Articles | Volume 26, issue 16
https://doi.org/10.5194/acp-26-11991-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-26-11991-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
24 Aug 2026
Research article |
| 24 Aug 2026
| 24 Aug 2026
Importance of hydrated aerosol particles for aerosol–fog relationships in the Italian Po Valley
Almuth Neuberger
Department of Environmental Science, Stockholm University, Stockholm, Sweden
Bolin Centre for Climate Research, Stockholm, Sweden
Rahul Ranjan
Department of Environmental Science, Stockholm University, Stockholm, Sweden
Bolin Centre for Climate Research, Stockholm, Sweden
Hao Ding
Department of Meteorology, Stockholm University, Stockholm, Sweden
Bolin Centre for Climate Research, Stockholm, Sweden
Fredrik Mattsson
Department of Environmental Science, Stockholm University, Stockholm, Sweden
Bolin Centre for Climate Research, Stockholm, Sweden
Lea Haberstock
Department of Environmental Science, Stockholm University, Stockholm, Sweden
Bolin Centre for Climate Research, Stockholm, Sweden
Darrel Baumgardner
Droplet Measurement Technologies, LLC, Longmont, USA
Stefano Decesari
Institute of Atmospheric Science and Climate, National Research Council of Italy, Bologna, Italy
Annica M. L. Ekman
Department of Meteorology, Stockholm University, Stockholm, Sweden
Bolin Centre for Climate Research, Stockholm, Sweden
Dagen D. Hughes
Droplet Measurement Technologies, LLC, Longmont, USA
Claudia Mohr
Department of Environmental Science, Stockholm University, Stockholm, Sweden
Bolin Centre for Climate Research, Stockholm, Sweden
now at: Center for Energy and Environmental Sciences, Paul Scherrer Institute, Villigen, Switzerland
now at: Department of Environmental Systems Science, ETH Zurich, Zurich, Switzerland
Marco Paglione
Institute of Atmospheric Science and Climate, National Research Council of Italy, Bologna, Italy
Ilona Riipinen
Department of Environmental Science, Stockholm University, Stockholm, Sweden
Bolin Centre for Climate Research, Stockholm, Sweden
Matteo Rinaldi
Institute of Atmospheric Science and Climate, National Research Council of Italy, Bologna, Italy
Department of Environmental Science, Stockholm University, Stockholm, Sweden
Bolin Centre for Climate Research, Stockholm, Sweden
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Marco Paglione, Yufang Hao, Stefano Decesari, Mara Russo, Karam Mansour, Mauro Mazzola, Diego Fellin, Andrea Mazzanti, Emilio Tagliavini, Manousos Ioannis Manousakas, Evangelia Diapouli, Elena Barbaro, Matteo Feltracco, Kaspar R. Daellenbach, and Matteo Rinaldi
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Theresa Mathes, Heather Guy, John Prytherch, Julia Kojoj, Ian Brooks, Sonja Murto, Paul Zieger, Birgit Wehner, Michael Tjernström, and Andreas Held
Atmos. Chem. Phys., 25, 8455–8474, https://doi.org/10.5194/acp-25-8455-2025, https://doi.org/10.5194/acp-25-8455-2025, 2025
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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
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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.
Fredrik Mattsson, Almuth Neuberger, Liine Heikkinen, Yvette Gramlich, Marco Paglione, Matteo Rinaldi, Stefano Decesari, Paul Zieger, Ilona Riipinen, and Claudia Mohr
Atmos. Chem. Phys., 25, 7973–7989, https://doi.org/10.5194/acp-25-7973-2025, https://doi.org/10.5194/acp-25-7973-2025, 2025
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This study investigated aerosol–cloud interactions, focusing on organic nitrogen (ON) formation in the aqueous phase. Measurements were conducted in wintertime in the Po Valley, Italy, using aerosol mass spectrometry. The fog was enriched in more hygroscopic inorganic compounds and ON, containing, e.g., imidazoles. The formation of imidazole by aerosol–fog interactions could be confirmed for the first time in atmospheric observations. Findings highlight the role of fog in nitrogen aerosol formation.
Antonio Donateo, Daniela Famulari, Donato Giovannelli, Arturo Mariani, Mauro Mazzola, Stefano Decesari, and Gianluca Pappaccogli
Biogeosciences, 22, 2889–2908, https://doi.org/10.5194/bg-22-2889-2025, https://doi.org/10.5194/bg-22-2889-2025, 2025
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This study focuses on measurements of CO2 and CH4 turbulent fluxes in tundra ecosystems in the Svalbard islands over a 2-year period. Our results reveal dynamic interactions between climatic conditions and ecosystem activities such as photosynthesis and microbial activity. In summer, photosynthesis and microbial activity increase, leading to net carbon uptake and methane consumption. Wind influences soil drying and CH4 emissions. Thermal anomalies can reduce annual carbon uptake.
Anderson Da Silva, Louis Marelle, Jean-Christophe Raut, Yvette Gramlich, Karolina Siegel, Sophie L. Haslett, Claudia Mohr, and Jennie L. Thomas
Atmos. Chem. Phys., 25, 5331–5354, https://doi.org/10.5194/acp-25-5331-2025, https://doi.org/10.5194/acp-25-5331-2025, 2025
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Particle sources in polar climates are unclear, affecting climate representation in models. This study introduces an evaluated method for tracking particles with backward modeling. Tests on simulated particles allowed us to show that traditional detection methods often misidentify sources. An improved method that accurately traces the origins of aerosol particles in the Arctic is presented. The study recommends using this enhanced method for better source identification of atmospheric species.
Duncan Watson-Parris, Laura J. Wilcox, Camilla W. Stjern, Robert J. Allen, Geeta Persad, Massimo A. Bollasina, Annica M. L. Ekman, Carley E. Iles, Manoj Joshi, Marianne T. Lund, Daniel McCoy, Daniel M. Westervelt, Andrew I. L. Williams, and Bjørn H. Samset
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In 2020, regulations by the International Maritime Organization aimed to reduce aerosol emissions from ships. These aerosols previously had a cooling effect, which the regulations might reduce, revealing more greenhouse gas warming. Here we find that, while there is regional warming, the global 2020–2040 temperature rise is only +0.03 °C. This small change is difficult to distinguish from natural climate variability, indicating the regulations have had a limited effect on observed warming to date.
Roman Pohorsky, Andrea Baccarini, Natalie Brett, Brice Barret, Slimane Bekki, Gianluca Pappaccogli, Elsa Dieudonné, Brice Temime-Roussel, Barbara D'Anna, Meeta Cesler-Maloney, Antonio Donateo, Stefano Decesari, Kathy S. Law, William R. Simpson, Javier Fochesatto, Steve R. Arnold, and Julia Schmale
Atmos. Chem. Phys., 25, 3687–3715, https://doi.org/10.5194/acp-25-3687-2025, https://doi.org/10.5194/acp-25-3687-2025, 2025
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This study presents an analysis of vertical measurements of pollution in an Alaskan city during winter. It investigates the relationship between the atmospheric structure and the layering of aerosols and trace gases. Results indicate an overall very shallow surface mixing layer. The height of this layer is strongly influenced by a local shallow wind. The study also provides information on the pollution chemical composition at different altitudes, including pollution signatures from power plants.
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
Revised manuscript accepted 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.
Brice Barret, Patrice Medina, Natalie Brett, Roman Pohorsky, Kathy S. Law, Slimane Bekki, Gilberto J. Fochesatto, Julia Schmale, Steve R. Arnold, Andrea Baccarini, Maurizio Busetto, Meeta Cesler-Maloney, Barbara D'Anna, Stefano Decesari, Jingqiu Mao, Gianluca Pappaccogli, Joel Savarino, Federico Scoto, and William R. Simpson
Atmos. Meas. Tech., 18, 1163–1184, https://doi.org/10.5194/amt-18-1163-2025, https://doi.org/10.5194/amt-18-1163-2025, 2025
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The Fairbanks area experiences severe pollution episodes in winter because of enhanced emissions of pollutants trapped near the surface by strong temperature inversions. Low-cost sensors were deployed on board a car and a tethered balloon to measure the concentrations of gaseous pollutants (CO, O3, and NOx) in Fairbanks during winter 2022. Data calibration with reference measurements and machine learning methods enabled us to document pollution at the surface and power plant plumes aloft.
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.
Delaney B. Kilgour, Christopher M. Jernigan, Olga Garmash, Sneha Aggarwal, Shengqian Zhou, Claudia Mohr, Matt E. Salter, Joel A. Thornton, Jian Wang, Paul Zieger, and Timothy H. Bertram
Atmos. Chem. Phys., 25, 1931–1947, https://doi.org/10.5194/acp-25-1931-2025, https://doi.org/10.5194/acp-25-1931-2025, 2025
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We report simultaneous measurements of dimethyl sulfide (DMS) and hydroperoxymethyl thioformate (HPMTF) in the eastern North Atlantic. We use an observationally constrained box model to show that cloud loss is the dominant sink of HPMTF in this region over 6 weeks, resulting in large reductions in DMS-derived products that contribute to aerosol formation and growth. Our findings indicate that fast cloud processing of HPMTF must be included in global models to accurately capture the sulfur cycle.
Natalie Brett, Kathy S. Law, Steve R. Arnold, Javier G. Fochesatto, Jean-Christophe Raut, Tatsuo Onishi, Robert Gilliam, Kathleen Fahey, Deanna Huff, George Pouliot, Brice Barret, Elsa Dieudonné, Roman Pohorsky, Julia Schmale, Andrea Baccarini, Slimane Bekki, Gianluca Pappaccogli, Federico Scoto, Stefano Decesari, Antonio Donateo, Meeta Cesler-Maloney, William Simpson, Patrice Medina, Barbara D'Anna, Brice Temime-Roussel, Joel Savarino, Sarah Albertin, Jingqiu Mao, Becky Alexander, Allison Moon, Peter F. DeCarlo, Vanessa Selimovic, Robert Yokelson, and Ellis S. Robinson
Atmos. Chem. Phys., 25, 1063–1104, https://doi.org/10.5194/acp-25-1063-2025, https://doi.org/10.5194/acp-25-1063-2025, 2025
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Processes influencing dispersion of local anthropogenic pollution in Arctic wintertime are investigated with Lagrangian dispersion modelling. Simulated power plant plume rise that considers temperature inversion layers improves results compared to observations (interior Alaska). Modelled surface concentrations are improved by representation of vertical mixing and emission estimates. Large increases in diesel vehicle emissions at temperatures reaching −35°C are required to reproduce observed NOx.
Bighnaraj Sarangi, Darrel Baumgardner, Ana Isabel Calvo, Benjamin Bolaños-Rosero, Roberto Fraile, Alberto Rodríguez-Fernández, Delia Fernández-González, Carlos Blanco-Alegre, Cátia Gonçalves, Estela D. Vicente, and Olga L. Mayol-Bracero
Atmos. Chem. Phys., 25, 843–865, https://doi.org/10.5194/acp-25-843-2025, https://doi.org/10.5194/acp-25-843-2025, 2025
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Measurements of fluorescing aerosol particle properties have been made during two major African dust events, one over the island of Puerto Rico and the other over the city of León, Spain. The measurements were made with two wideband integrated bioaerosol spectrometers. A significant change in the background aerosol properties, at both locations, is observed when the dust is in the respective regions.
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.
Luís Filipe Escusa dos Santos, Hannah C. Frostenberg, Alejandro Baró Pérez, Annica M. L. Ekman, Luisa Ickes, and Erik S. Thomson
Atmos. Chem. Phys., 25, 119–142, https://doi.org/10.5194/acp-25-119-2025, https://doi.org/10.5194/acp-25-119-2025, 2025
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The Arctic is experiencing enhanced surface warming. The observed decline in Arctic sea-ice extent is projected to lead to an increase in Arctic shipping activity, which may lead to further climatic feedbacks. Using an atmospheric model and results from marine engine experiments that focused on fuel sulfur content reduction and exhaust wet scrubbing, we investigate how ship exhaust particles influence the properties of Arctic clouds. Implications for radiative surface processes are discussed.
Andreas Aktypis, Dontavious J. Sippial, Christina N. Vasilakopoulou, Angeliki Matrali, Christos Kaltsonoudis, Andrea Simonati, Marco Paglione, Matteo Rinaldi, Stefano Decesari, and Spyros N. Pandis
Atmos. Chem. Phys., 24, 13769–13791, https://doi.org/10.5194/acp-24-13769-2024, https://doi.org/10.5194/acp-24-13769-2024, 2024
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A dual-chamber system was deployed in two different environments (Po Valley, Italy, and Pertouli forest, Greece) to study the potential of ambient air directly injected into the chambers, to form secondary organic aerosol (SOA). In the Po Valley, the system reacts rapidly, forming large amounts of SOA, while in Pertouli the SOA formation chemistry appears to have been practically terminated before the beginning of most experiments, so there is little additional SOA formation potential left.
Julika Zinke, Gabriel Pereira Freitas, Rachel Ann Foster, Paul Zieger, Ernst Douglas Nilsson, Piotr Markuszewski, and Matthew Edward Salter
Atmos. Chem. Phys., 24, 13413–13428, https://doi.org/10.5194/acp-24-13413-2024, https://doi.org/10.5194/acp-24-13413-2024, 2024
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Bioaerosols, which can influence climate and human health, were studied in the Baltic Sea. In May and August 2021, we used a sea spray simulation chamber during two ship-based campaigns to collect and measure these aerosols. We found that microbes were enriched in air compared to seawater. Bacterial diversity was analysed using DNA sequencing. Our methods provided consistent estimates of microbial emission fluxes, aligning with previous studies.
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.
Abigail S. Williams, Jeramy L. Dedrick, Lynn M. Russell, Florian Tornow, Israel Silber, Ann M. Fridlind, Benjamin Swanson, Paul J. DeMott, Paul Zieger, and Radovan Krejci
Atmos. Chem. Phys., 24, 11791–11805, https://doi.org/10.5194/acp-24-11791-2024, https://doi.org/10.5194/acp-24-11791-2024, 2024
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The measured aerosol size distribution modes reveal distinct properties characteristic of cold-air outbreaks in the Norwegian Arctic. We find higher sea spray number concentrations, smaller Hoppel minima, lower effective supersaturations, and accumulation-mode particle scavenging during cold-air outbreaks. These results advance our understanding of cold-air outbreak aerosol–cloud interactions in order to improve their accurate representation in models.
Xiaoli Shen, David M. Bell, Hugh Coe, Naruki Hiranuma, Fabian Mahrt, Nicholas A. Marsden, Claudia Mohr, Daniel M. Murphy, Harald Saathoff, Johannes Schneider, Jacqueline Wilson, Maria A. Zawadowicz, Alla Zelenyuk, Paul J. DeMott, Ottmar Möhler, and Daniel J. Cziczo
Atmos. Chem. Phys., 24, 10869–10891, https://doi.org/10.5194/acp-24-10869-2024, https://doi.org/10.5194/acp-24-10869-2024, 2024
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Single-particle mass spectrometry (SPMS) is commonly used to measure the chemical composition and mixing state of aerosol particles. Intercomparison of SPMS instruments was conducted. All instruments reported similar size ranges and common spectral features. The instrument-specific detection efficiency was found to be more dependent on particle size than type. All differentiated secondary organic aerosol, soot, and soil dust but had difficulties differentiating among minerals and dusts.
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.
Gabriel Pereira Freitas, Ben Kopec, Kouji Adachi, Radovan Krejci, Dominic Heslin-Rees, Karl Espen Yttri, Alun Hubbard, Jeffrey M. Welker, and Paul Zieger
Atmos. Chem. Phys., 24, 5479–5494, https://doi.org/10.5194/acp-24-5479-2024, https://doi.org/10.5194/acp-24-5479-2024, 2024
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Bioaerosols can participate in ice formation within clouds. In the Arctic, where global warming manifests most, they may become more important as their sources prevail for longer periods of the year. We have directly measured bioaerosols within clouds for a full year at an Arctic mountain site using a novel combination of cloud particle sampling and single-particle techniques. We show that bioaerosols act as cloud seeds and may influence the presence of ice within clouds.
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.
Mahen Konwar, Benjamin Werden, Edward C. Fortner, Sudarsan Bera, Mercy Varghese, Subharthi Chowdhuri, Kurt Hibert, Philip Croteau, John Jayne, Manjula Canagaratna, Neelam Malap, Sandeep Jayakumar, Shivsai A. Dixit, Palani Murugavel, Duncan Axisa, Darrel Baumgardner, Peter F. DeCarlo, Doug R. Worsnop, and Thara Prabhakaran
Atmos. Meas. Tech., 17, 2387–2400, https://doi.org/10.5194/amt-17-2387-2024, https://doi.org/10.5194/amt-17-2387-2024, 2024
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In a warm cloud seeding experiment hygroscopic particles are released to alter cloud processes to induce early raindrops. During the Cloud–Aerosol Interaction and Precipitation Enhancement Experiment, airborne mini aerosol mass spectrometers analyse the particles on which clouds form. The seeded clouds showed higher concentrations of chlorine and potassium, the oxidizing agents of flares. Small cloud droplet concentrations increased, and seeding particles were detected in deep cloud depths.
Alejandro Baró Pérez, Michael S. Diamond, Frida A.-M. Bender, Abhay Devasthale, Matthias Schwarz, Julien Savre, Juha Tonttila, Harri Kokkola, Hyunho Lee, David Painemal, and Annica M. L. Ekman
Atmos. Chem. Phys., 24, 4591–4610, https://doi.org/10.5194/acp-24-4591-2024, https://doi.org/10.5194/acp-24-4591-2024, 2024
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We use a numerical model to study interactions between humid light-absorbing aerosol plumes, clouds, and radiation over the southeast Atlantic. We find that the warming produced by the aerosols reduces cloud cover, especially in highly polluted situations. Aerosol impacts on drizzle play a minor role. However, aerosol effects on cloud reflectivity and moisture-induced changes in cloud cover dominate the climatic response and lead to an overall cooling by the biomass burning plumes.
Wei Huang, Cheng Wu, Linyu Gao, Yvette Gramlich, Sophie L. Haslett, Joel Thornton, Felipe D. Lopez-Hilfiker, Ben H. Lee, Junwei Song, Harald Saathoff, Xiaoli Shen, Ramakrishna Ramisetty, Sachchida N. Tripathi, Dilip Ganguly, Feng Jiang, Magdalena Vallon, Siegfried Schobesberger, Taina Yli-Juuti, and Claudia Mohr
Atmos. Chem. Phys., 24, 2607–2624, https://doi.org/10.5194/acp-24-2607-2024, https://doi.org/10.5194/acp-24-2607-2024, 2024
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We present distinct molecular composition and volatility of oxygenated organic aerosol particles in different rural, urban, and mountain environments. We do a comprehensive investigation of the relationship between the chemical composition and volatility of oxygenated organic aerosol particles across different systems and environments. This study provides implications for volatility descriptions of oxygenated organic aerosol particles in different model frameworks.
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.
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.
Julika Zinke, Ernst Douglas Nilsson, Piotr Markuszewski, Paul Zieger, Eva Monica Mårtensson, Anna Rutgersson, Erik Nilsson, and Matthew Edward Salter
Atmos. Chem. Phys., 24, 1895–1918, https://doi.org/10.5194/acp-24-1895-2024, https://doi.org/10.5194/acp-24-1895-2024, 2024
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We conducted two research campaigns in the Baltic Sea, during which we combined laboratory sea spray simulation experiments with flux measurements on a nearby island. To combine these two methods, we scaled the laboratory measurements to the flux measurements using three different approaches. As a result, we derived a parameterization that is dependent on wind speed and wave state for particles with diameters 0.015–10 μm. This parameterization is applicable to low-salinity waters.
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.
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.
Ghislain Motos, Gabriel Freitas, Paraskevi Georgakaki, Jörg Wieder, Guangyu Li, Wenche Aas, Chris Lunder, Radovan Krejci, Julie Thérèse Pasquier, Jan Henneberger, Robert Oscar David, Christoph Ritter, Claudia Mohr, Paul Zieger, and Athanasios Nenes
Atmos. Chem. Phys., 23, 13941–13956, https://doi.org/10.5194/acp-23-13941-2023, https://doi.org/10.5194/acp-23-13941-2023, 2023
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Low-altitude clouds play a key role in regulating the climate of the Arctic, a region that suffers from climate change more than any other on the planet. We gathered meteorological and aerosol physical and chemical data over a year and utilized them for a parameterization that help us unravel the factors driving and limiting the efficiency of cloud droplet formation. We then linked this information to the sources of aerosol found during each season and to processes of cloud glaciation.
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.
Karolina Siegel, Yvette Gramlich, Sophie L. Haslett, Gabriel Freitas, Radovan Krejci, Paul Zieger, and Claudia Mohr
Atmos. Chem. Phys., 23, 7569–7587, https://doi.org/10.5194/acp-23-7569-2023, https://doi.org/10.5194/acp-23-7569-2023, 2023
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Hydroperoxymethyl thioformate (HPMTF) is a recently discovered oxidation product of dimethyl sulfide (DMS). We present a full year of concurrent gas- and particle-phase observations of HPMTF and other DMS oxidation products from the Arctic. We did not observe significant amounts of HPMTF in the particle phase but a good agreement between gas-phase HMPTF and methanesulfonic acid in the summer. Our study provides information about the relationship between HPMTF and other DMS oxidation products.
Amir Yazdani, Satoshi Takahama, John K. Kodros, Marco Paglione, Mauro Masiol, Stefania Squizzato, Kalliopi Florou, Christos Kaltsonoudis, Spiro D. Jorga, Spyros N. Pandis, and Athanasios Nenes
Atmos. Chem. Phys., 23, 7461–7477, https://doi.org/10.5194/acp-23-7461-2023, https://doi.org/10.5194/acp-23-7461-2023, 2023
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Organic aerosols directly emitted from wood and pellet stove combustion are found to chemically transform (approximately 15 %–35 % by mass) under daytime aging conditions simulated in an environmental chamber. A new marker for lignin-like compounds is found to degrade at a different rate than previously identified biomass burning markers and can potentially provide indication of aging time in ambient samples.
Antonio Donateo, Gianluca Pappaccogli, Daniela Famulari, Mauro Mazzola, Federico Scoto, and Stefano Decesari
Atmos. Chem. Phys., 23, 7425–7445, https://doi.org/10.5194/acp-23-7425-2023, https://doi.org/10.5194/acp-23-7425-2023, 2023
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This work aims to measure the turbulent fluxes and the dry deposition velocity for size-segregated particles (from ultrafine to quasi-coarse range) at an Arctic site (Svalbard). Aiming to characterize the effect of surface properties on dry deposition, continuous observations were performed from the coldest months (on snow surface) to the snow melting period and throughout the summer (snow-free surface). A data fit of the deposition velocity as a function of particle diameters will be provided.
Emelie L. Graham, Cheng Wu, David M. Bell, Amelie Bertrand, Sophie L. Haslett, Urs Baltensperger, Imad El Haddad, Radovan Krejci, Ilona Riipinen, and Claudia Mohr
Atmos. Chem. Phys., 23, 7347–7362, https://doi.org/10.5194/acp-23-7347-2023, https://doi.org/10.5194/acp-23-7347-2023, 2023
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The volatility of an aerosol particle is an important parameter for describing its atmospheric lifetime. We studied the volatility of secondary organic aerosols from nitrate-initiated oxidation of three biogenic precursors with experimental methods and model simulations. We saw higher volatility than for the corresponding ozone system, and our simulations produced variable results with different parameterizations which warrant a re-evaluation of the treatment of the nitrate functional group.
Ines Bulatovic, Julien Savre, Michael Tjernström, Caroline Leck, and Annica M. L. Ekman
Atmos. Chem. Phys., 23, 7033–7055, https://doi.org/10.5194/acp-23-7033-2023, https://doi.org/10.5194/acp-23-7033-2023, 2023
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We use numerical modeling with detailed cloud microphysics to investigate a low-altitude cloud system consisting of two cloud layers – a type of cloud situation which was commonly observed during the summer of 2018 in the central Arctic (north of 80° N). The model generally reproduces the observed cloud layers and the thermodynamic structure of the lower atmosphere well. The cloud system is maintained unless there are low aerosol number concentrations or high large-scale wind speeds.
Yvette Gramlich, Karolina Siegel, Sophie L. Haslett, Gabriel Freitas, Radovan Krejci, Paul Zieger, and Claudia Mohr
Atmos. Chem. Phys., 23, 6813–6834, https://doi.org/10.5194/acp-23-6813-2023, https://doi.org/10.5194/acp-23-6813-2023, 2023
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In this study, we investigate the chemical composition of aerosol particles forming clouds in the Arctic. During year-long observations at a mountain site on Svalbard, we find a large contribution of naturally derived aerosol particles in the fraction forming clouds in the summer. Our observations indicate that most aerosol particles can serve as cloud seeds in this remote environment.
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.
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.
Ruth Price, Andrea Baccarini, Julia Schmale, Paul Zieger, Ian M. Brooks, Paul Field, and Ken S. Carslaw
Atmos. Chem. Phys., 23, 2927–2961, https://doi.org/10.5194/acp-23-2927-2023, https://doi.org/10.5194/acp-23-2927-2023, 2023
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Arctic clouds can control how much energy is absorbed by the surface or reflected back to space. Using a computer model of the atmosphere we investigated the formation of atmospheric particles that allow cloud droplets to form. We found that particles formed aloft are transported to the lowest part of the Arctic atmosphere and that this is a key source of particles. Our results have implications for the way Arctic clouds will behave in the future as climate change continues to impact the region.
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.
Kouji Adachi, Yutaka Tobo, Makoto Koike, Gabriel Freitas, Paul Zieger, and Radovan Krejci
Atmos. Chem. Phys., 22, 14421–14439, https://doi.org/10.5194/acp-22-14421-2022, https://doi.org/10.5194/acp-22-14421-2022, 2022
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Ambient aerosol and cloud residual particles in the fine mode were collected at Zeppelin Observatory in Svalbard and were analyzed using transmission electron microscopy. Fractions of mineral dust and sea salt particles increased in cloud residual samples collected at ambient temperatures below 0 °C. This study highlights the variety of aerosol and cloud residual particle compositions and mixing states that influence or are influenced by aerosol–cloud interactions in Arctic low-level clouds.
David M. Bell, Cheng Wu, Amelie Bertrand, Emelie Graham, Janne Schoonbaert, Stamatios Giannoukos, Urs Baltensperger, Andre S. H. Prevot, Ilona Riipinen, Imad El Haddad, and Claudia Mohr
Atmos. Chem. Phys., 22, 13167–13182, https://doi.org/10.5194/acp-22-13167-2022, https://doi.org/10.5194/acp-22-13167-2022, 2022
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A series of studies designed to investigate the evolution of organic aerosol were performed in an atmospheric simulation chamber, using a common oxidant found at night (NO3). The chemical composition steadily changed from its initial composition via different chemical reactions that were taking place inside of the aerosol particle. These results show that the composition of organic aerosol steadily changes during its lifetime in the atmosphere.
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.
Bighnaraj Sarangi, Darrel Baumgardner, Benjamin Bolaños-Rosero, and Olga L. Mayol-Bracero
Atmos. Chem. Phys., 22, 9647–9661, https://doi.org/10.5194/acp-22-9647-2022, https://doi.org/10.5194/acp-22-9647-2022, 2022
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Here, the fluorescent characteristics and cloud-forming efficiency of aerosols at an urban site in Puerto Rico are discussed. The results from this pilot study highlight the capabilities of ultraviolet-induced fluorescence (UV-IF) measurements for characterizing the properties of fluorescing aerosol particles, as they relate to the daily evolution of primary biological aerosol particles. This work has established a database of measurements on which future, longer-term studies will be initiated.
Varun Kumar, Stamatios Giannoukos, Sophie L. Haslett, Yandong Tong, Atinderpal Singh, Amelie Bertrand, Chuan Ping Lee, Dongyu S. Wang, Deepika Bhattu, Giulia Stefenelli, Jay S. Dave, Joseph V. Puthussery, Lu Qi, Pawan Vats, Pragati Rai, Roberto Casotto, Rangu Satish, Suneeti Mishra, Veronika Pospisilova, Claudia Mohr, David M. Bell, Dilip Ganguly, Vishal Verma, Neeraj Rastogi, Urs Baltensperger, Sachchida N. Tripathi, André S. H. Prévôt, and Jay G. Slowik
Atmos. Chem. Phys., 22, 7739–7761, https://doi.org/10.5194/acp-22-7739-2022, https://doi.org/10.5194/acp-22-7739-2022, 2022
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Here we present source apportionment results from the first field deployment in Delhi of an extractive electrospray ionization time-of-flight mass spectrometer (EESI-TOF). The EESI-TOF is a recently developed instrument capable of providing uniquely detailed online chemical characterization of organic aerosol (OA), in particular the secondary OA (SOA) fraction. Here, we are able to apportion not only primary OA but also SOA to specific sources, which is performed for the first time in Delhi.
Linyu Gao, Junwei Song, Claudia Mohr, Wei Huang, Magdalena Vallon, Feng Jiang, Thomas Leisner, and Harald Saathoff
Atmos. Chem. Phys., 22, 6001–6020, https://doi.org/10.5194/acp-22-6001-2022, https://doi.org/10.5194/acp-22-6001-2022, 2022
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We study secondary organic aerosol (SOA) from β-caryophyllene (BCP) ozonolysis with and without nitrogen oxides over 213–313 K in the simulation chamber. The yields and the rate constants were determined at 243–313 K. Chemical compositions varied at different temperatures, indicating a strong impact on the BCP ozonolysis pathways. This work helps to better understand the SOA from BCP ozonolysis for conditions representative of the real atmosphere from the boundary layer to the upper troposphere.
Haiyan Li, Thomas Golin Almeida, Yuanyuan Luo, Jian Zhao, Brett B. Palm, Christopher D. Daub, Wei Huang, Claudia Mohr, Jordan E. Krechmer, Theo Kurtén, and Mikael Ehn
Atmos. Meas. Tech., 15, 1811–1827, https://doi.org/10.5194/amt-15-1811-2022, https://doi.org/10.5194/amt-15-1811-2022, 2022
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This work evaluated the potential for PTR-based mass spectrometers to detect ROOR and ROOH peroxides both experimentally and through computations. Laboratory experiments using a Vocus PTR observed only noisy signals of potential dimers during α-pinene ozonolysis and a few small signals of dimeric compounds during cyclohexene ozonolysis. Quantum chemical calculations for model ROOR and ROOH systems showed that most of these peroxides should fragment partially following protonation.
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.
Julia Schmale, Sangeeta Sharma, Stefano Decesari, Jakob Pernov, Andreas Massling, Hans-Christen Hansson, Knut von Salzen, Henrik Skov, Elisabeth Andrews, Patricia K. Quinn, Lucia M. Upchurch, Konstantinos Eleftheriadis, Rita Traversi, Stefania Gilardoni, Mauro Mazzola, James Laing, and Philip Hopke
Atmos. Chem. Phys., 22, 3067–3096, https://doi.org/10.5194/acp-22-3067-2022, https://doi.org/10.5194/acp-22-3067-2022, 2022
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Long-term data sets of Arctic aerosol properties from 10 stations across the Arctic provide evidence that anthropogenic influence on the Arctic atmospheric chemical composition has declined in winter, a season which is typically dominated by mid-latitude emissions. The number of significant trends in summer is smaller than in winter, and overall the pattern is ambiguous with some significant positive and negative trends. This reflects the mixed influence of natural and anthropogenic emissions.
Graciela B. Raga, Darrel Baumgardner, Blanca Rios, Yanet Díaz-Esteban, Alejandro Jaramillo, Martin Gallagher, Bastien Sauvage, Pawel Wolff, and Gary Lloyd
Atmos. Chem. Phys., 22, 2269–2292, https://doi.org/10.5194/acp-22-2269-2022, https://doi.org/10.5194/acp-22-2269-2022, 2022
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The In-Service Aircraft for a Global Observing System (IAGOS) is a small fleet of commercial aircraft that carry a suite of meteorological, gas, aerosol, and cloud sensors and have been measuring worldwide for almost 9 years, since late 2011. Extreme ice events (EIEs) have been identified from the IAGOS cloud measurements and linked to surface emissions for biomass and fossil fuel consumption. The results reported here are highly relevant for climate change and flight operations forecasting.
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.
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.
Miska Olin, David Patoulias, Heino Kuuluvainen, Jarkko V. Niemi, Topi Rönkkö, Spyros N. Pandis, Ilona Riipinen, and Miikka Dal Maso
Atmos. Chem. Phys., 22, 1131–1148, https://doi.org/10.5194/acp-22-1131-2022, https://doi.org/10.5194/acp-22-1131-2022, 2022
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An emission factor particle size distribution was determined from the measurements at an urban traffic site. It was used in updating a pre-existing emission inventory, and regional modeling was performed after the update. Emission inventories typically underestimate nanoparticle emissions due to challenges in determining them with high certainty. This update reveals that the simulated aerosol levels have previously been underestimated especially for urban areas and for sub-50 nm particles.
Elvis Torres-Delgado, Darrel Baumgardner, and Olga L. Mayol-Bracero
Atmos. Chem. Phys., 21, 18011–18027, https://doi.org/10.5194/acp-21-18011-2021, https://doi.org/10.5194/acp-21-18011-2021, 2021
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African dust aerosols can travel thousands of kilometers and reach the Caribbean and other places, where they can serve as ice and cloud condensation nuclei and alter precipitation patterns. Cloud microphysical properties (droplet number and size) were measured in a Caribbean tropical montane cloud forest along with models and satellite products. The results of the study suggest that meteorology and air mass history are more important for cloud processes than aerosols transported from Africa.
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.
Cheng Wu, David M. Bell, Emelie L. Graham, Sophie Haslett, Ilona Riipinen, Urs Baltensperger, Amelie Bertrand, Stamatios Giannoukos, Janne Schoonbaert, Imad El Haddad, Andre S. H. Prevot, Wei Huang, and Claudia Mohr
Atmos. Chem. Phys., 21, 14907–14925, https://doi.org/10.5194/acp-21-14907-2021, https://doi.org/10.5194/acp-21-14907-2021, 2021
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Night-time reactions of biogenic volatile organic compounds and nitrate radicals can lead to the formation of secondary organic aerosol (BSOANO3). Here, we study the impacts of light exposure on the BSOANO3 from three biogenic precursors. Our results suggest that photolysis causes photodegradation of a substantial fraction of BSOANO3, changes the chemical composition and bulk volatility, and might be a potentially important loss pathway of BSOANO3 during the night-to-day transition.
Matteo Rinaldi, Naruki Hiranuma, Gianni Santachiara, Mauro Mazzola, Karam Mansour, Marco Paglione, Cheyanne A. Rodriguez, Rita Traversi, Silvia Becagli, David Cappelletti, and Franco Belosi
Atmos. Chem. Phys., 21, 14725–14748, https://doi.org/10.5194/acp-21-14725-2021, https://doi.org/10.5194/acp-21-14725-2021, 2021
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This study aims to add to the still scant ice-nucleating particle (INP) observations in the Arctic environment, investigating INP concentrations and potential sources, during spring and summertime, at the ground-level site of GVB. The lack of a clear concentration seasonal trend, in contrast with previous works, shows an important interannual variability of Arctic INP sources, which may be both terrestrial and marine, outside the Arctic haze period.
Cited articles
Baguskas, S. A., Still, C. J., Fischer, D. T., D'Antonio, C. M., and King, J. Y.: Coastal fog during summer drought improves the water status of sapling trees more than adult trees in a California pine forest, Oecologia, 181, 137–148, https://doi.org/10.1007/s00442-016-3556-y, 2016. a
Balmes, J. R., Fine, J. M., Gordon, T., and Sheppard, D.: Potential bronchoconstrictor stimuli in acid fog, Environ. Health Perspect., 79, 163–166, https://doi.org/10.1289/ehp.8979163, 1989. a
Baumgardner, D., Avallone, L., Bansemer, A., Borrmann, S., Brown, P., Bundke, U., Chuang, P. Y., Cziczo, D., Field, P., Gallagher, M., Gayet, J.-F., Heymsfield, A., Korolev, A., Krämer, M., McFarquhar, G., Mertes, S., Möhler, O., Lance, S., Lawson, P., Petters, M. D., Pratt, K., Roberts, G., Rogers, D., Stetzer, O., Stith, J., Strapp, W., Twohy, C., and Wendisch, M.: IN SITU, AIRBORNE INSTRUMENTATION: Addressing and Solving Measurement Problems in Ice Clouds, B. Am. Meteorol. Soc., 93, ES29–ES34, 2012. a
Bhandari, J., China, S., Chandrakar, K. K., Kinney, G., Cantrell, W., Shaw, R. A., Mazzoleni, L. R., Girotto, G., Sharma, N., Gorkowski, K., Gilardoni S., Decesari S., Facchini M. C., Zanca N., Pavese G., Esposito F., Dubey M. K., Aiken A. C., Chakrabarty R. K., Moosmüller H., Onasch T. B., Zaveri R. A., Scarnato B. V., Fialho P., and Mazzoleni C.: Extensive soot compaction by cloud processing from laboratory and field observations, Sci. Rep., 9, 11824, https://doi.org/10.1038/s41598-019-48143-y, 2019. a
Bigi, A. and Ghermandi, G.: Trends and variability of atmospheric PM2.5 and PM10–2.5 concentration in the Po Valley, Italy, Atmos. Chemi. Phys., 16, 15777–15788, https://doi.org/10.5194/acp-16-15777-2016, 2016. a
Boutle, I., Price, J., Kudzotsa, I., Kokkola, H., and Romakkaniemi, S.: Aerosol–fog interaction and the transition to well-mixed radiation fog, Atmos. Chem. Phys. 18, 7827–7840, https://doi.org/10.5194/acp-18-7827-2018, 2018. a
Boutle, I., Angevine, W., Bao, J.-W., Bergot, T., Bhattacharya, R., Bott, A., Ducongé, L., Forbes, R., Goecke, T., Grell, E., Hill, A., Igel, A. L., Kudzotsa, I., Lac, C., Maronga, B., Romakkaniemi, S., Schmidli, J., Schwenkel, J., Steeneveld, G.-J., and Vié, B.: Demistify: a large-eddy simulation (LES) and single-column model (SCM) intercomparison of radiation fog, Atmos. Chem. Phys., 22, 319–333, https://doi.org/10.5194/acp-22-319-2022, 2022. a, b
Costabile, F., Decesari, S., Vecchi, R., Lucarelli, F., Curci, G., Massabò, D., Rinaldi, M., Gualtieri, M., Corsini, E., Menegola, E., Canepari, S., Massimi, L., Argentini, S., Busetto, M., Di Iulio, G., Di Liberto, L., Paglione, M., Petenko, I., Russo, M., Marinoni, A., Casasanta, G., Valentini, S., Bernardoni, V., Crova, F., Valli, G., Forello, A. C., Giardi, F., Nava, S., Pazzi, G., Prati, P., Vernocchi, V., La Torretta, T., Petralia, E., Stracquadanio, M., Zanini, G., Melzi, G., Nozza, E., Iulini, M., Caruso, D., Cioffi, L., Imperato, G., Giavarini, F., Battistoni, M., Di Renzo, F., Frezzini, M. A., Perrino, C., and Facchini, M. C.: On the Redox-Activity and Health-Effects of Atmospheric Primary and Secondary Aerosol: Phenomenology, Atmosphere, 13, https://doi.org/10.3390/atmos13050704, 2022. a
Daellenbach, K. R., Uzu, G., Jiang, J., Cassagnes, L.-E., Leni, Z., Vlachou, A., Stefenelli, G., Canonaco, F., Weber, S., Segers, A., Kuenen J. J. P., Schaap M., Favez O., Albinet A., Aksoyoglu S., Dommen J., Baltensperger U., Geiser M., El Haddad I., Jaffrezo J.-L., and Prévôt A. S. H.: Sources of particulate-matter air pollution and its oxidative potential in Europe, Nature, 587, 414–419, 2020. a
Deardorff, J. W.: Three-dimensional numerical study of turbulence in an entraining mixed layer, Bound.-Lay. Meteorol., 7, 199–226, 1974. a
DeCarlo, P. F., Kimmel, J. R., Trimborn, A., Northway, M. J., Jayne, J. T., Aiken, A. C., Gonin, M., Fuhrer, K., Horvath, T., Docherty, K. S., Worsnop, D. R., and Jimenez, J. L.: Field-Deployable, High-Resolution, Time-of-Flight Aerosol Mass Spectrometer, Anal. Chem., 78, 8281–8289, https://doi.org/10.1021/ac061249n, 2006. a
Decesari, S., Sowlat, M. H., Hasheminassab, S., Sandrini, S., Gilardoni, S., Facchini, M. C., Fuzzi, S., and Sioutas, C.: Enhanced toxicity of aerosol in fog conditions in the Po Valley, Italy, Atmos. Chem. Phys., 17, 7721–7731, https://doi.org/10.5194/acp-17-7721-2017, 2017. a, b
Ding, H., Neuberger, A., Ranjan, R., Mattsson, F., Haberstock, L., Baumgardner, D., Decesari, S., Ekman, A. M. L., Hughes, D., Mohr, C., Paglione, M., Riipinen, I., Rinaldi, M., and Zieger, P.: Large-eddy simulation outputs of radiation fog events during the FAIRARI campaign, Po Valley, Italy, February 2022, Dataset version 1, Bolin Centre Database [data set], https://doi.org/10.17043/fairari-2021-2022-les1-1, 2025. a
Ding, H., Neuberger, A., Ranjan, R., Mattsson, F., Heikkinen, L., Mansour, K., Decesari, S., Mohr, C., Pérez, A. B., Mastroianni, N., Zieger, P., Riipinen, I., and Ekman, A. M. L.: The Importance of Aerosol and Droplet Microphysics for the Properties and Life Cycle of Radiation Fog in the Po Valley, EGUsphere [preprint], https://doi.org/10.5194/egusphere-2025-6435, 2026. a
EEA: Air Quality in Europe 2020 – Report No 09/20, Tech. rep., European Environment Agency, https://www.eea.europa.eu//publications/air-quality-in-europe-2020-report (last access: 23 June 2026), 2020. a
Egli, S., Thies, B., and Bendix, J.: A spatially explicit and temporally highly resolved analysis of variations in fog occurrence over Europe, Q. J. Roy. Meteorol. Soc., 145, 1721–1740, https://doi.org/10.1002/qj.3522, 2019. a
Ekman, A. M. L., Wang, C., Stróm, J., and Krejci, R.: Explicit Simulation of Aerosol Physics in a Cloud-Resolving Model: Aerosol Transport and Processing in the Free Troposphere, J. Atmos. Sci., 63, 682–696, https://doi.org/10.1175/JAS3645.1, 2006. a
Elias, T., Haeffelin, M., Drobinski, P., Gomes, L., Rangognio, J., Bergot, T., Chazette, P., Raut, J.-C., and Colomb, M.: Particulate contribution to extinction of visible radiation: Pollution, haze, and fog, Atmos. Res., 92, 443–454, https://doi.org/10.1016/j.atmosres.2009.01.006, 2009. a
Elias, T., Dupont, J.-C., Hammer, E., Hoyle, C. R., Haeffelin, M., Burnet, F., and Jolivet, D.: Enhanced extinction of visible radiation due to hydrated aerosols in mist and fog, Atmos. Chem. Phys., 15, 6605–6623, https://doi.org/10.5194/acp-15-6605-2015, 2015. a
Facchini, M. C., Fuzzi, S., Zappoli, S., Andracchio, A., Gelencsér, A., Kiss, G., Krivácsy, Z., Mészáros, E., Hansson, H.-C., Alsberg, T., and Zebühr, Y.: Partitioning of the organic aerosol component between fog droplets and interstitial air, J. Geophys. Res.-Atmos., 104, 26821–26832, https://doi.org/10.1029/1999JD900349, 1999. a
Facchini, M. C., Decesari, S., Rinaldi, M., Carbone, C., Finessi, E., Mircea, M., Fuzzi, S., Moretti, F., Tagliavini, E., Ceburnis, D., and O'Dowd, C. D.: Important Source of Marine Secondary Organic Aerosol from Biogenic Amines, Environ. Sci. Technol., 42, 9116–9121, https://doi.org/10.1021/es8018385, 2008. a
Fernando, H. J. S., Gultepe, I., Dorman, C., Pardyjak, E., Wang, Q., Hoch, S. W., Richter, D., Creegan, E., Gaberšek, S., Bullock, T., Hocut, C., Chang, R., Alappattu, D., Dimitrova, R., Flagg, D., Grachev, A., Krishnamurthy, R., Singh, D. K., Lozovatsky, I., Nagare, B., Sharma, A., Wagh, S., Wainwright, C., Wroblewski, M., Yamaguchi, R., Bardoel, S., Coppersmith, R. S., Chisholm, N., Gonzalez, E., Gunawardena, N., Hyde, O., Morrison, T., Olson, A., Perelet, A., Perrie, W., Wang, S., and Wauer, B.: C-FOG: Life of Coastal Fog, B. Am. Meteorol. Soc., 102, E244–E272, https://doi.org/10.1175/BAMS-D-19-0070.1, 2021. a
Frank, G., Martinsson, B. G., Cederfelt, S.-I., Berg, O. H., Swietlicki, E., Wendisch, M., Yuskiewicz, B., Heintzenberg, J., Wiedensohler, A., Orsini, D., Stratmann F., Laj P., and Ricci L.: Droplet formation and growth in polluted fogs, Contrib. Atmos. Phys., 71, 65–85, 1998. a
Fu, Q. and Liou, K. N.: Parameterization of the Radiative Properties of Cirrus Clouds, J. Atmos. Sci., 50, 2008–2025, https://doi.org/10.1175/1520-0469(1993)050<2008:POTRPO>2.0.CO;2, 1993. a
Fuzzi, S., Orsi, G., and Mariotti, M.: Radiation fog liquid water acidity at a field station in the Po Valley, J. Aerosol Sci., 14, 135–138, https://doi.org/10.1016/0021-8502(83)90037-X, 1983. a
Fuzzi, S., Facchini, M. C., Orsi, G., Lind, J. A., Wobrock, W., Kessel, M., Maser, R., Jaeschke, W., Enderle, K. H., Arends, B. G., Berner, A., Solly, I., Kruisz, C., Reischl, G., Pahl, S., Kaminski, U., Winkler, P., Ogren, J. A., Noone, K. J., Hallberg, A., Fierlinger-Oberlinninger, H., Puxbaum, H., Marzorati, A., Hansson, H.-C., Wiedensohler, A., Svenningsson, I. B., Martinsson, B. G., Schell, D., and Georgii, H. W.: The Po Valley Fog Experiment 1989, Tellus B, 44, 448–468, https://doi.org/10.1034/j.1600-0889.1992.t01-4-00002.x, 1992. a, b
Gao, F. and Han, L.: Implementing the Nelder-Mead simplex algorithm with adaptive parameters, Comput. Optimiz. Appl., 51, 259–277, 2012. a
Gerber, H. E.: Microstructure of a Radiation Fog, J. Atmos. Sci., 38, 454–458, https://doi.org/10.1175/1520-0469(1981)038<0454:MOARF>2.0.CO;2, 1981. a
Ghude, S. D., Jenamani, R. K., Kulkarni, R., Wagh, S., Dhangar, N. G., Parde, A. N., Acharja, P., Lonkar, P., Govardhan, G., Yadav, P., Vispute, A., Debnath, S., Lal, D. M., Bisht, D. S., Jena, C., Pawar, P. V., Dhankhar, S. S., Sinha, V., Chate, D. M., Safai, P. D., Nigam, N., Konwar, M., Hazra, A., Dharmaraj, T., Gopalkrishnan, V., Padmakumari, B., Gultepe, I., Biswas, M., Karipot, A. K., Prabhakaran, T., Nanjundiah, R. S., and Rajeevan, M.: WiFEX: Walk into the Warm Fog over Indo-Gangetic Plain Region, B. Am. Meteorol. Soc., 104, E980–E1005, https://doi.org/10.1175/BAMS-D-21-0197.1, 2023. a, b, c
Gilardoni, S., Massoli, P., Giulianelli, L., Rinaldi, M., Paglione, M., Pollini, F., Lanconelli, C., Poluzzi, V., Carbone, S., Hillamo, R., Russell, L. M., Facchini, M. C., and Fuzzi, S.: Fog scavenging of organic and inorganic aerosol in the Po Valley, Atmos. Chem. Phys., 14, 6967–6981, https://doi.org/10.5194/acp-14-6967-2014, 2014. a
Gilardoni, S., Massoli, P., Paglione, M., Giulianelli, L., Carbone, C., Rinaldi, M., Decesari, S., Sandrini, S., Costabile, F., Gobbi, G. P., Pietrogrande, M. C., Visentin, M., Scotto, F., Fuzzi, S., and Facchini, M. C.: Direct observation of aqueous secondary organic aerosol from biomass-burning emissions, P. Natl. Acad. Sci. USA, 113, 10013–10018, https://doi.org/10.1073/pnas.1602212113, 2016. a
Gilardoni, S., Tarozzi, L., Sandrini, S., Ielpo, P., Contini, D., Putaud, J.-P., Cavalli, F., Poluzzi, V., Bacco, D., Leonardi, C., Genga, A., Langone, L., and Fuzzi, S.: Reconstructing elemental carbon long-term trend in the Po Valley (Italy) from fog water samples, Atmosphere, 11, 580, https://doi.org/10.3390/atmos11060580, 2020. a
Giulianelli, L., Gilardoni, S., Tarozzi, L., Rinaldi, M., Decesari, S., Carbone, C., Facchini, M., and Fuzzi, S.: Fog occurrence and chemical composition in the Po Valley over the last twenty years, Atmos. Environ., 98, 394–401, https://doi.org/10.1016/j.atmosenv.2014.08.080, 2014. a, b, c, d
Glantz, P., Fawole, O. G., Ström, J., Wild, M., and Noone, K. J.: Unmasking the Effects of Aerosols on Greenhouse Warming Over Europe, J.f Geophys. Res.-Atmos., 127, e2021JD035889, https://doi.org/10.1029/2021JD035889, 2022. a
Gultepe, I., Tardif, R., Michaelides, S. C., Cermak, J., Bott, A., Bendix, J., Müller, M. D., Pagowski, M., Hansen, B., Ellrod, G., Jacobs, W., Toth G., and Cober S. G.: Fog research: A review of past achievements and future perspectives, Pure Appl. Geophys., 164, 1121–1159, https://doi.org/10.1007/s00024-007-0211-x, 2007. a
Gultepe, I., Kuhn, T., Pavolonis, M., Calvert, C., Gurka, J., Heymsfield, A. J., Liu, P. S. K., Zhou, B., Ware, R., Ferrier, B., Milbrandt, J., and Bernstein, B.: Ice Fog in Arctic During FRAM–Ice Fog Project: Aviation and Nowcasting Applications, B. Am. Meteorol. Soc., 95, 211–226, https://doi.org/10.1175/BAMS-D-11-00071.1, 2014. a
Guyot, G., Gourbeyre, C., Febvre, G., Shcherbakov, V., Burnet, F., Dupont, J.-C., Sellegri, K., and Jourdan, O.: Quantitative evaluation of seven optical sensors for cloud microphysical measurements at the Puy-de-Dôme Observatory, France, Atmos. Meas. Tech., 8, 4347–4367, https://doi.org/10.5194/amt-8-4347-2015, 2015. a, b
Haeffelin, M., Bergot, T., Elias, T., Tardif, R., Carrer, D., Chazette, P., Colomb, M., Drobinski, P., Dupont, E., Dupont, J.-C., Gomes, L., Musson-Genon, L., Pietras, C., Plana-Fattori, A., Protat, A., Rangognio, J., Raut, J.-C., Rémy, S., Richard, D., Sciare, J., and Zhang, X.: Parisfog: Shedding new Light on Fog Physical Processes, B. Am. Meteorol. Soc., 91, 767–783, https://doi.org/10.1175/2009BAMS2671.1, 2010. a, b
Hamed, A., Joutsensaari, J., Mikkonen, S., Sogacheva, L., Dal Maso, M., Kulmala, M., Cavalli, F., Fuzzi, S., Facchini, M. C., Decesari, S., Mircea, M., Lehtinen, K. E. J., and Laaksonen, A.: Nucleation and growth of new particles in Po Valley, Italy, Atmos. Chem. Phys., 7, 355–376, https://doi.org/10.5194/acp-7-355-2007, 2007. a
Hamilton, W. J. and Seely, M. K.: Fog basking by the Namib Desert beetle, Onymacris unguicularis, Nature, 262, 284–285, 1976. a
Hammer, E., Gysel, M., Roberts, G. C., Elias, T., Hofer, J., Hoyle, C. R., Bukowiecki, N., Dupont, J.-C., Burnet, F., Baltensperger, U., and Weingartner, E.: Size-dependent particle activation properties in fog during the ParisFog 2012/13 field campaign, Atmos. Chem. Phys., 14, 10517–10533, https://doi.org/10.5194/acp-14-10517-2014, 2014. a, b, c, d, e, f
Heintzenberg, J., Wendisch, M., Yuskiewicz, B., Orsini, D., Wiedensohler, A., Stratmann, F., Frank, G., Martinsson, B. G., Schell, D., Fuzzi, S., and Orsi G.: Characteristics of haze, mist and fog, Contrib. Atmos. Phys., 71, 21–31, 1998. a
Hersbach, H., Bell, B., Berrisford, P., Biavati, G., Horányi, A., Muñoz Sabater, J., Nicolas, J., Peubey, C., Radu, R., Rozum, I., Schepers, D., Simmons, A., Soci, C., Dee, D., and Thépaut, J.-N.: ERA5 hourly data on pressure levels from 1940 to present, CDS [data set], https://doi.org/10.24381/cds.bd0915c6, 2023. a
Hudson, J. G.: Relationship Between Fog Condensation Nuclei and Fog Microstructure, Journal of Atmospheric Sciences, 37, 1854 – 1867, https://doi.org/10.1175/1520-0469(1980)037<1854:RBFCNA>2.0.CO;2, 1980. a, b
Jurányi, Z., Gysel, M., Weingartner, E., DeCarlo, P. F., Kammermann, L., and Baltensperger, U.: Measured and modelled cloud condensation nuclei number concentration at the high alpine site Jungfraujoch, Atmos. Chem. Phys., 10, 7891–7906, https://doi.org/10.5194/acp-10-7891-2010, 2010. a
Karlsson, L., Baccarini, A., Duplessis, P., Baumgardner, D., Brooks, I. M., Chang, R. Y.-W., Dada, L., Dällenbach, K. R., Heikkinen, L., Krejci, R., Leaitch, W. R., Leck, C., Partridge, D. G., Salter, M. E., Wernli, H., Wheeler, M. J., Schmale, J., and Zieger, P.: Physical and Chemical Properties of Cloud Droplet Residuals and Aerosol Particles During the Arctic Ocean 2018 Expedition, J. Geophys. Res.-Atmos., 127, e2021JD036383, https://doi.org/10.1029/2021JD036383, 2022. a
Kasten, F.: Visibility forecast in the phase of pre-condensation, Tellus, 21, 631–635, https://doi.org/10.1111/j.2153-3490.1969.tb00469.x, 1969. a
Klemm, O. and Lin, N.-H.: What Causes Observed Fog Trends: Air Quality or Climate Change?, Aerosol Air Qual. Res., 16, 1131–1142, https://doi.org/10.4209/aaqr.2015.05.0353, 2016. a
Klemm, O., Wang, S.-H., Lin, P.-H., and Lin, N.-H.: Visibility Reduction in Fog: The Role of Activation, Aerosol Air Qual. Res., 25, 54, https://doi.org/10.1007/s44408-025-00055-5, 2025. a
Köhler, H.: The nucleus in and the growth of hygroscopic droplets, Trans. Faraday Soc., 32, 1152–1161, https://doi.org/10.1039/TF9363201152, 1936. a
Koschmieder, H.: Theorie der horizontalen sichtweite, Beitrage zur Physik der Freien Atmosphare, Meteorol. Z., 12, 3353–3353, 1924. a
Kunkel, B. A.: Parameterization of Droplet Terminal Velocity and Extinction Coefficient in Fog Models, J. Appl. Meteorol. Clim., 23, 34–41, https://doi.org/10.1175/1520-0450(1984)023<0034:PODTVA>2.0.CO;2, 1984. a, b, c
Lakra, K. and Avishek, K.: A review on factors influencing fog formation, classification, forecasting, detection and impacts, Rendiconti Lincei. Scienze Fisiche e Naturali, 33, 319–353, 2022. a
Lampilahti, J., Manninen, H E., Nieminen, T., Mirme, S., Ehn, M., Pullinen, I., Leino, K., Schobesberger, S., Kangasluoma, J., Kontkanen, J., Järvinen, E., Väänänen, R., Yli-Juuti, T., Krejci, R., Lehtipalo, K., Levula, J., Mirme, A., Decesari, S., Tillmann, R., Worsnop, D. R., Rohrer, F., Kiendler-Scharr, A., Petäjä, T., Kerminen, V.-M., Mentel, T. F., and Kulmala, M.: Zeppelin-led study on the onset of new particle formation in the planetary boundary layer, Atmos. Chem. Phys., 21, 12649–12663, https://doi.org/10.5194/acp-21-12649-2021, 2021. a
Leigh, R. J., Drake, L., and Thampapillai, D. J.: An Economic Analysis of Terminal Aerodrome Forecasts with Special Reference to Sydney Airport, J. Trans. Econ. Policy, 32, 377–392, 1998. a
Liu, D., Li, Z., Yan, W., and Li, Y.: Advances in fog microphysics research in China, Asia-Pacif. J. Atmos. Sci., 53, 131–148, 2017. a
Liu, Q., Shen, X., Sun, J., Zhang, Y., Qi, B., Ma, Q., Han, L., Xu, H., Hu, X., Lu, J., Liu, S., Yu, A., Liang, L., Gao, Q., Wang, H., Che, H., and Zhang, X.: Characterization of fog microphysics and their relationships with visibility at a mountain site in China, Atmos. Chem. Phys., 25, 3253–3267, https://doi.org/10.5194/acp-25-3253-2025, 2025. a
Maalick, Z., Kühn, T., Korhonen, H., Kokkola, H., Laaksonen, A., and Romakkaniemi, S.: Effect of aerosol concentration and absorbing aerosol on the radiation fog life cycle, Atmos. Environ. 133, 26–33, https://doi.org/10.1016/j.atmosenv.2016.03.018, 2016. a
Maier, F., Bendix, J., and Thies, B.: Development and application of a method for the objective differentiation of fog life cycle phases, Tellus B, 65, 19971, https://doi.org/10.3402/tellusb.v65i0.19971, 2013. a
Manara, V., Brunetti, M., Gilardoni, S., Landi, T. C., and Maugeri, M.: 1951–2017 changes in the frequency of days with visibility higher than 10 km and 20 km in Italy, Atmos. Environ., 214, 116861, https://doi.org/10.1016/j.atmosenv.2019.116861, 2019. a
Mattsson, F., Neuberger, A., Heikkinen, L., Gramlich, Y., Paglione, M., Rinaldi, M., Decesari, S., Zieger, P., Riipinen, I., and Mohr, C.: Enrichment of organic nitrogen in fog residuals observed in the Italian Po Valley, Atmos. Chem. Phys., 25, 7973–7989, https://doi.org/10.5194/acp-25-7973-2025, 2025a. a, b, c, d, e
Mattsson, F., Neuberger, A., Heikkinen, L., Zieger, P., and Mohr, C.: Aerosol chemical composition measured during the FAIRARI campaign, Po Valley, Italy, February–April 2022, Dataset version 1, Bolin Centre Database [data set], https://doi.org/10.17043/fairari-2021-2022-aerosol-spams-1, 2025b. a
Mazoyer, M., Burnet, F., Denjean, C., Roberts, G. C., Haeffelin, M., Dupont, J.-C., and Elias, T.: Experimental study of the aerosol impact on fog microphysics, Atmos.Chem. Phys., 19, 4323–4344, https://doi.org/10.5194/acp-19-4323-2019, 2019. a, b, c, d
Mazoyer, M., Burnet, F., and Denjean, C.: Experimental study on the evolution of droplet size distribution during the fog life cycle, Atmos. Chem. Phys., 22, 11305–11321, https://doi.org/10.5194/acp-22-11305-2022, 2022. a, b
Mitchell, D., Henschel, J. R., Hetem, R. S., Wassenaar, T. D., Strauss, W. M., Hanrahan, S. A., and Seely, M. K.: Fog and fauna of the Namib Desert: past and future, Ecosphere, 11, e02996, https://doi.org/10.1002/ecs2.2996, 2020. a
Morrison, H. and Grabowski, W. W.: Modeling Supersaturation and Subgrid-Scale Mixing with Two-Moment Bulk Warm Microphysics, J. Atmos. Sci., 65, 792–812, https://doi.org/10.1175/2007JAS2374.1, 2008. a
Neuberger, A., Mattsson, F., and Zieger, P.: Aerosol particle number size distribution measured during the FAIRARI campaign, Po valley, Italy, February–April 2022, Dataset version 1, Bolin Centre Database [data set], https://doi.org/10.17043/fairari-2021-2022-aerosol-dmps1-1, 2024a. a
Neuberger, A., Mattsson, F., and Zieger, P.: Equivalent black carbon concentration measured during the FAIRARI campaign, Po valley, Italy, February–April 2022, Dataset version 1, Bolin Centre Database [data set], https://doi.org/10.17043/fairari-2021-2022-aerosol-maap2-1, 2024b. a
Neuberger, A., Decesari, S., Aktypis, A., Andersen, H., Baumgardner, D., Bianchi, F., Busetto, M., Cai, J., Cermak, J., Dipu, S., Ekman, A., Fuzzi, S., Gramlich, Y., Haslett, S. L., Heikkinen, L., Joutsensaari, J., Kaltsonoudis, C., Kangasluoma, J., Krejci, R., Lupi, A., Marinoni, A., Matrali, A., Mattsson, F., Mohr, C., Nenes, A., Paglione, M., Pandis, S. N., Patel, A., Riipinen, I., Rinaldi, M., Steimer, S. S., Stolzenburg, D., Sulo, J., Vasilakopoulou, C. N., and Zieger, P.: From Molecules to Droplets: The Fog and Aerosol Interaction Research Italy (FAIRARI) 2021/22 Campaign, B. Am. Meteorol. Soc., 106, E23–E50, https://doi.org/10.1175/BAMS-D-23-0166.1, 2025. a, b, c, d, e, f, g
Neuberger, A., Haberstock, L., Ranjan, R., Riipinen, I., and Zieger, P.: The fog and aerosol size distribution measured during the FAIRARI campaign, Po valley, Italy, February–April 2022, Dataset version 1, Bolin Centre Database [data set], https://doi.org/10.17043/fairari-2021-2022-droplet-size-1, 2026a. a
Neuberger, A., Ranjan, R., Riipinen, I., and Zieger, P.: Cloud condensation nuclei concentrations measured during the FAIRARI campaign, Po valley, Italy, February–April 2022, Dataset version 1, Bolin Centre Database [data set], https://doi.org/10.17043/fairari-2021-2022-ccn-concentrations-1, 2026b. a
Noone, K. J., Ogren, J. A., Hallberg, A., Heintzenberg, J., Strom, J., Hansson, H.-C., Svenningsson, B., Wiedensohler, A., Fuzzi, S., Facchini, M. C., Arends, B. G., and Berner A.: Changes in aerosol size- and phase distributions due to physical and chemical processes in fog, Tellus B, 44, 489–504, https://doi.org/10.3402/tellusb.v44i5.15563, 1992. a, b, c, d
Ogren, J., Noone, K., Hallberg, A., Heintzenberg, J., Schell, D., Berner, A., Solly, I., Kruisz, C., Reischl, G., Arends, B. G., and Wobrock, W.: Measurements of the size dependence of the concentration of nonvolatile material in fog droplets, Tellus B, 44, 570–580, https://doi.org/10.3402/tellusb.v44i5.15569, 1992. a
Oliphant, A. J., Baguskas, S. A., and Fernandez, D. M.: Impacts of low cloud and fog on surface radiation fluxes for ecosystems in coastal California, Theor. Appl. Climatol., 144, 239–252, https://doi.org/10.1007/s00704-021-03518-y, 2021. a
Onasch, T., Trimborn, A., Fortner, E., Jayne, J., Kok, G., Williams, L., Davidovits, P., and Worsnop, D.: Soot Particle Aerosol Mass Spectrometer: Development, Validation, and Initial Application, Aerosol Sci. Tech., 46, 804–817, https://doi.org/10.1080/02786826.2012.663948, 2012. a
Paglione, M., Gilardoni, S., Rinaldi, M., Decesari, S., Zanca, N., Sandrini, S., Giulianelli, L., Bacco, D., Ferrari, S., Poluzzi, V., Scotto, F., Trentini, A., Poulain, L., Herrmann, H., Wiedensohler, A., Canonaco, F., Prévôt, A. S. H., Massoli, P., Carbone, C., Facchini, M. C., and Fuzzi, S.: The impact of biomass burning and aqueous-phase processing on air quality: a multi-year source apportionment study in the Po Valley, Italy, Atmos. Chem. Phys., 20, 1233–1254, https://doi.org/10.5194/acp-20-1233-2020, 2020. a, b
Paglione, M., Rinaldi, M., Busetto, M., Decesari, S., and Marinoni, A.: Interstitial equivalent black carbon concentration measured during the FAIRARI campaign, Po valley, Italy, February–May 2022, Dataset version 1, Bolin Centre Database [data set], https://doi.org/10.17043/fairari-2021-2022-aerosol-ebc-pm25-1, 2026a. a
Paglione, M., Decesari, S., Neuberger, A., Ranjan, R., Riipinen, I., and Zieger, P.: Meteorological parameters measured during the FAIRARI campaign, Po Valley, Italy, February–April 2022. Dataset version 1, Bolin Centre Database [data set], https://doi.org/10.17043/fairari-2021-2022-meteorological-1, 2026b. a
Paglione, M., Rinaldi, M., Decesari, S., and Mansour, K.: Air liquid water Content (LWC) during the FAIRARI campaign, Po valley, Italy, February–April 2022, Dataset version 1, Bolin Centre Database [data set], https://doi.org/10.17043/fairari-2021-2022-lwc-1, 2026c. a
Pagowski, M., Gultepe, I., and King, P.: Analysis and Modeling of an Extremely Dense Fog Event in Southern Ontario, J. Appl. Meteorol., 43, 3–16, https://doi.org/10.1175/1520-0450(2004)043<0003:AAMOAE>2.0.CO;2, 2004. a
Patel, A. and Rastogi, N.: Oxidative potential of ambient fine aerosol over a semi-urban site in the Indo-Gangetic Plain, Atmos. Environ., 175, 127–134, https://doi.org/10.1016/j.atmosenv.2017.12.004, 2018. a
Petters, M. D. and Kreidenweis, S. M.: A single parameter representation of hygroscopic growth and cloud condensation nucleus activity, Atmos. Chem. Phys., 7, 1961–1971, https://doi.org/10.5194/acp-7-1961-2007, 2007. a, b
Petzold, A. and Schönlinner, M.: Multi-angle absorption photometry – a new method for the measurement of aerosol light absorption and atmospheric black carbon, J. Aerosol Sci., 35, 421–441, https://doi.org/10.1016/j.jaerosci.2003.09.005, 2004. a
Petzold, A., Kramer, H., and Schönlinner, M.: Continuous Measurement of Atmospheric Black Carbon Using a Multi-angle Absorption Photometer, Environ. Sci. Pollut. Res., 4, 78–82, 2002. a
Pinnick, R. G., Hoihjelle, D. L., Fernandez, G., Stenmark, E. B., Lindberg, J. D., Hoidale, G. B., and Jennings, S. G.: Vertical Structure in Atmospheric Fog and Haze and Its Effects on Visible and Infrared Extinction, J. Atmos. Sci., 35, 2020–2032, https://doi.org/10.1175/1520-0469(1978)035<2020:VSIAFA>2.0.CO;2, 1978. a
Price, J. D., Lane, S., Boutle, I. A., Smith, D. K. E., Bergot, T., Lac, C., Duconge, L., McGregor, J., Kerr-Munslow, A., Pickering, M., and Clark, R.: LANFEX: A Field and Modeling Study to Improve Our Understanding and Forecasting of Radiation Fog, B. Am. Meteorol. Soc., 99, 2061–2077, https://doi.org/10.1175/BAMS-D-16-0299.1, 2018. a
Quan, J., Zhang, Q., He, H., Liu, J., Huang, M., and Jin, H.: Analysis of the formation of fog and haze in North China Plain (NCP), Atmos. Chem. Phys., 11, 8205–8214, https://doi.org/10.5194/acp-11-8205-2011, 2011.
Ranjan, R., Dewey, M., Heikkinen, L., Ahonen, L. R., Luoma, K., Bowen, P., Petäjä, T., Ekman, A. M. L., Partridge, D. G., and Riipinen, I.: Optimizing CCN predictions through inferred modal aerosol composition – a boreal forest case study, Atmos. Chem. Phys., 25, 17275–17300, https://doi.org/10.5194/acp-25-17275-2025, 2025. a
Ricci, L., Fuzzi, S., Laj, P., Lazzari, A., Orsi, G., Berner, A., Günther, A., Jaeschke, W., Wendisch, M., and Arends, B.: Gas-liquid equilibria in polluted fog, Contrib. Atmos. Phys., 71, 159–170, 1998. a
Rinaldi, M., Paglione, M., and Decesari, S.: Interstitial aerosol chemical composition measured by HR-TOF-AMS during the FAIRARI campaign, Po Valley, Italy, Feb.–May 2022, Dataset version 1m Bolin Centre Database [data set], https://doi.org/10.17043/fairari-2021-2022-aerosol-chemical-pm25-1, 2026. a
Rose, D., Gunthe, S. S., Mikhailov, E., Frank, G. P., Dusek, U., Andreae, M. O., and Pöschl, U.: Calibration and measurement uncertainties of a continuous-flow cloud condensation nuclei counter (DMT-CCNC): CCN activation of ammonium sulfate and sodium chloride aerosol particles in theory and experiment, Atmos. Chem. Phys., 8, 1153–1179, https://doi.org/10.5194/acp-8-1153-2008, 2008. a
Savre, J., Ekman, A. M. L., and Svensson, G.: Technical note: Introduction to MIMICA, a large-eddy simulation solver for cloudy planetary boundary layers, J. Adv. Model. Earth Syst., 6, 630–649, https://doi.org/10.1002/2013MS000292, 2014. a, b
Scotto, F., Bacco, D., Lasagni, S., Trentini, A., Poluzzi, V., and Vecchi, R.: A multi-year source apportionment of PM2.5 at multiple sites in the southern Po Valley (Italy), Atmos. Pollut. Res., 12, 101192, https://doi.org/10.1016/j.apr.2021.101192, 2021. a
Seely, M. K. and Hamilton, W. J.: Fog catchment sand trenches constructed by tenebrionid beetles, Lepidochora, from the Namib Desert, Science, 193, 484–486, 1976. a
Seifert, A. and Beheng, K. D.: A two-moment cloud microphysics parameterization for mixed-phase clouds. Part 1: Model description, Meteorol. Atmos. Phys., 92, 45–66, 2006. a
Shankar, A. and Sahana, B. C.: Early warning of low visibility using the ensembling of machine learning approaches for aviation services at Jay Prakash Narayan International (JPNI) Airport Patna, SN Appl. Sci., 5, 132, https://doi.org/10.1007/s42452-023-05350-7, 2023. a
Shen, C., Zhao, C., Ma, N., Tao, J., Zhao, G., Yu, Y., and Kuang, Y.: Method to Estimate Water Vapor Supersaturation in the Ambient Activation Process Using Aerosol and Droplet Measurement Data, J. Geophys. Res.-Atmos., 123, 10606–10619, https://doi.org/10.1029/2018JD028315, 2018. a, b, c, d, e, f, g
Spänkuch, D., Hellmuth, O., and Görsdorf, U.: What Is a Cloud? Toward a More Precise Definition, B. Am. Meteorol. Soc., 103, E1894–E1929, https://doi.org/10.1175/BAMS-D-21-0032.1, 2022. a
Spiegel, J., Zieger, P., Bukowiecki, N., Hammer, E., Weingartner, E., and Eugster, W.: Evaluating the capabilities and uncertainties of droplet measurements for the fog droplet spectrometer (FM-100), Atmos. Meas. Tech., 5, 2237–2260, https://doi.org/10.5194/amt-5-2237-2012, 2012. a, b, c, d
Steeneveld, G. J., Ronda, R. J., and Holtslag, A. A. M.: The Challenge of Forecasting the Onset and Development of Radiation Fog Using Mesoscale Atmospheric Models, Bound.-Lay. Meteorol., 154, 265–289, https://doi.org/10.1007/s10546-014-9973-8, 2015. a
Stokes, R. H. and Robinson, R. A.: Interactions in Aqueous Nonelectrolyte Solutions. I. Solute-Solvent Equilibria, J. Phys. Chem., 70, 2126–2131, https://doi.org/10.1021/j100879a010, 1966. a
Stolaki, S., Haeffelin, M., Lac, C., Dupont, J.-C., Elias, T., and Masson, V.: Influence of aerosols on the life cycle of a radiation fog event. A numerical and observational study, Atmos. Res., 151, 146–161, https://doi.org/10.1016/j.atmosres.2014.04.013, 2015. a
Sueper, D.: ToF-AMS Data Analysis Software Webpage, http://cires1.colorado.edu/jimenez-group/wiki/index.php/ToF-AMS_Analysis_Software (last access: 8 February 2024), 2024. a
Svenningsson, I. B., Hansson, H.-C., Wiedensohler, A., Ogren, J. A., Noone, K. J., and Hallberg, A.: Hygroscopic growth of aerosol particles in the Po Valley, Tellus B, 44, 556–569, https://doi.org/10.1034/j.1600-0889.1992.t01-1-00009.x, 1992. a, b, c
Tardif, R. and Rasmussen, R. M.: Event-Based Climatology and Typology of Fog in the New York City Region, J. Appl. Meteorol. Clim., 46, 1141–1168, https://doi.org/10.1175/JAM2516.1, 2007. a
Twomey, S.: Pollution and the planetary albedo, Atmos. Environ., 8, 1251–1256, https://doi.org/10.1016/0004-6981(74)90004-3, 1974. a
Vautard, R., Yiou, P., and van Oldenborgh, G. J.: Decline of fog, mist and haze in Europe over the past 30 years, Nat. Geosci., 2, 115–119, https://doi.org/10.1038/ngeo414, 2009. a, b
von der Weiden, S.-L., Drewnick, F., and Borrmann, S.: Particle Loss Calculator – a new software tool for the assessment of the performance of aerosol inlet systems, Atmos.Meas. Tech., 2, 479–494, https://doi.org/10.5194/amt-2-479-2009, 2009. a
Wang, Q., Yamaguchi, R. T., Kalogiros, J. A., Daniels, Z., Alappattu, D. P., Jonsson, H., Alvarenga, O., Olson, A., Wauer, B. J., Ortiz-Suslow, D. G., and Fernando, H. J.: Microphysics and optical attenuation in fog: observations from two coastal sites, Bound.-Lay. Meteorol., 181, 267–292, https://doi.org/10.1007/s10546-021-00675-5, 2021a. a, b, c
Wang, Y., Niu, S., Lu, C., Lv, J., Zhang, J., Zhang, H., Zhang, S., Shao, N., Sun, W., Jin, Y., and Song, Q.: Observational study of the physical and chemical characteristics of the winter radiation fog in the tropical rainforest in Xishuangbanna, China, Sci. China Earth Sci., 64, 1982–1995, https://doi.org/10.1007/s11430-020-9766-4, 2021b. a, b
Weingartner, E., Nyeki, S., and Baltensperger, U.: Seasonal and diurnal variation of aerosol size distributions (
Wendisch, M., Mertes, S., Heintzenberg, J., Wiedensohler, A., Schell, D., Wobrock, W., Frank, G., Martinsson, B. G., Fuzzi, S., Orsi, G., Kos, G., and Berner, A.: Drop size distribution and LWC in Po Valley fog, Atmos. Phys., 71, 87–100, , 1998. a
WMO/GAW: WMO/GAW Aerosol Measurement Procedures, Guidelines and Recommendations, Report No. 227, 2nd Edn., World Meteorological Organization, Geneva, Switzerland, ISBN 978-92-63-11177-7, https://www.wmo-gaw-sag-aerosol.org/files/FINAL_GAW_227.pdf (last access 23 June 2026), 2016. a
Yan, S., Zhu, B., Huang, Y., Zhu, J., Kang, H., Lu, C., and Zhu, T.: To what extents do urbanization and air pollution affect fog?, Atmos. Chem. Phys., 20, 5559–5572, https://doi.org/10.5194/acp-20-5559-2020, 2020. a
Yan, S., Zhu, B., Zhu, T., Shi, C., Liu, D., Kang, H., Lu, W., and Lu, C.: The Effect of Aerosols on Fog Lifetime: Observational Evidence and Model Simulations, Geophys. Res. Lett., 48, e2020GL61803, https://doi.org/10.1029/2020GL091156, 2021. a
Zieger, P.: SU-air/publication-FAIRARI-Neuberger2026: Routines used in Neuberger et al. (2026) (Version Version_1.1), Zenodo [software], https://doi.org/10.5281/zenodo.21967941, 2026. a
Zieger, P., Fierz-Schmidhauser, R., Weingartner, E., and Baltensperger, U.: Effects of relative humidity on aerosol light scattering: results from different European sites, Atmos. Chem. Phys., 13, 10609–10631, https://doi.org/10.5194/acp-13-10609-2013, 2013. a
Zieger, P., Fierz-Schmidhauser, R., Poulain, L., Müller, T., Birmili, W., Spindler, G., Wiedensohler, A., Baltensperger, U., and Weingartner, E.: Influence of water uptake on the aerosol particle light scattering coefficients of the Central European aerosol, Tellus B, 66, 22716, https://doi.org/10.3402/tellusb.v66.22716, 2014. a
Short summary
We studied how particles from air pollution that absorb water but do not yet form fog droplets influence fog and visibility in northern Italy’s Po Valley. Using detailed field observations and computer modeling, we found that these “hydrated” particles can explain many low-visibility events. Recognizing their role helps improve forecasts of fog, air quality, and climate effects in polluted regions.
We studied how particles from air pollution that absorb water but do not yet form fog droplets...
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