Articles | Volume 3, issue 2
https://doi.org/10.5194/ar-3-589-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/ar-3-589-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
28 Nov 2025
Research article |
| 28 Nov 2025
| 28 Nov 2025
Global fields of daily accumulation-mode particle number concentrations using in situ observations, reanalysis data, and machine learning
Institute for Atmospheric and Earth System Research (INAR)/Physics, University of Helsinki, Helsinki, Finland
Elio Rauth
Department of Computer Science, University of Helsinki, Helsinki, Finland
Department of Remote Sensing, Institute of Geography and Geology, University of Würzburg, Würzburg, Germany
Daniel Holmberg
Department of Computer Science, University of Helsinki, Helsinki, Finland
Paulo Artaxo
Institute of Physics, University of São Paulo, São Paulo, Brazil
John Backman
Finnish Meteorological Institute (FMI), Erik Palménin aukio 1, 00560, Helsinki, Finland
Benjamin Bergmans
Institut Scientifique de Service Public (ISSeP), Liege, Belgium
Don Collins
University of California, Riverside, USA
Marco Aurélio Franco
Institute of Astronomy, Geophysics and Atmospheric Sciences, University of São Paulo, São Paulo, Brazil
Shahzad Gani
Institute for Atmospheric and Earth System Research (INAR)/Physics, University of Helsinki, Helsinki, Finland
Centre for Atmospheric Sciences, Indian Institute of Technology Delhi, New Delhi, India
Roy M. Harrison
School of Geography, Earth & Environmental Sciences, University of Birmingham, Birmingham, United Kingdom
Rakesh K. Hooda
Finnish Meteorological Institute (FMI), Erik Palménin aukio 1, 00560, Helsinki, Finland
Tareq Hussein
Institute for Atmospheric and Earth System Research (INAR)/Physics, University of Helsinki, Helsinki, Finland
University of Jordan, School of Science, Department of Physics, Environmental and Atmospheric Research Laboratory (EARL), Amman, 11942, Jordan
Antti-Pekka Hyvärinen
Finnish Meteorological Institute (FMI), Erik Palménin aukio 1, 00560, Helsinki, Finland
Kerneels Jaars
Atmospheric Chemistry Research Group, Chemical Resource Beneficiation, North-West University, Potchefstroom, South Africa
Adam Kristensson
Department of Physics, Lund University, Lund, Sweden
Markku Kulmala
Institute for Atmospheric and Earth System Research (INAR)/Physics, University of Helsinki, Helsinki, Finland
Aerosol and Haze Laboratory, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China
Nanjing-Helsinki Institute in Atmospheric and Earth System Sciences, Nanjing University, Nanjing, China
School of Atmospheric Sciences, Nanjing University, Nanjing, China
Lauri Laakso
Finnish Meteorological Institute (FMI), Erik Palménin aukio 1, 00560, Helsinki, Finland
Atmospheric Chemistry Research Group, Chemical Resource Beneficiation, North-West University, Potchefstroom, South Africa
Ari Laaksonen
Finnish Meteorological Institute (FMI), Erik Palménin aukio 1, 00560, Helsinki, Finland
Department of Technical Physics, University of Eastern Finland, Kuopio, Finland
Nikolaos Mihalopoulos
Department of Chemistry, University of Crete, Heraklion, Greece
Institute for Environmental Research and Sustainable Development, National Observatory of Athens, Palaia Penteli, 15236 Athens, Greece
Colin O'Dowd
School of Physics, National University of Ireland, Galway, Ireland
Jakub Ondracek
Research Group of Aerosol Chemistry and Physics, Institute of Chemical Process Fundamentals of the CAS, Prague, Czech Republic
Tuukka Petäjä
Institute for Atmospheric and Earth System Research (INAR)/Physics, University of Helsinki, Helsinki, Finland
Kristina Plauškaitė
Center for Physical Sciences and Technology (FTMC), Vilnius, Lithuania
Mira Pöhlker
Leibniz Institute for Tropospheric Research (TROPOS), Leipzig, Germany
Ximeng Qi
Nanjing-Helsinki Institute in Atmospheric and Earth System Sciences, Nanjing University, Nanjing, China
School of Atmospheric Sciences, Nanjing University, Nanjing, China
Peter Tunved
Department of Environmental Science, Stockholm University, Stockholm, Sweden
Ville Vakkari
Finnish Meteorological Institute (FMI), Erik Palménin aukio 1, 00560, Helsinki, Finland
Atmospheric Chemistry Research Group, Chemical Resource Beneficiation, North-West University, Potchefstroom, South Africa
Alfred Wiedensohler
Leibniz Institute for Tropospheric Research (TROPOS), Leipzig, Germany
Kai Puolamäki
Institute for Atmospheric and Earth System Research (INAR)/Physics, University of Helsinki, Helsinki, Finland
Department of Computer Science, University of Helsinki, Helsinki, Finland
Tuomo Nieminen
Institute for Atmospheric and Earth System Research (INAR)/Physics, University of Helsinki, Helsinki, Finland
Department of Physics, University of Helsinki, Helsinki, Finland
Veli-Matti Kerminen
Institute for Atmospheric and Earth System Research (INAR)/Physics, University of Helsinki, Helsinki, Finland
Victoria A. Sinclair
Institute for Atmospheric and Earth System Research (INAR)/Physics, University of Helsinki, Helsinki, Finland
Pauli Paasonen
CORRESPONDING AUTHOR
Institute for Atmospheric and Earth System Research (INAR)/Physics, University of Helsinki, Helsinki, Finland
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Alexandra P. Tsimpidi, Susanne M. C. Scholz, Alexandros Milousis, Nikolaos Mihalopoulos, and Vlassis A. Karydis
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This study examines global changes in air pollution from 2000 to 2020, focusing on fine aerosols that impact climate and health. Using models and global data, it finds that organic aerosols dominate in many regions, especially with wildfires or natural emissions. Pollution from sulfate and nitrate has decreased in Europe and North America due to regulations, while trends in Asia are more complex. The findings improve understanding and support policies for cleaner air and healthier environments.
Tinghan Zhang, Ximeng Qi, Janne Lampilahti, Liangduo Chen, Xuguang Chi, Wei Nie, Xin Huang, Zehao Zou, Wei Du, Tom Kokkonen, Tuukka Petäjä, Katrianne Lehtipalo, Veli-Matti Kerminen, Aijun Ding, and Markku Kulmala
Atmos. Chem. Phys., 25, 10027–10048, https://doi.org/10.5194/acp-25-10027-2025, https://doi.org/10.5194/acp-25-10027-2025, 2025
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By comparing air ions at two flagship sites – a boreal forest site in Finland and a megacity site in eastern China – we characterized ion concentrations and their roles in new particle formation (NPF) across contrasting environments. The ion-induced fraction was much higher in the clean boreal forest. However, earlier activation of charged particles and high ion-induced fraction during quiet NPF in the megacity site imply a non-negligible role for ion-induced NPF in polluted urban areas.
Simone Pulimeno, Angelo Lupi, Vito Vitale, Claudia Frangipani, Carlos Toledano, Stelios Kazadzis, Natalia Kouremeti, Christoph Ritter, Sandra Graßl, Kerstin Stebel, Vitali Fioletov, Ihab Abboud, Sandra Blindheim, Lynn Ma, Norm O’Neill, Piotr Sobolewski, Pawan Gupta, Elena Lind, Thomas F. Eck, Antti Hyvärinen, Veijo Aaltonen, Rigel Kivi, Janae Csavina, Dmitry Kabanov, Sergey M. Sakerin, Olga R. Sidorova, Robert S. Stone, Hagen Telg, Laura Riihimaki, Raul R. Cordero, Martin Radenz, Ronny Engelmann, Michel Van Roozendal, Anatoli Chaikovsky, Philippe Goloub, Junji Hisamitsu, and Mauro Mazzola
EGUsphere, https://doi.org/10.5194/egusphere-2025-2527, https://doi.org/10.5194/egusphere-2025-2527, 2025
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This study analyzed aerosols optical properties over the Arctic and Antarctic to measure them even during long periods of darkness. It found that pollution in the Arctic is decreasing, likely due to European emission regulations, while wildfires are becoming a more important source of particles. In Antarctica, particle levels are higher near the coast than inland, and vary by season. These results help us better understand how air pollution and climate are changing at the Earth’s poles.
Martina Mazzini, Diego Aliaga, Janne Lamphilati, Martin Gysel-Beer, Benjamin Tobias Brem, Robin Lewis Modini, Dominic Heslin-Rees, Tareq Hussein, Marco Zanatta, Paolo Cristofanelli, Federico Bianchi, Markku Kulmala, and Angela Marinoni
EGUsphere, https://doi.org/10.5194/egusphere-2025-3842, https://doi.org/10.5194/egusphere-2025-3842, 2025
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This study investigates particle number size distribution at two high mountain stations in Europe, aiming to clarify the mechanisms driving new particle formation (NPF) in the free troposphere. Interestingly, despite a consistently higher background of freshly nucleated particles at JFJ, NPF events were more frequent and intense at CMN. CMN also exhibited higher particle formation and growth rates, possibly linked to the proximity of the polluted planetary boundary layer from the Po Valley.
Lenka Suchánková, Jakub Ondráček, Naděžda Zíková, Petr Roztočil, Petr Vodička, Roman Prokeš, Ivan Holoubek, and Vladimir Ždímal
EGUsphere, https://doi.org/10.5194/egusphere-2025-3800, https://doi.org/10.5194/egusphere-2025-3800, 2025
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In this work, we show how aerosol particles in city air change their ability to scatter light when exposed to humidity, which affects the climate. Using a new, simpler tool, we found that in Prague's suburbs, these particles showed only a small change in light scattering, likely due to carbon-rich pollution that effectively absorbs light. Our method reduces measurement uncertainty and helps fill gaps in urban climate data.
Rafael Stern, Joel F. de Brito, Samara Carbone, Luciana Varanda Rizzo, Jonathan Daniel Muller, and Paulo Artaxo
Atmos. Chem. Phys., 25, 9451–9469, https://doi.org/10.5194/acp-25-9451-2025, https://doi.org/10.5194/acp-25-9451-2025, 2025
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Our work reveals the impact of forest fires on climate. We found that fire-related particles not only absorb sunlight and warm the atmosphere, but also scatter light, which cools it. At our remote Amazonia site, most particles had different chemical makeups than direct fire emissions and were the main drivers of how much sunlight was blocked or redirected.
Maija Peltola, Roseline Thakur, Kurt Spence, Janne Lampilahti, Ronja Mäkelä, Sasu Karttunen, Ekaterina Ezhova, Sami Haapanala, Aki Vähä, Juha Kangasluoma, Tommy Chan, Pauli Paasonen, Joanna Norkko, Alf Norkko, Markku Kulmala, and Mikael Ehn
EGUsphere, https://doi.org/10.5194/egusphere-2025-3809, https://doi.org/10.5194/egusphere-2025-3809, 2025
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Here we report aerosol properties from a new atmospheric observatory established at the Finnish Baltic Sea Coast. Aerosol formation was observed when air masses crossed over the continent whereas less newly formed particles were observed when the winds were from the sea. Aerosol formation was favoured by low condensation sink and sunny dry conditions.
Laura Rautiainen, Milla Johansson, Mikko Lensu, Jani Tyynelä, Jukka-Pekka Jalkanen, Ken Stenbäck, Harry Lonka, and Lauri Laakso
EGUsphere, https://doi.org/10.5194/egusphere-2025-1790, https://doi.org/10.5194/egusphere-2025-1790, 2025
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We present an experimental Automatic Identification System (AIS) receiver set-up to study anomalous signal propagation over coastal and marine waters in the northern Baltic Sea. Anomalous atmospheric conditions can allow for the AIS messages to be received from farther distances than under normal conditions. The results show that under anomalous conditions, the messages can be received up to 600 km away and have both diurnal and seasonal cycles.
Yifan Yang, Thomas Müller, Laurent Poulain, Samira Atabakhsh, Bruna A. Holanda, Jens Voigtländer, Shubhi Arora, and Mira L. Pöhlker
Atmos. Chem. Phys., 25, 8637–8655, https://doi.org/10.5194/acp-25-8637-2025, https://doi.org/10.5194/acp-25-8637-2025, 2025
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Black carbon (BC) is the major atmospheric aerosol that can absorb light and influence climate. We measured the physical properties of BC at a background site in Germany. In summer, BC particles were smaller and the mixture with other atmospheric components occurred during the daytime. In winter, emissions from residential heating significantly influenced BC's properties. Understanding these characteristics of BC can help to improve the accuracy of aerosol optic simulation.
Tuomas Naakka, Daniel Köhler, Kalle Nordling, Petri Räisänen, Marianne Tronstad Lund, Risto Makkonen, Joonas Merikanto, Bjørn H. Samset, Victoria A. Sinclair, Jennie L. Thomas, and Annica M. L. Ekman
Atmos. Chem. Phys., 25, 8127–8145, https://doi.org/10.5194/acp-25-8127-2025, https://doi.org/10.5194/acp-25-8127-2025, 2025
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The effects of warmer sea surface temperatures and decreasing sea ice cover on polar climates have been studied using four climate models with identical prescribed changes in sea surface temperatures and sea ice cover. The models predict similar changes in air temperature and precipitation in the polar regions in a warmer climate with less sea ice. However, the models disagree on how the atmospheric circulation, i.e. the large-scale winds, will change with warmer temperatures and less sea ice.
Myriam Agrò, Manuel Bettineschi, Silvia Melina, Diego Aliaga, Andrea Bergomi, Beatrice Biffi, Alessandro Bigi, Giancarlo Ciarelli, Cristina Colombi, Paola Fermo, Ivan Grigioni, Veli-Matti Kerminen, Markku Kulmala, Janne Lampilahti, Angela Marinoni, Celestine Oliewo, Juha Sulo, Gianluigi Valli, Roberta Vecchi, Tuukka Petäjä, Katrianne Lehtipalo, and Federico Bianchi
EGUsphere, https://doi.org/10.5194/egusphere-2025-2387, https://doi.org/10.5194/egusphere-2025-2387, 2025
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This study investigates New Particle Formation (NPF) in Milan, the most populated city in the Po Valley (Italy), using one year of particle number size distribution data (1.2–480 nm). NPF is enhanced under cleaner air conditions with lower pollution, reduced condensation sink, stronger ventilation, and stronger northwesterly winds (e.g., Foehn events). In contrast, longer air mass residence time in the Po Valley and higher air mass exposure to anthropogenic emissions suppress it.
Neil M. Donahue, Victoria Hofbauer, Henning Finkenzeller, Dominik Stolzenburg, Paulus S. Bauer, Randall Chiu, Lubna Dada, Jonathan Duplissy, Xu-Cheng He, Martin Heinritzi, Christopher R. Hoyle, Andreas Kürten, Aleksandr Kvashnin, Katrianne Lehtipalo, Naser Mahfouz, Vladimir Makhmutov, Roy L. Mauldin III, Ugo Molteni, Lauriane L. J. Quéléver, Matti Rissanen, Siegfried Schobesberger, Mario Simon, Andrea C. Wagner, Mingyi Wang, Chao Yan, Penglin Ye, Ilona Riipinen, Hamish Gordon, Joachim Curtius, Armin Hansel, Imad El Haddad, Markku Kulmala, Douglas R. Worsnop, Rainer Volkamer, Paul M. Winkler, Jasper Kirkby, and Richard Flagan
EGUsphere, https://doi.org/10.5194/egusphere-2025-2412, https://doi.org/10.5194/egusphere-2025-2412, 2025
This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
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We describe accurate measurement of particle formation and growth in the CERN CLOUD chamber, using a suite of gas- and particle-phase instruments. The interconnected measurements establish high accuracy in key particle properties and critically important gas-phase sulfuric acid. This is a template for accurate calibration of similar experiments and thus accurate determination of aerosol nucleation and growth rates, which are an important source of uncertainty in climate science.
Elie Bimenyimana, Jean Sciare, Michael Pikridas, Konstantina Oikonomou, Minas Iakovides, Emily Vasiliadou, Chrysanthos Savvides, and Nikos Mihalopoulos
EGUsphere, https://doi.org/10.5194/egusphere-2025-3234, https://doi.org/10.5194/egusphere-2025-3234, 2025
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Long-term (2015–2023) source apportionment analysis reveals that reduction in PM10 concentration levels from traffic in Cypriot cities is completely offset by the concomitant increase of uncontrolled PM from local sources (road dust resuspension, and domestic wood burning), along with rising Middle East PM from fossil fuel emissions. This poses a major challenge for Cyprus to comply with the stricter PM10 limits set by the new EU air quality directive.
Pan Wang, Yue Zhao, Jiandong Wang, Veli-Matti Kerminen, Jingkun Jiang, and Chenxi Li
Atmos. Chem. Phys., 25, 7431–7446, https://doi.org/10.5194/acp-25-7431-2025, https://doi.org/10.5194/acp-25-7431-2025, 2025
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We developed a numerical model to investigate the evolution of the charge state of newly formed atmospheric particles. Based on the simulation results, we successfully employed neural networks to predict particle charge states and estimate ion-induced nucleation rates. This study provides new insights into the dynamics of particle charging and introduces advanced methods for evaluating ion-induced nucleation in atmospheric research.
Jingnan Shi, Zhisheng Zhang, Li Li, Li Liu, Yaqing Zhou, Shuang Han, Shaobin Zhang, Minghua Liang, Linhong Xie, Weikang Ran, Shaowen Zhu, Hanbing Xu, Jiangchuan Tao, Alfred Wiedensohler, Qiaoqiao Wang, Qiyuan Wang, Nan Ma, and Juan Hong
EGUsphere, https://doi.org/10.5194/egusphere-2025-2643, https://doi.org/10.5194/egusphere-2025-2643, 2025
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This study examines aerosol hygroscopicity and mixing states at Mt. Hua (2060 m), a key free-tropospheric site in central China. We found size-dependent hygroscopicity, source-related variations, and humidity-driven processing, distinguishing this region from other high-altitude sites, which may provide key constraints for aerosol-cloud and regional climate models.
Anna Maria Neroladaki, Maria Tsagkaraki, Kyriaki Papoutsidaki, Kalliopi Tavernaraki, Filothei Boufidou, Pavlos Zarmpas, Irini Tsiodra, Eleni Liakakou, Aikaterini Bougiatioti, Giorgos Kouvarakis, Nikos Kalivitis, Christos Kaltsonoudis, Athanasios Karagioras, Dimitrios Balis, Konstantinos Mihailidis, Konstantinos Kourtidis, Stelios Myriokefalitakis, Nikos Hatzianastassiou, Spyros N. Pandis, Athanasios Nenes, Nikolaos Mihalopoulos, and Maria Kanakidou
EGUsphere, https://doi.org/10.5194/egusphere-2025-3223, https://doi.org/10.5194/egusphere-2025-3223, 2025
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Aerosol acidity affects aerosol composition and properties, and therefore climate, human health and ecosystems. We use summer and winter fine aerosol observations at 6 sites across Greece, and a thermodynamic model to calculate the spatial and seasonal variability of aerosol acidity. Aerosols were acidic to moderately acidic and more acidic during summer than winter. The importance of organics for aerosol acidity was small. Depending on location different factors controlled aerosol acidity.
Piaopiao Ke, Anna Lintunen, Pasi Kolari, Annalea Lohila, Santeri Tuovinen, Janne Lampilahti, Roseline Thakur, Maija Peltola, Otso Peräkylä, Tuomo Nieminen, Ekaterina Ezhova, Mari Pihlatie, Asta Laasonen, Markku Koskinen, Helena Rautakoski, Laura Heimsch, Tom Kokkonen, Aki Vähä, Ivan Mammarella, Steffen Noe, Jaana Bäck, Veli-Matti Kerminen, and Markku Kulmala
Biogeosciences, 22, 3235–3251, https://doi.org/10.5194/bg-22-3235-2025, https://doi.org/10.5194/bg-22-3235-2025, 2025
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Our research explores diverse ecosystems’ roles in climate cooling via the concept of CarbonSink+ potential. We measured CO2 uptake and local aerosol production in forests, farms, peatlands, urban gardens, and coastal areas across Finland and Estonia. The long-term data reveal that, while forests are vital with regard to CarbonSink+ potential, farms and urban gardens also play significant roles. These insights can help optimize management policy of natural resources to mitigate global warming.
Amauri C. Prudente Junior, Luiz A. T. Machado, Felipe S. Silva, Tercio Ambrizzi, Paulo Artaxo, Santiago Botia, Luan P. Cordeiro, Cleo Q. Dias Junior, Edmilson Freitas, Demerval S. Moreira, Christopher Pöhlker, Ivan M. C. Toro, Xiyan Xu, and Luciana V. Rizzo
EGUsphere, https://doi.org/10.5194/egusphere-2025-2869, https://doi.org/10.5194/egusphere-2025-2869, 2025
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This study propoes a new method of spatialization to estimate carbon fluxes in the Brazilian Amazon biome. To do so, was used a land surface model (JULES) and two vegetation properties. The results of this spatialization resulted in a carbon fluxes of -1.34 Pg C during the year of 2021 in the entire Brazilian Amazon biome being the states of Amapa and Acre main relevant regions of carbon source.
Sara M. Blichner, Theodore Khadir, Sini Talvinen, Paulo Artaxo, Liine Heikkinen, Harri Kokkola, Radovan Krejci, Muhammed Irfan, Twan van Noije, Tuukka Petäjä, Christopher Pöhlker, Øyvind Seland, Carl Svenhag, Antti Vartiainen, and Ilona Riipinen
EGUsphere, https://doi.org/10.5194/egusphere-2025-2559, https://doi.org/10.5194/egusphere-2025-2559, 2025
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This study looks at how well climate models capture the impact of rain on particles that help form cloud droplets. Using data from three measurement stations and applying both a correlation analysis and a machine learning approach, we found that models often miss how new particles form after rain and struggle in cold environments. This matters because these particles influence cloud formation and climate.
Daniel Köhler, Petri Räisänen, Tuomas Naakka, Kalle Nordling, and Victoria A. Sinclair
Weather Clim. Dynam., 6, 669–694, https://doi.org/10.5194/wcd-6-669-2025, https://doi.org/10.5194/wcd-6-669-2025, 2025
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We study the impacts of globally increasing sea surface temperatures and sea ice loss on the atmosphere in wintertime. In future climates, the jet stream shifts southward over the North Atlantic and extends further over Europe. Increasing sea surface temperatures drives these changes. The region of high activity of low-pressure systems is projected to move east towards Europe. Future increasing sea surface temperatures and sea ice loss contribute with similar magnitude to the eastward shift.
John Backman, Krista Luoma, Henri Servomaa, Ville Vakkari, and David Brus
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-284, https://doi.org/10.5194/essd-2025-284, 2025
Preprint under review for ESSD
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This work describes the in-situ aerosol measurements at the Arctic Sammaltunturi measurement station in Pallas in northern Finland. This data paper describes the instruments and the data post processing of key aerosol particle measurements that are relevant for cloud properties. Data reported here are part of the Pallas Cloud Experiment in 2022 (PaCE2022).
Janne Lampilahti, Pauli Paasonen, Santeri Tuovinen, Katrianne Lehtipalo, Veli-Matti Kerminen, and Markku Kulmala
Aerosol Research Discuss., https://doi.org/10.5194/ar-2025-19, https://doi.org/10.5194/ar-2025-19, 2025
Revised manuscript accepted for AR
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We developed a new automated method for calculating aerosol particle growth rates. Based on 14 years of measurements from Hyytiälä, Finland, the method produces results comparable to conventional approaches, while offering improved speed and ease of use.
Sami Daniel Harni, Lasse Johansson, Jarkko Ville Niemi, Ville Silvonen, Juan Andrés Casquero-Vera, Anu Kousa, Krista Luoma, Viet Le, David Brus, Konstantinos Doulgeris, Topi Rönkkö, Hanna Manninen, Tuukka Petäjä, and Hilkka Timonen
EGUsphere, https://doi.org/10.5194/egusphere-2025-1423, https://doi.org/10.5194/egusphere-2025-1423, 2025
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The 3-month measurement campaign at Espoo, Finland, in spring 2023. The measurement campaign studied the effect of the noise barrier on pollutant concentration gradients on one side of a major highway. The studied pollutants included PM10, PM2.5, lung deposited surface area (LDSA), particle number concentration (PNC), NO2, and black carbon (BC). The noise barrier was found to be effective in reducing, especially the concentration of particulate pollutants.
Clara Jaén, Mireia Udina, Roy Harrison, Joan O. Grimalt, and Barend L. Van Drooge
EGUsphere, https://doi.org/10.5194/egusphere-2025-2419, https://doi.org/10.5194/egusphere-2025-2419, 2025
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Distance changes air pollution in a city, but so does the time of the day and the year, due to varying emission sources and weather conditions. These changes were studied at ground level and 400 meters above the city, and showed that wood burning affected the air quality in winter, while products of atmospheric reaction processes dominated the air in summer. Traffic emissions arrive to the elevated site during the day, while they were trapped at lower level in the night.
J. Tapio Elomaa, Krista Luoma, Sami D. Harni, Aki Virkkula, Hilkka Timonen, and Tuukka Petäjä
Aerosol Research, 3, 293–314, https://doi.org/10.5194/ar-3-293-2025, https://doi.org/10.5194/ar-3-293-2025, 2025
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Black carbon (BC) is a pollutant from combustion that affects the climate and is harmful to health. We tested four different small BC sensors with a reference in Helsinki. The sensors compared well with the reference. As a sensor network they were able to capture differences in BC. Changes in temperature (T) and relative humidity (RH) caused error in the measurements. To reduce the effects of T and RH on BC sensors, more robust boxes should be developed, or corrections should be applied.
Xinyang Li, Tuomo Nieminen, Rima Baalbaki, Putian Zhou, Pauli Paasonen, Risto Makkonen, Martha Arbayani Zaidan, Nina Sarnela, Chao Yan, Tuija Jokinen, Imre Salma, Máté Vörösmarty, Tuukka Petäjä, Veli-Matti Kerminen, Markku Kulmala, and Lubna Dada
Aerosol Research, 3, 271–291, https://doi.org/10.5194/ar-3-271-2025, https://doi.org/10.5194/ar-3-271-2025, 2025
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Particle formation rate is one of the key factors in studying the physical properties of aerosols. By developing powerful and simple semi-empirical particle formation rate models, we can predict particle formation rates and compare them with real-time measurements to aid in discovering hidden particle formation mechanisms as well as global simulations of particle population to fill the knowledge gap caused by the uncertainty in aerosol cooling effects on Earth's atmosphere.
Ilona Láng-Ritter, Terhi Kristiina Laurila, Antti Mäkelä, Hilppa Gregow, and Victoria Anne Sinclair
Nat. Hazards Earth Syst. Sci., 25, 1697–1717, https://doi.org/10.5194/nhess-25-1697-2025, https://doi.org/10.5194/nhess-25-1697-2025, 2025
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We present a classification method for extratropical cyclones and windstorms and show their impacts on Finland's electricity grid by analysing the 92 most damaging windstorms (2005–2018). The south-west- and north-west-arriving windstorms cause the most damage to the power grid. The most relevant parameters for damage are the wind gust speed and extent of wind gusts. Windstorms are more frequent and damaging in autumn and winter, but weaker wind speeds in summer also cause significant damage.
Kimmo Teinilä, Sanna Saarikoski, Henna Lintusaari, Teemu Lepistö, Petteri Marjanen, Minna Aurela, Heidi Hellén, Toni Tykkä, Markus Lampimäki, Janne Lampilahti, Luis Barreira, Timo Mäkelä, Leena Kangas, Juha Hatakka, Sami Harni, Joel Kuula, Jarkko V. Niemi, Harri Portin, Jaakko Yli-Ojanperä, Ville Niemelä, Milja Jäppi, Katrianne Lehtipalo, Joonas Vanhanen, Liisa Pirjola, Hanna E. Manninen, Tuukka Petäjä, Topi Rönkkö, and Hilkka Timonen
Atmos. Chem. Phys., 25, 4907–4928, https://doi.org/10.5194/acp-25-4907-2025, https://doi.org/10.5194/acp-25-4907-2025, 2025
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Physical and chemical properties of particulate matter and concentrations of trace gases were measured in a street canyon in Helsinki, Finland, and an urban background site in January–February 2022 to investigate the effect of wintertime conditions on pollutants. State-of-the-art instruments and a mobile laboratory were used, and the measurement data were analysed further with modelling tools like positive matrix factorization and the Pollution Detection Algorithm.
Hannah Meyer, Konrad Kandler, Sylvain Dupont, Jerónimo Escribano, Jessica Girdwood, George Nikolich, Andrés Alastuey, Vicken Etyemezian, Cristina González Flórez, Adolfo González-Romero, Tareq Hussein, Mark Irvine, Peter Knippertz, Ottmar Möhler, Xavier Querol, Chris Stopford, Franziska Vogel, Frederik Weis, Andreas Wieser, Carlos Pérez García-Pando, and Martina Klose
EGUsphere, https://doi.org/10.5194/egusphere-2025-1531, https://doi.org/10.5194/egusphere-2025-1531, 2025
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Mineral dust particles emitted from dry soils are of various sizes, yet the abundance of very large particles is not well understood. Here we measured the dust size distribution from fine to giant particles at an emission source during a field campaign in Jordan (J-WADI) using multiple instruments. Our findings show that large particles make up a significant part of the total dust mass. This knowledge is essential to improve climate models and to predict dust impacts on climate and environment.
Rahul Ranjan, Liine Heikkinen, Lauri R. Ahonen, Krista Luoma, Paul Bowen, Tuukka Petäjä, Annica M. L. Ekman, Daniel G. Partridge, and Ilona Riipinen
EGUsphere, https://doi.org/10.5194/egusphere-2025-1602, https://doi.org/10.5194/egusphere-2025-1602, 2025
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We use multi-year measurements of cloud condensation nuclei (CCN) at a boreal forest site to inversely infer size-resolved aerosol chemical composition. We find that inorganic species are more enriched in the larger end (accumulation mode) of the sub-micron aerosol population while organics dominate the smaller end (Aitken mode). Our approach demonstrates the potential of long-term CCN measurements to infer size-resolved chemical composition of sub-micron aerosol.
Natalie M. Mahowald, Longlei Li, Julius Vira, Marje Prank, Douglas S. Hamilton, Hitoshi Matsui, Ron L. Miller, P. Louis Lu, Ezgi Akyuz, Daphne Meidan, Peter Hess, Heikki Lihavainen, Christine Wiedinmyer, Jenny Hand, Maria Grazia Alaimo, Célia Alves, Andres Alastuey, Paulo Artaxo, Africa Barreto, Francisco Barraza, Silvia Becagli, Giulia Calzolai, Shankararaman Chellam, Ying Chen, Patrick Chuang, David D. Cohen, Cristina Colombi, Evangelia Diapouli, Gaetano Dongarra, Konstantinos Eleftheriadis, Johann Engelbrecht, Corinne Galy-Lacaux, Cassandra Gaston, Dario Gomez, Yenny González Ramos, Roy M. Harrison, Chris Heyes, Barak Herut, Philip Hopke, Christoph Hüglin, Maria Kanakidou, Zsofia Kertesz, Zbigniew Klimont, Katriina Kyllönen, Fabrice Lambert, Xiaohong Liu, Remi Losno, Franco Lucarelli, Willy Maenhaut, Beatrice Marticorena, Randall V. Martin, Nikolaos Mihalopoulos, Yasser Morera-Gómez, Adina Paytan, Joseph Prospero, Sergio Rodríguez, Patricia Smichowski, Daniela Varrica, Brenna Walsh, Crystal L. Weagle, and Xi Zhao
Atmos. Chem. Phys., 25, 4665–4702, https://doi.org/10.5194/acp-25-4665-2025, https://doi.org/10.5194/acp-25-4665-2025, 2025
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Aerosol particles are an important part of the Earth system, but their concentrations are spatially and temporally heterogeneous, as well as being variable in size and composition. Here, we present a new compilation of PM2.5 and PM10 aerosol observations, focusing on the spatial variability across different observational stations, including composition, and demonstrate a method for comparing the data sets to model output.
Runlong Cai and Markku Kulmala
Aerosol Research, 3, 231–235, https://doi.org/10.5194/ar-3-231-2025, https://doi.org/10.5194/ar-3-231-2025, 2025
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The concept of the mean free path is fundamentally important to aerosol studies. Recent studies suggest that the mean free path of air (λair) could have been significantly overestimated by a factor of ~2. Here we show that this potential overestimation does not directly affect collision-induced aerosol dynamics in atmospheric conditions without high excess latent heat, while a similar influence of the mean free path of vapor (λ) on aerosol dynamics has been accounted for in current studies.
Guilherme Martins Pereira, Leonardo Yoshiaki Kamigauti, Rubens Fabio Pereira, Djacinto Monteiro dos Santos, Thayná da Silva Santos, José Vinicius Martins, Célia Alves, Cátia Gonçalves, Ismael Casotti Rienda, Nora Kováts, Thiago Nogueira, Luciana Rizzo, Paulo Artaxo, Regina Maura de Miranda, Marcia Akemi Yamasoe, Edmilson Dias de Freitas, Pérola de Castro Vasconcellos, and Maria de Fatima Andrade
Atmos. Chem. Phys., 25, 4587–4616, https://doi.org/10.5194/acp-25-4587-2025, https://doi.org/10.5194/acp-25-4587-2025, 2025
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The chemical composition of fine particulate matter was studied in the megacity of São Paulo (Brazil) during a polluted period. Vehicular-related sources remain relevant; however, a high contribution of biomass burning was observed and correlated with sample ecotoxicity. Emerging biomass burning sources, such as forest fires and sugarcane-bagasse-based power plants, highlight the need for additional control measures alongside stricter rules concerning vehicular emissions.
Dennis Niedermeier, Rasmus Hoffmann, Silvio Schmalfuss, Wiebke Frey, Fabian Senf, Olaf Hellmuth, Mira Pöhlker, and Frank Stratmann
Aerosol Research, 3, 219–230, https://doi.org/10.5194/ar-3-219-2025, https://doi.org/10.5194/ar-3-219-2025, 2025
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This study examines the deliquescence behavior of NaCl particles in a turbulent humidity field using the wind tunnel LACIS-T (Turbulent Leipzig Aerosol Cloud Interaction Simulator). The results show that turbulent relative humidity (RH) fluctuations affect the number of deliquesced particles, depending on the mean RH, strength of humidity fluctuations, and particle residence time. It turns out that, in addition to the mean RH, it is essential to consider humidity fluctuations and particle history when determining the phase state of the deliquescent particles.
Viet Le, Konstantinos Matthaios Doulgeris, Mika Komppula, John Backman, Gholamhossein Bagheri, Eberhard Bodenschatz, and David Brus
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-148, https://doi.org/10.5194/essd-2025-148, 2025
Preprint withdrawn
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This manuscript presents datasets collected during the Pallas Cloud Experiment in northern Finland during the autumn of 2022. We provide an overview of the payload that measured meteorological, cloud, and aerosol properties, and was deployed on tethered balloon systems across 21 flights. Additionally, we describe the datasets obtained, including details of the instruments on the payload.
Neha Deot, Vijay P. Kanawade, Alkistis Papetta, Rima Baalbaki, Michael Pikridas, Franco Marenco, Markku Kulmala, Jean Sciare, Katrianne Lehtipalo, and Tuija Jokinen
Aerosol Research, 3, 139–154, https://doi.org/10.5194/ar-3-139-2025, https://doi.org/10.5194/ar-3-139-2025, 2025
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We studied how nanoparticles form in the atmosphere at two different altitudes in Cyprus, focusing on how meteorology impacts this process. Using data from two sites, we found that air from lower regions carries particles up to higher areas, affecting air quality and potentially climate. Our findings help improve understanding of how particles form and grow in the air, which is important for predicting changes in climate and air pollution in the future.
Dominic Heslin-Rees, Peter Tunved, Diego Aliaga, Janne Lampilahti, Ilona Riipinen, Annica Ekman, Ki-Tae Park, Martina Mazzini, Stefania Gilardoni, Roseline Thakur, Kihong Park, Young Jun Yoon, Kitack Lee, Mikko Sipilä, Mauro Mazzola, and Radovan Krejci
Aerosol Research Discuss., https://doi.org/10.5194/ar-2025-11, https://doi.org/10.5194/ar-2025-11, 2025
Preprint under review for AR
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New particles form in the atmosphere and can influence the climate. We studied Arctic new particle formation (NPF) from 2022 to 2024 at the Zeppelin Observatory, on Svalbard. NPF occurs from April to November, peaking in late spring as sunlight increases. Some particles measured on-site grow large enough to seed clouds. Sunlight and existing aerosol particles strongly impact the likelihood of NPF, which mainly originates from marine regions, particularly the Greenland Sea.
Sebastian Brill, Björn Nillius, Jan-David Förster, Paulo Artaxo, Florian Ditas, Dennis Geis, Christian Gurk, Thomas Kenntner, Thomas Klimach, Mark Lamneck, Rafael Valiati, Bettina Weber, Stefan Wolff, Ulrich Pöschl, and Christopher Pöhlker
EGUsphere, https://doi.org/10.5194/egusphere-2025-295, https://doi.org/10.5194/egusphere-2025-295, 2025
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Highly resolved vertical profiles are crucial for understanding ecosystem-atmosphere interactions. We developed the robotic lift (RoLi) as a platform for vertical profile measurements at the Amazon Tall Tower Observatory in the central Amazon basin. Initial results reveal distinct spatiotemporal patterns in altitude profiles of temperature, humidity, fog, and aerosol properties, offering new insights into the diurnal dynamics of convective daytime mixing and stable nighttime stratification.
Fidel Pankratov, Alexander Mahura, Oleg Katz, Tuukka Petäjä, Valentin Popov, and Vladimir Masloboev
EGUsphere, https://doi.org/10.5194/egusphere-2025-393, https://doi.org/10.5194/egusphere-2025-393, 2025
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During polar springs low concentrations of atmospheric mercury (Hg) in the atmospheric surface layer are frequently observed. Presence of elevated Hg (in springs of 2010–2011) is not typical, and such increases are determined by the atmospheric transport at regional scales. Atmospheric trajectories showed that the source elevated Hg in the Arctic (at Amderma station) is linked with active phases of the volcanic eruptions in Iceland. It is an anomaly in terms of the global Hg pollution dynamics.
Hector Navarro-Barboza, Jordi Rovira, Vincenzo Obiso, Andrea Pozzer, Marta Via, Andres Alastuey, Xavier Querol, Noemi Perez, Marjan Savadkoohi, Gang Chen, Jesus Yus-Díez, Matic Ivancic, Martin Rigler, Konstantinos Eleftheriadis, Stergios Vratolis, Olga Zografou, Maria Gini, Benjamin Chazeau, Nicolas Marchand, Andre S. H. Prevot, Kaspar Dallenbach, Mikael Ehn, Krista Luoma, Tuukka Petäjä, Anna Tobler, Jaroslaw Necki, Minna Aurela, Hilkka Timonen, Jarkko Niemi, Olivier Favez, Jean-Eudes Petit, Jean-Philippe Putaud, Christoph Hueglin, Nicolas Pascal, Aurélien Chauvigné, Sébastien Conil, Marco Pandolfi, and Oriol Jorba
Atmos. Chem. Phys., 25, 2667–2694, https://doi.org/10.5194/acp-25-2667-2025, https://doi.org/10.5194/acp-25-2667-2025, 2025
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Brown carbon (BrC) absorbs ultraviolet (UV) and visible light, influencing climate. This study explores BrC's imaginary refractive index (k) using data from 12 European sites. Residential emissions are a major organic aerosol (OA) source in winter, while secondary organic aerosol (SOA) dominates in summer. Source-specific k values were derived, improving model accuracy. The findings highlight BrC's climate impact and emphasize source-specific constraints in atmospheric models.
Jianqiang Zhu, Guo Li, Uwe Kuhn, Bruno Backes Meller, Christopher Pöhlker, Paulo Artaxo, Ulrich Pöschl, Yafang Cheng, and Hang Su
EGUsphere, https://doi.org/10.5194/egusphere-2024-3911, https://doi.org/10.5194/egusphere-2024-3911, 2025
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The manuscript reports unique measurement data on sub-40 nm particles and ions, especially those smaller than 10 nm in the Amazon from December 2022 to January 2023. A large number of sub-3 nm particles and naturally charged ions were present in the Amazonia boundary layer, and they showed a clear diurnal variation. The research will contribute to a better understanding of atmospheric processes in the pristine environment.
Androniki Maragkidou, Tiia Grönholm, Laura Rautiainen, Juha Nikmo, Jukka-Pekka Jalkanen, Timo Mäkelä, Timo Anttila, Lauri Laakso, and Jaakko Kukkonen
Atmos. Chem. Phys., 25, 2443–2457, https://doi.org/10.5194/acp-25-2443-2025, https://doi.org/10.5194/acp-25-2443-2025, 2025
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The Baltic Sea's designation as a sulfur emission control area in 2006, with subsequent regulations, significantly reduced sulfur emissions from shipping. Our study analysed air quality data from 2003 to 2020 on the island Utö and employed modelling, showing a continuous decrease in SO2 concentrations since 2003 and thus evidencing the effectiveness of such regulations in improving air quality. It also underscored the importance of long-term, high-resolution monitoring at remote marine sites.
Benjamin Heutte, Nora Bergner, Hélène Angot, Jakob B. Pernov, Lubna Dada, Jessica A. Mirrielees, Ivo Beck, Andrea Baccarini, Matthew Boyer, Jessie M. Creamean, Kaspar R. Daellenbach, Imad El Haddad, Markus M. Frey, Silvia Henning, Tiia Laurila, Vaios Moschos, Tuukka Petäjä, Kerri A. Pratt, Lauriane L. J. Quéléver, Matthew D. Shupe, Paul Zieger, Tuija Jokinen, and Julia Schmale
Atmos. Chem. Phys., 25, 2207–2241, https://doi.org/10.5194/acp-25-2207-2025, https://doi.org/10.5194/acp-25-2207-2025, 2025
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Limited aerosol measurements in the central Arctic hinder our understanding of aerosol–climate interactions in the region. Our year-long observations of aerosol physicochemical properties during the MOSAiC expedition reveal strong seasonal variations in aerosol chemical composition, where the short-term variability is heavily affected by storms in the Arctic. Local wind-generated particles are shown to be an important source of cloud seeds, especially in autumn.
Maria Filioglou, Petri Tiitta, Xiaoxia Shang, Ari Leskinen, Pasi Ahola, Sanna Pätsi, Annika Saarto, Ville Vakkari, Uula Isopahkala, and Mika Komppula
Atmos. Chem. Phys., 25, 1639–1657, https://doi.org/10.5194/acp-25-1639-2025, https://doi.org/10.5194/acp-25-1639-2025, 2025
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Every year a vast number of people experience allergic reactions due to exposure to airborne pollen. These symptoms are concentration dependent; thus accurate information about the pollen load in the atmosphere is essential. Moreover, pollen grains and fragments of it are likely to contribute to cloud processes and suppress precipitation. Here, we estimate the concentration and cloud-relevant parameters of birch pollen in the atmosphere using observations from a PollyXT and a CL61 ceilometer.
James Brean, David C. S. Beddows, Eija Asmi, Aki Virkkula, Lauriane L. J. Quéléver, Mikko Sipilä, Floortje Van Den Heuvel, Thomas Lachlan-Cope, Anna Jones, Markus Frey, Angelo Lupi, Jiyeon Park, Young Jun Yoon, Rolf Weller, Giselle L. Marincovich, Gabriela C. Mulena, Roy M. Harrison, and Manuel Dall'Osto
Atmos. Chem. Phys., 25, 1145–1162, https://doi.org/10.5194/acp-25-1145-2025, https://doi.org/10.5194/acp-25-1145-2025, 2025
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Our results emphasise how understanding the geographical variation in surface types across the Antarctic is key to understanding secondary aerosol sources.
Yiliang Liu, Arttu Yli-Kujala, Fabian Schmidt-Ott, Sebastian Holm, Lauri Ahonen, Tommy Chan, Joonas Enroth, Joonas Vanhanen, Runlong Cai, Tuukka Petäjä, Markku Kulmala, Yang Chen, and Juha Kangasluoma
Atmos. Meas. Tech., 18, 431–442, https://doi.org/10.5194/amt-18-431-2025, https://doi.org/10.5194/amt-18-431-2025, 2025
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Accurate measurement of nanoparticles is crucial for understanding their impact on new particle formation and climate change. In this study, we calibrated the Particle Size Magnifier version 2.0 (PSM 2.0), using both laboratory-generated and atmospheric particles. Some differences were observed in the calibration results, with direct calibration using atmospheric particles enhancing measurement accuracy.
Shravan Deshmukh, Laurent Poulain, Birgit Wehner, Silvia Henning, Jean-Eudes Petit, Pauline Fombelle, Olivier Favez, Hartmut Herrmann, and Mira Pöhlker
Atmos. Chem. Phys., 25, 741–758, https://doi.org/10.5194/acp-25-741-2025, https://doi.org/10.5194/acp-25-741-2025, 2025
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Aerosol hygroscopicity has been investigated at a sub-urban site in Paris; analysis shows the sub-saturated regime's measured hygroscopicity and the chemically derived hygroscopic growth, shedding light on the large effect of external particle mixing and its influence on predicting hygroscopicity.
Xiansheng Liu, Xun Zhang, Marvin Dufresne, Tao Wang, Lijie Wu, Rosa Lara, Roger Seco, Marta Monge, Ana Maria Yáñez-Serrano, Marie Gohy, Paul Petit, Audrey Chevalier, Marie-Pierre Vagnot, Yann Fortier, Alexia Baudic, Véronique Ghersi, Grégory Gille, Ludovic Lanzi, Valérie Gros, Leïla Simon, Heidi Héllen, Stefan Reimann, Zoé Le Bras, Michelle Jessy Müller, David Beddows, Siqi Hou, Zongbo Shi, Roy M. Harrison, William Bloss, James Dernie, Stéphane Sauvage, Philip K. Hopke, Xiaoli Duan, Taicheng An, Alastair C. Lewis, James R. Hopkins, Eleni Liakakou, Nikolaos Mihalopoulos, Xiaohu Zhang, Andrés Alastuey, Xavier Querol, and Thérèse Salameh
Atmos. Chem. Phys., 25, 625–638, https://doi.org/10.5194/acp-25-625-2025, https://doi.org/10.5194/acp-25-625-2025, 2025
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This study examines BTEX (benzene, toluene, ethylbenzene, xylenes) pollution in urban areas across seven European countries. Analyzing data from 22 monitoring sites, we found traffic and industrial activities significantly impact BTEX levels, with peaks during rush hours. The risk from BTEX exposure remains moderate, especially in high-traffic and industrial zones, highlighting the need for targeted air quality management to protect public health and improve urban air quality.
Johannes Mikkola, Alexander Gohm, Victoria A. Sinclair, and Federico Bianchi
Atmos. Chem. Phys., 25, 511–533, https://doi.org/10.5194/acp-25-511-2025, https://doi.org/10.5194/acp-25-511-2025, 2025
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This study investigates the influence of valley floor inclination on diurnal winds and passive tracer transport within idealised mountain valleys using numerical simulations. The valley inclination strengthens the daytime up-valley winds but only up to a certain point. Beyond that critical angle, the winds weaken again. The inclined valleys transport the tracers higher up in the free troposphere, which would, for example, lead to higher potential for long-range transport.
Diego Aliaga, Victoria A. Sinclair, Radovan Krejci, Marcos Andrade, Paulo Artaxo, Luis Blacutt, Runlong Cai, Samara Carbone, Yvette Gramlich, Liine Heikkinen, Dominic Heslin-Rees, Wei Huang, Veli-Matti Kerminen, Alkuin Maximilian Koenig, Markku Kulmala, Paolo Laj, Valeria Mardoñez-Balderrama, Claudia Mohr, Isabel Moreno, Pauli Paasonen, Wiebke Scholz, Karine Sellegri, Laura Ticona, Gaëlle Uzu, Fernando Velarde, Alfred Wiedensohler, Doug Worsnop, Cheng Wu, Chen Xuemeng, Qiaozhi Zha, and Federico Bianchi
Aerosol Research, 3, 15–44, https://doi.org/10.5194/ar-3-15-2025, https://doi.org/10.5194/ar-3-15-2025, 2025
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This study examines new particle formation (NPF) in the Bolivian Andes at Chacaltaya mountain (CHC) and the urban El Alto–La Paz area (EAC). Days are clustered into four categories based on NPF intensity. Differences in particle size, precursor gases, and pollution levels are found. High NPF intensities increased Aitken mode particle concentrations at both sites, while volcanic influence selectively diminished NPF intensity at CHC but not EAC. This study highlights NPF dynamics in the Andes.
Ekaterina Ezhova, Topi Laanti, Anna Lintunen, Pasi Kolari, Tuomo Nieminen, Ivan Mammarella, Keijo Heljanko, and Markku Kulmala
Biogeosciences, 22, 257–288, https://doi.org/10.5194/bg-22-257-2025, https://doi.org/10.5194/bg-22-257-2025, 2025
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Machine learning (ML) models are gaining popularity in biogeosciences. They are applied as gap-filling methods and used to upscale carbon fluxes to larger areas. Here we use explainable artificial intelligence (XAI) methods to elucidate the performance of machine learning models for carbon dioxide fluxes in boreal forests. We show that statistically equal models treat input variables differently. XAI methods can help scientists make informed decisions when applying ML models in their research.
Joona Cornér, Clément Bouvier, Benjamin Doiteau, Florian Pantillon, and Victoria A. Sinclair
Nat. Hazards Earth Syst. Sci., 25, 207–229, https://doi.org/10.5194/nhess-25-207-2025, https://doi.org/10.5194/nhess-25-207-2025, 2025
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Classification reduces the considerable variability between extratropical cyclones (ETCs) and thus simplifies studying their representation in climate models and changes in the future climate. In this paper we present an objective classification of ETCs using measures of ETC intensity. This is motivated by the aim of finding a set of ETC intensity measures which together comprehensively describe both the dynamical and impact-relevant nature of ETC intensity.
Pamela A. Dominutti, Jean-Luc Jaffrezo, Anouk Marsal, Takoua Mhadhbi, Rhabira Elazzouzi, Camille Rak, Fabrizia Cavalli, Jean-Philippe Putaud, Aikaterini Bougiatioti, Nikolaos Mihalopoulos, Despina Paraskevopoulou, Ian Mudway, Athanasios Nenes, Kaspar R. Daellenbach, Catherine Banach, Steven J. Campbell, Hana Cigánková, Daniele Contini, Greg Evans, Maria Georgopoulou, Manuella Ghanem, Drew A. Glencross, Maria Rachele Guascito, Hartmut Herrmann, Saima Iram, Maja Jovanović, Milena Jovašević-Stojanović, Markus Kalberer, Ingeborg M. Kooter, Suzanne E. Paulson, Anil Patel, Esperanza Perdrix, Maria Chiara Pietrogrande, Pavel Mikuška, Jean-Jacques Sauvain, Katerina Seitanidi, Pourya Shahpoury, Eduardo J. d. S. Souza, Sarah Steimer, Svetlana Stevanovic, Guillaume Suarez, P. S. Ganesh Subramanian, Battist Utinger, Marloes F. van Os, Vishal Verma, Xing Wang, Rodney J. Weber, Yuhan Yang, Xavier Querol, Gerard Hoek, Roy M. Harrison, and Gaëlle Uzu
Atmos. Meas. Tech., 18, 177–195, https://doi.org/10.5194/amt-18-177-2025, https://doi.org/10.5194/amt-18-177-2025, 2025
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In this work, 20 labs worldwide collaborated to evaluate the measurement of air pollution's oxidative potential (OP), a key indicator of its harmful effects. The study aimed to identify disparities in the widely used OP dithiothreitol assay and assess the consistency of OP among labs using the same protocol. The results showed that half of the labs achieved acceptable results. However, variability was also found, highlighting the need for standardisation in OP procedures.
Otso Peräkylä, Erkka Rinne, Ekaterina Ezhova, Anna Lintunen, Annalea Lohila, Juho Aalto, Mika Aurela, Pasi Kolari, and Markku Kulmala
Biogeosciences, 22, 153–179, https://doi.org/10.5194/bg-22-153-2025, https://doi.org/10.5194/bg-22-153-2025, 2025
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Forests are seen as good for climate. Yet, in areas with snow, trees break up the white snow surface and absorb more sunlight than open areas. This has a warming effect, negating some of the climate benefit of trees. We studied two site pairs in Finland, both with an open peatland and a forest. We found that the later the snow melts, the more extra energy the forest absorbs as compared to the peatland. This has implications for the future, as snow cover duration is affected by global warming.
Petri Clusius, Metin Baykara, Carlton Xavier, Putian Zhou, Juniper Tyree, Benjamin Foreback, Mikko Äijälä, Frans Graeffe, Tuukka Petäjä, Markku Kulmala, Pauli Paasonen, Paul I. Palmer, and Michael Boy
EGUsphere, https://doi.org/10.5194/egusphere-2025-39, https://doi.org/10.5194/egusphere-2025-39, 2025
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Cloud condensation nuclei are necessary to form clouds, and their size distribution affects cloud properties and therefore Earth’s energy budget. This study modelled the origins of cloud condensation nuclei at SMEAR II, Hyytiälä, Finland, and found that primary emissions and new particle formation separately contribute to more than half of the condensation nuclei, but they suppress each other, leading to current concentrations. Largest condensation nuclei originated mostly from emissions.
Ari Laaksonen
Aerosol Research, 2, 343–351, https://doi.org/10.5194/ar-2-343-2024, https://doi.org/10.5194/ar-2-343-2024, 2024
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Insoluble aerosol particles such as minerals and black carbon can trigger freezing inside clouds, which leads to rain formation. However, both particle types are relatively poor nuclei for cloud droplets. In this work, theoretical calculations are presented about the ability of surface-tension-reducing compounds to promote cloud drop formation around insoluble aerosols. The calculations indicate that such surfactants can be efficient in “smuggling” insoluble particles into cloud droplets.
Matthew Boyer, Diego Aliaga, Lauriane L. J. Quéléver, Silvia Bucci, Hélène Angot, Lubna Dada, Benjamin Heutte, Lisa Beck, Marina Duetsch, Andreas Stohl, Ivo Beck, Tiia Laurila, Nina Sarnela, Roseline C. Thakur, Branka Miljevic, Markku Kulmala, Tuukka Petäjä, Mikko Sipilä, Julia Schmale, and Tuija Jokinen
Atmos. Chem. Phys., 24, 12595–12621, https://doi.org/10.5194/acp-24-12595-2024, https://doi.org/10.5194/acp-24-12595-2024, 2024
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We analyze the seasonal cycle and sources of gases that are relevant for the formation of aerosol particles in the central Arctic. Since theses gases can form new particles, they can influence Arctic climate. We show that the sources of these gases are associated with changes in the Arctic environment during the year, especially with respect to sea ice. Therefore, the concentration of these gases will likely change in the future as the Arctic continues to warm.
Flossie Brown, Gerd Folberth, Stephen Sitch, Paulo Artaxo, Marijn Bauters, Pascal Boeckx, Alexander W. Cheesman, Matteo Detto, Ninong Komala, Luciana Rizzo, Nestor Rojas, Ines dos Santos Vieira, Steven Turnock, Hans Verbeeck, and Alfonso Zambrano
Atmos. Chem. Phys., 24, 12537–12555, https://doi.org/10.5194/acp-24-12537-2024, https://doi.org/10.5194/acp-24-12537-2024, 2024
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Ozone is a pollutant that is detrimental to human and plant health. Ozone monitoring sites in the tropics are limited, so models are often used to understand ozone exposure. We use measurements from the tropics to evaluate ozone from the UK Earth system model, UKESM1. UKESM1 is able to capture the pattern of ozone in the tropics, except in southeast Asia, although it systematically overestimates it at all sites. This work highlights that UKESM1 can capture seasonal and hourly variability.
Shahzad Gani, Louise Arnal, Lucy Beattie, John Hillier, Sam Illingworth, Tiziana Lanza, Solmaz Mohadjer, Karoliina Pulkkinen, Heidi Roop, Iain Stewart, Kirsten von Elverfeldt, and Stephanie Zihms
Geosci. Commun., 7, 251–266, https://doi.org/10.5194/gc-7-251-2024, https://doi.org/10.5194/gc-7-251-2024, 2024
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Science communication in geosciences has societal and scientific value but often operates in “shadowlands”. This editorial highlights these issues and proposes potential solutions. Our objective is to create a transparent and responsible geoscience communication landscape, fostering scientific progress, the well-being of scientists, and societal benefits.
Sami D. Harni, Minna Aurela, Sanna Saarikoski, Jarkko V. Niemi, Harri Portin, Hanna Manninen, Ville Leinonen, Pasi Aalto, Phil K. Hopke, Tuukka Petäjä, Topi Rönkkö, and Hilkka Timonen
Atmos. Chem. Phys., 24, 12143–12160, https://doi.org/10.5194/acp-24-12143-2024, https://doi.org/10.5194/acp-24-12143-2024, 2024
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In this study, particle number size distribution data were used in a novel way in positive matrix factorization analysis to find aerosol source profiles in the area. Measurements were made in Helsinki at a street canyon and urban background sites between February 2015 and June 2019. Five different aerosol sources were identified. These sources underline the significance of traffic-related emissions in urban environments despite recent improvements in emission reduction technologies.
Valeria Mardoñez-Balderrama, Griša Močnik, Marco Pandolfi, Robin L. Modini, Fernando Velarde, Laura Renzi, Angela Marinoni, Jean-Luc Jaffrezo, Isabel Moreno R., Diego Aliaga, Federico Bianchi, Claudia Mohr, Martin Gysel-Beer, Patrick Ginot, Radovan Krejci, Alfred Wiedensohler, Gaëlle Uzu, Marcos Andrade, and Paolo Laj
Atmos. Chem. Phys., 24, 12055–12077, https://doi.org/10.5194/acp-24-12055-2024, https://doi.org/10.5194/acp-24-12055-2024, 2024
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Levels of black carbon (BC) are scarcely reported in the Southern Hemisphere, especially in high-altitude conditions. This study provides insight into the concentration level, variability, and optical properties of BC in La Paz and El Alto and at the Chacaltaya Global Atmosphere Watch Station. Two methods of source apportionment of absorption were tested and compared showing traffic as the main contributor to absorption in the urban area, in addition to biomass and open waste burning.
Franziska Vogel, Michael P. Adams, Larissa Lacher, Polly B. Foster, Grace C. E. Porter, Barbara Bertozzi, Kristina Höhler, Julia Schneider, Tobias Schorr, Nsikanabasi S. Umo, Jens Nadolny, Zoé Brasseur, Paavo Heikkilä, Erik S. Thomson, Nicole Büttner, Martin I. Daily, Romy Fösig, Alexander D. Harrison, Jorma Keskinen, Ulrike Proske, Jonathan Duplissy, Markku Kulmala, Tuukka Petäjä, Ottmar Möhler, and Benjamin J. Murray
Atmos. Chem. Phys., 24, 11737–11757, https://doi.org/10.5194/acp-24-11737-2024, https://doi.org/10.5194/acp-24-11737-2024, 2024
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Primary ice formation in clouds strongly influences their properties; hence, it is important to understand the sources of ice-nucleating particles (INPs) and their variability. We present 2 months of INP measurements in a Finnish boreal forest using a new semi-autonomous INP counting device based on gas expansion. These results show strong variability in INP concentrations, and we present a case that the INPs we observe are, at least some of the time, of biological origin.
Markku Kulmala, Santeri Tuovinen, Sander Mirme, Paap Koemets, Lauri Ahonen, Yongchun Liu, Heikki Junninen, Tuukka Petäjä, and Veli-Matti Kerminen
Aerosol Research, 2, 291–301, https://doi.org/10.5194/ar-2-291-2024, https://doi.org/10.5194/ar-2-291-2024, 2024
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With the recently developed CIC (Cluster Ion Counter) instrument, we can observe dynamics of small air ions and intermediate air ions. Furthermore, we can observe condensation sink and formation and growth rates for intermediated ions.
Zoé Brasseur, Julia Schneider, Janne Lampilahti, Ville Vakkari, Victoria A. Sinclair, Christina J. Williamson, Carlton Xavier, Dmitri Moisseev, Markus Hartmann, Pyry Poutanen, Markus Lampimäki, Markku Kulmala, Tuukka Petäjä, Katrianne Lehtipalo, Erik S. Thomson, Kristina Höhler, Ottmar Möhler, and Jonathan Duplissy
Atmos. Chem. Phys., 24, 11305–11332, https://doi.org/10.5194/acp-24-11305-2024, https://doi.org/10.5194/acp-24-11305-2024, 2024
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Ice-nucleating particles (INPs) strongly influence the formation of clouds by initiating the formation of ice crystals. However, very little is known about the vertical distribution of INPs in the atmosphere. Here, we present aircraft measurements of INP concentrations above the Finnish boreal forest. Results show that near-surface INPs are efficiently transported and mixed within the boundary layer and occasionally reach the free troposphere.
Martti Honkanen, Mika Aurela, Juha Hatakka, Lumi Haraguchi, Sami Kielosto, Timo Mäkelä, Jukka Seppälä, Simo-Matti Siiriä, Ken Stenbäck, Juha-Pekka Tuovinen, Pasi Ylöstalo, and Lauri Laakso
Biogeosciences, 21, 4341–4359, https://doi.org/10.5194/bg-21-4341-2024, https://doi.org/10.5194/bg-21-4341-2024, 2024
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The exchange of CO2 between the sea and the atmosphere was studied in the Archipelago Sea, Baltic Sea, in 2017–2021, using an eddy covariance technique. The sea acted as a net source of CO2 with an average yearly emission of 27.1 gC m-2 yr-1, indicating that the marine ecosystem respired carbon that originated elsewhere. The yearly CO2 emission varied between 18.2–39.2 gC m-2 yr-1, mostly due to the yearly variation of ecosystem carbon uptake.
Jinbo Wang, Jiaping Wang, Yuxuan Zhang, Tengyu Liu, Xuguang Chi, Xin Huang, Dafeng Ge, Shiyi Lai, Caijun Zhu, Lei Wang, Qiaozhi Zha, Ximeng Qi, Wei Nie, Congbin Fu, and Aijun Ding
Atmos. Chem. Phys., 24, 11063–11080, https://doi.org/10.5194/acp-24-11063-2024, https://doi.org/10.5194/acp-24-11063-2024, 2024
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In this study, we found large spatial discrepancies in the physical and chemical properties of black carbon over the Tibetan Plateau (TP). Elevated anthropogenic emissions from low-altitude regions can significantly change the mass concentration, mixing state and chemical composition of black-carbon-containing aerosol in the TP region, further altering its light absorption ability. Our study emphasizes the vulnerability of remote plateau regions to intense anthropogenic influences.
Teemu Lepistö, Henna Lintusaari, Laura Salo, Ville Silvonen, Luis M. F. Barreira, Jussi Hoivala, Lassi Markkula, Jarkko V. Niemi, Jakub Ondracek, Kimmo Teinilä, Hanna E. Manninen, Sanna Saarikoski, Hilkka Timonen, Miikka Dal Maso, and Topi Rönkkö
Aerosol Research, 2, 271–289, https://doi.org/10.5194/ar-2-271-2024, https://doi.org/10.5194/ar-2-271-2024, 2024
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The performances of different particle lung-deposited surface area (LDSAal) measurement methods (Partector, ELPI+, SMPS/DMPS) were compared in ambient conditions. As LDSAal is a health-relevant metric and rather easy to utilise in air quality monitoring, it is crucial to know how the different methods agree, as there are clear differences in their operation. In all, a comparison of different methods can be complicated; still, the methods agree rather well in terms of local pollution (< 400 nm).
Jia Sun, Markus Hermann, Kay Weinhold, Maik Merkel, Wolfram Birmili, Yifan Yang, Thomas Tuch, Harald Flentje, Björn Briel, Ludwig Ries, Cedric Couret, Michael Elsasser, Ralf Sohmer, Klaus Wirtz, Frank Meinhardt, Maik Schütze, Olaf Bath, Bryan Hellack, Veli-Matti Kerminen, Markku Kulmala, Nan Ma, and Alfred Wiedensohler
Atmos. Chem. Phys., 24, 10667–10687, https://doi.org/10.5194/acp-24-10667-2024, https://doi.org/10.5194/acp-24-10667-2024, 2024
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We investigated the characteristics of new particle formation (NPF) for various environments from urban background to high Alpine and the impacts of NPF on cloud condensation nuclei and aerosol radiative forcing. NPF features differ between site categories, implying the crucial role of local environmental factors such as the degree of emissions and meteorological conditions. The results also underscore the importance of local environments when assessing the impact of NPF on climate in models.
Shengqian Zhou, Ying Chen, Shan Huang, Xianda Gong, Guipeng Yang, Honghai Zhang, Hartmut Herrmann, Alfred Wiedensohler, Laurent Poulain, Yan Zhang, Fanghui Wang, Zongjun Xu, and Ke Yan
Earth Syst. Sci. Data, 16, 4267–4290, https://doi.org/10.5194/essd-16-4267-2024, https://doi.org/10.5194/essd-16-4267-2024, 2024
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Dimethyl sulfide (DMS) is a crucial natural reactive gas in the global climate system due to its great contribution to aerosols and subsequent impact on clouds over remote oceans. Leveraging machine learning techniques, we constructed a long-term global sea surface DMS gridded dataset with daily resolution. Compared to previous datasets, our new dataset holds promise for improving atmospheric chemistry modeling and advancing our comprehension of the climate effects associated with oceanic DMS.
Alex Rowell, James Brean, David C. S. Beddows, Zongbo Shi, Avinash Kumar, Matti Rissanen, Miikka Dal Maso, Peter Mettke, Kay Weinhold, Maik Merkel, and Roy M. Harrison
Atmos. Chem. Phys., 24, 10349–10361, https://doi.org/10.5194/acp-24-10349-2024, https://doi.org/10.5194/acp-24-10349-2024, 2024
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Ions enhance the formation and growth rates of new particles, affecting the Earth's radiation budget. Despite these effects, there is little published data exploring the sources of ions in the urban environment and their role in new particle formation (NPF). Here we show that natural ion sources dominate in urban environments, while traffic is a secondary source. Ions contribute up to 12.7 % of the formation rate of particles, indicating that they are important for forming urban PM.
Romanos Foskinis, Ghislain Motos, Maria I. Gini, Olga Zografou, Kunfeng Gao, Stergios Vratolis, Konstantinos Granakis, Ville Vakkari, Kalliopi Violaki, Andreas Aktypis, Christos Kaltsonoudis, Zongbo Shi, Mika Komppula, Spyros N. Pandis, Konstantinos Eleftheriadis, Alexandros Papayannis, and Athanasios Nenes
Atmos. Chem. Phys., 24, 9827–9842, https://doi.org/10.5194/acp-24-9827-2024, https://doi.org/10.5194/acp-24-9827-2024, 2024
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Analysis of modeling, in situ, and remote sensing measurements reveals the microphysical state of orographic clouds and their response to aerosol from the boundary layer and free troposphere. We show that cloud response to aerosol is robust, as predicted supersaturation and cloud droplet number levels agree with those determined from in-cloud measurements. The ability to determine if clouds are velocity- or aerosol-limited allows for novel model constraints and remote sensing products.
Alex Rowell, James Brean, David C. S. Beddows, Tuukka Petäjä, Máté Vörösmarty, Imre Salma, Jarkko V. Niemi, Hanna E. Manninen, Dominik van Pinxteren, Thomas Tuch, Kay Weinhold, Zongbo Shi, and Roy M. Harrison
Atmos. Chem. Phys., 24, 9515–9531, https://doi.org/10.5194/acp-24-9515-2024, https://doi.org/10.5194/acp-24-9515-2024, 2024
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Different sources of airborne particles in the atmospheres of four European cities were distinguished by recognising their particle size distributions using a statistical procedure, positive matrix factorisation. The various sources responded differently to the changes in emissions associated with COVID-19 lockdowns, and the reasons are investigated. While traffic emissions generally decreased, particles formed from reactions of atmospheric gases decreased in some cities but increased in others.
Jutta Kesti, Ewan J. O'Connor, Anne Hirsikko, John Backman, Maria Filioglou, Anu-Maija Sundström, Juha Tonttila, Heikki Lihavainen, Hannele Korhonen, and Eija Asmi
Atmos. Chem. Phys., 24, 9369–9386, https://doi.org/10.5194/acp-24-9369-2024, https://doi.org/10.5194/acp-24-9369-2024, 2024
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The study combines aerosol particle measurements at the surface and vertical profiling of the atmosphere with a scanning Doppler lidar to investigate how particle transportation together with boundary layer evolution can affect particle and SO2 concentrations at the surface in the Arabian Peninsula region. The instrumentation enabled us to see elevated nucleation mode particle and SO2 concentrations at the surface when air masses transported from polluted areas are mixed in the boundary layer.
Luiz A. T. Machado, Jürgen Kesselmeier, Santiago Botía, Hella van Asperen, Meinrat O. Andreae, Alessandro C. de Araújo, Paulo Artaxo, Achim Edtbauer, Rosaria R. Ferreira, Marco A. Franco, Hartwig Harder, Sam P. Jones, Cléo Q. Dias-Júnior, Guido G. Haytzmann, Carlos A. Quesada, Shujiro Komiya, Jost Lavric, Jos Lelieveld, Ingeborg Levin, Anke Nölscher, Eva Pfannerstill, Mira L. Pöhlker, Ulrich Pöschl, Akima Ringsdorf, Luciana Rizzo, Ana M. Yáñez-Serrano, Susan Trumbore, Wanda I. D. Valenti, Jordi Vila-Guerau de Arellano, David Walter, Jonathan Williams, Stefan Wolff, and Christopher Pöhlker
Atmos. Chem. Phys., 24, 8893–8910, https://doi.org/10.5194/acp-24-8893-2024, https://doi.org/10.5194/acp-24-8893-2024, 2024
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Composite analysis of gas concentration before and after rainfall, during the day and night, gives insight into the complex relationship between trace gas variability and precipitation. The analysis helps us to understand the sources and sinks of trace gases within a forest ecosystem. It elucidates processes that are not discernible under undisturbed conditions and contributes to a deeper understanding of the trace gas life cycle and its intricate interactions with cloud dynamics in the Amazon.
Manfred Wendisch, Susanne Crewell, André Ehrlich, Andreas Herber, Benjamin Kirbus, Christof Lüpkes, Mario Mech, Steven J. Abel, Elisa F. Akansu, Felix Ament, Clémantyne Aubry, Sebastian Becker, Stephan Borrmann, Heiko Bozem, Marlen Brückner, Hans-Christian Clemen, Sandro Dahlke, Georgios Dekoutsidis, Julien Delanoë, Elena De La Torre Castro, Henning Dorff, Regis Dupuy, Oliver Eppers, Florian Ewald, Geet George, Irina V. Gorodetskaya, Sarah Grawe, Silke Groß, Jörg Hartmann, Silvia Henning, Lutz Hirsch, Evelyn Jäkel, Philipp Joppe, Olivier Jourdan, Zsofia Jurányi, Michail Karalis, Mona Kellermann, Marcus Klingebiel, Michael Lonardi, Johannes Lucke, Anna E. Luebke, Maximilian Maahn, Nina Maherndl, Marion Maturilli, Bernhard Mayer, Johanna Mayer, Stephan Mertes, Janosch Michaelis, Michel Michalkov, Guillaume Mioche, Manuel Moser, Hanno Müller, Roel Neggers, Davide Ori, Daria Paul, Fiona M. Paulus, Christian Pilz, Felix Pithan, Mira Pöhlker, Veronika Pörtge, Maximilian Ringel, Nils Risse, Gregory C. Roberts, Sophie Rosenburg, Johannes Röttenbacher, Janna Rückert, Michael Schäfer, Jonas Schaefer, Vera Schemann, Imke Schirmacher, Jörg Schmidt, Sebastian Schmidt, Johannes Schneider, Sabrina Schnitt, Anja Schwarz, Holger Siebert, Harald Sodemann, Tim Sperzel, Gunnar Spreen, Bjorn Stevens, Frank Stratmann, Gunilla Svensson, Christian Tatzelt, Thomas Tuch, Timo Vihma, Christiane Voigt, Lea Volkmer, Andreas Walbröl, Anna Weber, Birgit Wehner, Bruno Wetzel, Martin Wirth, and Tobias Zinner
Atmos. Chem. Phys., 24, 8865–8892, https://doi.org/10.5194/acp-24-8865-2024, https://doi.org/10.5194/acp-24-8865-2024, 2024
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The Arctic is warming faster than the rest of the globe. Warm-air intrusions (WAIs) into the Arctic may play an important role in explaining this phenomenon. Cold-air outbreaks (CAOs) out of the Arctic may link the Arctic climate changes to mid-latitude weather. In our article, we describe how to observe air mass transformations during CAOs and WAIs using three research aircraft instrumented with state-of-the-art remote-sensing and in situ measurement devices.
Baseerat Romshoo, Jaikrishna Patil, Tobias Michels, Thomas Müller, Marius Kloft, and Mira Pöhlker
Atmos. Chem. Phys., 24, 8821–8846, https://doi.org/10.5194/acp-24-8821-2024, https://doi.org/10.5194/acp-24-8821-2024, 2024
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Through the use of our machine-learning-based optical model, realistic BC morphologies can be incorporated into atmospheric science applications that require highly accurate results with minimal computational resources. The results of the study demonstrate that the predictions of single-scattering albedo (ω) and mass absorption cross-section (MAC) were improved over the conventional Mie-based predictions when using the machine learning method.
Marco A. Franco, Rafael Valiati, Bruna A. Holanda, Bruno B. Meller, Leslie A. Kremper, Luciana V. Rizzo, Samara Carbone, Fernando G. Morais, Janaína P. Nascimento, Meinrat O. Andreae, Micael A. Cecchini, Luiz A. T. Machado, Milena Ponczek, Ulrich Pöschl, David Walter, Christopher Pöhlker, and Paulo Artaxo
Atmos. Chem. Phys., 24, 8751–8770, https://doi.org/10.5194/acp-24-8751-2024, https://doi.org/10.5194/acp-24-8751-2024, 2024
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The Amazon wet-season atmosphere was studied at the Amazon Tall Tower Observatory site, revealing vertical variations (between 60 and 325 m) in natural aerosols. Daytime mixing contrasted with nighttime stratification, with distinct rain-induced changes in aerosol populations. Notably, optical property recovery at higher levels was faster, while near-canopy aerosols showed higher scattering efficiency. These findings enhance our understanding of aerosol impacts on climate dynamics.
Yusheng Zhang, Feixue Zheng, Zemin Feng, Chaofan Lian, Weigang Wang, Xiaolong Fan, Wei Ma, Zhuohui Lin, Chang Li, Gen Zhang, Chao Yan, Ying Zhang, Veli-Matti Kerminen, Federico Bianch, Tuukka Petäjä, Juha Kangasluoma, Markku Kulmala, and Yongchun Liu
Atmos. Chem. Phys., 24, 8569–8587, https://doi.org/10.5194/acp-24-8569-2024, https://doi.org/10.5194/acp-24-8569-2024, 2024
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The nitrous acid (HONO) budget was validated during a COVID-19 lockdown event. The main conclusions are (1) HONO concentrations showed a significant decrease from 0.97 to 0.53 ppb during lockdown; (2) vehicle emissions accounted for 53 % of nighttime sources, with the heterogeneous conversion of NO2 on ground surfaces more important than aerosol; and (3) the dominant daytime source shifted from the homogenous reaction between NO and OH (51 %) to nitrate photolysis (53 %) during lockdown.
Ningjin Xu, Chen Le, David R. Cocker, Kunpeng Chen, Ying-Hsuan Lin, and Don R. Collins
Atmos. Meas. Tech., 17, 4227–4243, https://doi.org/10.5194/amt-17-4227-2024, https://doi.org/10.5194/amt-17-4227-2024, 2024
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A flow-through reactor was developed that exposes known mixtures of gases or ambient air to very high concentrations of the oxidants that are responsible for much of the chemistry that takes place in the atmosphere. Like other reactors of its type, it is primarily used to study the formation of particulate matter from the oxidation of common gases. Unlike other reactors of its type, it can simulate the chemical reactions that occur in liquid water that is present in particles or cloud droplets.
Stelios Myriokefalitakis, Matthias Karl, Kim A. Weiss, Dimitris Karagiannis, Eleni Athanasopoulou, Anastasia Kakouri, Aikaterini Bougiatioti, Eleni Liakakou, Iasonas Stavroulas, Georgios Papangelis, Georgios Grivas, Despina Paraskevopoulou, Orestis Speyer, Nikolaos Mihalopoulos, and Evangelos Gerasopoulos
Atmos. Chem. Phys., 24, 7815–7835, https://doi.org/10.5194/acp-24-7815-2024, https://doi.org/10.5194/acp-24-7815-2024, 2024
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A state-of-the-art thermodynamic model has been coupled with the city-scale chemistry transport model EPISODE–CityChem to investigate the equilibrium between the inorganic gas and aerosol phases over the greater Athens area, Greece. The simulations indicate that the formation of nitrates in an urban environment is significantly affected by local nitrogen oxide emissions, as well as ambient temperature, relative humidity, photochemical activity, and the presence of non-volatile cations.
Jing Duan, Ru-Jin Huang, Ying Wang, Wei Xu, Haobin Zhong, Chunshui Lin, Wei Huang, Yifang Gu, Jurgita Ovadnevaite, Darius Ceburnis, and Colin O'Dowd
Atmos. Chem. Phys., 24, 7687–7698, https://doi.org/10.5194/acp-24-7687-2024, https://doi.org/10.5194/acp-24-7687-2024, 2024
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The chemical composition of atmospheric particles has shown significant changes in recent years. We investigated the potential effects of changes in inorganics on aerosol water uptake and, thus, secondary organic aerosol formation in wintertime haze based on the size-resolved measurements of non-refractory fine particulate matter (NR-PM2.5) in Xi’an, northwestern China. We highlight the key role of aerosol water as a medium to link inorganics and organics in their multiphase processes.
Zihan Zhu, Javier González-Rocha, Yifan Ding, Isis Frausto-Vicencio, Sajjan Heerah, Akula Venkatram, Manvendra Dubey, Don Collins, and Francesca M. Hopkins
Atmos. Meas. Tech., 17, 3883–3895, https://doi.org/10.5194/amt-17-3883-2024, https://doi.org/10.5194/amt-17-3883-2024, 2024
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Increases in agriculture, oil and gas, and waste management activities have contributed to the increase in atmospheric methane levels and resultant climate warming. In this paper, we explore the use of small uncrewed aircraft systems (sUASs) and AirCore technology to detect and quantify methane emissions. Results from field experiments demonstrate that sUASs and AirCore technology can be effective for detecting and quantifying methane emissions in near real time.
Karam Mansour, Stefano Decesari, Darius Ceburnis, Jurgita Ovadnevaite, Lynn M. Russell, Marco Paglione, Laurent Poulain, Shan Huang, Colin O'Dowd, and Matteo Rinaldi
Earth Syst. Sci. Data, 16, 2717–2740, https://doi.org/10.5194/essd-16-2717-2024, https://doi.org/10.5194/essd-16-2717-2024, 2024
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We propose and evaluate machine learning predictive algorithms to model freshly formed biogenic methanesulfonic acid and sulfate concentrations. The long-term constructed dataset covers the North Atlantic at an unprecedented resolution. The improved parameterization of biogenic sulfur aerosols at regional scales is essential for determining their radiative forcing, which could help further understand marine-aerosol–cloud interactions and reduce uncertainties in climate models
Marco Paglione, David C. S. Beddows, Anna Jones, Thomas Lachlan-Cope, Matteo Rinaldi, Stefano Decesari, Francesco Manarini, Mara Russo, Karam Mansour, Roy M. Harrison, Andrea Mazzanti, Emilio Tagliavini, and Manuel Dall'Osto
Atmos. Chem. Phys., 24, 6305–6322, https://doi.org/10.5194/acp-24-6305-2024, https://doi.org/10.5194/acp-24-6305-2024, 2024
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Applying factor analysis techniques to H-NMR spectra, we present the organic aerosol (OA) source apportionment of PM1 samples collected in parallel at two Antarctic stations, namely Signy and Halley, allowing investigation of aerosol–climate interactions in an unperturbed atmosphere. Our results show remarkable differences between pelagic (open-ocean) and sympagic (sea-ice-influenced) air masses and indicate that various sources and processes are controlling Antarctic aerosols.
Jianghao Li, Alastair C. Lewis, Jim R. Hopkins, Stephen J. Andrews, Tim Murrells, Neil Passant, Ben Richmond, Siqi Hou, William J. Bloss, Roy M. Harrison, and Zongbo Shi
Atmos. Chem. Phys., 24, 6219–6231, https://doi.org/10.5194/acp-24-6219-2024, https://doi.org/10.5194/acp-24-6219-2024, 2024
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A summertime ozone event at an urban site in Birmingham is sensitive to volatile organic compounds (VOCs) – particularly those of oxygenated VOCs. The roles of anthropogenic VOC sources in urban ozone chemistry are examined by integrating the 1990–2019 national atmospheric emission inventory into model scenarios. Road transport remains the most powerful means of further reducing ozone in this case study, but the benefits may be offset if solvent emissions of VOCs continue to increase.
Santeri Tuovinen, Janne Lampilahti, Veli-Matti Kerminen, and Markku Kulmala
Aerosol Research, 2, 93–105, https://doi.org/10.5194/ar-2-93-2024, https://doi.org/10.5194/ar-2-93-2024, 2024
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Atmospheric intermediate ions can be used to study atmospheric new particle formation (NPF). Here we aimed to find the optimal ion diameter for this purpose on a local scale. To fulfill our aim, we used ion size number distribution data from the SMEAR II measurement station, Hyytiälä, Finland. We found that concentrations of ions between 2.0–2.3 nm are the best suited for characterization of local intermediate ion formation and could be used to detect and evaluate the strength of local NPF.
Liine Heikkinen, Daniel G. Partridge, Sara Blichner, Wei Huang, Rahul Ranjan, Paul Bowen, Emanuele Tovazzi, Tuukka Petäjä, Claudia Mohr, and Ilona Riipinen
Atmos. Chem. Phys., 24, 5117–5147, https://doi.org/10.5194/acp-24-5117-2024, https://doi.org/10.5194/acp-24-5117-2024, 2024
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The organic vapor condensation with water vapor (co-condensation) in rising air below clouds is modeled in this work over the boreal forest because the forest air is rich in organic vapors. We show that the number of cloud droplets can increase by 20 % if considering co-condensation. The enhancements are even larger if the air contains many small, naturally produced aerosol particles. Such conditions are most frequently met in spring in the boreal forest.
Bjorn Stevens, Stefan Adami, Tariq Ali, Hartwig Anzt, Zafer Aslan, Sabine Attinger, Jaana Bäck, Johanna Baehr, Peter Bauer, Natacha Bernier, Bob Bishop, Hendryk Bockelmann, Sandrine Bony, Guy Brasseur, David N. Bresch, Sean Breyer, Gilbert Brunet, Pier Luigi Buttigieg, Junji Cao, Christelle Castet, Yafang Cheng, Ayantika Dey Choudhury, Deborah Coen, Susanne Crewell, Atish Dabholkar, Qing Dai, Francisco Doblas-Reyes, Dale Durran, Ayoub El Gaidi, Charlie Ewen, Eleftheria Exarchou, Veronika Eyring, Florencia Falkinhoff, David Farrell, Piers M. Forster, Ariane Frassoni, Claudia Frauen, Oliver Fuhrer, Shahzad Gani, Edwin Gerber, Debra Goldfarb, Jens Grieger, Nicolas Gruber, Wilco Hazeleger, Rolf Herken, Chris Hewitt, Torsten Hoefler, Huang-Hsiung Hsu, Daniela Jacob, Alexandra Jahn, Christian Jakob, Thomas Jung, Christopher Kadow, In-Sik Kang, Sarah Kang, Karthik Kashinath, Katharina Kleinen-von Königslöw, Daniel Klocke, Uta Kloenne, Milan Klöwer, Chihiro Kodama, Stefan Kollet, Tobias Kölling, Jenni Kontkanen, Steve Kopp, Michal Koran, Markku Kulmala, Hanna Lappalainen, Fakhria Latifi, Bryan Lawrence, June Yi Lee, Quentin Lejeun, Christian Lessig, Chao Li, Thomas Lippert, Jürg Luterbacher, Pekka Manninen, Jochem Marotzke, Satoshi Matsouoka, Charlotte Merchant, Peter Messmer, Gero Michel, Kristel Michielsen, Tomoki Miyakawa, Jens Müller, Ramsha Munir, Sandeep Narayanasetti, Ousmane Ndiaye, Carlos Nobre, Achim Oberg, Riko Oki, Tuba Özkan-Haller, Tim Palmer, Stan Posey, Andreas Prein, Odessa Primus, Mike Pritchard, Julie Pullen, Dian Putrasahan, Johannes Quaas, Krishnan Raghavan, Venkatachalam Ramaswamy, Markus Rapp, Florian Rauser, Markus Reichstein, Aromar Revi, Sonakshi Saluja, Masaki Satoh, Vera Schemann, Sebastian Schemm, Christina Schnadt Poberaj, Thomas Schulthess, Cath Senior, Jagadish Shukla, Manmeet Singh, Julia Slingo, Adam Sobel, Silvina Solman, Jenna Spitzer, Philip Stier, Thomas Stocker, Sarah Strock, Hang Su, Petteri Taalas, John Taylor, Susann Tegtmeier, Georg Teutsch, Adrian Tompkins, Uwe Ulbrich, Pier-Luigi Vidale, Chien-Ming Wu, Hao Xu, Najibullah Zaki, Laure Zanna, Tianjun Zhou, and Florian Ziemen
Earth Syst. Sci. Data, 16, 2113–2122, https://doi.org/10.5194/essd-16-2113-2024, https://doi.org/10.5194/essd-16-2113-2024, 2024
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To manage Earth in the Anthropocene, new tools, new institutions, and new forms of international cooperation will be required. Earth Virtualization Engines is proposed as an international federation of centers of excellence to empower all people to respond to the immense and urgent challenges posed by climate change.
Heidi Hellén, Rostislav Kouznetsov, Kaisa Kraft, Jukka Seppälä, Mika Vestenius, Jukka-Pekka Jalkanen, Lauri Laakso, and Hannele Hakola
Atmos. Chem. Phys., 24, 4717–4731, https://doi.org/10.5194/acp-24-4717-2024, https://doi.org/10.5194/acp-24-4717-2024, 2024
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Mixing ratios of C2-C5 NMHCs and methanethiol were measured on an island in the Baltic Sea using an in situ gas chromatograph. Shipping emissions were found to be an important source of ethene, ethyne, propene, and benzene. High summertime mixing ratios of methanethiol and dependence of mixing ratios on seawater temperature and height indicated the biogenic origin to possibly be phytoplankton or macroalgae. These emissions may have a strong impact on SO2 production and new particle formation.
Clément Bouvier, Daan van den Broek, Madeleine Ekblom, and Victoria A. Sinclair
Geosci. Model Dev., 17, 2961–2986, https://doi.org/10.5194/gmd-17-2961-2024, https://doi.org/10.5194/gmd-17-2961-2024, 2024
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An analytical initial background state has been developed for moist baroclinic wave simulation on an aquaplanet and implemented into OpenIFS. Seven parameters can be controlled, which are used to generate the background states and the development of baroclinic waves. The meteorological and numerical stability has been assessed. Resulting baroclinic waves have proven to be realistic and sensitive to the jet's width.
Christoffer Hallgren, Jeanie A. Aird, Stefan Ivanell, Heiner Körnich, Ville Vakkari, Rebecca J. Barthelmie, Sara C. Pryor, and Erik Sahlée
Wind Energ. Sci., 9, 821–840, https://doi.org/10.5194/wes-9-821-2024, https://doi.org/10.5194/wes-9-821-2024, 2024
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Knowing the wind speed across the rotor of a wind turbine is key in making good predictions of the power production. However, models struggle to capture both the speed and the shape of the wind profile. Using machine learning methods based on the model data, we show that the predictions can be improved drastically. The work focuses on three coastal sites, spread over the Northern Hemisphere (the Baltic Sea, the North Sea, and the US Atlantic coast) with similar results for all sites.
Gabriela R. Unfer, Luiz A. T. Machado, Paulo Artaxo, Marco A. Franco, Leslie A. Kremper, Mira L. Pöhlker, Ulrich Pöschl, and Christopher Pöhlker
Atmos. Chem. Phys., 24, 3869–3882, https://doi.org/10.5194/acp-24-3869-2024, https://doi.org/10.5194/acp-24-3869-2024, 2024
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Amazonian aerosols and their interactions with precipitation were studied by understanding them in a 3D space based on three parameters that characterize the concentration and size distribution of aerosols. The results showed characteristic arrangements regarding seasonal and diurnal cycles, as well as when interacting with precipitation. The use of this 3D space appears to be a promising tool for aerosol population analysis and for model validation and parameterization.
Markku Kulmala, Diego Aliaga, Santeri Tuovinen, Runlong Cai, Heikki Junninen, Chao Yan, Federico Bianchi, Yafang Cheng, Aijun Ding, Douglas R. Worsnop, Tuukka Petäjä, Katrianne Lehtipalo, Pauli Paasonen, and Veli-Matti Kerminen
Aerosol Research, 2, 49–58, https://doi.org/10.5194/ar-2-49-2024, https://doi.org/10.5194/ar-2-49-2024, 2024
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Atmospheric new particle formation (NPF), together with secondary production of particulate matter in the atmosphere, dominates aerosol particle number concentrations and submicron particle mass loads in many environments globally. In this opinion paper, we describe the paradigm shift to understand NPF in a continuous way instead of using traditional binary event–non-event analysis.
Anil Kumar Mandariya, Ajit Ahlawat, Mohammed Haneef, Nisar Ali Baig, Kanan Patel, Joshua Apte, Lea Hildebrandt Ruiz, Alfred Wiedensohler, and Gazala Habib
Atmos. Chem. Phys., 24, 3627–3647, https://doi.org/10.5194/acp-24-3627-2024, https://doi.org/10.5194/acp-24-3627-2024, 2024
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The current study explores the temporal variation of size-selected particle hygroscopicity in Delhi for the first time. Here, we report that the high volume fraction contribution of ammonium chloride to aerosol governs the high aerosol hygroscopicity and associated liquid water content based on the experimental data. The episodically high ammonium chloride present in Delhi's atmosphere could lead to haze and fog formation under high relative humidity in the region.
Jian Zhao, Valter Mickwitz, Yuanyuan Luo, Ella Häkkinen, Frans Graeffe, Jiangyi Zhang, Hilkka Timonen, Manjula Canagaratna, Jordan E. Krechmer, Qi Zhang, Markku Kulmala, Juha Kangasluoma, Douglas Worsnop, and Mikael Ehn
Atmos. Meas. Tech., 17, 1527–1543, https://doi.org/10.5194/amt-17-1527-2024, https://doi.org/10.5194/amt-17-1527-2024, 2024
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Organic aerosol constitutes a significant portion of atmospheric fine particles but is less characterized due to its vast number of constituents. Recently, we developed a system for online measurements of particle-phase highly oxygenated organic molecules (HOMs). In this work, we systematically characterized the system, developed a new unit to enhance its performance, and demonstrated the essential role of thermograms in inferring volatility and quantifying HOMs in organic aerosols.
C. Isabel Moreno, Radovan Krejci, Jean-Luc Jaffrezo, Gaëlle Uzu, Andrés Alastuey, Marcos F. Andrade, Valeria Mardóñez, Alkuin Maximilian Koenig, Diego Aliaga, Claudia Mohr, Laura Ticona, Fernando Velarde, Luis Blacutt, Ricardo Forno, David N. Whiteman, Alfred Wiedensohler, Patrick Ginot, and Paolo Laj
Atmos. Chem. Phys., 24, 2837–2860, https://doi.org/10.5194/acp-24-2837-2024, https://doi.org/10.5194/acp-24-2837-2024, 2024
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Aerosol chemical composition (ions, sugars, carbonaceous matter) from 2011 to 2020 was studied at Mt. Chacaltaya (5380 m a.s.l., Bolivian Andes). Minimum concentrations occur in the rainy season with maxima in the dry and transition seasons. The origins of the aerosol are located in a radius of hundreds of kilometers: nearby urban and rural areas, natural biogenic emissions, vegetation burning from Amazonia and Chaco, Pacific Ocean emissions, soil dust, and Peruvian volcanism.
Shiyi Lai, Ximeng Qi, Xin Huang, Sijia Lou, Xuguang Chi, Liangduo Chen, Chong Liu, Yuliang Liu, Chao Yan, Mengmeng Li, Tengyu Liu, Wei Nie, Veli-Matti Kerminen, Tuukka Petäjä, Markku Kulmala, and Aijun Ding
Atmos. Chem. Phys., 24, 2535–2553, https://doi.org/10.5194/acp-24-2535-2024, https://doi.org/10.5194/acp-24-2535-2024, 2024
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By combining in situ measurements and chemical transport modeling, this study investigates new particle formation (NPF) on the southeastern Tibetan Plateau. We found that the NPF was driven by the presence of biogenic gases and the transport of anthropogenic precursors. The NPF was vertically heterogeneous and shaped by the vertical mixing. This study highlights the importance of anthropogenic–biogenic interactions and meteorological dynamics in NPF in this climate-sensitive region.
Andrea Cuesta-Mosquera, Kristina Glojek, Griša Močnik, Luka Drinovec, Asta Gregorič, Martin Rigler, Matej Ogrin, Baseerat Romshoo, Kay Weinhold, Maik Merkel, Dominik van Pinxteren, Hartmut Herrmann, Alfred Wiedensohler, Mira Pöhlker, and Thomas Müller
Atmos. Chem. Phys., 24, 2583–2605, https://doi.org/10.5194/acp-24-2583-2024, https://doi.org/10.5194/acp-24-2583-2024, 2024
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This study evaluated the air pollution and climate impacts of residential-wood-burning particle emissions from a rural European site. The authors investigate the optical and physical properties that connect the aerosol emissions with climate by evaluating atmospheric radiative impacts via simple-forcing calculations. The study contributes to reducing the lack of information on the understanding of the optical properties of air pollution from anthropogenic sources.
Jing Cai, Juha Sulo, Yifang Gu, Sebastian Holm, Runlong Cai, Steven Thomas, Almuth Neuberger, Fredrik Mattsson, Marco Paglione, Stefano Decesari, Matteo Rinaldi, Rujing Yin, Diego Aliaga, Wei Huang, Yuanyuan Li, Yvette Gramlich, Giancarlo Ciarelli, Lauriane Quéléver, Nina Sarnela, Katrianne Lehtipalo, Nora Zannoni, Cheng Wu, Wei Nie, Juha Kangasluoma, Claudia Mohr, Markku Kulmala, Qiaozhi Zha, Dominik Stolzenburg, and Federico Bianchi
Atmos. Chem. Phys., 24, 2423–2441, https://doi.org/10.5194/acp-24-2423-2024, https://doi.org/10.5194/acp-24-2423-2024, 2024
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By combining field measurements, simulations and recent chamber experiments, we investigate new particle formation (NPF) and growth in the Po Valley, where both haze and frequent NPF occur. Our results show that sulfuric acid, ammonia and amines are the dominant NPF precursors there. A high NPF rate and a lower condensation sink lead to a greater survival probability for newly formed particles, highlighting the importance of gas-to-particle conversion for aerosol concentrations.
Anton Rusanen, Anton Björklund, Manousos I. Manousakas, Jianhui Jiang, Markku T. Kulmala, Kai Puolamäki, and Kaspar R. Daellenbach
Atmos. Meas. Tech., 17, 1251–1277, https://doi.org/10.5194/amt-17-1251-2024, https://doi.org/10.5194/amt-17-1251-2024, 2024
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We present a Bayesian non-negative matrix factorization model that performs better on our test datasets than currently widely used models. Its advantages are better use of time information and providing a direct error estimation. We believe this could lead to better estimates of emission sources from measurements.
Juha Sulo, Joonas Enroth, Aki Pajunoja, Joonas Vanhanen, Katrianne Lehtipalo, Tuukka Petäjä, and Markku Kulmala
Aerosol Research, 2, 13–20, https://doi.org/10.5194/ar-2-13-2024, https://doi.org/10.5194/ar-2-13-2024, 2024
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We present a novel version of an aerosol number size distribution instrument, showcasing its capability to measure particle number concentration and particle number size distribution between 1 and 12 nm. Our results show that the instrument agrees well with existing instrumentation and allows for both the accurate measurement of the smallest particles and overlap with more conventional aerosol number size distribution instruments.
Dominic Heslin-Rees, Peter Tunved, Johan Ström, Roxana Cremer, Paul Zieger, Ilona Riipinen, Annica M. L. Ekman, Konstantinos Eleftheriadis, and Radovan Krejci
Atmos. Chem. Phys., 24, 2059–2075, https://doi.org/10.5194/acp-24-2059-2024, https://doi.org/10.5194/acp-24-2059-2024, 2024
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Light-absorbing atmospheric particles (e.g. black carbon – BC) exert a warming effect on the Arctic climate. We show that the amount of particle light absorption decreased from 2002 to 2023. We conclude that in addition to reductions in emissions of BC, wet removal plays a role in the long-term reduction of BC in the Arctic, given the increase in surface precipitation experienced by air masses arriving at the site. The potential impact of biomass burning events is shown to have increased.
Ying Zhang, Duzitian Li, Xu-Cheng He, Wei Nie, Chenjuan Deng, Runlong Cai, Yuliang Liu, Yishuo Guo, Chong Liu, Yiran Li, Liangduo Chen, Yuanyuan Li, Chenjie Hua, Tingyu Liu, Zongcheng Wang, Jiali Xie, Lei Wang, Tuukka Petäjä, Federico Bianchi, Ximeng Qi, Xuguang Chi, Pauli Paasonen, Yongchun Liu, Chao Yan, Jingkun Jiang, Aijun Ding, and Markku Kulmala
Atmos. Chem. Phys., 24, 1873–1893, https://doi.org/10.5194/acp-24-1873-2024, https://doi.org/10.5194/acp-24-1873-2024, 2024
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This study conducts a long-term observation of gaseous iodine oxoacids in two Chinese megacities, revealing their ubiquitous presence with peak concentrations (up to 0.1 pptv) in summer. Our analysis suggests a mix of terrestrial and marine sources for iodine. Additionally, iodic acid is identified as a notable contributor to sub-3 nm particle growth and particle survival probability.
Natalie M. Mahowald, Longlei Li, Julius Vira, Marje Prank, Douglas S. Hamilton, Hitoshi Matsui, Ron L. Miller, Louis Lu, Ezgi Akyuz, Daphne Meidan, Peter Hess, Heikki Lihavainen, Christine Wiedinmyer, Jenny Hand, Maria Grazia Alaimo, Célia Alves, Andres Alastuey, Paulo Artaxo, Africa Barreto, Francisco Barraza, Silvia Becagli, Giulia Calzolai, Shankarararman Chellam, Ying Chen, Patrick Chuang, David D. Cohen, Cristina Colombi, Evangelia Diapouli, Gaetano Dongarra, Konstantinos Eleftheriadis, Corinne Galy-Lacaux, Cassandra Gaston, Dario Gomez, Yenny González Ramos, Hannele Hakola, Roy M. Harrison, Chris Heyes, Barak Herut, Philip Hopke, Christoph Hüglin, Maria Kanakidou, Zsofia Kertesz, Zbiginiw Klimont, Katriina Kyllönen, Fabrice Lambert, Xiaohong Liu, Remi Losno, Franco Lucarelli, Willy Maenhaut, Beatrice Marticorena, Randall V. Martin, Nikolaos Mihalopoulos, Yasser Morera-Gomez, Adina Paytan, Joseph Prospero, Sergio Rodríguez, Patricia Smichowski, Daniela Varrica, Brenna Walsh, Crystal Weagle, and Xi Zhao
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2024-1, https://doi.org/10.5194/essd-2024-1, 2024
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Aerosol particles can interact with incoming solar radiation and outgoing long wave radiation, change cloud properties, affect photochemistry, impact surface air quality, and when deposited impact surface albedo of snow and ice, and modulate carbon dioxide uptake by the land and ocean. Here we present a new compilation of aerosol observations including composition, a methodology for comparing the datasets to model output, and show the implications of these results using one model.
Viet Le, Hannah Lobo, Ewan J. O'Connor, and Ville Vakkari
Atmos. Meas. Tech., 17, 921–941, https://doi.org/10.5194/amt-17-921-2024, https://doi.org/10.5194/amt-17-921-2024, 2024
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This study offers a long-term overview of aerosol particle depolarization ratio at the wavelength of 1565 nm obtained from vertical profiling measurements by Halo Doppler lidars during 4 years at four different locations across Finland. Our observations support the long-term usage of Halo Doppler lidar depolarization ratio such as the detection of aerosols that may pose a safety risk for aviation. Long-range Saharan dust transport and pollen transport are also showcased here.
Arto Heitto, Cheng Wu, Diego Aliaga, Luis Blacutt, Xuemeng Chen, Yvette Gramlich, Liine Heikkinen, Wei Huang, Radovan Krejci, Paolo Laj, Isabel Moreno, Karine Sellegri, Fernando Velarde, Kay Weinhold, Alfred Wiedensohler, Qiaozhi Zha, Federico Bianchi, Marcos Andrade, Kari E. J. Lehtinen, Claudia Mohr, and Taina Yli-Juuti
Atmos. Chem. Phys., 24, 1315–1328, https://doi.org/10.5194/acp-24-1315-2024, https://doi.org/10.5194/acp-24-1315-2024, 2024
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Particle growth at the Chacaltaya station in Bolivia was simulated based on measured vapor concentrations and ambient conditions. Major contributors to the simulated growth were low-volatility organic compounds (LVOCs). Also, sulfuric acid had major role when volcanic activity was occurring in the area. This study provides insight on nanoparticle growth at this high-altitude Southern Hemispheric site and hence contributes to building knowledge of early growth of atmospheric particles.
Giancarlo Ciarelli, Sara Tahvonen, Arineh Cholakian, Manuel Bettineschi, Bruno Vitali, Tuukka Petäjä, and Federico Bianchi
Geosci. Model Dev., 17, 545–565, https://doi.org/10.5194/gmd-17-545-2024, https://doi.org/10.5194/gmd-17-545-2024, 2024
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The terrestrial ecosystem releases large quantities of biogenic gases in the Earth's Atmosphere. These gases can effectively be converted into so-called biogenic aerosol particles and, eventually, affect the Earth's climate. Climate prediction varies greatly depending on how these processes are represented in model simulations. In this study, we present a detailed model evaluation analysis aimed at understanding the main source of uncertainty in predicting the formation of biogenic aerosols.
Andreas Aktypis, Christos Kaltsonoudis, David Patoulias, Panayiotis Kalkavouras, Angeliki Matrali, Christina N. Vasilakopoulou, Evangelia Kostenidou, Kalliopi Florou, Nikos Kalivitis, Aikaterini Bougiatioti, Konstantinos Eleftheriadis, Stergios Vratolis, Maria I. Gini, Athanasios Kouras, Constantini Samara, Mihalis Lazaridis, Sofia-Eirini Chatoutsidou, Nikolaos Mihalopoulos, and Spyros N. Pandis
Atmos. Chem. Phys., 24, 65–84, https://doi.org/10.5194/acp-24-65-2024, https://doi.org/10.5194/acp-24-65-2024, 2024
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Extensive continuous particle number size distribution measurements took place during two summers (2020 and 2021) at 11 sites in Greece for the investigation of the frequency and the spatial extent of new particle formation. The frequency during summer varied from close to zero in southwestern Greece to more than 60 % in the northern, central, and eastern regions. The spatial variability can be explained by the proximity of the sites to coal-fired power plants and agricultural areas.
Juan Andrés Casquero-Vera, Daniel Pérez-Ramírez, Hassan Lyamani, Fernando Rejano, Andrea Casans, Gloria Titos, Francisco José Olmo, Lubna Dada, Simo Hakala, Tareq Hussein, Katrianne Lehtipalo, Pauli Paasonen, Antti Hyvärinen, Noemí Pérez, Xavier Querol, Sergio Rodríguez, Nikos Kalivitis, Yenny González, Mansour A. Alghamdi, Veli-Matti Kerminen, Andrés Alastuey, Tuukka Petäjä, and Lucas Alados-Arboledas
Atmos. Chem. Phys., 23, 15795–15814, https://doi.org/10.5194/acp-23-15795-2023, https://doi.org/10.5194/acp-23-15795-2023, 2023
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Here we present the first study of the effect of mineral dust on the inhibition/promotion of new particle formation (NPF) events in different dust-influenced areas. Unexpectedly, we show that the occurrence of NPF events is highly frequent during mineral dust outbreaks, occurring even during extreme dust outbreaks. We also show that the occurrence of NPF events during mineral dust outbreaks significantly affects the potential cloud condensation nuclei budget.
Diego Aliaga, Santeri Tuovinen, Tinghan Zhang, Janne Lampilahti, Xinyang Li, Lauri Ahonen, Tom Kokkonen, Tuomo Nieminen, Simo Hakala, Pauli Paasonen, Federico Bianchi, Doug Worsnop, Veli-Matti Kerminen, and Markku Kulmala
Aerosol Research, 1, 81–92, https://doi.org/10.5194/ar-1-81-2023, https://doi.org/10.5194/ar-1-81-2023, 2023
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We introduce a novel method for evaluating days when small particles are formed in the atmosphere. Instead of the traditional binary division between event and non-event days, our method, known as "nano ranking analysis", provides a continuous, non-categorical metric for each day. By utilizing data from Hyytiälä, Finland, we show that our approach effectively quantifies these events. This innovative method paves the way for a deeper understanding of the factors influencing particle formation.
Markku Kulmala, Anna Lintunen, Hanna Lappalainen, Annele Virtanen, Chao Yan, Ekaterina Ezhova, Tuomo Nieminen, Ilona Riipinen, Risto Makkonen, Johanna Tamminen, Anu-Maija Sundström, Antti Arola, Armin Hansel, Kari Lehtinen, Timo Vesala, Tuukka Petäjä, Jaana Bäck, Tom Kokkonen, and Veli-Matti Kerminen
Atmos. Chem. Phys., 23, 14949–14971, https://doi.org/10.5194/acp-23-14949-2023, https://doi.org/10.5194/acp-23-14949-2023, 2023
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To be able to meet global grand challenges, we need comprehensive open data with proper metadata. In this opinion paper, we describe the SMEAR (Station for Measuring Earth surface – Atmosphere Relations) concept and include several examples (cases), such as new particle formation and growth, feedback loops and the effect of COVID-19, and what has been learned from these investigations. The future needs and the potential of comprehensive observations of the environment are summarized.
Putian Zhou, Zhengyao Lu, Jukka-Pekka Keskinen, Qiong Zhang, Juha Lento, Jianpu Bian, Twan van Noije, Philippe Le Sager, Veli-Matti Kerminen, Markku Kulmala, Michael Boy, and Risto Makkonen
Clim. Past, 19, 2445–2462, https://doi.org/10.5194/cp-19-2445-2023, https://doi.org/10.5194/cp-19-2445-2023, 2023
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A Green Sahara with enhanced rainfall and larger vegetation cover existed in northern Africa about 6000 years ago. Biosphere–atmosphere interactions are found to be critical to explaining this wet period. Based on modeled vegetation reconstruction data, we simulated dust emissions and aerosol formation, which are key factors in biosphere–atmosphere interactions. Our results also provide a benchmark of aerosol climatology for future paleo-climate simulation experiments.
Xiaoxiao Li, Yijing Chen, Yuyang Li, Runlong Cai, Yiran Li, Chenjuan Deng, Jin Wu, Chao Yan, Hairong Cheng, Yongchun Liu, Markku Kulmala, Jiming Hao, James N. Smith, and Jingkun Jiang
Atmos. Chem. Phys., 23, 14801–14812, https://doi.org/10.5194/acp-23-14801-2023, https://doi.org/10.5194/acp-23-14801-2023, 2023
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Near-continuous measurements show the composition, sources, and seasonal variations of ultrafine particles (UFPs) in urban Beijing. Vehicle and cooking emissions and new particle formation are the main sources of UFPs, and aqueous/heterogeneous processes increase UFP mode diameters. UFPs are the highest in winter due to the highest primary particle emission rates and new particle formation rates, and CHO fractions are the highest in summer due to the strongest photooxidation.
Jiyeon Park, Hyojin Kang, Yeontae Gim, Eunho Jang, Ki-Tae Park, Sangjong Park, Chang Hoon Jung, Darius Ceburnis, Colin O'Dowd, and Young Jun Yoon
Atmos. Chem. Phys., 23, 13625–13646, https://doi.org/10.5194/acp-23-13625-2023, https://doi.org/10.5194/acp-23-13625-2023, 2023
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We measured the number size distribution of 2.5–300 nm particles and cloud condensation nuclei (CCN) number concentrations at King Sejong Station on the Antarctic Peninsula continuously from 1 January to 31 December 2018. During the pristine and clean periods, 97 new particle formation (NPF) events were detected. For 83 of these, CCN concentrations increased by 2 %–268 % (median 44 %) following 1 to 36 h (median 8 h) after NPF events.
Magdalena Okuljar, Olga Garmash, Miska Olin, Joni Kalliokoski, Hilkka Timonen, Jarkko V. Niemi, Pauli Paasonen, Jenni Kontkanen, Yanjun Zhang, Heidi Hellén, Heino Kuuluvainen, Minna Aurela, Hanna E. Manninen, Mikko Sipilä, Topi Rönkkö, Tuukka Petäjä, Markku Kulmala, Miikka Dal Maso, and Mikael Ehn
Atmos. Chem. Phys., 23, 12965–12983, https://doi.org/10.5194/acp-23-12965-2023, https://doi.org/10.5194/acp-23-12965-2023, 2023
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Highly oxygenated organic molecules (HOMs) form secondary organic aerosol that affects air quality and health. In this study, we demonstrate that in a moderately polluted city with abundant vegetation, the composition of HOMs is largely controlled by the effect of NOx on the biogenic volatile organic compound oxidation. Comparing the results from two nearby stations, we show that HOM composition and formation pathways can change considerably within small distances in urban environments.
Christoffer Hallgren, Heiner Körnich, Stefan Ivanell, Ville Vakkari, and Erik Sahlée
Wind Energ. Sci. Discuss., https://doi.org/10.5194/wes-2023-129, https://doi.org/10.5194/wes-2023-129, 2023
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Sometimes, the wind changes direction between the bottom and top part of a wind turbine. This affects both the power production and the loads on the turbine. In this study, a climatology of pronounced changes in wind direction across the rotor is created, focusing on Scandinavia. The weather conditions responsible for these changes in wind direction are investigated and the climatology is compared to measurements from two coastal sites, indicating an underestimation by the climatology.
Xu-Cheng He, Jiali Shen, Siddharth Iyer, Paxton Juuti, Jiangyi Zhang, Mrisha Koirala, Mikko M. Kytökari, Douglas R. Worsnop, Matti Rissanen, Markku Kulmala, Norbert M. Maier, Jyri Mikkilä, Mikko Sipilä, and Juha Kangasluoma
Atmos. Meas. Tech., 16, 4461–4487, https://doi.org/10.5194/amt-16-4461-2023, https://doi.org/10.5194/amt-16-4461-2023, 2023
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In this study, the upgraded multi-scheme chemical ionisation inlet 2 is presented. Sulfuric acid, hypoiodous acid, iodine, sulfur dioxide, and hydroperoxyl radicals are calibrated, and the improved ion optics allow us to detect sulfuric acid and iodine-containing molecules at as low as a few parts per quadrillion by volume. Additionally, we confirm the reliable detection of iodic acid using both the nitrate and bromide chemical ionisation methods under atmospherically relevant conditions.
Mark Joseph Campmier, Jonathan Gingrich, Saumya Singh, Nisar Baig, Shahzad Gani, Adithi Upadhya, Pratyush Agrawal, Meenakshi Kushwaha, Harsh Raj Mishra, Ajay Pillarisetti, Sreekanth Vakacherla, Ravi Kant Pathak, and Joshua S. Apte
Atmos. Meas. Tech., 16, 4357–4374, https://doi.org/10.5194/amt-16-4357-2023, https://doi.org/10.5194/amt-16-4357-2023, 2023
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We studied a low-cost air pollution sensor called PurpleAir PA-II in three different locations in India (Delhi, Hamirpur, and Bangalore) to characterize its performance. We compared its signal to more expensive reference sensors and found that the PurpleAir sensor was precise but inaccurate without calibration. We created a custom calibration equation for each location, which improved the accuracy of the PurpleAir sensor, and found that calibrations should be adjusted for different seasons.
Valeria Mardoñez, Marco Pandolfi, Lucille Joanna S. Borlaza, Jean-Luc Jaffrezo, Andrés Alastuey, Jean-Luc Besombes, Isabel Moreno R., Noemi Perez, Griša Močnik, Patrick Ginot, Radovan Krejci, Vladislav Chrastny, Alfred Wiedensohler, Paolo Laj, Marcos Andrade, and Gaëlle Uzu
Atmos. Chem. Phys., 23, 10325–10347, https://doi.org/10.5194/acp-23-10325-2023, https://doi.org/10.5194/acp-23-10325-2023, 2023
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La Paz and El Alto are two fast-growing, high-altitude Bolivian cities forming the second-largest metropolitan area in the country. The sources of particulate matter (PM) in this conurbation were not previously investigated. This study identified 11 main sources of PM, of which dust and vehicular emissions stand out as the main ones. The influence of regional biomass combustion and local waste combustion was also observed, with the latter being a major source of hazardous compounds.
Jean-Philippe Putaud, Enrico Pisoni, Alexander Mangold, Christoph Hueglin, Jean Sciare, Michael Pikridas, Chrysanthos Savvides, Jakub Ondracek, Saliou Mbengue, Alfred Wiedensohler, Kay Weinhold, Maik Merkel, Laurent Poulain, Dominik van Pinxteren, Hartmut Herrmann, Andreas Massling, Claus Nordstroem, Andrés Alastuey, Cristina Reche, Noemí Pérez, Sonia Castillo, Mar Sorribas, Jose Antonio Adame, Tuukka Petaja, Katrianne Lehtipalo, Jarkko Niemi, Véronique Riffault, Joel F. de Brito, Augustin Colette, Olivier Favez, Jean-Eudes Petit, Valérie Gros, Maria I. Gini, Stergios Vratolis, Konstantinos Eleftheriadis, Evangelia Diapouli, Hugo Denier van der Gon, Karl Espen Yttri, and Wenche Aas
Atmos. Chem. Phys., 23, 10145–10161, https://doi.org/10.5194/acp-23-10145-2023, https://doi.org/10.5194/acp-23-10145-2023, 2023
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Many European people are still exposed to levels of air pollution that can affect their health. COVID-19 lockdowns in 2020 were used to assess the impact of the reduction in human mobility on air pollution across Europe by comparing measurement data with values that would be expected if no lockdown had occurred. We show that lockdown measures did not lead to consistent decreases in the concentrations of fine particulate matter suspended in the air, and we investigate why.
Mária Lbadaoui-Darvas, Ari Laaksonen, and Athanasios Nenes
Atmos. Chem. Phys., 23, 10057–10074, https://doi.org/10.5194/acp-23-10057-2023, https://doi.org/10.5194/acp-23-10057-2023, 2023
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Heterogeneous ice nucleation is the main ice formation mechanism in clouds. The mechanism of different freezing modes is to date unknown, which results in large model biases. Experiments do not allow for direct observation of ice nucleation at its native resolution. This work uses first principles molecular simulations to determine the mechanism of the least-understood ice nucleation mode and link it to adsorption through a novel modeling framework that unites ice and droplet formation.
Xurong Wang, Qiaoqiao Wang, Maria Prass, Christopher Pöhlker, Daniel Moran-Zuloaga, Paulo Artaxo, Jianwei Gu, Ning Yang, Xiajie Yang, Jiangchuan Tao, Juan Hong, Nan Ma, Yafang Cheng, Hang Su, and Meinrat O. Andreae
Atmos. Chem. Phys., 23, 9993–10014, https://doi.org/10.5194/acp-23-9993-2023, https://doi.org/10.5194/acp-23-9993-2023, 2023
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In this work, with an optimized particle mass size distribution, we captured observed aerosol optical depth (AOD) and coarse aerosol concentrations over source and/or receptor regions well, demonstrating good performance in simulating export of African dust toward the Amazon Basin. In addition to factors controlling the transatlantic transport of African dust, the study investigated the impact of African dust over the Amazon Basin, including the nutrient inputs associated with dust deposition.
Simo Hakala, Ville Vakkari, Heikki Lihavainen, Antti-Pekka Hyvärinen, Kimmo Neitola, Jenni Kontkanen, Veli-Matti Kerminen, Markku Kulmala, Tuukka Petäjä, Tareq Hussein, Mamdouh I. Khoder, Mansour A. Alghamdi, and Pauli Paasonen
Atmos. Chem. Phys., 23, 9287–9321, https://doi.org/10.5194/acp-23-9287-2023, https://doi.org/10.5194/acp-23-9287-2023, 2023
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Things are not always as they first seem in ambient aerosol measurements. Observations of decreasing particle sizes are often interpreted as resulting from particle evaporation. We show that such observations can counterintuitively be explained by particles that are constantly growing in size. This requires one to account for the previous movements of the observed air. Our explanation implies a larger number of larger particles, meaning more significant effects of aerosols on climate and health.
Dimitri Castarède, Zoé Brasseur, Yusheng Wu, Zamin A. Kanji, Markus Hartmann, Lauri Ahonen, Merete Bilde, Markku Kulmala, Tuukka Petäjä, Jan B. C. Pettersson, Berko Sierau, Olaf Stetzer, Frank Stratmann, Birgitta Svenningsson, Erik Swietlicki, Quynh Thu Nguyen, Jonathan Duplissy, and Erik S. Thomson
Atmos. Meas. Tech., 16, 3881–3899, https://doi.org/10.5194/amt-16-3881-2023, https://doi.org/10.5194/amt-16-3881-2023, 2023
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Clouds play a key role in Earth’s climate by influencing the surface energy budget. Certain types of atmospheric aerosols, called ice-nucleating particles (INPs), induce the formation of ice in clouds and, thus, often initiate precipitation formation. The Portable Ice Nucleation Chamber 2 (PINCii) is a new instrument developed to study ice formation and to conduct ambient measurements of INPs, allowing us to investigate the sources and properties of the atmospheric aerosols that can act as INPs.
Sophie L. Haslett, David M. Bell, Varun Kumar, Jay G. Slowik, Dongyu S. Wang, Suneeti Mishra, Neeraj Rastogi, Atinderpal Singh, Dilip Ganguly, Joel Thornton, Feixue Zheng, Yuanyuan Li, Wei Nie, Yongchun Liu, Wei Ma, Chao Yan, Markku Kulmala, Kaspar R. Daellenbach, David Hadden, Urs Baltensperger, Andre S. H. Prevot, Sachchida N. Tripathi, and Claudia Mohr
Atmos. Chem. Phys., 23, 9023–9036, https://doi.org/10.5194/acp-23-9023-2023, https://doi.org/10.5194/acp-23-9023-2023, 2023
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In Delhi, some aspects of daytime and nighttime atmospheric chemistry are inverted, and parodoxically, vehicle emissions may be limiting other forms of particle production. This is because the nighttime emissions of nitrogen oxide (NO) by traffic and biomass burning prevent some chemical processes that would otherwise create even more particles and worsen the urban haze.
Maria Filioglou, Ari Leskinen, Ville Vakkari, Ewan O'Connor, Minttu Tuononen, Pekko Tuominen, Samuli Laukkanen, Linnea Toiviainen, Annika Saarto, Xiaoxia Shang, Petri Tiitta, and Mika Komppula
Atmos. Chem. Phys., 23, 9009–9021, https://doi.org/10.5194/acp-23-9009-2023, https://doi.org/10.5194/acp-23-9009-2023, 2023
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Pollen impacts climate and public health, and it can be detected in the atmosphere by lidars which measure the linear particle depolarization ratio (PDR), a shape-relevant optical parameter. As aerosols also cause depolarization, surface aerosol and pollen observations were combined with measurements from ground-based lidars operating at different wavelengths to determine the optical properties of birch and pine pollen and quantify their relative contribution to the PDR.
Yuyang Li, Jiewen Shen, Bin Zhao, Runlong Cai, Shuxiao Wang, Yang Gao, Manish Shrivastava, Da Gao, Jun Zheng, Markku Kulmala, and Jingkun Jiang
Atmos. Chem. Phys., 23, 8789–8804, https://doi.org/10.5194/acp-23-8789-2023, https://doi.org/10.5194/acp-23-8789-2023, 2023
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We set up a new parameterization for 1.4 nm particle formation rates from sulfuric acid–dimethylamine (SA–DMA) nucleation, fully including the effects of coagulation scavenging and cluster stability. Incorporating the new parameterization into 3-D chemical transport models, we achieved better consistencies between simulation results and observation data. This new parameterization provides new insights into atmospheric nucleation simulations and its effects on atmospheric pollution or health.
Akriti Masoom, Ilias Fountoulakis, Stelios Kazadzis, Ioannis-Panagiotis Raptis, Anna Kampouri, Basil E. Psiloglou, Dimitra Kouklaki, Kyriakoula Papachristopoulou, Eleni Marinou, Stavros Solomos, Anna Gialitaki, Dimitra Founda, Vasileios Salamalikis, Dimitris Kaskaoutis, Natalia Kouremeti, Nikolaos Mihalopoulos, Vassilis Amiridis, Andreas Kazantzidis, Alexandros Papayannis, Christos S. Zerefos, and Kostas Eleftheratos
Atmos. Chem. Phys., 23, 8487–8514, https://doi.org/10.5194/acp-23-8487-2023, https://doi.org/10.5194/acp-23-8487-2023, 2023
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We analyse the spatial and temporal aerosol spectral optical properties during the extreme wildfires of August 2021 in Greece and assess their effects on air quality and solar radiation quantities related to health, agriculture, and energy. Different aerosol conditions are identified (pure smoke, pure dust, dust–smoke together); the largest impact on solar radiation quantities is found for cases with mixed dust–smoke aerosols. Such situations are expected to occur more frequently in the future.
Guangdong Niu, Ximeng Qi, Liangduo Chen, Lian Xue, Shiyi Lai, Xin Huang, Jiaping Wang, Xuguang Chi, Wei Nie, Veli-Matti Kerminen, Tuukka Petäjä, Markku Kulmala, and Aijun Ding
Atmos. Chem. Phys., 23, 7521–7534, https://doi.org/10.5194/acp-23-7521-2023, https://doi.org/10.5194/acp-23-7521-2023, 2023
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The reported below-cloud wet-scavenging coefficients (BWSCs) are much higher than theoretical data, but the reason remains unclear. Based on long-term observation, we find that air mass changing during rainfall events causes the overestimation of BWSCs. Thus, the discrepancy in BWSCs between observation and theory is not as large as currently believed. To obtain reasonable BWSCs and parameterizations from field observations, the effect of air mass changes needs to be considered.
Jonas Elm, Aladár Czitrovszky, Andreas Held, Annele Virtanen, Astrid Kiendler-Scharr, Benjamin J. Murray, Daniel McCluskey, Daniele Contini, David Broday, Eirini Goudeli, Hilkka Timonen, Joan Rosell-Llompart, Jose L. Castillo, Evangelia Diapouli, Mar Viana, Maria E. Messing, Markku Kulmala, Naděžda Zíková, and Sebastian H. Schmitt
Aerosol Research, 1, 13–16, https://doi.org/10.5194/ar-1-13-2023, https://doi.org/10.5194/ar-1-13-2023, 2023
Victoria A. Sinclair and Jennifer L. Catto
Weather Clim. Dynam., 4, 567–589, https://doi.org/10.5194/wcd-4-567-2023, https://doi.org/10.5194/wcd-4-567-2023, 2023
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We studied the relationship between the strength of mid-latitude cyclones and their precipitation, how this may change in the future, and whether it depends of the type of cyclone. The relationship between cyclone strength and precipitation increases in warmer climates and depends strongly on the type of cyclone. For some cyclone types there is no relation between cyclone strength and precipitation. For all cyclone types, precipitation increases with uniform warming and polar amplification.
Samira Atabakhsh, Laurent Poulain, Gang Chen, Francesco Canonaco, André S. H. Prévôt, Mira Pöhlker, Alfred Wiedensohler, and Hartmut Herrmann
Atmos. Chem. Phys., 23, 6963–6988, https://doi.org/10.5194/acp-23-6963-2023, https://doi.org/10.5194/acp-23-6963-2023, 2023
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The study focuses on the aerosol chemical variations found in the rural-background station of Melpitz based on ACSM and MAAP measurements. Source apportionment on both organic aerosol (OA) and black carbon (eBC) was performed, and source seasonality was also linked to air mass trajectories. Overall, three anthropogenic sources were identified in OA and eBC plus two additional aged OA. Our results demonstrate the influence of transported coal-combustion-related OA even during summer time.
Santeri Tuovinen, Janne Lampilahti, Veli-Matti Kerminen, and Markku Kulmala
EGUsphere, https://doi.org/10.5194/egusphere-2023-1108, https://doi.org/10.5194/egusphere-2023-1108, 2023
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Atmospheric ions can be used to characterize and detect atmospheric new particle formation. In this study we aimed to find the optimal ion diameter for this purpose within a local scale. To fulfill our aim, we used ion size number distribution data from SMEAR II measurement station, Hyytiälä, Finland. We found that negative ions between 2.0–2.3 nm are the best suited for characterization of local NPF, with minimized influence of transported ions.
Chenxi Li, Yuyang Li, Xiaoxiao Li, Runlong Cai, Yaxin Fan, Xiaohui Qiao, Rujing Yin, Chao Yan, Yishuo Guo, Yongchun Liu, Jun Zheng, Veli-Matti Kerminen, Markku Kulmala, Huayun Xiao, and Jingkun Jiang
Atmos. Chem. Phys., 23, 6879–6896, https://doi.org/10.5194/acp-23-6879-2023, https://doi.org/10.5194/acp-23-6879-2023, 2023
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New particle formation and growth in polluted environments are not fully understood despite intensive research. We applied a cluster dynamics–multicomponent sectional model to simulate the new particle formation events observed in Beijing, China. The simulation approximately captures how the events evolve. Further diagnosis shows that the oxygenated organic molecules may have been under-detected, and modulating their abundance leads to significantly improved simulation–observation agreement.
Joschka Pfeifer, Naser G. A. Mahfouz, Benjamin C. Schulze, Serge Mathot, Dominik Stolzenburg, Rima Baalbaki, Zoé Brasseur, Lucia Caudillo, Lubna Dada, Manuel Granzin, Xu-Cheng He, Houssni Lamkaddam, Brandon Lopez, Vladimir Makhmutov, Ruby Marten, Bernhard Mentler, Tatjana Müller, Antti Onnela, Maxim Philippov, Ana A. Piedehierro, Birte Rörup, Meredith Schervish, Ping Tian, Nsikanabasi S. Umo, Dongyu S. Wang, Mingyi Wang, Stefan K. Weber, André Welti, Yusheng Wu, Marcel Zauner-Wieczorek, Antonio Amorim, Imad El Haddad, Markku Kulmala, Katrianne Lehtipalo, Tuukka Petäjä, António Tomé, Sander Mirme, Hanna E. Manninen, Neil M. Donahue, Richard C. Flagan, Andreas Kürten, Joachim Curtius, and Jasper Kirkby
Atmos. Chem. Phys., 23, 6703–6718, https://doi.org/10.5194/acp-23-6703-2023, https://doi.org/10.5194/acp-23-6703-2023, 2023
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Attachment rate coefficients between ions and charged aerosol particles determine their lifetimes and may also influence cloud dynamics and aerosol processing. Here we present novel experiments that measure ion–aerosol attachment rate coefficients for multiply charged aerosol particles under atmospheric conditions in the CERN CLOUD chamber. Our results provide experimental discrimination between various theoretical models.
Yishuo Guo, Chenjuan Deng, Aino Ovaska, Feixue Zheng, Chenjie Hua, Junlei Zhan, Yiran Li, Jin Wu, Zongcheng Wang, Jiali Xie, Ying Zhang, Tingyu Liu, Yusheng Zhang, Boying Song, Wei Ma, Yongchun Liu, Chao Yan, Jingkun Jiang, Veli-Matti Kerminen, Men Xia, Tuomo Nieminen, Wei Du, Tom Kokkonen, and Markku Kulmala
Atmos. Chem. Phys., 23, 6663–6690, https://doi.org/10.5194/acp-23-6663-2023, https://doi.org/10.5194/acp-23-6663-2023, 2023
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Using the comprehensive datasets, we investigated the long-term variations of air pollutants during winter in Beijing from 2019 to 2022 and analyzed the characteristics of atmospheric pollution cocktail during different short-term special events (e.g., Beijing Winter Olympics, COVID lockdown and Chinese New Year) associated with substantial emission reductions. Our results are useful in planning more targeted and sustainable long-term pollution control plans.
Lucía Caudillo, Mihnea Surdu, Brandon Lopez, Mingyi Wang, Markus Thoma, Steffen Bräkling, Angela Buchholz, Mario Simon, Andrea C. Wagner, Tatjana Müller, Manuel Granzin, Martin Heinritzi, Antonio Amorim, David M. Bell, Zoé Brasseur, Lubna Dada, Jonathan Duplissy, Henning Finkenzeller, Xu-Cheng He, Houssni Lamkaddam, Naser G. A. Mahfouz, Vladimir Makhmutov, Hanna E. Manninen, Guillaume Marie, Ruby Marten, Roy L. Mauldin, Bernhard Mentler, Antti Onnela, Tuukka Petäjä, Joschka Pfeifer, Maxim Philippov, Ana A. Piedehierro, Birte Rörup, Wiebke Scholz, Jiali Shen, Dominik Stolzenburg, Christian Tauber, Ping Tian, António Tomé, Nsikanabasi Silas Umo, Dongyu S. Wang, Yonghong Wang, Stefan K. Weber, André Welti, Marcel Zauner-Wieczorek, Urs Baltensperger, Richard C. Flagan, Armin Hansel, Jasper Kirkby, Markku Kulmala, Katrianne Lehtipalo, Douglas R. Worsnop, Imad El Haddad, Neil M. Donahue, Alexander L. Vogel, Andreas Kürten, and Joachim Curtius
Atmos. Chem. Phys., 23, 6613–6631, https://doi.org/10.5194/acp-23-6613-2023, https://doi.org/10.5194/acp-23-6613-2023, 2023
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In this study, we present an intercomparison of four different techniques for measuring the chemical composition of nanoparticles. The intercomparison was performed based on the observed chemical composition, calculated volatility, and analysis of the thermograms. We found that the methods generally agree on the most important compounds that are found in the nanoparticles. However, they do see different parts of the organic spectrum. We suggest potential explanations for these differences.
Aliki Christodoulou, Iasonas Stavroulas, Mihalis Vrekoussis, Maximillien Desservettaz, Michael Pikridas, Elie Bimenyimana, Jonilda Kushta, Matic Ivančič, Martin Rigler, Philippe Goloub, Konstantina Oikonomou, Roland Sarda-Estève, Chrysanthos Savvides, Charbel Afif, Nikos Mihalopoulos, Stéphane Sauvage, and Jean Sciare
Atmos. Chem. Phys., 23, 6431–6456, https://doi.org/10.5194/acp-23-6431-2023, https://doi.org/10.5194/acp-23-6431-2023, 2023
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Our study presents, for the first time, a detailed source identification of aerosols at an urban background site in Cyprus (eastern Mediterranean), a region strongly impacted by climate change and air pollution. Here, we identify an unexpected high contribution of long-range transported pollution from fossil fuel sources in the Middle East, highlighting an urgent need to further characterize these fast-growing emissions and their impacts on regional atmospheric composition, climate, and health.
Christina N. Vasilakopoulou, Kalliopi Florou, Christos Kaltsonoudis, Iasonas Stavroulas, Nikolaos Mihalopoulos, and Spyros N. Pandis
Atmos. Meas. Tech., 16, 2837–2850, https://doi.org/10.5194/amt-16-2837-2023, https://doi.org/10.5194/amt-16-2837-2023, 2023
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The offline aerosol mass spectrometry technique is a useful tool for the source apportionment of organic aerosol in areas and periods during which an aerosol mass spectrometer is not available. In this work, an improved offline technique was developed and evaluated in an effort to capture most of the partially soluble and insoluble organic aerosol material, reducing the uncertainty of the corresponding source apportionment significantly.
Anton Rusanen, Kristo Hõrrak, Lauri R. Ahonen, Tuomo Nieminen, Pasi P. Aalto, Pasi Kolari, Markku Kulmala, Tuukka Petäjä, and Heikki Junninen
Atmos. Meas. Tech., 16, 2781–2793, https://doi.org/10.5194/amt-16-2781-2023, https://doi.org/10.5194/amt-16-2781-2023, 2023
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We present a framework for setting up SMEAR (Station for Measuring Ecosystem–Atmosphere Relations) type measurement station data flows. This framework, called SMEARcore, consists of modular open-source software components that can be chosen to suit various station configurations. The benefits of using this framework are automation of routine operations and real-time monitoring of measurement results.
Franz Martin Schnaiter, Claudia Linke, Eija Asmi, Henri Servomaa, Antti-Pekka Hyvärinen, Sho Ohata, Yutaka Kondo, and Emma Järvinen
Atmos. Meas. Tech., 16, 2753–2769, https://doi.org/10.5194/amt-16-2753-2023, https://doi.org/10.5194/amt-16-2753-2023, 2023
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Light-absorbing particles from combustion processes are important contributors to climate warming. Their highly variable spectral light absorption properties need to be monitored in the field. Commonly used methods show measurement artefacts that are difficult to correct. We introduce a new instrument that is based on the photoacoustic effect. Long-term operation in the Finnish Arctic demonstrates the applicability of the new instrument for unattended light absorption monitoring.
Eka Dian Pusfitasari, Jose Ruiz-Jimenez, Aleksi Tiusanen, Markus Suuronen, Jesse Haataja, Yusheng Wu, Juha Kangasluoma, Krista Luoma, Tuukka Petäjä, Matti Jussila, Kari Hartonen, and Marja-Liisa Riekkola
Atmos. Chem. Phys., 23, 5885–5904, https://doi.org/10.5194/acp-23-5885-2023, https://doi.org/10.5194/acp-23-5885-2023, 2023
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A miniaturized air-sampling drone system was successfully applied for the collection of volatile organic compounds (VOCs) and for the measurement of black carbon (BC) and total particle number concentrations in atmospheric air. Here we report, for the first time, the vertical profiles of BC and aerosol number concentrations above the boreal forest in Hyytiälä (Finland) at high altitudes close to the boundary layer in autumn 2021. VOC composition with its distribution was studied as well.
Dominik Stolzenburg, Tiia Laurila, Pasi Aalto, Joonas Vanhanen, Tuukka Petäjä, and Juha Kangasluoma
Atmos. Meas. Tech., 16, 2471–2483, https://doi.org/10.5194/amt-16-2471-2023, https://doi.org/10.5194/amt-16-2471-2023, 2023
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Size-distribution measurements of ultrafine particles are of special interest as they can be used to estimate the atmospheric significance of new particle formation, a process which is thought to influence the global climate. Here we show that improved counting statistics in size-distribution measurements through the usage of higher sampling flows can significantly reduce the uncertainties in such calculations.
Eleftherios Ioannidis, Kathy S. Law, Jean-Christophe Raut, Louis Marelle, Tatsuo Onishi, Rachel M. Kirpes, Lucia M. Upchurch, Thomas Tuch, Alfred Wiedensohler, Andreas Massling, Henrik Skov, Patricia K. Quinn, and Kerri A. Pratt
Atmos. Chem. Phys., 23, 5641–5678, https://doi.org/10.5194/acp-23-5641-2023, https://doi.org/10.5194/acp-23-5641-2023, 2023
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Remote and local anthropogenic emissions contribute to wintertime Arctic haze, with enhanced aerosol concentrations, but natural sources, which also contribute, are less well studied. Here, modelled wintertime sea-spray aerosols are improved in WRF-Chem over the wider Arctic by including updated wind speed and temperature-dependent treatments. As a result, anthropogenic nitrate aerosols are also improved. Open leads are confirmed to be the main source of sea-spray aerosols over northern Alaska.
Joanna E. Dyson, Lisa K. Whalley, Eloise J. Slater, Robert Woodward-Massey, Chunxiang Ye, James D. Lee, Freya Squires, James R. Hopkins, Rachel E. Dunmore, Marvin Shaw, Jacqueline F. Hamilton, Alastair C. Lewis, Stephen D. Worrall, Asan Bacak, Archit Mehra, Thomas J. Bannan, Hugh Coe, Carl J. Percival, Bin Ouyang, C. Nicholas Hewitt, Roderic L. Jones, Leigh R. Crilley, Louisa J. Kramer, W. Joe F. Acton, William J. Bloss, Supattarachai Saksakulkrai, Jingsha Xu, Zongbo Shi, Roy M. Harrison, Simone Kotthaus, Sue Grimmond, Yele Sun, Weiqi Xu, Siyao Yue, Lianfang Wei, Pingqing Fu, Xinming Wang, Stephen R. Arnold, and Dwayne E. Heard
Atmos. Chem. Phys., 23, 5679–5697, https://doi.org/10.5194/acp-23-5679-2023, https://doi.org/10.5194/acp-23-5679-2023, 2023
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The hydroxyl (OH) and closely coupled hydroperoxyl (HO2) radicals are vital for their role in the removal of atmospheric pollutants. In less polluted regions, atmospheric models over-predict HO2 concentrations. In this modelling study, the impact of heterogeneous uptake of HO2 onto aerosol surfaces on radical concentrations and the ozone production regime in Beijing in the summertime is investigated, and the implications for emissions policies across China are considered.
Rujing Yin, Xiaoxiao Li, Chao Yan, Runlong Cai, Ying Zhou, Juha Kangasluoma, Nina Sarnela, Janne Lampilahti, Tuukka Petäjä, Veli-Matti Kerminen, Federico Bianchi, Markku Kulmala, and Jingkun Jiang
Atmos. Chem. Phys., 23, 5279–5296, https://doi.org/10.5194/acp-23-5279-2023, https://doi.org/10.5194/acp-23-5279-2023, 2023
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Atmospheric cluster ions are important constituents in the atmosphere. However, the quantitative research on their compositions is still limited, especially in urban environments. Here we demonstrate the feasibility of an in situ quantification method of cluster ions measured by a high-resolution mass spectrometer and reveal their governing factors, sources, and sinks in urban Beijing through quantitative analysis of cluster ions, reagent ions, neutral molecules, and condensation sink.
Ting Lei, Hang Su, Nan Ma, Ulrich Pöschl, Alfred Wiedensohler, and Yafang Cheng
Atmos. Chem. Phys., 23, 4763–4774, https://doi.org/10.5194/acp-23-4763-2023, https://doi.org/10.5194/acp-23-4763-2023, 2023
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We investigate the hygroscopic behavior of levoglucosan and D-glucose nanoparticles using a nano-HTDMA. There is a weak size dependence of the hygroscopic growth factor of levoglucosan and D-glucose with diameters down to 20 nm, while a strong size dependence of the hygroscopic growth factor of D-glucose has been clearly observed in the size range 6 to 20 nm. The use of the DKA method leads to good agreement with the hygroscopic growth factor of glucose nanoparticles with diameters down to 6 nm.
Qiaozhi Zha, Wei Huang, Diego Aliaga, Otso Peräkylä, Liine Heikkinen, Alkuin Maximilian Koenig, Cheng Wu, Joonas Enroth, Yvette Gramlich, Jing Cai, Samara Carbone, Armin Hansel, Tuukka Petäjä, Markku Kulmala, Douglas Worsnop, Victoria Sinclair, Radovan Krejci, Marcos Andrade, Claudia Mohr, and Federico Bianchi
Atmos. Chem. Phys., 23, 4559–4576, https://doi.org/10.5194/acp-23-4559-2023, https://doi.org/10.5194/acp-23-4559-2023, 2023
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We investigate the chemical composition of atmospheric cluster ions from January to May 2018 at the high-altitude research station Chacaltaya (5240 m a.s.l.) in the Bolivian Andes. With state-of-the-art mass spectrometers and air mass history analysis, the measured cluster ions exhibited distinct diurnal and seasonal patterns, some of which contributed to new particle formation. Our study will improve the understanding of atmospheric ions and their role in high-altitude new particle formation.
Meri Räty, Larisa Sogacheva, Helmi-Marja Keskinen, Veli-Matti Kerminen, Tuomo Nieminen, Tuukka Petäjä, Ekaterina Ezhova, and Markku Kulmala
Atmos. Chem. Phys., 23, 3779–3798, https://doi.org/10.5194/acp-23-3779-2023, https://doi.org/10.5194/acp-23-3779-2023, 2023
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We utilised back trajectories to identify the source region of air masses arriving in Hyytiälä, Finland, and their travel time over forests. Combined with atmospheric observations, they revealed how air mass transport over the Fennoscandian boreal forest during the growing season produced an accumulation of cloud condensation nuclei and humidity, promoting cloudiness and precipitation. By 55 h of transport, air masses appeared to reach a balanced state with the forest environment.
Tuuli Miinalainen, Harri Kokkola, Antti Lipponen, Antti-Pekka Hyvärinen, Vijay Kumar Soni, Kari E. J. Lehtinen, and Thomas Kühn
Atmos. Chem. Phys., 23, 3471–3491, https://doi.org/10.5194/acp-23-3471-2023, https://doi.org/10.5194/acp-23-3471-2023, 2023
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We simulated the effects of aerosol emission mitigation on both global and regional radiative forcing and city-level air quality with a global-scale climate model. We used a machine learning downscaling approach to bias-correct the PM2.5 values obtained from the global model for the Indian megacity New Delhi. Our results indicate that aerosol mitigation could result in both improved air quality and less radiative heating for India.
Jing Cai, Kaspar R. Daellenbach, Cheng Wu, Yan Zheng, Feixue Zheng, Wei Du, Sophie L. Haslett, Qi Chen, Markku Kulmala, and Claudia Mohr
Atmos. Meas. Tech., 16, 1147–1165, https://doi.org/10.5194/amt-16-1147-2023, https://doi.org/10.5194/amt-16-1147-2023, 2023
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We introduce the offline application of FIGAERO-CIMS by analyzing Teflon and quartz filter samples that were collected at a typical urban site in Beijing with the deposition time varying from 30 min to 24 h. This method provides a feasible, simple, and quantitative way to investigate the molecular composition and volatility of OA compounds by using FIGAERO-CIMS to analyze offline samples.
Matti Kämäräinen, Juha-Pekka Tuovinen, Markku Kulmala, Ivan Mammarella, Juha Aalto, Henriikka Vekuri, Annalea Lohila, and Anna Lintunen
Biogeosciences, 20, 897–909, https://doi.org/10.5194/bg-20-897-2023, https://doi.org/10.5194/bg-20-897-2023, 2023
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In this study, we introduce a new method for modeling the exchange of carbon between the atmosphere and a study site located in a boreal forest in southern Finland. Our method yields more accurate results than previous approaches in this context. Accurately estimating carbon exchange is crucial for gaining a better understanding of the role of forests in regulating atmospheric carbon and addressing climate change.
Lejish Vettikkat, Pasi Miettinen, Angela Buchholz, Pekka Rantala, Hao Yu, Simon Schallhart, Tuukka Petäjä, Roger Seco, Elisa Männistö, Markku Kulmala, Eeva-Stiina Tuittila, Alex B. Guenther, and Siegfried Schobesberger
Atmos. Chem. Phys., 23, 2683–2698, https://doi.org/10.5194/acp-23-2683-2023, https://doi.org/10.5194/acp-23-2683-2023, 2023
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Wetlands cover a substantial fraction of the land mass in the northern latitudes, from northern Europe to Siberia and Canada. Yet, their isoprene and terpene emissions remain understudied. Here, we used a state-of-the-art measurement technique to quantify ecosystem-scale emissions from a boreal wetland during an unusually warm spring/summer. We found that the emissions from this wetland were (a) higher and (b) even more strongly dependent on temperature than commonly thought.
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, Klaus Pfeilsticker, Benjamin Weyland, Maria Dolores Andrés Hernández, and John P. Burrows
Atmos. Chem. Phys., 23, 2627–2647, https://doi.org/10.5194/acp-23-2627-2023, https://doi.org/10.5194/acp-23-2627-2023, 2023
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During the EMeRGe campaign in Asia, atmospheric pollutants were measured on board the HALO aircraft. The WRF-Chem model was employed to evaluate the biomass burning (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 in incoming shortwave radiation at the surface in southern China and the East China Sea, which potentially has significant regional climate implications.
Konstantinos Matthaios Doulgeris, Ville Vakkari, Ewan J. O'Connor, Veli-Matti Kerminen, Heikki Lihavainen, and David Brus
Atmos. Chem. Phys., 23, 2483–2498, https://doi.org/10.5194/acp-23-2483-2023, https://doi.org/10.5194/acp-23-2483-2023, 2023
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We investigated how different long-range-transported air masses can affect the microphysical properties of low-level clouds in a clean subarctic environment. A connection was revealed. Higher values of cloud droplet number concentrations were related to continental air masses, whereas the lowest values of number concentrations were related to marine air masses. These were characterized by larger cloud droplets. Clouds in all regions were sensitive to increases in cloud number concentration.
James Brean, David C. S. Beddows, Roy M. Harrison, Congbo Song, Peter Tunved, Johan Ström, Radovan Krejci, Eyal Freud, Andreas Massling, Henrik Skov, Eija Asmi, Angelo Lupi, and Manuel Dall'Osto
Atmos. Chem. Phys., 23, 2183–2198, https://doi.org/10.5194/acp-23-2183-2023, https://doi.org/10.5194/acp-23-2183-2023, 2023
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Our results emphasize how understanding the geographical variation in surface types across the Arctic is key to understanding secondary aerosol sources. We provide a harmonised analysis of new particle formation across the Arctic.
Adelaide Dinoi, Daniel Gulli, Kay Weinhold, Ivano Ammoscato, Claudia R. Calidonna, Alfred Wiedensohler, and Daniele Contini
Atmos. Chem. Phys., 23, 2167–2181, https://doi.org/10.5194/acp-23-2167-2023, https://doi.org/10.5194/acp-23-2167-2023, 2023
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In this study, particle number size distribution analysis was performed with the purpose of characterizing new particle formation (NPF) events occurring in two areas of southern Italy over 5 years of measurements. The identification of NPF events produced different results in terms of frequency and seasonality. Some of the main variables involved in the process, the local atmospheric conditions in which the events occurred, and the role of the air masses were discussed and compared.
Haley M. Royer, Mira L. Pöhlker, Ovid Krüger, Edmund Blades, Peter Sealy, Nurun Nahar Lata, Zezhen Cheng, Swarup China, Andrew P. Ault, Patricia K. Quinn, Paquita Zuidema, Christopher Pöhlker, Ulrich Pöschl, Meinrat Andreae, and Cassandra J. Gaston
Atmos. Chem. Phys., 23, 981–998, https://doi.org/10.5194/acp-23-981-2023, https://doi.org/10.5194/acp-23-981-2023, 2023
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This paper presents atmospheric particle chemical composition and measurements of aerosol water uptake properties collected at Ragged Point, Barbados, during the winter of 2020. The result of this study indicates the importance of small African smoke particles for cloud droplet formation in the tropical North Atlantic and highlights the large spatial and temporal pervasiveness of smoke over the Atlantic Ocean.
Wiebke Scholz, Jiali Shen, Diego Aliaga, Cheng Wu, Samara Carbone, Isabel Moreno, Qiaozhi Zha, Wei Huang, Liine Heikkinen, Jean Luc Jaffrezo, Gaelle Uzu, Eva Partoll, Markus Leiminger, Fernando Velarde, Paolo Laj, Patrick Ginot, Paolo Artaxo, Alfred Wiedensohler, Markku Kulmala, Claudia Mohr, Marcos Andrade, Victoria Sinclair, Federico Bianchi, and Armin Hansel
Atmos. Chem. Phys., 23, 895–920, https://doi.org/10.5194/acp-23-895-2023, https://doi.org/10.5194/acp-23-895-2023, 2023
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Dimethyl sulfide (DMS), emitted from the ocean, is the most abundant biogenic sulfur emission into the atmosphere. OH radicals, among others, can oxidize DMS to sulfuric and methanesulfonic acid, which are relevant for aerosol formation. We quantified DMS and nearly all DMS oxidation products with novel mass spectrometric instruments for gas and particle phase at the high mountain station Chacaltaya (5240 m a.s.l.) in the Bolivian Andes in free tropospheric air after long-range transport.
Johannes Mikkola, Victoria A. Sinclair, Marja Bister, and Federico Bianchi
Atmos. Chem. Phys., 23, 821–842, https://doi.org/10.5194/acp-23-821-2023, https://doi.org/10.5194/acp-23-821-2023, 2023
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Local winds in four valleys located in the Nepal Himalayas are studied by means of high-resolution meteorological modelling. Well-defined daytime up-valley winds are simulated in all of the valleys with some variation in the flow depth and strength among the valleys and their parts. Parts of the valleys with a steep valley floor inclination (2–5°) are associated with weaker and shallower daytime up-valley winds compared with the parts that have nearly flat valley floors (< 1°).
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., 23, 251–272, https://doi.org/10.5194/acp-23-251-2023, https://doi.org/10.5194/acp-23-251-2023, 2023
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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 strong aerosol nucleation and condensation in the UT is triggered by biogenic organics, 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.
Matthew Boyer, Diego Aliaga, Jakob Boyd Pernov, Hélène Angot, Lauriane L. J. Quéléver, Lubna Dada, Benjamin Heutte, Manuel Dall'Osto, David C. S. Beddows, Zoé Brasseur, Ivo Beck, Silvia Bucci, Marina Duetsch, Andreas Stohl, Tiia Laurila, Eija Asmi, Andreas Massling, Daniel Charles Thomas, Jakob Klenø Nøjgaard, Tak Chan, Sangeeta Sharma, Peter Tunved, Radovan Krejci, Hans Christen Hansson, Federico Bianchi, Katrianne Lehtipalo, Alfred Wiedensohler, Kay Weinhold, Markku Kulmala, Tuukka Petäjä, Mikko Sipilä, Julia Schmale, and Tuija Jokinen
Atmos. Chem. Phys., 23, 389–415, https://doi.org/10.5194/acp-23-389-2023, https://doi.org/10.5194/acp-23-389-2023, 2023
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The Arctic is a unique environment that is warming faster than other locations on Earth. We evaluate measurements of aerosol particles, which can influence climate, over the central Arctic Ocean for a full year and compare the data to land-based measurement stations across the Arctic. Our measurements show that the central Arctic has similarities to but also distinct differences from the stations further south. We note that this may change as the Arctic warms and sea ice continues to decline.
Yuan Wang, Silvia Henning, Laurent Poulain, Chunsong Lu, Frank Stratmann, Yuying Wang, Shengjie Niu, Mira L. Pöhlker, Hartmut Herrmann, and Alfred Wiedensohler
Atmos. Chem. Phys., 22, 15943–15962, https://doi.org/10.5194/acp-22-15943-2022, https://doi.org/10.5194/acp-22-15943-2022, 2022
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Aerosol particle activation affects cloud, precipitation, radiation, and thus the global climate. Its long-term measurements are important but still scarce. In this study, more than 4 years of measurements at a central European station were analyzed. The overall characteristics and seasonal changes of aerosol particle activation are summarized. The power-law fit between particle hygroscopicity factor and diameter was recommended for predicting cloud
condensation nuclei number concentration.
Mykhailo Savenets, Larysa Pysarenko, Svitlana Krakovska, Alexander Mahura, and Tuukka Petäjä
Atmos. Chem. Phys., 22, 15777–15791, https://doi.org/10.5194/acp-22-15777-2022, https://doi.org/10.5194/acp-22-15777-2022, 2022
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The paper explores the spatio-temporal variability of black carbon during a wildfire in August 2010, with a focus on Ukraine. As a research tool, the seamless Enviro-HIRLAM modelling system is used for investigating the atmospheric transport of aerosol particles emitted by wildfires from remote and local sources. The results of this study improve our understanding of the physical and chemical processes and the interactions of aerosols in the atmosphere.
Baseerat Romshoo, Mira Pöhlker, Alfred Wiedensohler, Sascha Pfeifer, Jorge Saturno, Andreas Nowak, Krzysztof Ciupek, Paul Quincey, Konstantina Vasilatou, Michaela N. Ess, Maria Gini, Konstantinos Eleftheriadis, Chris Robins, François Gaie-Levrel, and Thomas Müller
Atmos. Meas. Tech., 15, 6965–6989, https://doi.org/10.5194/amt-15-6965-2022, https://doi.org/10.5194/amt-15-6965-2022, 2022
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Black carbon (BC) is often assumed to be spherically shaped, causing uncertainties in its optical properties when modelled. This study investigates different modelling techniques for the optical properties of BC by comparing them to laboratory measurements. We provide experimental support for emphasizing the use of appropriate size representation (polydisperse size method) and morphological representation (aggregate morphology) for optical modelling and parameterization scheme development of BC.
Juha Sulo, Janne Lampilahti, Xuemeng Chen, Jenni Kontkanen, Tuomo Nieminen, Veli-Matti Kerminen, Tuukka Petäjä, Markku Kulmala, and Katrianne Lehtipalo
Atmos. Chem. Phys., 22, 15223–15242, https://doi.org/10.5194/acp-22-15223-2022, https://doi.org/10.5194/acp-22-15223-2022, 2022
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We measured atmospheric ion concentrations continuously in a boreal forest between 2005 and 2021 and observed an increasing interannual trend. The increase in cluster ion concentrations can be largely explained by an overall decreasing level of anthropogenic aerosols in the boreal forest. This suggests that the role of ions in atmospheric new particle formation may be more important in the future.
Santeri Tuovinen, Runlong Cai, Veli-Matti Kerminen, Jingkun Jiang, Chao Yan, Markku Kulmala, and Jenni Kontkanen
Atmos. Chem. Phys., 22, 15071–15091, https://doi.org/10.5194/acp-22-15071-2022, https://doi.org/10.5194/acp-22-15071-2022, 2022
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We compare observed survival probabilities of atmospheric particles from Beijing, China, with survival probabilities based on analytical formulae and model simulations. We find observed survival probabilities under polluted conditions at smaller sizes to be higher, while at larger sizes they are lower than or similar to theoretical survival probabilities. Uncertainties in condensation sink and growth rate are unlikely to explain higher-than-predicted survival probabilities at smaller sizes.
Matti Räsänen, Mika Aurela, Ville Vakkari, Johan P. Beukes, Juha-Pekka Tuovinen, Pieter G. Van Zyl, Miroslav Josipovic, Stefan J. Siebert, Tuomas Laurila, Markku Kulmala, Lauri Laakso, Janne Rinne, Ram Oren, and Gabriel Katul
Hydrol. Earth Syst. Sci., 26, 5773–5791, https://doi.org/10.5194/hess-26-5773-2022, https://doi.org/10.5194/hess-26-5773-2022, 2022
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The productivity of semiarid grazed grasslands is linked to the variation in rainfall and transpiration. By combining carbon dioxide and water flux measurements, we show that the annual transpiration is nearly constant during wet years while grasses react quickly to dry spells and drought, which reduce transpiration. The planning of annual grazing strategies could consider the early-season rainfall frequency that was linked to the portion of annual transpiration.
Runlong Cai, Chenjuan Deng, Dominik Stolzenburg, Chenxi Li, Junchen Guo, Veli-Matti Kerminen, Jingkun Jiang, Markku Kulmala, and Juha Kangasluoma
Atmos. Chem. Phys., 22, 14571–14587, https://doi.org/10.5194/acp-22-14571-2022, https://doi.org/10.5194/acp-22-14571-2022, 2022
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The survival probability of new particles is the key parameter governing their influences on the atmosphere and climate, yet the knowledge of particle survival in the atmosphere is rather limited. We propose methods to compute the size-resolved particle survival probability and validate them using simulations and measurements from diverse environments. Using these methods, we could explain particle survival from the cluster size to the cloud condensation nuclei size.
Mohamed Lamine Kassamba-Diaby, Corinne Galy-Lacaux, Veronique Yoboué, Jonathan E. Hickman, Kerneels Jaars, Sylvain Gnamien, Richmond Konan, Eric Gardrat, and Siele Silué
EGUsphere, https://doi.org/10.5194/egusphere-2022-994, https://doi.org/10.5194/egusphere-2022-994, 2022
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This work presents the chemical composition of precipitation from 2018 to 2020 at three sites representative of a south-north transect in Côte d'Ivoire. It includes two urban sites (Abidjan and Korhogo) and one rural site (Lamto). Measured rain chemical content and wet deposition fluxes highlights different dominant sources contributions i.e anthropogenic sources (traffic, construction, industry) at urban sites and biomass burning at the rural site.
Christina Vasilakopoulou, Iasonas Stavroulas, Nikolaos Mihalopoulos, and Spyros N. Pandis
Atmos. Meas. Tech., 15, 6419–6431, https://doi.org/10.5194/amt-15-6419-2022, https://doi.org/10.5194/amt-15-6419-2022, 2022
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Offline aerosol mass spectrometer (AMS) measurements can provide valuable information about ambient organic aerosols when online AMS measurements are not available. In this study, we examine whether and how the low time resolution (usually 24 h) of the offline technique affects source apportionment results. We concluded that use of the daily averages resulted in estimated average contributions that were within 8 % of the total OA compared with the high-resolution analysis.
Svetlana Sofieva, Eija Asmi, Nina S. Atanasova, Aino E. Heikkinen, Emeline Vidal, Jonathan Duplissy, Martin Romantschuk, Rostislav Kouznetsov, Jaakko Kukkonen, Dennis H. Bamford, Antti-Pekka Hyvärinen, and Mikhail Sofiev
Atmos. Meas. Tech., 15, 6201–6219, https://doi.org/10.5194/amt-15-6201-2022, https://doi.org/10.5194/amt-15-6201-2022, 2022
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A new bubble-generating glass chamber design with an extensive set of aerosol production experiments is presented to re-evaluate bubble-bursting-mediated aerosol production as a function of water parameters: bubbling air flow, water salinity, and temperature. Our main findings suggest modest dependence of aerosol production on the water salinity and a strong dependence on temperature below ~ 10 °C.
Chenjuan Deng, Yiran Li, Chao Yan, Jin Wu, Runlong Cai, Dongbin Wang, Yongchun Liu, Juha Kangasluoma, Veli-Matti Kerminen, Markku Kulmala, and Jingkun Jiang
Atmos. Chem. Phys., 22, 13569–13580, https://doi.org/10.5194/acp-22-13569-2022, https://doi.org/10.5194/acp-22-13569-2022, 2022
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The size distributions of urban atmospheric particles convey important information on their origins and impacts. This study investigates the characteristics of typical particle size distributions and key gaseous precursors in the long term in urban Beijing. A fitting function is proposed to represent and help interpret size distribution including particles and gaseous precursors. In addition to NPF (new particle formation) as the major source, vehicles can emit sub-3 nm particles as well
Loïc Gonzalez Carracedo, Katrianne Lehtipalo, Lauri R. Ahonen, Nina Sarnela, Sebastian Holm, Juha Kangasluoma, Markku Kulmala, Paul M. Winkler, and Dominik Stolzenburg
Atmos. Chem. Phys., 22, 13153–13166, https://doi.org/10.5194/acp-22-13153-2022, https://doi.org/10.5194/acp-22-13153-2022, 2022
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Fast nanoparticle growth is essential for the survival of new aerosol particles in the atmosphere and hence their contribution to the climate. We show that using naturally charged ions for growth calculations can cause a significant error. During the diurnal cycle, the importance of ion-induced and neutral nucleation varies, causing the ion population to have a slower measurable apparent growth. Results suggest that data from ion spectrometers need to be considered with great care below 3 nm.
Ville Leinonen, Harri Kokkola, Taina Yli-Juuti, Tero Mielonen, Thomas Kühn, Tuomo Nieminen, Simo Heikkinen, Tuuli Miinalainen, Tommi Bergman, Ken Carslaw, Stefano Decesari, Markus Fiebig, Tareq Hussein, Niku Kivekäs, Radovan Krejci, Markku Kulmala, Ari Leskinen, Andreas Massling, Nikos Mihalopoulos, Jane P. Mulcahy, Steffen M. Noe, Twan van Noije, Fiona M. O'Connor, Colin O'Dowd, Dirk Olivie, Jakob B. Pernov, Tuukka Petäjä, Øyvind Seland, Michael Schulz, Catherine E. Scott, Henrik Skov, Erik Swietlicki, Thomas Tuch, Alfred Wiedensohler, Annele Virtanen, and Santtu Mikkonen
Atmos. Chem. Phys., 22, 12873–12905, https://doi.org/10.5194/acp-22-12873-2022, https://doi.org/10.5194/acp-22-12873-2022, 2022
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We provide the first extensive comparison of detailed aerosol size distribution trends between in situ observations from Europe and five different earth system models. We investigated aerosol modes (nucleation, Aitken, and accumulation) separately and were able to show the differences between measured and modeled trends and especially their seasonal patterns. The differences in model results are likely due to complex effects of several processes instead of certain specific model features.
Marta Via, Gang Chen, Francesco Canonaco, Kaspar R. Daellenbach, Benjamin Chazeau, Hasna Chebaicheb, Jianhui Jiang, Hannes Keernik, Chunshui Lin, Nicolas Marchand, Cristina Marin, Colin O'Dowd, Jurgita Ovadnevaite, Jean-Eudes Petit, Michael Pikridas, Véronique Riffault, Jean Sciare, Jay G. Slowik, Leïla Simon, Jeni Vasilescu, Yunjiang Zhang, Olivier Favez, André S. H. Prévôt, Andrés Alastuey, and María Cruz Minguillón
Atmos. Meas. Tech., 15, 5479–5495, https://doi.org/10.5194/amt-15-5479-2022, https://doi.org/10.5194/amt-15-5479-2022, 2022
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This work presents the differences resulting from two techniques (rolling and seasonal) of the positive matrix factorisation model that can be run for organic aerosol source apportionment. The current state of the art suggests that the rolling technique is more accurate, but no proof of its effectiveness has been provided yet. This paper tackles this issue in the context of a synthetic dataset and a multi-site real-world comparison.
Ruiqi Man, Zhijun Wu, Taomou Zong, Aristeidis Voliotis, Yanting Qiu, Johannes Größ, Dominik van Pinxteren, Limin Zeng, Hartmut Herrmann, Alfred Wiedensohler, and Min Hu
Atmos. Chem. Phys., 22, 12387–12399, https://doi.org/10.5194/acp-22-12387-2022, https://doi.org/10.5194/acp-22-12387-2022, 2022
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Regional and total deposition doses for different age groups were quantified based on explicit hygroscopicity measurements. We found that particle hygroscopic growth led to a reduction (~24 %) in the total dose. The deposition rate of hygroscopic particles was higher in the daytime, while hydrophobic particles exhibited a higher rate at night and during rush hours. The results will deepen the understanding of the impact of hygroscopicity and the mixing state on deposition patterns in the lungs.
Chao Yan, Yicheng Shen, Dominik Stolzenburg, Lubna Dada, Ximeng Qi, Simo Hakala, Anu-Maija Sundström, Yishuo Guo, Antti Lipponen, Tom V. Kokkonen, Jenni Kontkanen, Runlong Cai, Jing Cai, Tommy Chan, Liangduo Chen, Biwu Chu, Chenjuan Deng, Wei Du, Xiaolong Fan, Xu-Cheng He, Juha Kangasluoma, Joni Kujansuu, Mona Kurppa, Chang Li, Yiran Li, Zhuohui Lin, Yiliang Liu, Yuliang Liu, Yiqun Lu, Wei Nie, Jouni Pulliainen, Xiaohui Qiao, Yonghong Wang, Yifan Wen, Ye Wu, Gan Yang, Lei Yao, Rujing Yin, Gen Zhang, Shaojun Zhang, Feixue Zheng, Ying Zhou, Antti Arola, Johanna Tamminen, Pauli Paasonen, Yele Sun, Lin Wang, Neil M. Donahue, Yongchun Liu, Federico Bianchi, Kaspar R. Daellenbach, Douglas R. Worsnop, Veli-Matti Kerminen, Tuukka Petäjä, Aijun Ding, Jingkun Jiang, and Markku Kulmala
Atmos. Chem. Phys., 22, 12207–12220, https://doi.org/10.5194/acp-22-12207-2022, https://doi.org/10.5194/acp-22-12207-2022, 2022
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Atmospheric new particle formation (NPF) is a dominant source of atmospheric ultrafine particles. In urban environments, traffic emissions are a major source of primary pollutants, but their contribution to NPF remains under debate. During the COVID-19 lockdown, traffic emissions were significantly reduced, providing a unique chance to examine their relevance to NPF. Based on our comprehensive measurements, we demonstrate that traffic emissions alone are not able to explain the NPF in Beijing.
Outi Meinander, Pavla Dagsson-Waldhauserova, Pavel Amosov, Elena Aseyeva, Cliff Atkins, Alexander Baklanov, Clarissa Baldo, Sarah L. Barr, Barbara Barzycka, Liane G. Benning, Bojan Cvetkovic, Polina Enchilik, Denis Frolov, Santiago Gassó, Konrad Kandler, Nikolay Kasimov, Jan Kavan, James King, Tatyana Koroleva, Viktoria Krupskaya, Markku Kulmala, Monika Kusiak, Hanna K. Lappalainen, Michał Laska, Jerome Lasne, Marek Lewandowski, Bartłomiej Luks, James B. McQuaid, Beatrice Moroni, Benjamin Murray, Ottmar Möhler, Adam Nawrot, Slobodan Nickovic, Norman T. O’Neill, Goran Pejanovic, Olga Popovicheva, Keyvan Ranjbar, Manolis Romanias, Olga Samonova, Alberto Sanchez-Marroquin, Kerstin Schepanski, Ivan Semenkov, Anna Sharapova, Elena Shevnina, Zongbo Shi, Mikhail Sofiev, Frédéric Thevenet, Throstur Thorsteinsson, Mikhail Timofeev, Nsikanabasi Silas Umo, Andreas Uppstu, Darya Urupina, György Varga, Tomasz Werner, Olafur Arnalds, and Ana Vukovic Vimic
Atmos. Chem. Phys., 22, 11889–11930, https://doi.org/10.5194/acp-22-11889-2022, https://doi.org/10.5194/acp-22-11889-2022, 2022
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High-latitude dust (HLD) is a short-lived climate forcer, air pollutant, and nutrient source. Our results suggest a northern HLD belt at 50–58° N in Eurasia and 50–55° N in Canada and at >60° N in Eurasia and >58° N in Canada. Our addition to the previously identified global dust belt (GDB) provides crucially needed information on the extent of active HLD sources with both direct and indirect impacts on climate and environment in remote regions, which are often poorly understood and predicted.
Micael Amore Cecchini, Marco de Bruine, Jordi Vilà-Guerau de Arellano, and Paulo Artaxo
Atmos. Chem. Phys., 22, 11867–11888, https://doi.org/10.5194/acp-22-11867-2022, https://doi.org/10.5194/acp-22-11867-2022, 2022
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Shallow clouds (vertical extent up to 3 km height) are ubiquitous throughout the Amazon and are responsible for redistributing the solar heat and moisture vertically and horizontally. They are a key component of the water cycle because they can grow past the shallow phase to contribute significantly to the precipitation formation. However, they need favourable environmental conditions to grow. In this study, we analyse how changing wind patterns affect the development of such shallow clouds.
Sini Isokääntä, Paul Kim, Santtu Mikkonen, Thomas Kühn, Harri Kokkola, Taina Yli-Juuti, Liine Heikkinen, Krista Luoma, Tuukka Petäjä, Zak Kipling, Daniel Partridge, and Annele Virtanen
Atmos. Chem. Phys., 22, 11823–11843, https://doi.org/10.5194/acp-22-11823-2022, https://doi.org/10.5194/acp-22-11823-2022, 2022
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This research employs air mass history analysis and observations to study how clouds and precipitation affect atmospheric aerosols during transport to a boreal forest site. The mass concentrations of studied chemical species showed exponential decrease as a function of accumulated rain along the air mass route. Our analysis revealed in-cloud sulfate formation, while no major changes in organic mass were seen. Most of the in-cloud-formed sulfate could be assigned to particle sizes above 200 nm.
Runlong Cai, Ella Häkkinen, Chao Yan, Jingkun Jiang, Markku Kulmala, and Juha Kangasluoma
Atmos. Chem. Phys., 22, 11529–11541, https://doi.org/10.5194/acp-22-11529-2022, https://doi.org/10.5194/acp-22-11529-2022, 2022
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The influences of new particle formation on the climate and air quality are governed by particle survival, which has been under debate due to uncertainties in the coagulation sink. Here we measure the coagulation coefficient of sub-10 nm particles and demonstrate that collisions between the freshly nucleated and background particles can effectively lead to coagulation. We further show that the effective coagulation sink is consistent with the new particle formation measured in urban Beijing.
Benjamin Foreback, Lubna Dada, Kaspar R. Daellenbach, Chao Yan, Lili Wang, Biwu Chu, Ying Zhou, Tom V. Kokkonen, Mona Kurppa, Rosaria E. Pileci, Yonghong Wang, Tommy Chan, Juha Kangasluoma, Lin Zhuohui, Yishou Guo, Chang Li, Rima Baalbaki, Joni Kujansuu, Xiaolong Fan, Zemin Feng, Pekka Rantala, Shahzad Gani, Federico Bianchi, Veli-Matti Kerminen, Tuukka Petäjä, Markku Kulmala, Yongchun Liu, and Pauli Paasonen
Atmos. Chem. Phys., 22, 11089–11104, https://doi.org/10.5194/acp-22-11089-2022, https://doi.org/10.5194/acp-22-11089-2022, 2022
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This study analyzed air quality in Beijing during the Chinese New Year over 7 years, including data from a new in-depth measurement station. This is one of few studies to look at long-term impacts, including the outcome of firework restrictions starting in 2018. Results show that firework pollution has gone down since 2016, indicating a positive result from the restrictions. Results of this study may be useful in making future decisions about the use of fireworks to improve air quality.
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, https://doi.org/10.5194/acp-22-10901-2022, https://doi.org/10.5194/acp-22-10901-2022, 2022
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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.
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, https://doi.org/10.5194/acp-22-10139-2022, https://doi.org/10.5194/acp-22-10139-2022, 2022
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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
Yishuo Guo, Chao Yan, Yuliang Liu, Xiaohui Qiao, Feixue Zheng, Ying Zhang, Ying Zhou, Chang Li, Xiaolong Fan, Zhuohui Lin, Zemin Feng, Yusheng Zhang, Penggang Zheng, Linhui Tian, Wei Nie, Zhe Wang, Dandan Huang, Kaspar R. Daellenbach, Lei Yao, Lubna Dada, Federico Bianchi, Jingkun Jiang, Yongchun Liu, Veli-Matti Kerminen, and Markku Kulmala
Atmos. Chem. Phys., 22, 10077–10097, https://doi.org/10.5194/acp-22-10077-2022, https://doi.org/10.5194/acp-22-10077-2022, 2022
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Gaseous oxygenated organic molecules (OOMs) are able to form atmospheric aerosols, which will impact on human health and climate change. Here, we find that OOMs in urban Beijing are dominated by anthropogenic sources, i.e. aromatic (29 %–41 %) and aliphatic (26 %–41 %) OOMs. They are also the main contributors to the condensational growth of secondary organic aerosols (SOAs). Therefore, the restriction on anthropogenic VOCs is crucial for the reduction of SOAs and haze formation.
Carlton Xavier, Metin Baykara, Robin Wollesen de Jonge, Barbara Altstädter, Petri Clusius, Ville Vakkari, Roseline Thakur, Lisa Beck, Silvia Becagli, Mirko Severi, Rita Traversi, Radovan Krejci, Peter Tunved, Mauro Mazzola, Birgit Wehner, Mikko Sipilä, Markku Kulmala, Michael Boy, and Pontus Roldin
Atmos. Chem. Phys., 22, 10023–10043, https://doi.org/10.5194/acp-22-10023-2022, https://doi.org/10.5194/acp-22-10023-2022, 2022
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The focus of this work is to study and improve our understanding of processes involved in the formation and growth of new particles in a remote Arctic marine environment. We run the 1D model ADCHEM along air mass trajectories arriving at Ny-Ålesund in May 2018. The model finds that ion-mediated H2SO4–NH3 nucleation can explain the observed new particle formation at Ny-Ålesund. The growth of particles is driven via H2SO4 condensation and formation of methane sulfonic acid in the aqueous phase.
Alexander D. Harrison, Daniel O'Sullivan, Michael P. Adams, Grace C. E. Porter, Edmund Blades, Cherise Brathwaite, Rebecca Chewitt-Lucas, Cassandra Gaston, Rachel Hawker, Ovid O. Krüger, Leslie Neve, Mira L. Pöhlker, Christopher Pöhlker, Ulrich Pöschl, Alberto Sanchez-Marroquin, Andrea Sealy, Peter Sealy, Mark D. Tarn, Shanice Whitehall, James B. McQuaid, Kenneth S. Carslaw, Joseph M. Prospero, and Benjamin J. Murray
Atmos. Chem. Phys., 22, 9663–9680, https://doi.org/10.5194/acp-22-9663-2022, https://doi.org/10.5194/acp-22-9663-2022, 2022
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The formation of ice in clouds fundamentally alters cloud properties; hence it is important we understand the special aerosol particles that can nucleate ice when immersed in supercooled cloud droplets. In this paper we show that African desert dust that has travelled across the Atlantic to the Caribbean nucleates ice much less well than we might have expected.
Haobin Zhong, Ru-Jin Huang, Chunshui Lin, Wei Xu, Jing Duan, Yifang Gu, Wei Huang, Haiyan Ni, Chongshu Zhu, Yan You, Yunfei Wu, Renjian Zhang, Jurgita Ovadnevaite, Darius Ceburnis, and Colin D. O'Dowd
Atmos. Chem. Phys., 22, 9513–9524, https://doi.org/10.5194/acp-22-9513-2022, https://doi.org/10.5194/acp-22-9513-2022, 2022
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To investigate the physico-chemical properties of aerosol transported from major pollution regions in China, observations were conducted ~200 m above the ground at the junction location of the two key pollution areas. We found that the formation efficiency, oxidation state and production rate of secondary aerosol were different in the transport sectors from different pollution regions, and they were largely enhanced by the regional long-distance transport.
Ivo Beck, Hélène Angot, Andrea Baccarini, Lubna Dada, Lauriane Quéléver, Tuija Jokinen, Tiia Laurila, Markus Lampimäki, Nicolas Bukowiecki, Matthew Boyer, Xianda Gong, Martin Gysel-Beer, Tuukka Petäjä, Jian Wang, and Julia Schmale
Atmos. Meas. Tech., 15, 4195–4224, https://doi.org/10.5194/amt-15-4195-2022, https://doi.org/10.5194/amt-15-4195-2022, 2022
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We present the pollution detection algorithm (PDA), a new method to identify local primary pollution in remote atmospheric aerosol and trace gas time series. The PDA identifies periods of contaminated data and relies only on the target dataset itself; i.e., it is independent of ancillary data such as meteorological variables. The parameters of all pollution identification steps are adjustable so that the PDA can be tuned to different locations and situations. It is available as open-access code.
Dimitrios Bousiotis, David C. S. Beddows, Ajit Singh, Molly Haugen, Sebastián Diez, Pete M. Edwards, Adam Boies, Roy M. Harrison, and Francis D. Pope
Atmos. Meas. Tech., 15, 4047–4061, https://doi.org/10.5194/amt-15-4047-2022, https://doi.org/10.5194/amt-15-4047-2022, 2022
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In the last decade, low-cost sensors have revolutionised the field of air quality monitoring. This paper extends the ability of low-cost sensors to not only measure air pollution, but also to understand where the pollution comes from. This "source apportionment" is a critical step in air quality management to allow for the mitigation of air pollution. The techniques developed in this paper have the potential for great impact in both research and industrial applications.
Ovid O. Krüger, Bruna A. Holanda, Sourangsu Chowdhury, Andrea Pozzer, David Walter, Christopher Pöhlker, Maria Dolores Andrés Hernández, John P. Burrows, Christiane Voigt, Jos Lelieveld, Johannes Quaas, Ulrich Pöschl, and Mira L. Pöhlker
Atmos. Chem. Phys., 22, 8683–8699, https://doi.org/10.5194/acp-22-8683-2022, https://doi.org/10.5194/acp-22-8683-2022, 2022
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The abrupt reduction in human activities during the first COVID-19 lockdown created unprecedented atmospheric conditions. We took the opportunity to quantify changes in black carbon (BC) as a major anthropogenic air pollutant. Therefore, we measured BC on board a research aircraft over Europe during the lockdown and compared the results to measurements from 2017. With model simulations we account for different weather conditions and find a lockdown-related decrease in BC of 41 %.
Lisa J. Beck, Siegfried Schobesberger, Heikki Junninen, Janne Lampilahti, Antti Manninen, Lubna Dada, Katri Leino, Xu-Cheng He, Iida Pullinen, Lauriane L. J. Quéléver, Anna Franck, Pyry Poutanen, Daniela Wimmer, Frans Korhonen, Mikko Sipilä, Mikael Ehn, Douglas R. Worsnop, Veli-Matti Kerminen, Tuukka Petäjä, Markku Kulmala, and Jonathan Duplissy
Atmos. Chem. Phys., 22, 8547–8577, https://doi.org/10.5194/acp-22-8547-2022, https://doi.org/10.5194/acp-22-8547-2022, 2022
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The presented article introduces an overview of atmospheric ions and their composition above the boreal forest. We provide the results of an extensive airborne measurement campaign with an air ion mass spectrometer and particle measurements, showing their diurnal evolution within the boundary layer and free troposphere. In addition, we compare the airborne dataset with the co-located data from the ground at SMEAR II station, Finland.
Karine Sartelet, Youngseob Kim, Florian Couvidat, Maik Merkel, Tuukka Petäjä, Jean Sciare, and Alfred Wiedensohler
Atmos. Chem. Phys., 22, 8579–8596, https://doi.org/10.5194/acp-22-8579-2022, https://doi.org/10.5194/acp-22-8579-2022, 2022
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A methodology is defined to estimate number emissions from an inventory providing mass emissions. Number concentrations are simulated over Greater Paris using different nucleation parameterisations (binary, ternary involving sulfuric acid and ammonia, and heteromolecular involving sulfuric acid and extremely low-volatility organics, ELVOCs). The comparisons show that ternary nucleation may not be a dominant process for new particle formation in cities, but they stress the role of ELVOCs.
Simon Kirschler, Christiane Voigt, Bruce Anderson, Ramon Campos Braga, Gao Chen, Andrea F. Corral, Ewan Crosbie, Hossein Dadashazar, Richard A. Ferrare, Valerian Hahn, Johannes Hendricks, Stefan Kaufmann, Richard Moore, Mira L. Pöhlker, Claire Robinson, Amy J. Scarino, Dominik Schollmayer, Michael A. Shook, K. Lee Thornhill, Edward Winstead, Luke D. Ziemba, and Armin Sorooshian
Atmos. Chem. Phys., 22, 8299–8319, https://doi.org/10.5194/acp-22-8299-2022, https://doi.org/10.5194/acp-22-8299-2022, 2022
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In this study we show that the vertical velocity dominantly impacts the cloud droplet number concentration (NC) of low-level clouds over the western North Atlantic in the winter and summer season, while the cloud condensation nuclei concentration, aerosol size distribution and chemical composition impact NC within a season. The observational data presented in this study can evaluate and improve the representation of aerosol–cloud interactions for a wide range of conditions.
Luka Drinovec, Uroš Jagodič, Luka Pirker, Miha Škarabot, Mario Kurtjak, Kristijan Vidović, Luca Ferrero, Bradley Visser, Jannis Röhrbein, Ernest Weingartner, Daniel M. Kalbermatter, Konstantina Vasilatou, Tobias Bühlmann, Celine Pascale, Thomas Müller, Alfred Wiedensohler, and Griša Močnik
Atmos. Meas. Tech., 15, 3805–3825, https://doi.org/10.5194/amt-15-3805-2022, https://doi.org/10.5194/amt-15-3805-2022, 2022
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A new photothermal interferometer (PTAAM-2λ) for artefact-free determination of the aerosol absorption coefficient at two wavelengths is presented. The instrument is calibrated with NO2 and polydisperse nigrosin, resulting in very low uncertainties of the absorption coefficients: 4 % at 532 nm and 6 % at 1064 nm. The instrument’s performance makes the PTAAM-2λ a strong candidate for reference measurements of the aerosol absorption coefficient.
Miska Olin, Magdalena Okuljar, Matti P. Rissanen, Joni Kalliokoski, Jiali Shen, Lubna Dada, Markus Lampimäki, Yusheng Wu, Annalea Lohila, Jonathan Duplissy, Mikko Sipilä, Tuukka Petäjä, Markku Kulmala, and Miikka Dal Maso
Atmos. Chem. Phys., 22, 8097–8115, https://doi.org/10.5194/acp-22-8097-2022, https://doi.org/10.5194/acp-22-8097-2022, 2022
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Atmospheric new particle formation is an important source of the total particle number concentration in the atmosphere. Several parameters for predicting new particle formation events have been suggested before, but the results have been inconclusive. This study proposes an another predicting parameter, related to a specific type of highly oxidized organic molecules, especially for similar locations to the measurement site in this study, which was a coastal agricultural site in Finland.
Victoria Anne Sinclair, Jenna Ritvanen, Gabin Urbancic, Irene Erner, Yurii Batrak, Dmitri Moisseev, and Mona Kurppa
Atmos. Meas. Tech., 15, 3075–3103, https://doi.org/10.5194/amt-15-3075-2022, https://doi.org/10.5194/amt-15-3075-2022, 2022
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We investigate the boundary-layer (BL) height and surface stability in southern Finland using radiosondes, a microwave radiometer and ERA5 reanalysis. Accurately quantifying the BL height is challenging, and the diagnosed BL height can depend strongly on the method used. Microwave radiometers provide reliable estimates of the BL height but only in unstable conditions. ERA5 captures the BL height well except under very stable conditions, which occur most commonly at night during the warm season.
Roseline C. Thakur, Lubna Dada, Lisa J. Beck, Lauriane L. J. Quéléver, Tommy Chan, Marjan Marbouti, Xu-Cheng He, Carlton Xavier, Juha Sulo, Janne Lampilahti, Markus Lampimäki, Yee Jun Tham, Nina Sarnela, Katrianne Lehtipalo, Alf Norkko, Markku Kulmala, Mikko Sipilä, and Tuija Jokinen
Atmos. Chem. Phys., 22, 6365–6391, https://doi.org/10.5194/acp-22-6365-2022, https://doi.org/10.5194/acp-22-6365-2022, 2022
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Every year intense cyanobacterial and macroalgal blooms occur in the Baltic Sea and in the coastal areas surrounding Helsinki, yet no studies have addressed the impact of biogenic emissions from these blooms on gas vapor concentrations, which in turn could influence new particle formation. This is the first study of its kind to address the chemistry driving new particle formation (NPF) during a bloom period in this region, highlighting the role of biogenic sulfuric acid and iodic acid.
Ajit Ahlawat, Kay Weinhold, Jesus Marval, Paolo Tronville, Ari Leskinen, Mika Komppula, Holger Gerwig, Lars Gerling, Stephan Weber, Rikke Bramming Jørgensen, Thomas Nørregaard Jensen, Marouane Merizak, Ulrich Vogt, Carla Ribalta, Mar Viana, Andre Schmitz, Maria Chiesa, Giacomo Gerosa, Lothar Keck, Markus Pesch, Gerhard Steiner, Thomas Krinke, Torsten Tritscher, Wolfram Birmili, and Alfred Wiedensohler
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2022-155, https://doi.org/10.5194/amt-2022-155, 2022
Revised manuscript not accepted
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Measurements of ultrafine particles must be done with quality-assured instruments. The performance of portable instruments such as NanoScan SMPS, and GRIMM Mini WRAS spectrometer measuring the particle number size distribution in the range from 10 to 200 nm were investigated. The influence of different aerosol types and maintenance activities on these instruments were explored. The results show that these portable instruments are suitable for mobile UFP measurements for source identification.
Russell J. Perkins, Peter J. Marinescu, Ezra J. T. Levin, Don R. Collins, and Sonia M. Kreidenweis
Atmos. Chem. Phys., 22, 6197–6215, https://doi.org/10.5194/acp-22-6197-2022, https://doi.org/10.5194/acp-22-6197-2022, 2022
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We used 5 years (2009–2013) of aerosol and cloud condensation nuclei (CCN) data from a total of seven instruments housed at the Southern Great Plains site, which were merged into a quality-controlled, continuous dataset of CCN spectra at ~45 min resolution. The data cover all seasons, are representative of a rural, agricultural mid-continental site, and are useful for model initialization and validation. Our analysis of this dataset focuses on seasonal and hourly variability.
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, https://doi.org/10.5194/acp-22-5877-2022, https://doi.org/10.5194/acp-22-5877-2022, 2022
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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.
Petra Pokorná, Naděžda Zíková, Petr Vodička, Radek Lhotka, Saliou Mbengue, Adéla Holubová Šmejkalová, Véronique Riffault, Jakub Ondráček, Jaroslav Schwarz, and Vladimír Ždímal
Atmos. Chem. Phys., 22, 5829–5858, https://doi.org/10.5194/acp-22-5829-2022, https://doi.org/10.5194/acp-22-5829-2022, 2022
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By examining individual episodes of high mass and number concentrations, we show that the seasonality in the physicochemical properties of aerosol particles was caused by the sources' diversity and was related to the different air masses and meteorology. We also confirmed the relation between particle size and age that is reflected in oxidation state and shape (difference in densities; effective vs. material). The results have general validity and thus transcend the study regional character.
Kristina Glojek, Griša Močnik, Honey Dawn C. Alas, Andrea Cuesta-Mosquera, Luka Drinovec, Asta Gregorič, Matej Ogrin, Kay Weinhold, Irena Ježek, Thomas Müller, Martin Rigler, Maja Remškar, Dominik van Pinxteren, Hartmut Herrmann, Martina Ristorini, Maik Merkel, Miha Markelj, and Alfred Wiedensohler
Atmos. Chem. Phys., 22, 5577–5601, https://doi.org/10.5194/acp-22-5577-2022, https://doi.org/10.5194/acp-22-5577-2022, 2022
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A pilot study to determine the emissions of wood burning under
real-world laboratoryconditions was conducted. We found that measured black carbon (eBC) and particulate matter (PM) in rural shallow terrain depressions with residential wood burning could be much greater than predicted by models. The exceeding levels are a cause for concern since similar conditions can be expected in numerous hilly and mountainous regions across Europe, where approximately 20 % of the total population lives.
Ruochong Xu, Joel A. Thornton, Ben H. Lee, Yanxu Zhang, Lyatt Jaeglé, Felipe D. Lopez-Hilfiker, Pekka Rantala, and Tuukka Petäjä
Atmos. Chem. Phys., 22, 5477–5494, https://doi.org/10.5194/acp-22-5477-2022, https://doi.org/10.5194/acp-22-5477-2022, 2022
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Monoterpenes are emitted into the atmosphere by vegetation and by the use of certain consumer products. Reactions of monoterpenes in the atmosphere lead to low-volatility products that condense to grow particulate matter or participate in new particle formation and, thus, affect air quality and climate. We use a model of atmospheric chemistry and transport to evaluate the global-scale importance of recent updates to our understanding of monoterpene chemistry in particle formation and growth.
Ülkü Alver Şahin, Roy M. Harrison, Mohammed S. Alam, David C. S. Beddows, Dimitrios Bousiotis, Zongbo Shi, Leigh R. Crilley, William Bloss, James Brean, Isha Khanna, and Rulan Verma
Atmos. Chem. Phys., 22, 5415–5433, https://doi.org/10.5194/acp-22-5415-2022, https://doi.org/10.5194/acp-22-5415-2022, 2022
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Wide-range particle size spectra have been measured in three seasons in Delhi and are interpreted in terms of sources and processes. Condensational growth is a major feature of the fine fraction, and a coarse fraction contributes substantially – but only in summer.
Michael Weger, Holger Baars, Henriette Gebauer, Maik Merkel, Alfred Wiedensohler, and Bernd Heinold
Geosci. Model Dev., 15, 3315–3345, https://doi.org/10.5194/gmd-15-3315-2022, https://doi.org/10.5194/gmd-15-3315-2022, 2022
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Numerical models are an important tool to assess the air quality in cities,
as they can provide near-continouos data in time and space. In this paper,
air pollution for an entire city is simulated at a high spatial resolution of 40 m.
At this spatial scale, the effects of buildings on the atmosphere,
like channeling or blocking of the air flow, are directly represented by diffuse obstacles in the used model CAIRDIO. For model validation, measurements from air-monitoring sites are used.
Xianda Gong, Heike Wex, Thomas Müller, Silvia Henning, Jens Voigtländer, Alfred Wiedensohler, and Frank Stratmann
Atmos. Chem. Phys., 22, 5175–5194, https://doi.org/10.5194/acp-22-5175-2022, https://doi.org/10.5194/acp-22-5175-2022, 2022
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We conducted 10 yr measurements to characterize the atmospheric aerosol at Cabo Verde. An unsupervised machine learning algorithm, K-means, was implemented to study the aerosol types. Cloud condensation nuclei number concentrations during dust periods were 2.5 times higher than marine periods. The long-term data sets, together with the aerosol classification, can be used as a basis to improve understanding of annual cycles of aerosol, and aerosol-cloud interactions in the North Atlantic.
Jarmo Mäkelä, Laila Melkas, Ivan Mammarella, Tuomo Nieminen, Suyog Chandramouli, Rafael Savvides, and Kai Puolamäki
Biogeosciences, 19, 2095–2099, https://doi.org/10.5194/bg-19-2095-2022, https://doi.org/10.5194/bg-19-2095-2022, 2022
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Causal structure discovery algorithms have been making headway into Earth system sciences, and they can be used to increase our understanding on biosphere–atmosphere interactions. In this paper we present a procedure on how to utilize prior knowledge of the domain experts together with these algorithms in order to find more robust causal structure models. We also demonstrate how to avoid pitfalls such as over-fitting and concept drift during this process.
Zoé Brasseur, Dimitri Castarède, Erik S. Thomson, Michael P. Adams, Saskia Drossaart van Dusseldorp, Paavo Heikkilä, Kimmo Korhonen, Janne Lampilahti, Mikhail Paramonov, Julia Schneider, Franziska Vogel, Yusheng Wu, Jonathan P. D. Abbatt, Nina S. Atanasova, Dennis H. Bamford, Barbara Bertozzi, Matthew Boyer, David Brus, Martin I. Daily, Romy Fösig, Ellen Gute, Alexander D. Harrison, Paula Hietala, Kristina Höhler, Zamin A. Kanji, Jorma Keskinen, Larissa Lacher, Markus Lampimäki, Janne Levula, Antti Manninen, Jens Nadolny, Maija Peltola, Grace C. E. Porter, Pyry Poutanen, Ulrike Proske, Tobias Schorr, Nsikanabasi Silas Umo, János Stenszky, Annele Virtanen, Dmitri Moisseev, Markku Kulmala, Benjamin J. Murray, Tuukka Petäjä, Ottmar Möhler, and Jonathan Duplissy
Atmos. Chem. Phys., 22, 5117–5145, https://doi.org/10.5194/acp-22-5117-2022, https://doi.org/10.5194/acp-22-5117-2022, 2022
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The present measurement report introduces the ice nucleation campaign organized in Hyytiälä, Finland, in 2018 (HyICE-2018). We provide an overview of the campaign settings, and we describe the measurement infrastructure and operating procedures used. In addition, we use results from ice nucleation instrument inter-comparison to show that the suite of these instruments deployed during the campaign reports consistent results.
Aki Virkkula, Henrik Grythe, John Backman, Tuukka Petäjä, Maurizio Busetto, Christian Lanconelli, Angelo Lupi, Silvia Becagli, Rita Traversi, Mirko Severi, Vito Vitale, Patrick Sheridan, and Elisabeth Andrews
Atmos. Chem. Phys., 22, 5033–5069, https://doi.org/10.5194/acp-22-5033-2022, https://doi.org/10.5194/acp-22-5033-2022, 2022
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Optical properties of surface aerosols at Dome C, Antarctica, in 2007–2013 and their potential source areas are presented. The equivalent black carbon (eBC) mass concentrations were compared with eBC measured at three other Antarctic sites: the South Pole (SPO) and two coastal sites, Neumayer and Syowa. Transport analysis suggests that South American BC emissions are the largest contributor to eBC at Dome C.
Wei Ma, Zemin Feng, Junlei Zhan, Yongchun Liu, Pengfei Liu, Chengtang Liu, Qingxin Ma, Kang Yang, Yafei Wang, Hong He, Markku Kulmala, Yujing Mu, and Junfeng Liu
Atmos. Chem. Phys., 22, 4841–4851, https://doi.org/10.5194/acp-22-4841-2022, https://doi.org/10.5194/acp-22-4841-2022, 2022
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The influence of photochemical loss of volatile organic compounds (VOCS) on O3 formation is investigated using an observation-based model. The sensitivity regime of ozone formation might be misdiagnosed due to the photochemical loss of VOCs in the atmosphere. The contribution of local photochemistry is underestimated regarding O3 pollution when one does not consider the photochemical loss of VOCs.
Joel Kuula, Hilkka Timonen, Jarkko V. Niemi, Hanna E. Manninen, Topi Rönkkö, Tareq Hussein, Pak Lun Fung, Sasu Tarkoma, Mikko Laakso, Erkka Saukko, Aino Ovaska, Markku Kulmala, Ari Karppinen, Lasse Johansson, and Tuukka Petäjä
Atmos. Chem. Phys., 22, 4801–4808, https://doi.org/10.5194/acp-22-4801-2022, https://doi.org/10.5194/acp-22-4801-2022, 2022
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Modern and up-to-date policies and air quality management strategies are instrumental in tackling global air pollution. As the European Union is preparing to revise Ambient Air Quality Directive 2008/50/EC, this paper initiates discussion on selected features of the directive that we believe would benefit from a reassessment. The scientific community has the most recent and deepest understanding of air pollution; thus, its contribution is essential.
Mathew Sebastian, Sobhan Kumar Kompalli, Vasudevan Anil Kumar, Sandhya Jose, S. Suresh Babu, Govindan Pandithurai, Sachchidanand Singh, Rakesh K. Hooda, Vijay K. Soni, Jeffrey R. Pierce, Ville Vakkari, Eija Asmi, Daniel M. Westervelt, Antti-Pekka Hyvärinen, and Vijay P. Kanawade
Atmos. Chem. Phys., 22, 4491–4508, https://doi.org/10.5194/acp-22-4491-2022, https://doi.org/10.5194/acp-22-4491-2022, 2022
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Characteristics of particle number size distributions and new particle formation in six locations in India were analyzed. New particle formation occurred frequently during the pre-monsoon (spring) season and it significantly modulates the shape of the particle number size distributions. The contribution of newly formed particles to cloud condensation nuclei concentrations was ~3 times higher in urban locations than in mountain background locations.
Hanna K. Lappalainen, Tuukka Petäjä, Timo Vihma, Jouni Räisänen, Alexander Baklanov, Sergey Chalov, Igor Esau, Ekaterina Ezhova, Matti Leppäranta, Dmitry Pozdnyakov, Jukka Pumpanen, Meinrat O. Andreae, Mikhail Arshinov, Eija Asmi, Jianhui Bai, Igor Bashmachnikov, Boris Belan, Federico Bianchi, Boris Biskaborn, Michael Boy, Jaana Bäck, Bin Cheng, Natalia Chubarova, Jonathan Duplissy, Egor Dyukarev, Konstantinos Eleftheriadis, Martin Forsius, Martin Heimann, Sirkku Juhola, Vladimir Konovalov, Igor Konovalov, Pavel Konstantinov, Kajar Köster, Elena Lapshina, Anna Lintunen, Alexander Mahura, Risto Makkonen, Svetlana Malkhazova, Ivan Mammarella, Stefano Mammola, Stephany Buenrostro Mazon, Outi Meinander, Eugene Mikhailov, Victoria Miles, Stanislav Myslenkov, Dmitry Orlov, Jean-Daniel Paris, Roberta Pirazzini, Olga Popovicheva, Jouni Pulliainen, Kimmo Rautiainen, Torsten Sachs, Vladimir Shevchenko, Andrey Skorokhod, Andreas Stohl, Elli Suhonen, Erik S. Thomson, Marina Tsidilina, Veli-Pekka Tynkkynen, Petteri Uotila, Aki Virkkula, Nadezhda Voropay, Tobias Wolf, Sayaka Yasunaka, Jiahua Zhang, Yubao Qiu, Aijun Ding, Huadong Guo, Valery Bondur, Nikolay Kasimov, Sergej Zilitinkevich, Veli-Matti Kerminen, and Markku Kulmala
Atmos. Chem. Phys., 22, 4413–4469, https://doi.org/10.5194/acp-22-4413-2022, https://doi.org/10.5194/acp-22-4413-2022, 2022
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We summarize results during the last 5 years in the northern Eurasian region, especially from Russia, and introduce recent observations of the air quality in the urban environments in China. Although the scientific knowledge in these regions has increased, there are still gaps in our understanding of large-scale climate–Earth surface interactions and feedbacks. This arises from limitations in research infrastructures and integrative data analyses, hindering a comprehensive system analysis.
Lisa J. Beck, Siegfried Schobesberger, Mikko Sipilä, Veli-Matti Kerminen, and Markku Kulmala
Atmos. Meas. Tech., 15, 1957–1965, https://doi.org/10.5194/amt-15-1957-2022, https://doi.org/10.5194/amt-15-1957-2022, 2022
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Sulfuric acid is known to be a main compound in atmospheric new particle formation. Yet, its concentration is very low, which leads to challenges in detecting it. In our study, we derive the sulfuric acid concentration from measurements of ambient ions with a mass spectrometer. Our validation shows that the theoretical approach using the bisulfate ion and its clusters with H2SO4 captures the sulfuric acid concentration very well during daytime.
Marco A. Franco, Florian Ditas, Leslie A. Kremper, Luiz A. T. Machado, Meinrat O. Andreae, Alessandro Araújo, Henrique M. J. Barbosa, Joel F. de Brito, Samara Carbone, Bruna A. Holanda, Fernando G. Morais, Janaína P. Nascimento, Mira L. Pöhlker, Luciana V. Rizzo, Marta Sá, Jorge Saturno, David Walter, Stefan Wolff, Ulrich Pöschl, Paulo Artaxo, and Christopher Pöhlker
Atmos. Chem. Phys., 22, 3469–3492, https://doi.org/10.5194/acp-22-3469-2022, https://doi.org/10.5194/acp-22-3469-2022, 2022
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In Central Amazonia, new particle formation in the planetary boundary layer is rare. Instead, there is the appearance of sub-50 nm aerosols with diameters larger than about 20 nm that eventually grow to cloud condensation nuclei size range. Here, 254 growth events were characterized which have higher predominance in the wet season. About 70 % of them showed direct relation to convective downdrafts, while 30 % occurred partly under clear-sky conditions, evidencing still unknown particle sources.
Stephen M. Platt, Øystein Hov, Torunn Berg, Knut Breivik, Sabine Eckhardt, Konstantinos Eleftheriadis, Nikolaos Evangeliou, Markus Fiebig, Rebecca Fisher, Georg Hansen, Hans-Christen Hansson, Jost Heintzenberg, Ove Hermansen, Dominic Heslin-Rees, Kim Holmén, Stephen Hudson, Roland Kallenborn, Radovan Krejci, Terje Krognes, Steinar Larssen, David Lowry, Cathrine Lund Myhre, Chris Lunder, Euan Nisbet, Pernilla B. Nizzetto, Ki-Tae Park, Christina A. Pedersen, Katrine Aspmo Pfaffhuber, Thomas Röckmann, Norbert Schmidbauer, Sverre Solberg, Andreas Stohl, Johan Ström, Tove Svendby, Peter Tunved, Kjersti Tørnkvist, Carina van der Veen, Stergios Vratolis, Young Jun Yoon, Karl Espen Yttri, Paul Zieger, Wenche Aas, and Kjetil Tørseth
Atmos. Chem. Phys., 22, 3321–3369, https://doi.org/10.5194/acp-22-3321-2022, https://doi.org/10.5194/acp-22-3321-2022, 2022
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Here we detail the history of the Zeppelin Observatory, a unique global background site and one of only a few in the high Arctic. We present long-term time series of up to 30 years of atmospheric components and atmospheric transport phenomena. Many of these time series are important to our understanding of Arctic and global atmospheric composition change. Finally, we discuss the future of the Zeppelin Observatory and emerging areas of future research on the Arctic atmosphere.
Jingwei Zhang, Chaofan Lian, Weigang Wang, Maofa Ge, Yitian Guo, Haiyan Ran, Yusheng Zhang, Feixue Zheng, Xiaolong Fan, Chao Yan, Kaspar R. Daellenbach, Yongchun Liu, Markku Kulmala, and Junling An
Atmos. Chem. Phys., 22, 3275–3302, https://doi.org/10.5194/acp-22-3275-2022, https://doi.org/10.5194/acp-22-3275-2022, 2022
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This study added six potential HONO sources to the WRF-Chem model, evaluated their impact on HONO and O3 concentrations, including surface and vertical concentrations. The simulations extend our knowledge on atmospheric HONO sources, especially for nitrate photolysis. The study also explains the HONO difference in O3 formation on clean and hazy days, and reveals key potential HONO sources to O3 enhancements in haze-aggravating processes with a co-occurrence of high PM2.5 and O3 concentrations.
Marjan Marbouti, Sehyun Jang, Silvia Becagli, Gabriel Navarro, Rita Traversi, Kitack Lee, Tuomo Nieminen, Lisa J. Beck, Markku Kulmala, Veli-Matti Kerminen, and Mikko Sipilä
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-52, https://doi.org/10.5194/acp-2022-52, 2022
Publication in ACP not foreseen
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This research was done to understand and investigate the roles of Chl-a, PP and sea ice extent in controlling and producing the in-situ measured MSA, SA, HIO3, HOM and aerosol concentrations over the Greenland and Barents Seas. Our results provide strong support to the hypothesis that MSA, SA and small-particle concentrations in the Svalbard area are directly linked to ocean biological activity and sea ice melting during springtime.
Timo Vesala, Kukka-Maaria Kohonen, Linda M. J. Kooijmans, Arnaud P. Praplan, Lenka Foltýnová, Pasi Kolari, Markku Kulmala, Jaana Bäck, David Nelson, Dan Yakir, Mark Zahniser, and Ivan Mammarella
Atmos. Chem. Phys., 22, 2569–2584, https://doi.org/10.5194/acp-22-2569-2022, https://doi.org/10.5194/acp-22-2569-2022, 2022
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Carbonyl sulfide (COS) provides new insights into carbon cycle research. We present an easy-to-use flux parameterization and the longest existing time series of forest–atmosphere COS exchange measurements, which allow us to study both seasonal and interannual variability. We observed only uptake of COS by the forest on an annual basis, with 37 % variability between years. Upscaling the boreal COS uptake using a biosphere model indicates a significant missing COS sink at high latitudes.
Lu Chen, Fang Zhang, Don Collins, Jingye Ren, Jieyao Liu, Sihui Jiang, and Zhanqing Li
Atmos. Chem. Phys., 22, 2293–2307, https://doi.org/10.5194/acp-22-2293-2022, https://doi.org/10.5194/acp-22-2293-2022, 2022
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Understanding the volatility and mixing state of atmospheric aerosols is important for elucidating their formation. Here, the size-resolved volatility of fine particles is characterized using field measurements. On average, the particles are more volatile in the summer. The retrieved mixing state shows that black carbon (BC)-containing particles dominate and contribute 67–77 % toward the total number concentration in the winter, while the non-BC particles accounted for 52–69 % in the summer.
Tuija Jokinen, Katrianne Lehtipalo, Roseline Cutting Thakur, Ilona Ylivinkka, Kimmo Neitola, Nina Sarnela, Totti Laitinen, Markku Kulmala, Tuukka Petäjä, and Mikko Sipilä
Atmos. Chem. Phys., 22, 2237–2254, https://doi.org/10.5194/acp-22-2237-2022, https://doi.org/10.5194/acp-22-2237-2022, 2022
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New particle formation is an important source of cloud condensation nuclei; however, long-term measurements of aerosol-forming vapors are close to nonexistent in the Arctic. Here, we report 7 months of CI-APi-TOF measurements of sulfuric acid, iodic acid, methane sulfonic acid and the sum of highly oxygenated organic molecules from the SMEAR I station in the Finnish subarctic. The results help us to understand atmospheric chemical processes and aerosol formation in this rapidly changing area.
Konstantinos Matthaios Doulgeris, Heikki Lihavainen, Anti-Pekka Hyvärinen, Veli-Matti Kerminen, and David Brus
Earth Syst. Sci. Data, 14, 637–649, https://doi.org/10.5194/essd-14-637-2022, https://doi.org/10.5194/essd-14-637-2022, 2022
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We produced and summarized data sets obtained from two cloud ground-based spectrometers (CAPS and FSSP-100 ground setups) during 8 years of Pallas Cloud Experiment campaigns conducted in autumn from 2004 until 2019 along with several meteorological variables. The campaigns took place in the Finnish sub-Arctic region in a clear environment in temperatures that were usually below zero. This data set provides a helpful contribution to cloud microphysics processes.
Pak Lun Fung, Martha A. Zaidan, Jarkko V. Niemi, Erkka Saukko, Hilkka Timonen, Anu Kousa, Joel Kuula, Topi Rönkkö, Ari Karppinen, Sasu Tarkoma, Markku Kulmala, Tuukka Petäjä, and Tareq Hussein
Atmos. Chem. Phys., 22, 1861–1882, https://doi.org/10.5194/acp-22-1861-2022, https://doi.org/10.5194/acp-22-1861-2022, 2022
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We developed an input-adaptive mixed-effects model, which was automatised to select the best combination of input variables, including up to three fixed effect variables and three time indictors as random effect variables. We tested the model to estimate lung-deposited surface area (LDSA), which correlates well with human health. The results show the inclusion of time indicators improved the sensitivity and the accuracy of the model so that it could serve as a network of virtual sensors.
Yingze Tian, Xiaoning Wang, Peng Zhao, Zongbo Shi, and Roy M. Harrison
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-1007, https://doi.org/10.5194/acp-2021-1007, 2022
Revised manuscript not accepted
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Chemical mass balance (CMB) is a widely used method to apportion the sources of PM2.5. We explore the sensitivity of CMB results to input data of organic markers only (OM-CMB) with a combination of organic and inorganic markers (IOM-CMB), as well as using different chemical profiles for sources. Our results indicate the superiority of combining inorganic and organic tracers and using locally-relevant source profiles in source apportionment of PM.
Kimmo Korhonen, Thomas Bjerring Kristensen, John Falk, Vilhelm B. Malmborg, Axel Eriksson, Louise Gren, Maja Novakovic, Sam Shamun, Panu Karjalainen, Lassi Markkula, Joakim Pagels, Birgitta Svenningsson, Martin Tunér, Mika Komppula, Ari Laaksonen, and Annele Virtanen
Atmos. Chem. Phys., 22, 1615–1631, https://doi.org/10.5194/acp-22-1615-2022, https://doi.org/10.5194/acp-22-1615-2022, 2022
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We investigated the ice-nucleating abilities of particulate emissions from a modern diesel engine using the portable ice-nuclei counter SPIN, a continuous-flow diffusion chamber instrument. Three different fuels were studied without blending, including fossil diesel and two renewable fuels, testing different emission aftertreatment systems and photochemical aging. We found that the diesel emissions were inefficient ice nuclei, and aging had no or little effect on their ice-nucleating abilities.
Daniel M. Kalbermatter, Griša Močnik, Luka Drinovec, Bradley Visser, Jannis Röhrbein, Matthias Oscity, Ernest Weingartner, Antti-Pekka Hyvärinen, and Konstantina Vasilatou
Atmos. Meas. Tech., 15, 561–572, https://doi.org/10.5194/amt-15-561-2022, https://doi.org/10.5194/amt-15-561-2022, 2022
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Soot particles with varying amounts of secondary organic matter coating were generated and used to compare a series of aerosol-absorption-measuring instruments: filter-based and photoacoustic instruments as well as photo-thermal interferometers. Significant deviations in the response of the instruments were observed depending on the amount of secondary organic coating. The system can be used for the inter-comparison and characterisation of instruments.
Jing Cai, Cheng Wu, Jiandong Wang, Wei Du, Feixue Zheng, Simo Hakala, Xiaolong Fan, Biwu Chu, Lei Yao, Zemin Feng, Yongchun Liu, Yele Sun, Jun Zheng, Chao Yan, Federico Bianchi, Markku Kulmala, Claudia Mohr, and Kaspar R. Daellenbach
Atmos. Chem. Phys., 22, 1251–1269, https://doi.org/10.5194/acp-22-1251-2022, https://doi.org/10.5194/acp-22-1251-2022, 2022
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This study investigates the connection between organic aerosol (OA) molecular composition and particle absorptive properties in autumn in Beijing. We find that the molecular properties of OA compounds in different episodes influence particle light absorption properties differently: the light absorption enhancement of black carbon and light absorption coefficient of brown carbon were mostly related to more oxygenated OA (low C number and four O atoms) and aromatics/nitro-aromatics, respectively.
Peifeng Su, Jorma Joutsensaari, Lubna Dada, Martha Arbayani Zaidan, Tuomo Nieminen, Xinyang Li, Yusheng Wu, Stefano Decesari, Sasu Tarkoma, Tuukka Petäjä, Markku Kulmala, and Petri Pellikka
Atmos. Chem. Phys., 22, 1293–1309, https://doi.org/10.5194/acp-22-1293-2022, https://doi.org/10.5194/acp-22-1293-2022, 2022
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We regarded the banana shapes in the surface plots as a special kind of object (similar to cats) and applied an instance segmentation technique to automatically identify the new particle formation (NPF) events (especially the strongest ones), in addition to their growth rates, start times, and end times. The automatic method generalized well on datasets collected in different sites, which is useful for long-term data series analysis and obtaining statistical properties of NPF events.
Jutta Kesti, John Backman, Ewan J. O'Connor, Anne Hirsikko, Eija Asmi, Minna Aurela, Ulla Makkonen, Maria Filioglou, Mika Komppula, Hannele Korhonen, and Heikki Lihavainen
Atmos. Chem. Phys., 22, 481–503, https://doi.org/10.5194/acp-22-481-2022, https://doi.org/10.5194/acp-22-481-2022, 2022
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In this study we combined aerosol particle measurements at the surface with a scanning Doppler lidar providing vertical profiles of the atmosphere to study the effect of different boundary layer conditions on aerosol particle properties in the understudied Arabian Peninsula region. The instrumentation used in this study enabled us to identify periods when pollution from remote sources was mixed down to the surface and initiated new particle formation in the growing boundary layer.
Arto Heitto, Kari Lehtinen, Tuukka Petäjä, Felipe Lopez-Hilfiker, Joel A. Thornton, Markku Kulmala, and Taina Yli-Juuti
Atmos. Chem. Phys., 22, 155–171, https://doi.org/10.5194/acp-22-155-2022, https://doi.org/10.5194/acp-22-155-2022, 2022
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For atmospheric aerosol particles to take part in cloud formation, they need to be at least a few tens of nanometers in diameter. By using a particle condensation model, we investigated how two types of chemical reactions, oligomerization and decomposition, of organic molecules inside the particle may affect the growth of secondary aerosol particles to these sizes. We show that the effect is potentially significant, which highlights the importance of increasing understanding of these processes.
Lukas Fischer, Martin Breitenlechner, Eva Canaval, Wiebke Scholz, Marcus Striednig, Martin Graus, Thomas G. Karl, Tuukka Petäjä, Markku Kulmala, and Armin Hansel
Atmos. Meas. Tech., 14, 8019–8039, https://doi.org/10.5194/amt-14-8019-2021, https://doi.org/10.5194/amt-14-8019-2021, 2021
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Ecosystems emit biogenic volatile organic compounds (BVOCs), which are then oxidized in the atmosphere, contributing to ozone and secondary aerosol formation. While flux measurements of BVOCs are state of the art, flux measurements of the less volatile oxidation products are difficult to achieve due to inlet losses. Here we present first flux measurements, utilizing a novel PTR3 instrument in combination with a specially designed wall-less inlet we put on top of the Hyytiälä tower in Finland.
Luiz A. T. Machado, Marco A. Franco, Leslie A. Kremper, Florian Ditas, Meinrat O. Andreae, Paulo Artaxo, Micael A. Cecchini, Bruna A. Holanda, Mira L. Pöhlker, Ivan Saraiva, Stefan Wolff, Ulrich Pöschl, and Christopher Pöhlker
Atmos. Chem. Phys., 21, 18065–18086, https://doi.org/10.5194/acp-21-18065-2021, https://doi.org/10.5194/acp-21-18065-2021, 2021
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Several studies evaluate aerosol–cloud interactions, but only a few attempted to describe how clouds modify aerosol properties. This study evaluates the effect of weather events on the particle size distribution at the ATTO, combining remote sensing and in situ data. Ultrafine, Aitken and accumulation particles modes have different behaviors for the diurnal cycle and for rainfall events. This study opens up new scientific questions that need to be pursued in detail in new field campaigns.
Ying Zhou, Simo Hakala, Chao Yan, Yang Gao, Xiaohong Yao, Biwu Chu, Tommy Chan, Juha Kangasluoma, Shahzad Gani, Jenni Kontkanen, Pauli Paasonen, Yongchun Liu, Tuukka Petäjä, Markku Kulmala, and Lubna Dada
Atmos. Chem. Phys., 21, 17885–17906, https://doi.org/10.5194/acp-21-17885-2021, https://doi.org/10.5194/acp-21-17885-2021, 2021
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We characterized the connection between new particle formation (NPF) events in terms of frequency, intensity and growth at a near-highway location in central Beijing and at a background mountain site 80 km away. Due to the substantial contribution of NPF to the global aerosol budget, identifying the conditions that promote the occurrence of regional NPF events could help understand their contribution on a large scale and would improve their implementation in global models.
Irini Tsiodra, Georgios Grivas, Kalliopi Tavernaraki, Aikaterini Bougiatioti, Maria Apostolaki, Despina Paraskevopoulou, Alexandra Gogou, Constantine Parinos, Konstantina Oikonomou, Maria Tsagkaraki, Pavlos Zarmpas, Athanasios Nenes, and Nikolaos Mihalopoulos
Atmos. Chem. Phys., 21, 17865–17883, https://doi.org/10.5194/acp-21-17865-2021, https://doi.org/10.5194/acp-21-17865-2021, 2021
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We analyze observations from year-long measurements at Athens, Greece. Nighttime wintertime PAH levels are 4 times higher than daytime, and wintertime values are 15 times higher than summertime. Biomass burning aerosol during wintertime pollution events is responsible for these significant wintertime enhancements and accounts for 43 % of the population exposure to PAH carcinogenic risk. Biomass burning poses additional health risks beyond those associated with the high PM levels that develop.
Moritz Lange, Henri Suominen, Mona Kurppa, Leena Järvi, Emilia Oikarinen, Rafael Savvides, and Kai Puolamäki
Geosci. Model Dev., 14, 7411–7424, https://doi.org/10.5194/gmd-14-7411-2021, https://doi.org/10.5194/gmd-14-7411-2021, 2021
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This study aims to replicate computationally expensive high-resolution large-eddy simulations (LESs) with regression models to simulate urban air quality and pollutant dispersion. The model development, including feature selection, model training and cross-validation, and detection of concept drift, has been described in detail. Of the models applied, log-linear regression shows the best performance. A regression model can replace LES unless high accuracy is needed.
Mikko Sipilä, Nina Sarnela, Kimmo Neitola, Totti Laitinen, Deniz Kemppainen, Lisa Beck, Ella-Maria Duplissy, Salla Kuittinen, Tuuli Lehmusjärvi, Janne Lampilahti, Veli-Matti Kerminen, Katrianne Lehtipalo, Pasi P. Aalto, Petri Keronen, Erkki Siivola, Pekka A. Rantala, Douglas R. Worsnop, Markku Kulmala, Tuija Jokinen, and Tuukka Petäjä
Atmos. Chem. Phys., 21, 17559–17576, https://doi.org/10.5194/acp-21-17559-2021, https://doi.org/10.5194/acp-21-17559-2021, 2021
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Metallurgical industry in Kola peninsula is a large source of air pollution in the (sub-)Arctic domain. Sulfur dioxide emissions from the ore smelters are transported across large areas. We investigated sulfur dioxide and its transformation to sulfuric acid aerosol particles during winter months in Finnish Lapland, close to Kola industrial areas. We observed intense formation of new aerosol particles despite the low solar radiation intensity, often required for new particle formation elsewhere.
Ramon Campos Braga, Barbara Ervens, Daniel Rosenfeld, Meinrat O. Andreae, Jan-David Förster, Daniel Fütterer, Lianet Hernández Pardo, Bruna A. Holanda, Tina Jurkat-Witschas, Ovid O. Krüger, Oliver Lauer, Luiz A. T. Machado, Christopher Pöhlker, Daniel Sauer, Christiane Voigt, Adrian Walser, Manfred Wendisch, Ulrich Pöschl, and Mira L. Pöhlker
Atmos. Chem. Phys., 21, 17513–17528, https://doi.org/10.5194/acp-21-17513-2021, https://doi.org/10.5194/acp-21-17513-2021, 2021
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Interactions of aerosol particles with clouds represent a large uncertainty in estimates of climate change. Properties of aerosol particles control their ability to act as cloud condensation nuclei. Using aerosol measurements in the Amazon, we performed model studies to compare predicted and measured cloud droplet number concentrations at cloud bases. Our results confirm previous estimates of particle hygroscopicity in this region.
Ditte Taipale, Veli-Matti Kerminen, Mikael Ehn, Markku Kulmala, and Ülo Niinemets
Atmos. Chem. Phys., 21, 17389–17431, https://doi.org/10.5194/acp-21-17389-2021, https://doi.org/10.5194/acp-21-17389-2021, 2021
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Larval feeding and fungal infections of leaves can greatly change the emission of volatile compounds from plants and thereby influence aerosol processes in the air. We developed a model that considers the dynamics of larvae and fungi and the dependency of the emission on the severity of stress. We show that the infections can be highly atmospherically relevant during long periods of time and at times more important to consider than the parameters that are currently used in emission models.
Clémence Rose, Martine Collaud Coen, Elisabeth Andrews, Yong Lin, Isaline Bossert, Cathrine Lund Myhre, Thomas Tuch, Alfred Wiedensohler, Markus Fiebig, Pasi Aalto, Andrés Alastuey, Elisabeth Alonso-Blanco, Marcos Andrade, Begoña Artíñano, Todor Arsov, Urs Baltensperger, Susanne Bastian, Olaf Bath, Johan Paul Beukes, Benjamin T. Brem, Nicolas Bukowiecki, Juan Andrés Casquero-Vera, Sébastien Conil, Konstantinos Eleftheriadis, Olivier Favez, Harald Flentje, Maria I. Gini, Francisco Javier Gómez-Moreno, Martin Gysel-Beer, Anna Gannet Hallar, Ivo Kalapov, Nikos Kalivitis, Anne Kasper-Giebl, Melita Keywood, Jeong Eun Kim, Sang-Woo Kim, Adam Kristensson, Markku Kulmala, Heikki Lihavainen, Neng-Huei Lin, Hassan Lyamani, Angela Marinoni, Sebastiao Martins Dos Santos, Olga L. Mayol-Bracero, Frank Meinhardt, Maik Merkel, Jean-Marc Metzger, Nikolaos Mihalopoulos, Jakub Ondracek, Marco Pandolfi, Noemi Pérez, Tuukka Petäjä, Jean-Eudes Petit, David Picard, Jean-Marc Pichon, Veronique Pont, Jean-Philippe Putaud, Fabienne Reisen, Karine Sellegri, Sangeeta Sharma, Gerhard Schauer, Patrick Sheridan, James Patrick Sherman, Andreas Schwerin, Ralf Sohmer, Mar Sorribas, Junying Sun, Pierre Tulet, Ville Vakkari, Pieter Gideon van Zyl, Fernando Velarde, Paolo Villani, Stergios Vratolis, Zdenek Wagner, Sheng-Hsiang Wang, Kay Weinhold, Rolf Weller, Margarita Yela, Vladimir Zdimal, and Paolo Laj
Atmos. Chem. Phys., 21, 17185–17223, https://doi.org/10.5194/acp-21-17185-2021, https://doi.org/10.5194/acp-21-17185-2021, 2021
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Aerosol particles are a complex component of the atmospheric system the effects of which are among the most uncertain in climate change projections. Using data collected at 62 stations, this study provides the most up-to-date picture of the spatial distribution of particle number concentration and size distribution worldwide, with the aim of contributing to better representation of aerosols and their interactions with clouds in models and, therefore, better evaluation of their impact on climate.
Lucía Caudillo, Birte Rörup, Martin Heinritzi, Guillaume Marie, Mario Simon, Andrea C. Wagner, Tatjana Müller, Manuel Granzin, Antonio Amorim, Farnoush Ataei, Rima Baalbaki, Barbara Bertozzi, Zoé Brasseur, Randall Chiu, Biwu Chu, Lubna Dada, Jonathan Duplissy, Henning Finkenzeller, Loïc Gonzalez Carracedo, Xu-Cheng He, Victoria Hofbauer, Weimeng Kong, Houssni Lamkaddam, Chuan P. Lee, Brandon Lopez, Naser G. A. Mahfouz, Vladimir Makhmutov, Hanna E. Manninen, Ruby Marten, Dario Massabò, Roy L. Mauldin, Bernhard Mentler, Ugo Molteni, Antti Onnela, Joschka Pfeifer, Maxim Philippov, Ana A. Piedehierro, Meredith Schervish, Wiebke Scholz, Benjamin Schulze, Jiali Shen, Dominik Stolzenburg, Yuri Stozhkov, Mihnea Surdu, Christian Tauber, Yee Jun Tham, Ping Tian, António Tomé, Steffen Vogt, Mingyi Wang, Dongyu S. Wang, Stefan K. Weber, André Welti, Wang Yonghong, Wu Yusheng, Marcel Zauner-Wieczorek, Urs Baltensperger, Imad El Haddad, Richard C. Flagan, Armin Hansel, Kristina Höhler, Jasper Kirkby, Markku Kulmala, Katrianne Lehtipalo, Ottmar Möhler, Harald Saathoff, Rainer Volkamer, Paul M. Winkler, Neil M. Donahue, Andreas Kürten, and Joachim Curtius
Atmos. Chem. Phys., 21, 17099–17114, https://doi.org/10.5194/acp-21-17099-2021, https://doi.org/10.5194/acp-21-17099-2021, 2021
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We performed experiments in the CLOUD chamber at CERN at low temperatures to simulate new particle formation in the upper free troposphere (at −30 ºC and −50 ºC). We measured the particle and gas phase and found that most of the compounds present in the gas phase are detected as well in the particle phase. The major compounds in the particles are C8–10 and C18–20. Specifically, we showed that C5 and C15 compounds are detected in a mixed system with isoprene and α-pinene at −30 ºC, 20 % RH.
Anna Franck, Dmitri Moisseev, Ville Vakkari, Matti Leskinen, Janne Lampilahti, Veli-Matti Kerminen, and Ewan O'Connor
Atmos. Meas. Tech., 14, 7341–7353, https://doi.org/10.5194/amt-14-7341-2021, https://doi.org/10.5194/amt-14-7341-2021, 2021
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We proposed a method to derive a convective boundary layer height, using insects in radar observations, and we investigated the consistency of these retrievals among different radar frequencies (5, 35 and 94 GHz). This method can be applied to radars at other measurement stations and serve as additional way to estimate the boundary layer height during summer. The entrainment zone was also observed by the 5 GHz radar above the boundary layer in the form of a Bragg scatter layer.
Terhi K. Laurila, Hilppa Gregow, Joona Cornér, and Victoria A. Sinclair
Weather Clim. Dynam., 2, 1111–1130, https://doi.org/10.5194/wcd-2-1111-2021, https://doi.org/10.5194/wcd-2-1111-2021, 2021
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We create a climatology of mid-latitude cyclones and windstorms in northern Europe and investigate how sensitive the minimum pressure and maximum gust of windstorms are to four precursors. Windstorms are more common in the cold season than the warm season, whereas the number of mid-latitude cyclones has no annual cycle. The low-level temperature gradient has the strongest impact of all considered precursors on the intensity of windstorms in terms of both the minimum pressure and maximum gust.
Martti Honkanen, Jens Daniel Müller, Jukka Seppälä, Gregor Rehder, Sami Kielosto, Pasi Ylöstalo, Timo Mäkelä, Juha Hatakka, and Lauri Laakso
Ocean Sci., 17, 1657–1675, https://doi.org/10.5194/os-17-1657-2021, https://doi.org/10.5194/os-17-1657-2021, 2021
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The exchange of carbon dioxide (CO2) between the sea and the atmosphere is regulated by the gradient of CO2 partial pressure (pCO2) between the sea and the air. The daily variation of the seawater pCO2 recorded at the fixed station Utö in the Baltic Sea was found to be mainly biologically driven. Calculation of the annual net exchange of CO2 between the sea and atmosphere based on daily measurements of pCO2 carried out using the same sampling time every day could introduce a bias of up to 12 %.
Sebastian Düsing, Albert Ansmann, Holger Baars, Joel C. Corbin, Cyrielle Denjean, Martin Gysel-Beer, Thomas Müller, Laurent Poulain, Holger Siebert, Gerald Spindler, Thomas Tuch, Birgit Wehner, and Alfred Wiedensohler
Atmos. Chem. Phys., 21, 16745–16773, https://doi.org/10.5194/acp-21-16745-2021, https://doi.org/10.5194/acp-21-16745-2021, 2021
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The work deals with optical properties of aerosol particles in dried and atmospheric states. Based on two measurement campaigns in the rural background of central Europe, different measurement approaches were compared with each other, such as modeling based on Mie theory and direct in situ or remote sensing measurements. Among others, it was shown that the aerosol extinction-to-backscatter ratio is relative humidity dependent, and refinement with respect to the model input parameters is needed.
Diego Aliaga, Victoria A. Sinclair, Marcos Andrade, Paulo Artaxo, Samara Carbone, Evgeny Kadantsev, Paolo Laj, Alfred Wiedensohler, Radovan Krejci, and Federico Bianchi
Atmos. Chem. Phys., 21, 16453–16477, https://doi.org/10.5194/acp-21-16453-2021, https://doi.org/10.5194/acp-21-16453-2021, 2021
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We investigate the origin of air masses sampled at Mount Chacaltaya, Bolivia. Three-quarters of the measured air has not been influenced by the surface in the previous 4 d. However, it is rare that, at any given time, the sampled air has not been influenced at all by the surface, and often the sampled air has multiple origins. The influence of the surface is more prevalent during day than night. Furthermore, during the 6-month study, one-third of the air masses originated from Amazonia.
Najin Kim, Yafang Cheng, Nan Ma, Mira L. Pöhlker, Thomas Klimach, Thomas F. Mentel, Ovid O. Krüger, Ulrich Pöschl, and Hang Su
Atmos. Meas. Tech., 14, 6991–7005, https://doi.org/10.5194/amt-14-6991-2021, https://doi.org/10.5194/amt-14-6991-2021, 2021
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A broad supersaturation scanning CCN (BS2-CCN) system, in which particles are exposed to a range of supersaturation simultaneously, can measure a broad range of CCN activity distribution with a high time resolution. We describe how the BS2-CCN system can be effectively calibrated and which factors can affect the calibration curve. Intercomparison experiments between typical DMA-CCN and BS2-CCN measurements to evaluate the BS2-CCN system showed high correlation and good agreement.
Shahzad Gani, Lukas Kohl, Rima Baalbaki, Federico Bianchi, Taina M. Ruuskanen, Olli-Pekka Siira, Pauli Paasonen, and Hanna Vehkamäki
Geosci. Commun., 4, 507–516, https://doi.org/10.5194/gc-4-507-2021, https://doi.org/10.5194/gc-4-507-2021, 2021
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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.
Chunshui Lin, Darius Ceburnis, Anna Trubetskaya, Wei Xu, William Smith, Stig Hellebust, John Wenger, Colin O'Dowd, and Jurgita Ovadnevaite
Atmos. Meas. Tech., 14, 6905–6916, https://doi.org/10.5194/amt-14-6905-2021, https://doi.org/10.5194/amt-14-6905-2021, 2021
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Source apportionment of solid-fuel-burning emissions can be complicated by the use of different fuels, stoves, and burning conditions. Here, the organic aerosol mass spectra produced from burning a range of solid fuels in several stoves were compared. This study accounts for the source variability and provides better constraints on the primary factor contributions to the ambient organic aerosol estimations, holding significant implications for public health and policymakers.
Sho Ohata, Tatsuhiro Mori, Yutaka Kondo, Sangeeta Sharma, Antti Hyvärinen, Elisabeth Andrews, Peter Tunved, Eija Asmi, John Backman, Henri Servomaa, Daniel Veber, Konstantinos Eleftheriadis, Stergios Vratolis, Radovan Krejci, Paul Zieger, Makoto Koike, Yugo Kanaya, Atsushi Yoshida, Nobuhiro Moteki, Yongjing Zhao, Yutaka Tobo, Junji Matsushita, and Naga Oshima
Atmos. Meas. Tech., 14, 6723–6748, https://doi.org/10.5194/amt-14-6723-2021, https://doi.org/10.5194/amt-14-6723-2021, 2021
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Reliable values of mass absorption cross sections (MACs) of black carbon (BC) are required to determine mass concentrations of BC at Arctic sites using different types of filter-based absorption photometers. We successfully estimated MAC values for these instruments through comparison with independent measurements of BC by a continuous soot monitoring system called COSMOS. These MAC values are consistent with each other and applicable to study spatial and temporal variation in BC in the Arctic.
Krista Luoma, Aki Virkkula, Pasi Aalto, Katrianne Lehtipalo, Tuukka Petäjä, and Markku Kulmala
Atmos. Meas. Tech., 14, 6419–6441, https://doi.org/10.5194/amt-14-6419-2021, https://doi.org/10.5194/amt-14-6419-2021, 2021
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The study presents a comparison of three absorption photometers that measured ambient aerosol particles at a boreal forest site. The study aims to better understand problems related to filter-based measurements. Results show how different correction algorithms, which are used to produce the data, affect the derived optical properties of aerosol particles.
Yuliang Liu, Wei Nie, Yuanyuan Li, Dafeng Ge, Chong Liu, Zhengning Xu, Liangduo Chen, Tianyi Wang, Lei Wang, Peng Sun, Ximeng Qi, Jiaping Wang, Zheng Xu, Jian Yuan, Chao Yan, Yanjun Zhang, Dandan Huang, Zhe Wang, Neil M. Donahue, Douglas Worsnop, Xuguang Chi, Mikael Ehn, and Aijun Ding
Atmos. Chem. Phys., 21, 14789–14814, https://doi.org/10.5194/acp-21-14789-2021, https://doi.org/10.5194/acp-21-14789-2021, 2021
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Oxygenated organic molecules (OOMs) are crucial intermediates linking volatile organic compounds to secondary organic aerosols. Using nitrate time-of-flight chemical ionization mass spectrometry in eastern China, we performed positive matrix factorization (PMF) on binned OOM mass spectra. We reconstructed over 1000 molecules from 14 derived PMF factors and identified about 72 % of the observed OOMs as organic nitrates, highlighting the decisive role of NOx in OOM formation in populated areas.
Deepchandra Srivastava, Jingsha Xu, Tuan V. Vu, Di Liu, Linjie Li, Pingqing Fu, Siqi Hou, Natalia Moreno Palmerola, Zongbo Shi, and Roy M. Harrison
Atmos. Chem. Phys., 21, 14703–14724, https://doi.org/10.5194/acp-21-14703-2021, https://doi.org/10.5194/acp-21-14703-2021, 2021
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This study presents the source apportionment of PM2.5 performed by positive matrix factorization (PMF) at urban and rural sites in Beijing. These factors are interpreted as traffic emissions, biomass burning, road and soil dust, coal and oil combustion, and secondary inorganics. PMF failed to resolve some sources identified by CMB and AMS and appears to overestimate the dust sources. Comparison with earlier PMF studies from the Beijing area highlights inconsistent findings using this method.
Haoran Li, Ottmar Möhler, Tuukka Petäjä, and Dmitri Moisseev
Atmos. Chem. Phys., 21, 14671–14686, https://doi.org/10.5194/acp-21-14671-2021, https://doi.org/10.5194/acp-21-14671-2021, 2021
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In natural clouds, ice-nucleating particles are expected to be rare above –10 °C. In the current paper, we found that the formation of ice columns is frequent in stratiform clouds and is associated with increased precipitation intensity and liquid water path. In single-layer shallow clouds, the production of ice columns was attributed to secondary ice production, despite the rime-splintering process not being expected to take place in such clouds.
Philipp G. Eger, Luc Vereecken, Rolf Sander, Jan Schuladen, Nicolas Sobanski, Horst Fischer, Einar Karu, Jonathan Williams, Ville Vakkari, Tuukka Petäjä, Jos Lelieveld, Andrea Pozzer, and John N. Crowley
Atmos. Chem. Phys., 21, 14333–14349, https://doi.org/10.5194/acp-21-14333-2021, https://doi.org/10.5194/acp-21-14333-2021, 2021
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We determine the impact of pyruvic acid photolysis on the formation of acetaldehyde and peroxy radicals during summer and autumn in the Finnish boreal forest using a data-constrained box model. Our results are dependent on the chosen scenario in which the overall quantum yield and the photolysis products are varied. We highlight that pyruvic acid photolysis can be an important contributor to acetaldehyde and peroxy radical formation in remote, forested regions.
Mao Xiao, Christopher R. Hoyle, Lubna Dada, Dominik Stolzenburg, Andreas Kürten, Mingyi Wang, Houssni Lamkaddam, Olga Garmash, Bernhard Mentler, Ugo Molteni, Andrea Baccarini, Mario Simon, Xu-Cheng He, Katrianne Lehtipalo, Lauri R. Ahonen, Rima Baalbaki, Paulus S. Bauer, Lisa Beck, David Bell, Federico Bianchi, Sophia Brilke, Dexian Chen, Randall Chiu, António Dias, Jonathan Duplissy, Henning Finkenzeller, Hamish Gordon, Victoria Hofbauer, Changhyuk Kim, Theodore K. Koenig, Janne Lampilahti, Chuan Ping Lee, Zijun Li, Huajun Mai, Vladimir Makhmutov, Hanna E. Manninen, Ruby Marten, Serge Mathot, Roy L. Mauldin, Wei Nie, Antti Onnela, Eva Partoll, Tuukka Petäjä, Joschka Pfeifer, Veronika Pospisilova, Lauriane L. J. Quéléver, Matti Rissanen, Siegfried Schobesberger, Simone Schuchmann, Yuri Stozhkov, Christian Tauber, Yee Jun Tham, António Tomé, Miguel Vazquez-Pufleau, Andrea C. Wagner, Robert Wagner, Yonghong Wang, Lena Weitz, Daniela Wimmer, Yusheng Wu, Chao Yan, Penglin Ye, Qing Ye, Qiaozhi Zha, Xueqin Zhou, Antonio Amorim, Ken Carslaw, Joachim Curtius, Armin Hansel, Rainer Volkamer, Paul M. Winkler, Richard C. Flagan, Markku Kulmala, Douglas R. Worsnop, Jasper Kirkby, Neil M. Donahue, Urs Baltensperger, Imad El Haddad, and Josef Dommen
Atmos. Chem. Phys., 21, 14275–14291, https://doi.org/10.5194/acp-21-14275-2021, https://doi.org/10.5194/acp-21-14275-2021, 2021
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Experiments at CLOUD show that in polluted environments new particle formation (NPF) is largely driven by the formation of sulfuric acid–base clusters, stabilized by amines, high ammonia concentrations or lower temperatures. While oxidation products of aromatics can nucleate, they play a minor role in urban NPF. Our experiments span 4 orders of magnitude variation of observed NPF rates in ambient conditions. We provide a framework based on NPF and growth rates to interpret ambient observations.
Ramon Campos Braga, Daniel Rosenfeld, Ovid O. Krüger, Barbara Ervens, Bruna A. Holanda, Manfred Wendisch, Trismono Krisna, Ulrich Pöschl, Meinrat O. Andreae, Christiane Voigt, and Mira L. Pöhlker
Atmos. Chem. Phys., 21, 14079–14088, https://doi.org/10.5194/acp-21-14079-2021, https://doi.org/10.5194/acp-21-14079-2021, 2021
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Quantifying the precipitation within clouds is crucial for our understanding of the Earth's hydrological cycle. Using in situ measurements of cloud and rain properties over the Amazon Basin and Atlantic Ocean, we show here a linear relationship between the effective radius (re) and precipitation water content near the tops of convective clouds for different pollution states and temperature levels. Our results emphasize the role of re to determine both initiation and amount of precipitation.
Christoffer Hallgren, Stefan Ivanell, Heiner Körnich, Ville Vakkari, and Erik Sahlée
Wind Energ. Sci., 6, 1205–1226, https://doi.org/10.5194/wes-6-1205-2021, https://doi.org/10.5194/wes-6-1205-2021, 2021
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As wind power becomes more popular, there is a growing demand for accurate power production forecasts. In this paper we investigated different methods to improve wind power forecasts for an offshore location in the Baltic Sea, using both simple and more advanced techniques. The performance of the methods is evaluated for different weather conditions. Smoothing the forecast was found to be the best method in general, but we recommend selecting which method to use based on the forecasted weather.
Yongchun Liu, Zemin Feng, Feixue Zheng, Xiaolei Bao, Pengfei Liu, Yanli Ge, Yan Zhao, Tao Jiang, Yunwen Liao, Yusheng Zhang, Xiaolong Fan, Chao Yan, Biwu Chu, Yonghong Wang, Wei Du, Jing Cai, Federico Bianchi, Tuukka Petäjä, Yujing Mu, Hong He, and Markku Kulmala
Atmos. Chem. Phys., 21, 13269–13286, https://doi.org/10.5194/acp-21-13269-2021, https://doi.org/10.5194/acp-21-13269-2021, 2021
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The mechanisms and kinetics of particulate sulfate formation in the atmosphere are still open questions although they have been extensively discussed. We found that uptake of SO2 is the rate-determining step for the conversion of SO2 to particulate sulfate. NH4NO3 plays an important role in AWC, the phase state of aerosol particles, and subsequently the uptake kinetics of SO2 under high-RH conditions. This work is a good example of the feedback between aerosol physics and aerosol chemistry.
Maria Prass, Meinrat O. Andreae, Alessandro C. de Araùjo, Paulo Artaxo, Florian Ditas, Wolfgang Elbert, Jan-David Förster, Marco Aurélio Franco, Isabella Hrabe de Angelis, Jürgen Kesselmeier, Thomas Klimach, Leslie Ann Kremper, Eckhard Thines, David Walter, Jens Weber, Bettina Weber, Bernhard M. Fuchs, Ulrich Pöschl, and Christopher Pöhlker
Biogeosciences, 18, 4873–4887, https://doi.org/10.5194/bg-18-4873-2021, https://doi.org/10.5194/bg-18-4873-2021, 2021
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Bioaerosols in the atmosphere over the Amazon rain forest were analyzed by molecular biological staining and microscopy. Eukaryotic, bacterial, and archaeal aerosols were quantified in time series and altitude profiles which exhibited clear differences in number concentrations and vertical distributions. Our results provide insights into the sources and dispersion of different Amazonian bioaerosol types as a basis for a better understanding of biosphere–atmosphere interactions.
Gloria Titos, María A. Burgos, Paul Zieger, Lucas Alados-Arboledas, Urs Baltensperger, Anne Jefferson, James Sherman, Ernest Weingartner, Bas Henzing, Krista Luoma, Colin O'Dowd, Alfred Wiedensohler, and Elisabeth Andrews
Atmos. Chem. Phys., 21, 13031–13050, https://doi.org/10.5194/acp-21-13031-2021, https://doi.org/10.5194/acp-21-13031-2021, 2021
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This paper investigates the impact of water uptake on aerosol optical properties, in particular the aerosol light-scattering coefficient. Although in situ measurements are performed at low relative humidity (typically at
RH < 40 %), to address the climatic impact of aerosol particles it is necessary to take into account the effect that water uptake may have on the aerosol optical properties.
Baseerat Romshoo, Thomas Müller, Sascha Pfeifer, Jorge Saturno, Andreas Nowak, Krzysztof Ciupek, Paul Quincey, and Alfred Wiedensohler
Atmos. Chem. Phys., 21, 12989–13010, https://doi.org/10.5194/acp-21-12989-2021, https://doi.org/10.5194/acp-21-12989-2021, 2021
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Modifications in the optical properties of black carbon (BC) due to ageing are presented and quantified in this study using a state-of-the-art description scheme of BC fractal aggregates. It is shown that the relative change in BC radiative forcing can be larger than 50 % as a function of changing fractal dimension and organic content. A comprehensive parameterization scheme for coated BC optical properties is developed with applications for modelling, ambient, and laboratory-based BC studies.
Helmi Uusitalo, Jenni Kontkanen, Ilona Ylivinkka, Ekaterina Ezhova, Anastasiia Demakova, Mikhail Arshinov, Boris Denisovich Belan, Denis Davydov, Nan Ma, Tuukka Petäjä, Alfred Wiedensohler, Markku Kulmala, and Tuomo Nieminen
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-530, https://doi.org/10.5194/acp-2021-530, 2021
Publication in ACP not foreseen
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Characteristics of formation of atmospheric aerosol at four boreal forest sites in Finland and Russian Siberia was analyzed. Our results provide information on the governing processes of atmospheric aerosol formation in the boreal forest area, which a substantial part of the continental biosphere. Aerosol formation was occurring less frequently at Siberian than in Finnish sites, which was affected by the lower particle growth rates and higher loss rates in Siberia.
Nahid Atashi, Dariush Rahimi, Victoria A. Sinclair, Martha A. Zaidan, Anton Rusanen, Henri Vuollekoski, Markku Kulmala, Timo Vesala, and Tareq Hussein
Hydrol. Earth Syst. Sci., 25, 4719–4740, https://doi.org/10.5194/hess-25-4719-2021, https://doi.org/10.5194/hess-25-4719-2021, 2021
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Dew formation potential during a long-term period (1979–2018) was assessed in Iran to identify dew formation zones and to investigate the impacts of long-term variation in meteorological parameters on dew formation. Six dew formation zones were identified based on cluster analysis of the time series of the simulated dew yield. The distribution of dew formation zones in Iran was closely aligned with topography and sources of moisture. The dew formation trend was significantly negative.
Janne Lampilahti, Hanna E. Manninen, Tuomo Nieminen, Sander Mirme, Mikael Ehn, Iida Pullinen, Katri Leino, Siegfried Schobesberger, Juha Kangasluoma, Jenni Kontkanen, Emma Järvinen, Riikka Väänänen, Taina Yli-Juuti, Radovan Krejci, Katrianne Lehtipalo, Janne Levula, Aadu Mirme, Stefano Decesari, Ralf Tillmann, Douglas R. Worsnop, Franz Rohrer, Astrid Kiendler-Scharr, Tuukka Petäjä, Veli-Matti Kerminen, Thomas F. Mentel, and Markku Kulmala
Atmos. Chem. Phys., 21, 12649–12663, https://doi.org/10.5194/acp-21-12649-2021, https://doi.org/10.5194/acp-21-12649-2021, 2021
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We studied aerosol particle formation and growth in different parts of the planetary boundary layer at two different locations (Po Valley, Italy, and Hyytiälä, Finland). The observations consist of airborne measurements on board an instrumented Zeppelin and a small airplane combined with comprehensive ground-based measurements.
Bjorn Stevens, Sandrine Bony, David Farrell, Felix Ament, Alan Blyth, Christopher Fairall, Johannes Karstensen, Patricia K. Quinn, Sabrina Speich, Claudia Acquistapace, Franziska Aemisegger, Anna Lea Albright, Hugo Bellenger, Eberhard Bodenschatz, Kathy-Ann Caesar, Rebecca Chewitt-Lucas, Gijs de Boer, Julien Delanoë, Leif Denby, Florian Ewald, Benjamin Fildier, Marvin Forde, Geet George, Silke Gross, Martin Hagen, Andrea Hausold, Karen J. Heywood, Lutz Hirsch, Marek Jacob, Friedhelm Jansen, Stefan Kinne, Daniel Klocke, Tobias Kölling, Heike Konow, Marie Lothon, Wiebke Mohr, Ann Kristin Naumann, Louise Nuijens, Léa Olivier, Robert Pincus, Mira Pöhlker, Gilles Reverdin, Gregory Roberts, Sabrina Schnitt, Hauke Schulz, A. Pier Siebesma, Claudia Christine Stephan, Peter Sullivan, Ludovic Touzé-Peiffer, Jessica Vial, Raphaela Vogel, Paquita Zuidema, Nicola Alexander, Lyndon Alves, Sophian Arixi, Hamish Asmath, Gholamhossein Bagheri, Katharina Baier, Adriana Bailey, Dariusz Baranowski, Alexandre Baron, Sébastien Barrau, Paul A. Barrett, Frédéric Batier, Andreas Behrendt, Arne Bendinger, Florent Beucher, Sebastien Bigorre, Edmund Blades, Peter Blossey, Olivier Bock, Steven Böing, Pierre Bosser, Denis Bourras, Pascale Bouruet-Aubertot, Keith Bower, Pierre Branellec, Hubert Branger, Michal Brennek, Alan Brewer, Pierre-Etienne Brilouet, Björn Brügmann, Stefan A. Buehler, Elmo Burke, Ralph Burton, Radiance Calmer, Jean-Christophe Canonici, Xavier Carton, Gregory Cato Jr., Jude Andre Charles, Patrick Chazette, Yanxu Chen, Michal T. Chilinski, Thomas Choularton, Patrick Chuang, Shamal Clarke, Hugh Coe, Céline Cornet, Pierre Coutris, Fleur Couvreux, Susanne Crewell, Timothy Cronin, Zhiqiang Cui, Yannis Cuypers, Alton Daley, Gillian M. Damerell, Thibaut Dauhut, Hartwig Deneke, Jean-Philippe Desbios, Steffen Dörner, Sebastian Donner, Vincent Douet, Kyla Drushka, Marina Dütsch, André Ehrlich, Kerry Emanuel, Alexandros Emmanouilidis, Jean-Claude Etienne, Sheryl Etienne-Leblanc, Ghislain Faure, Graham Feingold, Luca Ferrero, Andreas Fix, Cyrille Flamant, Piotr Jacek Flatau, Gregory R. Foltz, Linda Forster, Iulian Furtuna, Alan Gadian, Joseph Galewsky, Martin Gallagher, Peter Gallimore, Cassandra Gaston, Chelle Gentemann, Nicolas Geyskens, Andreas Giez, John Gollop, Isabelle Gouirand, Christophe Gourbeyre, Dörte de Graaf, Geiske E. de Groot, Robert Grosz, Johannes Güttler, Manuel Gutleben, Kashawn Hall, George Harris, Kevin C. Helfer, Dean Henze, Calvert Herbert, Bruna Holanda, Antonio Ibanez-Landeta, Janet Intrieri, Suneil Iyer, Fabrice Julien, Heike Kalesse, Jan Kazil, Alexander Kellman, Abiel T. Kidane, Ulrike Kirchner, Marcus Klingebiel, Mareike Körner, Leslie Ann Kremper, Jan Kretzschmar, Ovid Krüger, Wojciech Kumala, Armin Kurz, Pierre L'Hégaret, Matthieu Labaste, Tom Lachlan-Cope, Arlene Laing, Peter Landschützer, Theresa Lang, Diego Lange, Ingo Lange, Clément Laplace, Gauke Lavik, Rémi Laxenaire, Caroline Le Bihan, Mason Leandro, Nathalie Lefevre, Marius Lena, Donald Lenschow, Qiang Li, Gary Lloyd, Sebastian Los, Niccolò Losi, Oscar Lovell, Christopher Luneau, Przemyslaw Makuch, Szymon Malinowski, Gaston Manta, Eleni Marinou, Nicholas Marsden, Sebastien Masson, Nicolas Maury, Bernhard Mayer, Margarette Mayers-Als, Christophe Mazel, Wayne McGeary, James C. McWilliams, Mario Mech, Melina Mehlmann, Agostino Niyonkuru Meroni, Theresa Mieslinger, Andreas Minikin, Peter Minnett, Gregor Möller, Yanmichel Morfa Avalos, Caroline Muller, Ionela Musat, Anna Napoli, Almuth Neuberger, Christophe Noisel, David Noone, Freja Nordsiek, Jakub L. Nowak, Lothar Oswald, Douglas J. Parker, Carolyn Peck, Renaud Person, Miriam Philippi, Albert Plueddemann, Christopher Pöhlker, Veronika Pörtge, Ulrich Pöschl, Lawrence Pologne, Michał Posyniak, Marc Prange, Estefanía Quiñones Meléndez, Jule Radtke, Karim Ramage, Jens Reimann, Lionel Renault, Klaus Reus, Ashford Reyes, Joachim Ribbe, Maximilian Ringel, Markus Ritschel, Cesar B. Rocha, Nicolas Rochetin, Johannes Röttenbacher, Callum Rollo, Haley Royer, Pauline Sadoulet, Leo Saffin, Sanola Sandiford, Irina Sandu, Michael Schäfer, Vera Schemann, Imke Schirmacher, Oliver Schlenczek, Jerome Schmidt, Marcel Schröder, Alfons Schwarzenboeck, Andrea Sealy, Christoph J. Senff, Ilya Serikov, Samkeyat Shohan, Elizabeth Siddle, Alexander Smirnov, Florian Späth, Branden Spooner, M. Katharina Stolla, Wojciech Szkółka, Simon P. de Szoeke, Stéphane Tarot, Eleni Tetoni, Elizabeth Thompson, Jim Thomson, Lorenzo Tomassini, Julien Totems, Alma Anna Ubele, Leonie Villiger, Jan von Arx, Thomas Wagner, Andi Walther, Ben Webber, Manfred Wendisch, Shanice Whitehall, Anton Wiltshire, Allison A. Wing, Martin Wirth, Jonathan Wiskandt, Kevin Wolf, Ludwig Worbes, Ethan Wright, Volker Wulfmeyer, Shanea Young, Chidong Zhang, Dongxiao Zhang, Florian Ziemen, Tobias Zinner, and Martin Zöger
Earth Syst. Sci. Data, 13, 4067–4119, https://doi.org/10.5194/essd-13-4067-2021, https://doi.org/10.5194/essd-13-4067-2021, 2021
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The EUREC4A field campaign, designed to test hypothesized mechanisms by which clouds respond to warming and benchmark next-generation Earth-system models, is presented. EUREC4A comprised roughly 5 weeks of measurements in the downstream winter trades of the North Atlantic – eastward and southeastward of Barbados. It was the first campaign that attempted to characterize the full range of processes and scales influencing trade wind clouds.
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, https://doi.org/10.5194/gmd-14-5239-2021, https://doi.org/10.5194/gmd-14-5239-2021, 2021
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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.
Zhuohui Lin, Yonghong Wang, Feixue Zheng, Ying Zhou, Yishuo Guo, Zemin Feng, Chang Li, Yusheng Zhang, Simo Hakala, Tommy Chan, Chao Yan, Kaspar R. Daellenbach, Biwu Chu, Lubna Dada, Juha Kangasluoma, Lei Yao, Xiaolong Fan, Wei Du, Jing Cai, Runlong Cai, Tom V. Kokkonen, Putian Zhou, Lili Wang, Tuukka Petäjä, Federico Bianchi, Veli-Matti Kerminen, Yongchun Liu, and Markku Kulmala
Atmos. Chem. Phys., 21, 12173–12187, https://doi.org/10.5194/acp-21-12173-2021, https://doi.org/10.5194/acp-21-12173-2021, 2021
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We find that ammonium nitrate and aerosol water content contributed most during low mixing layer height conditions; this may further trigger enhanced formation of sulfate and organic aerosol via heterogeneous reactions. The results of this study contribute towards a more detailed understanding of the aerosol–chemistry–radiation–boundary layer feedback that is likely to be responsible for explosive aerosol mass growth events in urban Beijing.
Pak Lun Fung, Martha Arbayani Zaidan, Ola Surakhi, Sasu Tarkoma, Tuukka Petäjä, and Tareq Hussein
Atmos. Meas. Tech., 14, 5535–5554, https://doi.org/10.5194/amt-14-5535-2021, https://doi.org/10.5194/amt-14-5535-2021, 2021
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Aerosol size distribution measurements rely on a variety of techniques to classify the aerosol size and measure the size distribution. However, due to the instrumental insufficiency and inversion limitations, the raw dataset contains missing gaps or negative values, which hinder further analysis. With a merged particle size distribution in Jordan, this paper suggests a neural network method to estimate number concentrations at a particular size bin by the number concentration at other size bins.
Dimitrios Bousiotis, Francis D. Pope, David C. S. Beddows, Manuel Dall'Osto, Andreas Massling, Jakob Klenø Nøjgaard, Claus Nordstrøm, Jarkko V. Niemi, Harri Portin, Tuukka Petäjä, Noemi Perez, Andrés Alastuey, Xavier Querol, Giorgos Kouvarakis, Nikos Mihalopoulos, Stergios Vratolis, Konstantinos Eleftheriadis, Alfred Wiedensohler, Kay Weinhold, Maik Merkel, Thomas Tuch, and Roy M. Harrison
Atmos. Chem. Phys., 21, 11905–11925, https://doi.org/10.5194/acp-21-11905-2021, https://doi.org/10.5194/acp-21-11905-2021, 2021
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Formation of new particles is a key process in the atmosphere. New particle formation events arising from nucleation of gaseous precursors have been analysed in extensive datasets from 13 sites in five European countries in terms of frequency, nucleation rate, and particle growth rate, with several common features and many differences identified. Although nucleation frequencies are lower at roadside sites, nucleation rates and particle growth rates are typically higher.
Eija Asmi, John Backman, Henri Servomaa, Aki Virkkula, Maria I. Gini, Konstantinos Eleftheriadis, Thomas Müller, Sho Ohata, Yutaka Kondo, and Antti Hyvärinen
Atmos. Meas. Tech., 14, 5397–5413, https://doi.org/10.5194/amt-14-5397-2021, https://doi.org/10.5194/amt-14-5397-2021, 2021
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Absorbing aerosols are warming the planet and accurate measurements of their concentrations in pristine environments are needed. We applied eight different absorbing-aerosol measurement methods in a field campaign at the Arctic Pallas station. The filter-based techniques were found to be the most sensitive to detect the minuscule amounts of black carbon present, showing a 40 % agreement between them. Our results help to reduce uncertainties in absorbing aerosol measurements.
Mira L. Pöhlker, Minghui Zhang, Ramon Campos Braga, Ovid O. Krüger, Ulrich Pöschl, and Barbara Ervens
Atmos. Chem. Phys., 21, 11723–11740, https://doi.org/10.5194/acp-21-11723-2021, https://doi.org/10.5194/acp-21-11723-2021, 2021
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Clouds cool our atmosphere. The role of small aerosol particles in affecting them represents one of the largest uncertainties in current estimates of climate change. Traditionally it is assumed that cloud droplets only form particles of diameters ~ 100 nm (
accumulation mode). Previous studies suggest that this can also occur in smaller particles (
Aitken mode). Our study provides a general framework to estimate under which aerosol and cloud conditions Aitken mode particles affect clouds.
Markus Hartmann, Xianda Gong, Simonas Kecorius, Manuela van Pinxteren, Teresa Vogl, André Welti, Heike Wex, Sebastian Zeppenfeld, Hartmut Herrmann, Alfred Wiedensohler, and Frank Stratmann
Atmos. Chem. Phys., 21, 11613–11636, https://doi.org/10.5194/acp-21-11613-2021, https://doi.org/10.5194/acp-21-11613-2021, 2021
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Ice-nucleating particles (INPs) are not well characterized in the Arctic despite their importance for the Arctic energy budget. Little is known about their nature (mineral or biological) and sources (terrestrial or marine, long-range transport or local). We find indications that, at the beginning of the melt season, a local, biogenic, probably marine source is likely, but significant enrichment of INPs has to take place from the ocean to the aerosol phase.
Xiaolong Fan, Jing Cai, Chao Yan, Jian Zhao, Yishuo Guo, Chang Li, Kaspar R. Dällenbach, Feixue Zheng, Zhuohui Lin, Biwu Chu, Yonghong Wang, Lubna Dada, Qiaozhi Zha, Wei Du, Jenni Kontkanen, Theo Kurtén, Siddhart Iyer, Joni T. Kujansuu, Tuukka Petäjä, Douglas R. Worsnop, Veli-Matti Kerminen, Yongchun Liu, Federico Bianchi, Yee Jun Tham, Lei Yao, and Markku Kulmala
Atmos. Chem. Phys., 21, 11437–11452, https://doi.org/10.5194/acp-21-11437-2021, https://doi.org/10.5194/acp-21-11437-2021, 2021
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We observed significant concentrations of gaseous HBr and HCl throughout the winter and springtime in urban Beijing, China. Our results indicate that gaseous HCl and HBr are most likely originated from anthropogenic emissions such as burning activities, and the gas–aerosol partitioning may play a crucial role in contributing to the gaseous HCl and HBr. These observations suggest that there is an important recycling pathway of halogen species in inland megacities.
Congbo Song, Manuel Dall'Osto, Angelo Lupi, Mauro Mazzola, Rita Traversi, Silvia Becagli, Stefania Gilardoni, Stergios Vratolis, Karl Espen Yttri, David C. S. Beddows, Julia Schmale, James Brean, Agung Ghani Kramawijaya, Roy M. Harrison, and Zongbo Shi
Atmos. Chem. Phys., 21, 11317–11335, https://doi.org/10.5194/acp-21-11317-2021, https://doi.org/10.5194/acp-21-11317-2021, 2021
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We present a cluster analysis of relatively long-term (2015–2019) aerosol aerodynamic volume size distributions up to 20 μm in the Arctic for the first time. The study found that anthropogenic and natural aerosols comprised 27 % and 73 % of the occurrence of the coarse-mode aerosols, respectively. Our study shows that about two-thirds of the coarse-mode aerosols are related to two sea-spray-related aerosol clusters, indicating that sea spray aerosol may more complex in the Arctic environment.
Ana A. Piedehierro, André Welti, Angela Buchholz, Kimmo Korhonen, Iida Pullinen, Ilkka Summanen, Annele Virtanen, and Ari Laaksonen
Atmos. Chem. Phys., 21, 11069–11078, https://doi.org/10.5194/acp-21-11069-2021, https://doi.org/10.5194/acp-21-11069-2021, 2021
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Ice crystals in cirrus clouds contain particles that start ice formation. We study whether particles forming above boreal forests can help in the making of cirrus clouds and if the water content in the particles affects this property. In the laboratory, we made boreal-forest-like particles and cooled and humidified them to measure whether an ice crystal develops. We found that only when dry can these particles form an ice crystal but no better than solution droplets.
Haijie Tong, Fobang Liu, Alexander Filippi, Jake Wilson, Andrea M. Arangio, Yun Zhang, Siyao Yue, Steven Lelieveld, Fangxia Shen, Helmi-Marja K. Keskinen, Jing Li, Haoxuan Chen, Ting Zhang, Thorsten Hoffmann, Pingqing Fu, William H. Brune, Tuukka Petäjä, Markku Kulmala, Maosheng Yao, Thomas Berkemeier, Manabu Shiraiwa, and Ulrich Pöschl
Atmos. Chem. Phys., 21, 10439–10455, https://doi.org/10.5194/acp-21-10439-2021, https://doi.org/10.5194/acp-21-10439-2021, 2021
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We measured radical yields of aqueous PM2.5 extracts and found lower yields at higher concentrations of PM2.5. Abundances of water-soluble transition metals and aromatics in PM2.5 were positively correlated with the relative fraction of •OH but negatively correlated with the relative fraction of C-centered radicals among detected radicals. Composition-dependent reactive species yields may explain differences in the reactivity and health effects of PM2.5 in clean versus polluted air.
Liine Heikkinen, Mikko Äijälä, Kaspar R. Daellenbach, Gang Chen, Olga Garmash, Diego Aliaga, Frans Graeffe, Meri Räty, Krista Luoma, Pasi Aalto, Markku Kulmala, Tuukka Petäjä, Douglas Worsnop, and Mikael Ehn
Atmos. Chem. Phys., 21, 10081–10109, https://doi.org/10.5194/acp-21-10081-2021, https://doi.org/10.5194/acp-21-10081-2021, 2021
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In many locations worldwide aerosol particles have been shown to be made up of organic aerosol (OA). The boreal forest is a region where aerosol particles possess a high OA mass fraction. Here, we studied OA composition using the longest time series of OA composition ever obtained from a boreal environment. For this purpose, we tested a new analysis framework and discovered that most of the OA was highly oxidized, with strong seasonal behaviour reflecting different sources in summer and winter.
Magdalena Okuljar, Heino Kuuluvainen, Jenni Kontkanen, Olga Garmash, Miska Olin, Jarkko V. Niemi, Hilkka Timonen, Juha Kangasluoma, Yee Jun Tham, Rima Baalbaki, Mikko Sipilä, Laura Salo, Henna Lintusaari, Harri Portin, Kimmo Teinilä, Minna Aurela, Miikka Dal Maso, Topi Rönkkö, Tuukka Petäjä, and Pauli Paasonen
Atmos. Chem. Phys., 21, 9931–9953, https://doi.org/10.5194/acp-21-9931-2021, https://doi.org/10.5194/acp-21-9931-2021, 2021
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To estimate the relative contribution of different sources to the particle population in an urban environment, we conducted simultaneous measurements at a street canyon and an urban background station in Helsinki. We investigated the contribution of traffic and new particle formation to particles with a diameter between 1 and 800 nm. We found that during spring traffic does not dominate the particles smaller than 3 nm at either of the stations.
Rima Baalbaki, Michael Pikridas, Tuija Jokinen, Tiia Laurila, Lubna Dada, Spyros Bezantakos, Lauri Ahonen, Kimmo Neitola, Anne Maisser, Elie Bimenyimana, Aliki Christodoulou, Florin Unga, Chrysanthos Savvides, Katrianne Lehtipalo, Juha Kangasluoma, George Biskos, Tuukka Petäjä, Veli-Matti Kerminen, Jean Sciare, and Markku Kulmala
Atmos. Chem. Phys., 21, 9223–9251, https://doi.org/10.5194/acp-21-9223-2021, https://doi.org/10.5194/acp-21-9223-2021, 2021
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This study investigates new particle formation (NPF) in the less represented region of the Mediterranean basin using 1-year measurements of aerosol particles down to ~ 1 nm in diameter. We report a high frequency of NPF and give examples of interesting NPF features. We quantify the strength of NPF events by calculating formation rates and growth rates. We further unveil the atmospheric conditions and variables considered important for the intra-monthly and inter-monthly occurrence of NPF.
Wei Huang, Haiyan Li, Nina Sarnela, Liine Heikkinen, Yee Jun Tham, Jyri Mikkilä, Steven J. Thomas, Neil M. Donahue, Markku Kulmala, and Federico Bianchi
Atmos. Chem. Phys., 21, 8961–8977, https://doi.org/10.5194/acp-21-8961-2021, https://doi.org/10.5194/acp-21-8961-2021, 2021
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We show full characterization of gaseous organic compounds in a boreal forest. Molecular composition and volatility of gaseous organic compounds with different oxidation extents (from volatile organic compounds to highly oxygenated organic molecules) were investigated and discussed. We provide a more comprehensive understanding of atmospheric organic compounds in this boreal forest and new insights into interpreting ambient measurements or testing and improving parameterizations in models.
Djacinto Monteiro dos Santos, Luciana Varanda Rizzo, Samara Carbone, Patrick Schlag, and Paulo Artaxo
Atmos. Chem. Phys., 21, 8761–8773, https://doi.org/10.5194/acp-21-8761-2021, https://doi.org/10.5194/acp-21-8761-2021, 2021
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The metropolitan area of São Paulo (MASP), with very extensive biofuel use, has unique atmospheric chemistry among world megacities. In this study, we examine the complex relationships between aerosol chemical composition and particle size distribution. Our findings provide a better understanding of the dynamics of the physicochemical properties of submicron particles and highlight the key role of secondary organic aerosol formation in the pollution levels in São Paulo.
Jose Ruiz-Jimenez, Magdalena Okuljar, Outi-Maaria Sietiö, Giorgia Demaria, Thanaporn Liangsupree, Elisa Zagatti, Juho Aalto, Kari Hartonen, Jussi Heinonsalo, Jaana Bäck, Tuukka Petäjä, and Marja-Liisa Riekkola
Atmos. Chem. Phys., 21, 8775–8790, https://doi.org/10.5194/acp-21-8775-2021, https://doi.org/10.5194/acp-21-8775-2021, 2021
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Altogether, 84 size-segregated aerosol samples from four particle size fractions were collected at the Station for Measuring Forest Ecosystem-Atmosphere Relations, Hyytiälä, Finland, in autumn 2017 for the clarification of the complex interrelationships between airborne and particulate chemical traces, amino acids and saccharides, gene copy numbers (16S and 18S for bacteria and fungi, respectively), gas-phase chemistry, and the particle size distribution.
Wei Xu, Kirsten N. Fossum, Jurgita Ovadnevaite, Chunshui Lin, Ru-Jin Huang, Colin O'Dowd, and Darius Ceburnis
Atmos. Chem. Phys., 21, 8655–8675, https://doi.org/10.5194/acp-21-8655-2021, https://doi.org/10.5194/acp-21-8655-2021, 2021
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Cloud condensation nuclei (CCN) are an important topic in atmospheric studies, especially for evaluating the climate impact of aerosol. Here in this study, CCN closure is studied by using chemical composition based on an aerosol mass spectrometer (AMS) and hygroscopicity growth measurements based on a humidified tandem differential mobility analyzer (HTDMA) at the Mace Head atmospheric research station.
Mingyi Wang, Xu-Cheng He, Henning Finkenzeller, Siddharth Iyer, Dexian Chen, Jiali Shen, Mario Simon, Victoria Hofbauer, Jasper Kirkby, Joachim Curtius, Norbert Maier, Theo Kurtén, Douglas R. Worsnop, Markku Kulmala, Matti Rissanen, Rainer Volkamer, Yee Jun Tham, Neil M. Donahue, and Mikko Sipilä
Atmos. Meas. Tech., 14, 4187–4202, https://doi.org/10.5194/amt-14-4187-2021, https://doi.org/10.5194/amt-14-4187-2021, 2021
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Atmospheric iodine species are often short-lived with low abundance and have thus been challenging to measure. We show that the bromide chemical ionization mass spectrometry, compatible with both the atmospheric pressure and reduced pressure interfaces, can simultaneously detect various gas-phase iodine species. Combining calibration experiments and quantum chemical calculations, we quantify detection sensitivities to HOI, HIO3, I2, and H2SO4, giving detection limits down to < 106 molec. cm-3.
Dimitrios Bousiotis, Ajit Singh, Molly Haugen, David C. S. Beddows, Sebastián Diez, Killian L. Murphy, Pete M. Edwards, Adam Boies, Roy M. Harrison, and Francis D. Pope
Atmos. Meas. Tech., 14, 4139–4155, https://doi.org/10.5194/amt-14-4139-2021, https://doi.org/10.5194/amt-14-4139-2021, 2021
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Measurement and source apportionment of atmospheric pollutants are crucial for the assessment of air quality and the implementation of policies for their improvement. This study highlights the current capability of low-cost sensors in source identification and differentiation using clustering approaches. Future directions towards particulate matter source apportionment using low-cost OPCs are highlighted.
Markku Kulmala, Tom V. Kokkonen, Juha Pekkanen, Sami Paatero, Tuukka Petäjä, Veli-Matti Kerminen, and Aijun Ding
Atmos. Chem. Phys., 21, 8313–8322, https://doi.org/10.5194/acp-21-8313-2021, https://doi.org/10.5194/acp-21-8313-2021, 2021
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The eastern part of China as a whole is practically a gigacity with 650 million inhabitants. The gigacity, with its emissions, processes in the pollution cocktail and numerous feedbacks and interactions, has a crucial and big impact on regional air quality and on global climate. A large-scale research and innovation program is needed to meet the interlinked grand challenges in this gigacity and to serve as a platform for finding pathways for sustainable development of the globe.
Siqi Hou, Di Liu, Jingsha Xu, Tuan V. Vu, Xuefang Wu, Deepchandra Srivastava, Pingqing Fu, Linjie Li, Yele Sun, Athanasia Vlachou, Vaios Moschos, Gary Salazar, Sönke Szidat, André S. H. Prévôt, Roy M. Harrison, and Zongbo Shi
Atmos. Chem. Phys., 21, 8273–8292, https://doi.org/10.5194/acp-21-8273-2021, https://doi.org/10.5194/acp-21-8273-2021, 2021
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This study provides a newly developed method which combines radiocarbon (14C) with organic tracers to enable source apportionment of primary and secondary fossil vs. non-fossil sources of carbonaceous aerosols at an urban and a rural site of Beijing. The source apportionment results were compared with those by chemical mass balance and AMS/ACSM-PMF methods. Correlations of WINSOC and WSOC with different sources of OC were also performed to elucidate the formation mechanisms of SOC.
Janne Lampilahti, Katri Leino, Antti Manninen, Pyry Poutanen, Anna Franck, Maija Peltola, Paula Hietala, Lisa Beck, Lubna Dada, Lauriane Quéléver, Ronja Öhrnberg, Ying Zhou, Madeleine Ekblom, Ville Vakkari, Sergej Zilitinkevich, Veli-Matti Kerminen, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 21, 7901–7915, https://doi.org/10.5194/acp-21-7901-2021, https://doi.org/10.5194/acp-21-7901-2021, 2021
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Using airborne measurements we observed increased number concentrations of sub-25 nm particles in the upper residual layer. These particles may be entrained into the well-mixed boundary layer and observed at the surface. We attribute our observations to new particle formation in the topmost part of the residual layer.
Jingsha Xu, Di Liu, Xuefang Wu, Tuan V. Vu, Yanli Zhang, Pingqing Fu, Yele Sun, Weiqi Xu, Bo Zheng, Roy M. Harrison, and Zongbo Shi
Atmos. Chem. Phys., 21, 7321–7341, https://doi.org/10.5194/acp-21-7321-2021, https://doi.org/10.5194/acp-21-7321-2021, 2021
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Source apportionment of fine aerosols in an urban site of Beijing used a chemical mass balance (CMB) model. Seven primary sources (industrial/residential coal burning, biomass burning, gasoline/diesel vehicles, cooking and vegetative detritus) explained an average of 75.7 % and 56.1 % of fine OC in winter and summer, respectively. CMB was found to resolve more primary OA sources than AMS-PMF, but the latter apportioned more secondary OA sources.
Stephanie Bohlmann, Xiaoxia Shang, Ville Vakkari, Elina Giannakaki, Ari Leskinen, Kari E. J. Lehtinen, Sanna Pätsi, and Mika Komppula
Atmos. Chem. Phys., 21, 7083–7097, https://doi.org/10.5194/acp-21-7083-2021, https://doi.org/10.5194/acp-21-7083-2021, 2021
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Measurements of the multi-wavelength Raman polarization lidar PollyXT and a Halo Photonics StreamLine Doppler lidar have been combined with measurements of pollen type and concentration using a traditional pollen trap at the rural forest site in Vehmasmäki, Finland. Depolarization ratios were measured at three wavelengths. High depolarization ratios were detected during an event with high birch and spruce pollen concentrations and a wavelength dependence of the depolarization ratio was observed.
Eugene F. Mikhailov, Mira L. Pöhlker, Kathrin Reinmuth-Selzle, Sergey S. Vlasenko, Ovid O. Krüger, Janine Fröhlich-Nowoisky, Christopher Pöhlker, Olga A. Ivanova, Alexey A. Kiselev, Leslie A. Kremper, and Ulrich Pöschl
Atmos. Chem. Phys., 21, 6999–7022, https://doi.org/10.5194/acp-21-6999-2021, https://doi.org/10.5194/acp-21-6999-2021, 2021
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Subpollen particles are a relatively new subset of atmospheric aerosol particles. When pollen grains rupture, they release cytoplasmic fragments known as subpollen particles (SPPs). We found that SPPs, containing a broad spectrum of biopolymers and hydrocarbons, exhibit abnormally high water uptake. This effect may influence the life cycle of SPPs and the related direct and indirect impacts on radiation budget as well as reinforce their allergic potential.
Robbie Ramsay, Chiara F. Di Marco, Mathew R. Heal, Matthias Sörgel, Paulo Artaxo, Meinrat O. Andreae, and Eiko Nemitz
Biogeosciences, 18, 2809–2825, https://doi.org/10.5194/bg-18-2809-2021, https://doi.org/10.5194/bg-18-2809-2021, 2021
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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.
Candice L. Sirmollo, Don R. Collins, Jordan M. McCormick, Cassandra F. Milan, Matthew H. Erickson, James H. Flynn, Rebecca J. Sheesley, Sascha Usenko, Henry W. Wallace, Alexander A. T. Bui, Robert J. Griffin, Matthew Tezak, Sean M. Kinahan, and Joshua L. Santarpia
Atmos. Meas. Tech., 14, 3351–3370, https://doi.org/10.5194/amt-14-3351-2021, https://doi.org/10.5194/amt-14-3351-2021, 2021
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The newly developed portable 1 m3 CAGE chamber systems were characterized using data acquired during a 2-month field study in 2016 in a forested area north of Houston, TX, USA. Concentrations of several oxidant and organic compounds measured in the chamber were found to closely agree with those calculated with a zero-dimensional model. By tracking the modes of injected monodisperse particles, a pattern change was observed for hourly averaged growth rates between late summer and early fall.
Janaína P. Nascimento, Megan M. Bela, Bruno B. Meller, Alessandro L. Banducci, Luciana V. Rizzo, Angel Liduvino Vara-Vela, Henrique M. J. Barbosa, Helber Gomes, Sameh A. A. Rafee, Marco A. Franco, Samara Carbone, Glauber G. Cirino, Rodrigo A. F. Souza, Stuart A. McKeen, and Paulo Artaxo
Atmos. Chem. Phys., 21, 6755–6779, https://doi.org/10.5194/acp-21-6755-2021, https://doi.org/10.5194/acp-21-6755-2021, 2021
Andrea Cuesta-Mosquera, Griša Močnik, Luka Drinovec, Thomas Müller, Sascha Pfeifer, María Cruz Minguillón, Björn Briel, Paul Buckley, Vadimas Dudoitis, Javier Fernández-García, María Fernández-Amado, Joel Ferreira De Brito, Veronique Riffault, Harald Flentje, Eimear Heffernan, Nikolaos Kalivitis, Athina-Cerise Kalogridis, Hannes Keernik, Luminita Marmureanu, Krista Luoma, Angela Marinoni, Michael Pikridas, Gerhard Schauer, Norbert Serfozo, Henri Servomaa, Gloria Titos, Jesús Yus-Díez, Natalia Zioła, and Alfred Wiedensohler
Atmos. Meas. Tech., 14, 3195–3216, https://doi.org/10.5194/amt-14-3195-2021, https://doi.org/10.5194/amt-14-3195-2021, 2021
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Measurements of black carbon must be conducted with instruments operating in quality-checked and assured conditions to generate reliable and comparable data. Here, 23 Aethalometers monitoring black carbon mass concentrations in European networks were characterized and intercompared. The influence of different aerosol sources, maintenance activities, and the filter material on the instrumental variabilities were investigated. Good agreement and in general low deviations were seen.
Patricia K. Quinn, Elizabeth J. Thompson, Derek J. Coffman, Sunil Baidar, Ludovic Bariteau, Timothy S. Bates, Sebastien Bigorre, Alan Brewer, Gijs de Boer, Simon P. de Szoeke, Kyla Drushka, Gregory R. Foltz, Janet Intrieri, Suneil Iyer, Chris W. Fairall, Cassandra J. Gaston, Friedhelm Jansen, James E. Johnson, Ovid O. Krüger, Richard D. Marchbanks, Kenneth P. Moran, David Noone, Sergio Pezoa, Robert Pincus, Albert J. Plueddemann, Mira L. Pöhlker, Ulrich Pöschl, Estefania Quinones Melendez, Haley M. Royer, Malgorzata Szczodrak, Jim Thomson, Lucia M. Upchurch, Chidong Zhang, Dongxiao Zhang, and Paquita Zuidema
Earth Syst. Sci. Data, 13, 1759–1790, https://doi.org/10.5194/essd-13-1759-2021, https://doi.org/10.5194/essd-13-1759-2021, 2021
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ATOMIC took place in the northwestern tropical Atlantic during January and February of 2020 to gather information on shallow atmospheric convection, the effects of aerosols and clouds on the ocean surface energy budget, and mesoscale oceanic processes. Measurements made from the NOAA RV Ronald H. Brown and assets it deployed (instrumented mooring and uncrewed seagoing vehicles) are described herein to advance widespread use of the data by the ATOMIC and broader research communities.
Ville Vakkari, Holger Baars, Stephanie Bohlmann, Johannes Bühl, Mika Komppula, Rodanthi-Elisavet Mamouri, and Ewan James O'Connor
Atmos. Chem. Phys., 21, 5807–5820, https://doi.org/10.5194/acp-21-5807-2021, https://doi.org/10.5194/acp-21-5807-2021, 2021
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The depolarization ratio is a valuable parameter for aerosol categorization from remote sensing measurements. Here, we introduce particle depolarization ratio measurements at the 1565 nm wavelength, which is substantially longer than previously utilized wavelengths and enhances our capabilities to study the wavelength dependency of the particle depolarization ratio.
Ningjin Xu and Don R. Collins
Atmos. Meas. Tech., 14, 2891–2906, https://doi.org/10.5194/amt-14-2891-2021, https://doi.org/10.5194/amt-14-2891-2021, 2021
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Oxidation flow reactors (OFRs) are frequently used to study atmospheric chemistry and aerosol formation by accelerating by up to 10 000 times the reactions that can take hours, days, or even weeks in the atmosphere. Here we present the design and evaluation of a new all-Teflon OFR. The computational, laboratory, and field use data we present demonstrate that the PFA OFR is suitable for a range of applications, including the study of rapidly changing ambient concentrations.
Steven J. Campbell, Kate Wolfer, Battist Utinger, Joe Westwood, Zhi-Hui Zhang, Nicolas Bukowiecki, Sarah S. Steimer, Tuan V. Vu, Jingsha Xu, Nicholas Straw, Steven Thomson, Atallah Elzein, Yele Sun, Di Liu, Linjie Li, Pingqing Fu, Alastair C. Lewis, Roy M. Harrison, William J. Bloss, Miranda Loh, Mark R. Miller, Zongbo Shi, and Markus Kalberer
Atmos. Chem. Phys., 21, 5549–5573, https://doi.org/10.5194/acp-21-5549-2021, https://doi.org/10.5194/acp-21-5549-2021, 2021
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In this study, we quantify PM2.5 oxidative potential (OP), a metric widely suggested as a potential measure of particle toxicity, in Beijing in summer and winter using four acellular assays. We correlate PM2.5 OP with a comprehensive range of atmospheric and particle composition measurements, demonstrating inter-assay differences and seasonal variation of PM2.5 OP. Using multivariate statistical analysis, we highlight specific particle chemical components and sources that influence OP.
Yishuo Guo, Chao Yan, Chang Li, Wei Ma, Zemin Feng, Ying Zhou, Zhuohui Lin, Lubna Dada, Dominik Stolzenburg, Rujing Yin, Jenni Kontkanen, Kaspar R. Daellenbach, Juha Kangasluoma, Lei Yao, Biwu Chu, Yonghong Wang, Runlong Cai, Federico Bianchi, Yongchun Liu, and Markku Kulmala
Atmos. Chem. Phys., 21, 5499–5511, https://doi.org/10.5194/acp-21-5499-2021, https://doi.org/10.5194/acp-21-5499-2021, 2021
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Fog, cloud and haze are very common natural phenomena. Sulfuric acid (SA) is one of the key compounds forming those suspended particles, technically called aerosols, through gas-to-particle conversion. Therefore, the concentration level, source and sink of SA is very important. Our results show that ozonolysis of alkenes plays a major role in nighttime SA formation under unpolluted conditions in urban Beijing, and nighttime cluster mode particles are probably driven by SA in urban environments.
Pontus von Schoenberg, Peter Tunved, Håkan Grahn, Alfred Wiedensohler, Radovan Krejci, and Niklas Brännström
Atmos. Chem. Phys., 21, 5173–5193, https://doi.org/10.5194/acp-21-5173-2021, https://doi.org/10.5194/acp-21-5173-2021, 2021
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In a radiological emergency preparedness system, Lagrangian particle dispersion models are often used to track the dispersion of radioactive material. In this study we have shown the importance of simulating advanced aerosol dynamic processes that are commonly neglected or simplified in these simulations. We show that inclusion of detailed ambient-aerosol dynamics can play a large role in the model result in simulations adopting a more detailed representation of aerosol–cloud interactions.
Dana L. McGuffin, Yuanlong Huang, Richard C. Flagan, Tuukka Petäjä, B. Erik Ydstie, and Peter J. Adams
Geosci. Model Dev., 14, 1821–1839, https://doi.org/10.5194/gmd-14-1821-2021, https://doi.org/10.5194/gmd-14-1821-2021, 2021
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Atmospheric particle formation, emissions, and growth process rates are significant sources of uncertainty in predicting climate change. We aim to reduce that uncertainty by using measurements from several ground-based sites across Europe. We developed an estimation technique to adapt the governing process rates so model–measurement bias decays. The estimation framework developed has potential to improve model predictions while providing insight into the underlying atmospheric particle physics.
Johan Ström, Jonas Svensson, Henri Honkanen, Eija Asmi, Nathaniel B. Dkhar, Shresth Tayal, Ved P. Sharma, Rakesh Hooda, Outi Meinander, Matti Leppäranta, Hans-Werner Jacobi, Heikki Lihavainen, and Antti Hyvärinen
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-158, https://doi.org/10.5194/acp-2021-158, 2021
Revised manuscript not accepted
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Snow darkening in the Himalaya results from the deposition of different particles. Here we assess the change in the seasonal snow cover duration due to the presence of mineral dust and black carbon particles in the snow of Sunderdhunga valley, Central Himalaya, India. With the use of in situ weather station data, the snow melt-out date is estimated to be shifted ~13 days earlier due to the presence of the particles in the snow.
Thomas Thorp, Stephen R. Arnold, Richard J. Pope, Dominick V. Spracklen, Luke Conibear, Christoph Knote, Mikhail Arshinov, Boris Belan, Eija Asmi, Tuomas Laurila, Andrei I. Skorokhod, Tuomo Nieminen, and Tuukka Petäjä
Atmos. Chem. Phys., 21, 4677–4697, https://doi.org/10.5194/acp-21-4677-2021, https://doi.org/10.5194/acp-21-4677-2021, 2021
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We compare modelled near-surface pollutants with surface and satellite observations to better understand the controls on the regional concentrations of pollution in western Siberia for late spring and summer in 2011. We find two commonly used emission inventories underestimate human emissions when compared to observations. Transport emissions are the main source of pollutants within the region during this period, whilst fire emissions peak during June and are only significant south of 60° N.
Clémence Rose, Matti P. Rissanen, Siddharth Iyer, Jonathan Duplissy, Chao Yan, John B. Nowak, Aurélie Colomb, Régis Dupuy, Xu-Cheng He, Janne Lampilahti, Yee Jun Tham, Daniela Wimmer, Jean-Marc Metzger, Pierre Tulet, Jérôme Brioude, Céline Planche, Markku Kulmala, and Karine Sellegri
Atmos. Chem. Phys., 21, 4541–4560, https://doi.org/10.5194/acp-21-4541-2021, https://doi.org/10.5194/acp-21-4541-2021, 2021
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Sulfuric acid (H2SO4) is commonly accepted as a key precursor for atmospheric new particle formation. However, direct measurements of [H2SO4] remain challenging, motivating the development of proxies. Using data collected in two different volcanic plumes, we show, under these specific conditions, the good performance of a proxy from the literature and also highlight the benefit of the newly developed proxies for the prediction of the highest [H2SO4] values.
Haiyan Li, Manjula R. Canagaratna, Matthieu Riva, Pekka Rantala, Yanjun Zhang, Steven Thomas, Liine Heikkinen, Pierre-Marie Flaud, Eric Villenave, Emilie Perraudin, Douglas Worsnop, Markku Kulmala, Mikael Ehn, and Federico Bianchi
Atmos. Chem. Phys., 21, 4123–4147, https://doi.org/10.5194/acp-21-4123-2021, https://doi.org/10.5194/acp-21-4123-2021, 2021
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For the first time, we performed binPMF analysis on the complex mass spectra acquired with the Vocus PTR-TOF in two European pine forests and identified various primary emission sources and secondary oxidation processes of atmospheric organic vapors, i.e., terpenes and their oxidation products, with varying oxidation degrees. Further insights were gained regarding monoterpene and sesquiterpene reactions based on the interpretation results.
Julia Schneider, Kristina Höhler, Paavo Heikkilä, Jorma Keskinen, Barbara Bertozzi, Pia Bogert, Tobias Schorr, Nsikanabasi Silas Umo, Franziska Vogel, Zoé Brasseur, Yusheng Wu, Simo Hakala, Jonathan Duplissy, Dmitri Moisseev, Markku Kulmala, Michael P. Adams, Benjamin J. Murray, Kimmo Korhonen, Liqing Hao, Erik S. Thomson, Dimitri Castarède, Thomas Leisner, Tuukka Petäjä, and Ottmar Möhler
Atmos. Chem. Phys., 21, 3899–3918, https://doi.org/10.5194/acp-21-3899-2021, https://doi.org/10.5194/acp-21-3899-2021, 2021
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By triggering the formation of ice crystals, ice-nucleating particles (INP) strongly influence cloud formation. Continuous, long-term measurements are needed to characterize the atmospheric INP variability. Here, a first long-term time series of INP spectra measured in the boreal forest for more than 1 year is presented, showing a clear seasonal cycle. It is shown that the seasonal dependency of INP concentrations and prevalent INP types is driven by the abundance of biogenic aerosol.
Laurent Poulain, Benjamin Fahlbusch, Gerald Spindler, Konrad Müller, Dominik van Pinxteren, Zhijun Wu, Yoshiteru Iinuma, Wolfram Birmili, Alfred Wiedensohler, and Hartmut Herrmann
Atmos. Chem. Phys., 21, 3667–3684, https://doi.org/10.5194/acp-21-3667-2021, https://doi.org/10.5194/acp-21-3667-2021, 2021
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We present results from source apportionment analysis on the carbonaceous aerosol particles, including organic aerosol (OA) and equivalent black carbon (eBC), allowing us to distinguish local emissions from long-range transport for OA and eBC sources. By merging online chemical measurements and considering particle number size distribution, the different air masses reaching the sampling place were described and discussed, based on their respective chemical composition and size distribution.
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, https://doi.org/10.5194/acp-21-3685-2021, https://doi.org/10.5194/acp-21-3685-2021, 2021
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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
Dimitrios Bousiotis, James Brean, Francis D. Pope, Manuel Dall'Osto, Xavier Querol, Andrés Alastuey, Noemi Perez, Tuukka Petäjä, Andreas Massling, Jacob Klenø Nøjgaard, Claus Nordstrøm, Giorgos Kouvarakis, Stergios Vratolis, Konstantinos Eleftheriadis, Jarkko V. Niemi, Harri Portin, Alfred Wiedensohler, Kay Weinhold, Maik Merkel, Thomas Tuch, and Roy M. Harrison
Atmos. Chem. Phys., 21, 3345–3370, https://doi.org/10.5194/acp-21-3345-2021, https://doi.org/10.5194/acp-21-3345-2021, 2021
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New particle formation events from 16 sites over Europe have been studied, and the influence of meteorological and atmospheric composition variables has been investigated. Some variables, like solar radiation intensity and temperature, have a positive effect on the occurrence of these events, while others have a negative effect, affecting different aspects such as the rate at which particles are formed or grow. This effect varies depending on the site type and magnitude of these variables.
Sami D. Seppälä, Joel Kuula, Antti-Pekka Hyvärinen, Sanna Saarikoski, Topi Rönkkö, Jorma Keskinen, Jukka-Pekka Jalkanen, and Hilkka Timonen
Atmos. Chem. Phys., 21, 3215–3234, https://doi.org/10.5194/acp-21-3215-2021, https://doi.org/10.5194/acp-21-3215-2021, 2021
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The effects of fuel sulfur content restrictions implemented by the International Maritime Organization in the Baltic Sea (in July 2010 and January 2015) on the particle properties of ship exhaust plumes and ambient aerosol were studied. The restrictions reduced the particle number concentrations and median particle size in plumes and number concentrations in ambient aerosol. These changes may improve human health in coastal areas and decrease the cooling effect of exhaust emissions from ships.
Jonas Svensson, Johan Ström, Henri Honkanen, Eija Asmi, Nathaniel B. Dkhar, Shresth Tayal, Ved P. Sharma, Rakesh Hooda, Matti Leppäranta, Hans-Werner Jacobi, Heikki Lihavainen, and Antti Hyvärinen
Atmos. Chem. Phys., 21, 2931–2943, https://doi.org/10.5194/acp-21-2931-2021, https://doi.org/10.5194/acp-21-2931-2021, 2021
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Light-absorbing particles specifically affect snowmelt in the Himalayas. Through measurements of the constituents in glacier snow pits from the Indian Himalayas our investigations show that different snow layers display striking similarities. These similarities can be characterized by a deposition constant. Our results further indicate that mineral dust can be responsible for the majority of light absorption in the snow in this part of the Himalayas.
Imre Salma, Wanda Thén, Pasi Aalto, Veli-Matti Kerminen, Anikó Kern, Zoltán Barcza, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 21, 2861–2880, https://doi.org/10.5194/acp-21-2861-2021, https://doi.org/10.5194/acp-21-2861-2021, 2021
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The distribution of the monthly mean nucleation frequency possessed a characteristic pattern. Its shape was compared to those of environmental variables, including vegetation-derived properties. The spring maximum in the occurrence frequency often overlapped with the positive T anomaly. The link between the heat stress and the occurrence minimum in summer could not be proven, whereas an association between the occurrence frequency and vegetation growth dynamics was clearly identified in spring.
Nikolaos Evangeliou, Stephen M. Platt, Sabine Eckhardt, Cathrine Lund Myhre, Paolo Laj, Lucas Alados-Arboledas, John Backman, Benjamin T. Brem, Markus Fiebig, Harald Flentje, Angela Marinoni, Marco Pandolfi, Jesus Yus-Dìez, Natalia Prats, Jean P. Putaud, Karine Sellegri, Mar Sorribas, Konstantinos Eleftheriadis, Stergios Vratolis, Alfred Wiedensohler, and Andreas Stohl
Atmos. Chem. Phys., 21, 2675–2692, https://doi.org/10.5194/acp-21-2675-2021, https://doi.org/10.5194/acp-21-2675-2021, 2021
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Following the transmission of SARS-CoV-2 to Europe, social distancing rules were introduced to prevent further spread. We investigate the impacts of the European lockdowns on black carbon (BC) emissions by means of in situ observations and inverse modelling. BC emissions declined by 23 kt in Europe during the lockdowns as compared with previous years and by 11 % as compared to the period prior to lockdowns. Residential combustion prevailed in Eastern Europe, as confirmed by remote sensing data.
Runlong Cai, Chao Yan, Dongsen Yang, Rujing Yin, Yiqun Lu, Chenjuan Deng, Yueyun Fu, Jiaxin Ruan, Xiaoxiao Li, Jenni Kontkanen, Qiang Zhang, Juha Kangasluoma, Yan Ma, Jiming Hao, Douglas R. Worsnop, Federico Bianchi, Pauli Paasonen, Veli-Matti Kerminen, Yongchun Liu, Lin Wang, Jun Zheng, Markku Kulmala, and Jingkun Jiang
Atmos. Chem. Phys., 21, 2457–2468, https://doi.org/10.5194/acp-21-2457-2021, https://doi.org/10.5194/acp-21-2457-2021, 2021
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Based on long-term measurements, we discovered that the collision of H2SO4–amine clusters is the governing mechanism that initializes fast new particle formation in the polluted atmospheric environment of urban Beijing. The mechanism and the governing factors for H2SO4–amine nucleation in the polluted atmosphere are quantitatively investigated in this study.
Runlong Cai, Chenxi Li, Xu-Cheng He, Chenjuan Deng, Yiqun Lu, Rujing Yin, Chao Yan, Lin Wang, Jingkun Jiang, Markku Kulmala, and Juha Kangasluoma
Atmos. Chem. Phys., 21, 2287–2304, https://doi.org/10.5194/acp-21-2287-2021, https://doi.org/10.5194/acp-21-2287-2021, 2021
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Growth rate determines the survival probability of atmospheric new particles and hence their impacts. We clarify the impacts of coagulation on the values retrieved by the appearance time method, which is widely used for growth rate evaluation. A new formula with coagulation correction is proposed based on derivation and tested using both models and atmospheric data. We show that the sub-3 nm particle growth rate in polluted environments may be overestimated without the coagulation correction.
Myrto Gratsea, Tim Bösch, Panagiotis Kokkalis, Andreas Richter, Mihalis Vrekoussis, Stelios Kazadzis, Alexandra Tsekeri, Alexandros Papayannis, Maria Mylonaki, Vassilis Amiridis, Nikos Mihalopoulos, and Evangelos Gerasopoulos
Atmos. Meas. Tech., 14, 749–767, https://doi.org/10.5194/amt-14-749-2021, https://doi.org/10.5194/amt-14-749-2021, 2021
Krista Luoma, Jarkko V. Niemi, Minna Aurela, Pak Lun Fung, Aku Helin, Tareq Hussein, Leena Kangas, Anu Kousa, Topi Rönkkö, Hilkka Timonen, Aki Virkkula, and Tuukka Petäjä
Atmos. Chem. Phys., 21, 1173–1189, https://doi.org/10.5194/acp-21-1173-2021, https://doi.org/10.5194/acp-21-1173-2021, 2021
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This study combined black carbon measurements from 15 Finnish sites that represented different environments (traffic, detached housing area, urban background, and regional background). The seasonal and diurnal variations in the black carbon concentration were associated with local emissions from traffic and residential wood burning. The study observed decreasing trends in the black carbon concentration and associated them with decreases in traffic emissions.
Juha Sulo, Nina Sarnela, Jenni Kontkanen, Lauri Ahonen, Pauli Paasonen, Tiia Laurila, Tuija Jokinen, Juha Kangasluoma, Heikki Junninen, Mikko Sipilä, Tuukka Petäjä, Markku Kulmala, and Katrianne Lehtipalo
Atmos. Chem. Phys., 21, 695–715, https://doi.org/10.5194/acp-21-695-2021, https://doi.org/10.5194/acp-21-695-2021, 2021
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In this study, we analyzed over 5 years of sub-3 nm particle concentrations and their precursor vapors, identifying atmoshperic vapors important to the formation of these particles in the boreal forest. We also observed seasonal differences in both particle and precursor vapor concentrations and the formation pathways of these particles. Our results confirm the importance of organic vapors in atmospheric aerosol formation and highlight key seasonal differences that require further study.
David Brus, Jani Gustafsson, Ville Vakkari, Osku Kemppinen, Gijs de Boer, and Anne Hirsikko
Atmos. Chem. Phys., 21, 517–533, https://doi.org/10.5194/acp-21-517-2021, https://doi.org/10.5194/acp-21-517-2021, 2021
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This paper summarizes Finnish Meteorological Institute and Kansas State University unmanned aerial vehicle measurements during the summer 2018 Lower Atmospheric Process Studies at Elevation – a Remotely-piloted Aircraft Team Experiment (LAPSE-RATE) campaign in the San Luis Valley, providing an overview of the rotorcraft deployed, payloads, scientific goals and flight strategies and presenting observations of atmospheric thermodynamics and aerosol and gas parameters in the vertical column.
Oleg Sizov, Ekaterina Ezhova, Petr Tsymbarovich, Andrey Soromotin, Nikolay Prihod'ko, Tuukka Petäjä, Sergej Zilitinkevich, Markku Kulmala, Jaana Bäck, and Kajar Köster
Biogeosciences, 18, 207–228, https://doi.org/10.5194/bg-18-207-2021, https://doi.org/10.5194/bg-18-207-2021, 2021
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In changing climate, tundra is expected to turn into shrubs and trees, diminishing reindeer pasture and increasing risks of tick-borne diseases. However, this transition may require a disturbance. Fires in Siberia are increasingly widespread. We studied wildfire dynamics and tundra–forest transition over 60 years in northwest Siberia near the Arctic Circle. Based on satellite data analysis, we found that transition occurs in 40 %–85 % of burned tundra compared to 5 %–15 % in non-disturbed areas.
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, https://doi.org/10.5194/acp-21-339-2021, https://doi.org/10.5194/acp-21-339-2021, 2021
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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.
Marta Wenta, David Brus, Konstantinos Doulgeris, Ville Vakkari, and Agnieszka Herman
Earth Syst. Sci. Data, 13, 33–42, https://doi.org/10.5194/essd-13-33-2021, https://doi.org/10.5194/essd-13-33-2021, 2021
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Representations of the atmospheric boundary layer over sea ice are a challenge for numerical weather prediction models. To increase our understanding of the relevant processes, a field campaign was carried out over the sea ice in the Baltic Sea from 27 February to 2 March 2020. Observations included 27 unmanned aerial vehicle flights, four photogrammetry missions, and shore-based automatic weather station and lidar wind measurements. The dataset obtained is used to validate model results.
André Welti, Kimmo Korhonen, Pasi Miettinen, Ana A. Piedehierro, Yrjö Viisanen, Annele Virtanen, and Ari Laaksonen
Atmos. Meas. Tech., 13, 7059–7067, https://doi.org/10.5194/amt-13-7059-2020, https://doi.org/10.5194/amt-13-7059-2020, 2020
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We describe a modification of the SPectrometer for Ice Nuclei (SPIN) chamber to study ice nucleation at low temperatures, relevant for ice formation in cirrus clouds. Validation experiments of homogeneous freezing of aqueous ammonium sulfate droplets and heterogeneous ice nucleation on silver iodide particles are included to demonstrate the advantages of the modified SPIN chamber for the investigation of ice nucleation in the extended temperature range.
Jann Schrod, Erik S. Thomson, Daniel Weber, Jens Kossmann, Christopher Pöhlker, Jorge Saturno, Florian Ditas, Paulo Artaxo, Valérie Clouard, Jean-Marie Saurel, Martin Ebert, Joachim Curtius, and Heinz G. Bingemer
Atmos. Chem. Phys., 20, 15983–16006, https://doi.org/10.5194/acp-20-15983-2020, https://doi.org/10.5194/acp-20-15983-2020, 2020
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Long-term ice-nucleating particle (INP) data are presented from four semi-pristine sites located in the Amazon, the Caribbean, Germany and the Arctic. Average INP concentrations did not differ by orders of magnitude between the sites. For all sites short-term variability dominated the time series, which lacked clear trends and seasonalities. Common drivers to explain the INP levels and their variations could not be identified, illustrating the complex nature of heterogeneous ice nucleation.
Huan Song, Xiaorui Chen, Keding Lu, Qi Zou, Zhaofeng Tan, Hendrik Fuchs, Alfred Wiedensohler, Daniel R. Moon, Dwayne E. Heard, María-Teresa Baeza-Romero, Mei Zheng, Andreas Wahner, Astrid Kiendler-Scharr, and Yuanhang Zhang
Atmos. Chem. Phys., 20, 15835–15850, https://doi.org/10.5194/acp-20-15835-2020, https://doi.org/10.5194/acp-20-15835-2020, 2020
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Accurate calculation of the HO2 uptake coefficient is one of the key parameters to quantify the co-reduction of both aerosol and ozone pollution. We modelled various lab measurements of γHO2 based on a gas-liquid phase kinetic model and developed a state-of-the-art parameterized equation. Based on a dataset from a comprehensive field campaign in the North China Plain, we proposed that the determination of the heterogeneous uptake process for HO2 should be included in future field campaigns.
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, https://doi.org/10.5194/acp-20-15551-2020, https://doi.org/10.5194/acp-20-15551-2020, 2020
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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., https://doi.org/10.5194/amt-2020-447, https://doi.org/10.5194/amt-2020-447, 2020
Publication in AMT not foreseen
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Long-term (2005–2017) aerosol particulate matter (PM) concentration measurements at Finland at Station for Measuring Ecosystem-Atmosphere Relations (SMEAR II, Hyytiälä) have been measured with three different measurement equipment. The comparison revealed an equivalence among the three methods. Mass concentrations were generally highest in summer. The descending trend was visible here in spring, summer and winter. This might have resulted at least partly from air quality legislation.
Sho Ohata, Tatsuhiro Mori, Yutaka Kondo, Sangeeta Sharma, Antti Hyvärinen, Elisabeth Andrews, Peter Tunved, Eija Asmi, John Backman, Henri Servomaa, Daniel Veber, Makoto Koike, Yugo Kanaya, Atsushi Yoshida, Nobuhiro Moteki, Yongjing Zhao, Junji Matsushita, and Naga Oshima
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-1190, https://doi.org/10.5194/acp-2020-1190, 2020
Preprint withdrawn
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Reliable values of mass absorption cross sections (MAC) of black carbon (BC) are required to determine mass concentrations of BC at Arctic sites using different types of filter-based absorption photometers. We successfully estimated MAC values for these instruments through comparison with independent measurements of BC by continuous soot monitoring system called COSMOS. These MAC values are consistent with each other and applicable to study spatial and temporal variation of BC in the Arctic.
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Short summary
We trained machine learning models to estimate the number of aerosol particles large enough to form clouds and generated daily estimates for the entire globe. The models performed well in many continental regions but struggled in remote and marine areas. Still, this approach offers a way to quantify these particles in areas that lack direct measurements, helping us understand their influence on clouds and climate on a global scale.
We trained machine learning models to estimate the number of aerosol particles large enough to...
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