer of the atmosphere, where aerosols are mixed due to convection, especially when the atmosphere is clean. A comparison of urban and suburban surface stations was also made, suggesting that such events may have a significant impact on ultrafine particle concentrations in a wide area.
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,Short summary
Atmospheric aerosols have diverse effects on air quality, human health, and global climate. One important source of aerosols is their formation via nucleation and growth in the atmosphere. We have analyzed long-term observations of regional new particle formation events around the globe and provide a comprehensive view on the characteristics of this phenomenon in diverse environments. The results are useful in developing more realistic representation of atmospheric aerosols in global models.
Juan Hong, Hanbing Xu, Haobo Tan, Changqing Yin, Liqing Hao, Fei Li, Mingfu Cai, Xuejiao Deng, Nan Wang, Hang Su, Yafang Cheng, Lin Wang, Tuukka Petäjä, and Veli-Matti Kerminen
Atmos. Chem. Phys., 18, 14079–14094,Short summary
In this manuscript, we provide the results of the hygroscopicity of a more anthropogenically influenced aerosol in a suburban site in China. Organic material in the current type of aerosols showed moderate hygroscopicity, and it appeared to be less sensitive towards the variation of its oxidation level, which suggests different characteristics of the oxidation products in secondary organic aerosols (SOA) under the suburban/urban atmosphere in China when compared to other background environments.
Inken Heidke, Denis Scholz, and Thorsten Hoffmann
Biogeosciences, 15, 5831–5845,Short summary
We developed a sensitive method to analyze the lignin composition of organic traces contained in speleothems. Lignin is a main constituent of woody plants and its composition contains information about the type of vegetation. This method offers new possibilities to reconstruct the vegetation of past millennia since it combines the advantages of lignin analysis as a highly specific vegetation biomarker with the benefits of speleothems as unique terrestrial climate archives.
Heidi Hellén, Arnaud P. Praplan, Toni Tykkä, Ilona Ylivinkka, Ville Vakkari, Jaana Bäck, Tuukka Petäjä, Markku Kulmala, and Hannele Hakola
Atmos. Chem. Phys., 18, 13839–13863,Short summary
Exceptionally large ambient air concentration datasets of VOCs were measured in a boreal forest. For the first time concentration of the main sesquiterpene (β-caryophyllene) emitted by the local trees was also measured. Sesquiterpenes were found to have a major impact on local atmospheric chemistry, even though their concentrations were 30 times lower than the monoterpene concentrations. In addition, sesquiterpenes are expected to have a high impact on local secondary organic aerosol production.
John N. Crowley, Nicolas Pouvesle, Gavin J. Phillips, Raoul Axinte, Horst Fischer, Tuukka Petäjä, Anke Nölscher, Jonathan Williams, Korbinian Hens, Hartwig Harder, Monica Martinez-Harder, Anna Novelli, Dagmar Kubistin, Birger Bohn, and Jos Lelieveld
Atmos. Chem. Phys., 18, 13457–13479,Short summary
Simultaneous observations of PAA, PAN and H2O2 are used to provide insight into processes influencing the HOx chemistry of the boreal forest, including two biomass-burning-impacted periods. A significant contribution from photolytic HOx sources was included in a box model analysis to align model predictions with measurements. The model predicts high levels of organic peroxy radicals, also at night-time.
Pertti Hari, Steffen Noe, Sigrid Dengel, Jan Elbers, Bert Gielen, Veli-Matti Kerminen, Bart Kruijt, Liisa Kulmala, Anders Lindroth, Ivan Mammarella, Tuukka Petäjä, Guy Schurgers, Anni Vanhatalo, Markku Kulmala, and Jaana Bäck
Atmos. Chem. Phys., 18, 13321–13328,Short summary
The development of eddy-covariance measurements of ecosystem CO2 fluxes began a new era in the field studies of photosynthesis. The interpretation of the very variable CO2 fluxes in evergreen forests has been problematic especially in seasonal transition times. We apply two theoretical needle-level equations and show they can predict photosynthetic CO2 flux between the atmosphere and Scots pine forests. This has strong implications for the interpretation of the global change and boreal forests.
Daniela Wimmer, Stephany Buenrostro Mazon, Hanna Elina Manninen, Juha Kangasluoma, Alessandro Franchin, Tuomo Nieminen, John Backman, Jian Wang, Chongai Kuang, Radovan Krejci, Joel Brito, Fernando Goncalves Morais, Scot Turnbull Martin, Paulo Artaxo, Markku Kulmala, Veli-Matti Kerminen, and Tuukka Petäjä
Atmos. Chem. Phys., 18, 13245–13264,Short summary
This work focuses on understanding the production of very small airborne particles in the undisturbed environment of the Amazon basin. Computer models have shown that up to 70 % of these tiny particles are responsible for cloud formation on a global scale. The processes behind the production of these very small particles have been studied intensely recently. Their appearance has been observed almost all over the world. We directly measure sub-3 nm aerosols for the first time in the Amazon basin.
Chao Yan, Lubna Dada, Clémence Rose, Tuija Jokinen, Wei Nie, Siegfried Schobesberger, Heikki Junninen, Katrianne Lehtipalo, Nina Sarnela, Ulla Makkonen, Olga Garmash, Yonghong Wang, Qiaozhi Zha, Pauli Paasonen, Federico Bianchi, Mikko Sipilä, Mikael Ehn, Tuukka Petäjä, Veli-Matti Kerminen, Douglas R. Worsnop, and Markku Kulmala
Atmos. Chem. Phys., 18, 13231–13243,Short summary
Ions can play an important role in atmospheric new particle formation by stabilizing the embryonic clusters. Such a process is called ion-induced nucleation (IIN). We found two distinct IIN mechanisms – driven by H2SO4-NH3 clusters and by organic vapors, respectively. The concentration ratio of organic vapors to H2SO4 regulates via which pathway the IIN occur. As the organic vapor concentration is influenced by temperature, a seasonal variation in the main IIN mechanism can be expected.
Jorge Saturno, Bruna A. Holanda, Christopher Pöhlker, Florian Ditas, Qiaoqiao Wang, Daniel Moran-Zuloaga, Joel Brito, Samara Carbone, Yafang Cheng, Xuguang Chi, Jeannine Ditas, Thorsten Hoffmann, Isabella Hrabe de Angelis, Tobias Könemann, Jošt V. Lavrič, Nan Ma, Jing Ming, Hauke Paulsen, Mira L. Pöhlker, Luciana V. Rizzo, Patrick Schlag, Hang Su, David Walter, Stefan Wolff, Yuxuan Zhang, Paulo Artaxo, Ulrich Pöschl, and Meinrat O. Andreae
Atmos. Chem. Phys., 18, 12817–12843,Short summary
Biomass burning emits light-absorbing aerosol particles that warm the atmosphere. One of them is the primarily emitted black carbon, which strongly absorbs radiation in the visible and UV spectral regions. Another one is the so-called brown carbon, a fraction of organic aerosol particles that are able to absorb radiation, especially in the UV spectral region. The contribution of both kinds of aerosol particles to light absorption over the Amazon rainforest is studied in this paper.
Martha A. Zaidan, Ville Haapasilta, Rishi Relan, Pauli Paasonen, Veli-Matti Kerminen, Heikki Junninen, Markku Kulmala, and Adam S. Foster
Atmos. Chem. Phys., 18, 12699–12714,Short summary
This article promotes the use of the mutual information method for finding any non-linear associations among atmospheric variables. We demonstrate that the same results from previous studies are obtained by this method, which operates without supervision and without the need of understanding the physics deeply. This suggests that the method is suitable to be implemented widely in the atmospheric field to discover other interesting phenomena and their relevant variables.
Zhaofeng Tan, Franz Rohrer, Keding Lu, Xuefei Ma, Birger Bohn, Sebastian Broch, Huabin Dong, Hendrik Fuchs, Georgios I. Gkatzelis, Andreas Hofzumahaus, Frank Holland, Xin Li, Ying Liu, Yuhan Liu, Anna Novelli, Min Shao, Haichao Wang, Yusheng Wu, Limin Zeng, Min Hu, Astrid Kiendler-Scharr, Andreas Wahner, and Yuanhang Zhang
Atmos. Chem. Phys., 18, 12391–12411,Short summary
We present the first wintertime OH, HO2, and RO2 measurements in Beijing, China. OH concentrations are nearly 2-fold larger than those observed in foreign cities during wintertime. The high OH and large OH reactivities indicate photochemical processes can be effective even during wintertime. A box model largely underestimated HO2 and RO2 concentrations during pollution episodes correlated with high NOx, indicating a deficit current chemistry in the high NOx regime.
Anni Vanhatalo, Andrea Ghirardo, Eija Juurola, Jörg-Peter Schnitzler, Ina Zimmer, Heidi Hellén, Hannele Hakola, and Jaana Bäck
Biogeosciences, 15, 5047–