Articles | Volume 26, issue 3
https://doi.org/10.5194/acp-26-2353-2026
© 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-26-2353-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
16 Feb 2026
Research article |
| 16 Feb 2026
| 16 Feb 2026
Aerosol iodine recycling is a major control on tropospheric reactive iodine abundance
Department of Atmospheric and Climate Science, University of Washington, Seattle, WA, United States
Leyang Liu
School of Energy and Environment, City University of Hong Kong, Hong Kong SAR, China
University of Hong Kong Shenzhen Research Institute, Shenzhen, China
Xuan Wang
School of Energy and Environment, City University of Hong Kong, Hong Kong SAR, China
University of Hong Kong Shenzhen Research Institute, Shenzhen, China
Yuk-Chun Chan
Department of Atmospheric and Climate Science, University of Washington, Seattle, WA, United States
Alyson Fritzmann
University of California Los Angeles Department of Atmospheric and Oceanic Sciences, Los Angeles, CA, United States
Ryan Pound
Wolfson Atmospheric Chemistry Laboratories, Department of Chemistry, University of York, York, UK
Amy Lees
Wolfson Atmospheric Chemistry Laboratories, Department of Chemistry, University of York, York, UK
Lewis Marden
Wolfson Atmospheric Chemistry Laboratories, Department of Chemistry, University of York, York, UK
Mat Evans
Wolfson Atmospheric Chemistry Laboratories, Department of Chemistry, University of York, York, UK
Lucy J. Carpenter
Wolfson Atmospheric Chemistry Laboratories, Department of Chemistry, University of York, York, UK
Jochen Stutz
University of California Los Angeles Department of Atmospheric and Oceanic Sciences, Los Angeles, CA, United States
Joel A. Thornton
Department of Atmospheric and Climate Science, University of Washington, Seattle, WA, United States
Gordon Novak
NOAA Chemical Sciences Laboratory, Boulder, CO, United States
Andrew Rollins
NOAA Chemical Sciences Laboratory, Boulder, CO, United States
Gregory P. Schill
NOAA Chemical Sciences Laboratory, Boulder, CO, United States
Xu-Cheng He
Institute for Atmospheric and Earth System Research/Physics, University of Helsinki, 00014 Helsinki, Finland
Henning Finkenzeller
Institute for Atmospheric and Earth System Research/Physics, University of Helsinki, 00014 Helsinki, Finland
Mago Reza
Department of Chemistry, University of Colorado Boulder, Boulder, CO, United States
Cooperative Institute for Research in Environmental Sciences (CIRES), University of Colorado Boulder, Boulder, CO, United States
Rainer Volkamer
Department of Chemistry, University of Colorado Boulder, Boulder, CO, United States
Cooperative Institute for Research in Environmental Sciences (CIRES), University of Colorado Boulder, Boulder, CO, United States
Kelvin H. Bates
Department of Mechanical Engineering, University of Colorado, Boulder, CO, United States
Alfonso Saiz-Lopez
Department of Atmospheric Chemistry and Climate, Institute of Physical Chemistry Blas Cabrera, CSIC, Madrid, Spain
Anoop S. Mahajan
Centre for Climate Change Research, Indian Institute of Tropical Meteorology, Pune, India
Department of Atmospheric and Climate Science, University of Washington, Seattle, WA, United States
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EGUsphere, https://doi.org/10.5194/egusphere-2026-4883, https://doi.org/10.5194/egusphere-2026-4883, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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Atmospheric methane levels have been rising in ways scientists struggle to explain. Much of the uncertainty lies in a chemical that removes methane from the air. Using a detailed model of the Earth, we found that chemistry plays an important role in the fate of methane in the atmosphere, even small variations need to be included to track methane accurately.
Sandhya Singh, Ashish Soni, Shivdas Bankar, Ritesh Kumar, Rohit Srivastava, Sreerag Athirpankandi, Rajani Kanta Mishra, Jitender Singh, Gaddamidi Sreenivas, Amey Datye, Yogesh Tiwari, Suvarna Fadnavis, Thara Prabhakaran, and Anoop Sharad Mahajan
EGUsphere, https://doi.org/10.5194/egusphere-2026-3546, https://doi.org/10.5194/egusphere-2026-3546, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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The Southern Ocean helps regulate Earth’s climate, but cloud formation in this region is poorly understood due to limited measurements. We collected the first continuous Cloud Condensation Nuclei (CCN) observations from the tropics to coastal Antarctica in the Indian Sector of the Southern Ocean. We show that sea spray was not the main source; however, CCN increased when air passed over biologically productive waters, showing marine life strongly influences cloud-forming particles.
Sneha Aggarwal, Matthew Salter, Olga Garmash, Felipe Lopez-Hilfiker, Julika Zinke, Joel A. Thornton, Timothy H. Bertram, Jian Wang, Paul Zieger, and Claudia Mohr
EGUsphere, https://doi.org/10.26434/chemrxiv.15000402/v3, https://doi.org/10.26434/chemrxiv.15000402/v3, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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Perfluoroalkyl carboxylic acids (PFCAs) are persistent global contaminants. While sea spray aerosol (SSA) formed by wave breaking is known to transport PFCAs from the ocean to the atmosphere, the focus has primarily been on particle-phase transport. Here, we present evidence that particle-bound PFCAs are subsequently converted to gas phase following SSA emission. This previously unconsidered process may cause particle-only measurements to underestimate the total atmospheric PFCA from SSA.
Samuel Ruhl, Matthias Kohl, Rima Baalbaki, Christos Xenofontos, Ryan Vella, Sergey Gromov, Xu-Cheng He, Jiali Shen, Dina Alfaouri, Samira Atabakhsh, Lubna Dada, Jenna DeVivo, Jonathan Duplissy, Imad El Haddad, Hartwig Harder, Tuija Jokinen, Heikki Junninen, Vijay P. Kanawade, Milin K. Sebastian, Hannah Klebach, Markku Kulmala, Felix Kunkler, Jos Lelieveld, Katrianne Lehtipalo, Clara J. Lietzke, Lu Liu, Roy Mauldin, Bernhard Mentler, Ottmar Möhler, Tuukka Petäjä, Douglas M. Russell, Mario Simon, Roseline C. Thakur, Wenjuan Yu, Jiangyi Zhang, Zhensen Zheng, Jasper Kirkby, Holger Tost, Theodoros Christoudias, Rolf Sander, and Andrea Pozzer
EGUsphere, https://doi.org/10.5194/egusphere-2026-4020, https://doi.org/10.5194/egusphere-2026-4020, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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Marine microbes release sulfur gases that form tiny particles able to seed clouds. Using a global chemistry-climate model, we compare four schemes for how these gases oxidise and test them against ship and ground measurements. We find that methanesulfonic acid can drive new particle formation as strongly as sulfuric acid over the cold Southern Ocean, supplying around 25 % of the cloud-forming particles there, a natural, climate-relevant source that models often overlook.
Yuwei Wang, Aristeidis Voliotis, Emily Matthews, Rongrong Wu, Milan Roska, Max Gerrit Adam, René Dubus, Lukas Kesper, Franz Rohrer, Robert Wegener, Benjamin Winter, Kelvin H. Bates, Quanfu He, Thorsten Hohaus, Achim Grasse, Ralf Tillmann, Andreas Wahner, Hui Wang, Christian Wesolek, Sergej Wedel, Yizhen Wu, Sören R. Zorn, Manjula Canagaratna, Douglas Worsnop, Felipe Lopez-Hilfiker, Georgios I. Gkatzelis, Hugh Coe, and Thomas J. Bannan
Atmos. Meas. Tech., 19, 4583–4599, https://doi.org/10.5194/amt-19-4583-2026, https://doi.org/10.5194/amt-19-4583-2026, 2026
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This work developed voltage scanning based calibration approach for a multi-reagent chemical ionization mass spectrometry. This approach improves sensitivity determination for gas-phase compounds. It does not require a calibrant for the target analyte and can estimate sensitivity with acceptable uncertainty based on the experimentally established relationship between binding energies and measured sensitivities. This work is broadly relevant to mass-spectrometric calibration strategies.
Matthias Kohl, Christoph Brühl, Holger Tost, Christos Xenofontos, Theodoros Christoudias, Sergey Gromov, Oliver Appel, Stephan Borrmann, Adam Bourassa, Pedro Campunzano-Jost, Yafang Cheng, Oliver Eppers, Karl D. Froyd, Bruna A. Holanda, Jose L. Jimenez, Patrick Jöckel, Philipp Joppe, Katharina Kaiser, Joseph M. Katich, Klaus Klingmüller, Franziska Köllner, Agnieszka Kupc, Anna Martin, Christopher Pöhlker, Mira L. Pöhlker, Ulrich Pöschl, Landon Rieger, Samuel Ruhl, Gregory P. Schill, Johannes Schneider, Christiane Schulz, Joshua P. Schwarz, Alexandra P. Tsimpidi, Ryan Vella, Christina J. Williamson, Yifan Yang, Daniel Zawada, Jos Lelieveld, and Andrea Pozzer
EGUsphere, https://doi.org/10.5194/egusphere-2026-3649, https://doi.org/10.5194/egusphere-2026-3649, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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Aerosols are crucial for Earth's climate, yet their vertical distribution remains poorly understood. We present first consistent global simulations of aerosol distributions and composition from the Earth's surface to the stratosphere, validated by extensive observations. Key findings include a global minimum in aerosol mass in the free troposphere, a significant contribution of organic aerosol in the lower stratosphere, and limited transport of primary particles to the stratosphere.
Farhan R. Nursanto, Quanfu He, Sophia van de Wouw, Annika Zanders, Thorsten Hohaus, Willem S. J. Kroese, Robert Wegener, Max Gerrit Adam, Benjamin Winter, René Dubus, Lukas Kesper, Franz Rohrer, Yuwei Wang, Emily Matthews, Aristeidis Voliotis, Thomas J. Bannan, Gordon McFiggans, Hugh Coe, Yizhen Wu, Milan Roska, Manjula Canagaratna, Mitch Alton, Matthew M. Coggon, Chelsea E. Stockwell, Kelvin H. Bates, Eva Y. Pfannerstill, Sören R. Zorn, Hui Wang, Matthieu Riva, Sebastien Perrier, Boxing Yang, Lu Liu, Anna Novelli, Michelle Färber, Hendrik Fuchs, Andrea Carolina Marcillo Lara, Achim Grasse, Christian Wesolek, Ralf Tillmann, Rupert Holzinger, Maarten C. Krol, Georgios I. Gkatzelis, and Juliane L. Fry
Atmos. Chem. Phys., 26, 8425–8453, https://doi.org/10.5194/acp-26-8425-2026, https://doi.org/10.5194/acp-26-8425-2026, 2026
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Urban air contains reactive gases that can form organic nitrate particles and carry nitrogen oxides pollution far from cities. We recreated urban emissions in a large atmospheric chamber and observed their reactions under day and night conditions. We found that these emissions form organic nitrate particles similar to those from natural sources, with higher amounts and heavier particles at night, making nitrogen pollution longer lived and likely to travel further before depositing on ecosystems.
Han Ding, Pratapaditya Ghosh, Xu-Cheng He, R. Lee Mauldin III, David O'Neal, John Ortega, James Norman Smith, and Hamish Gordon
EGUsphere, https://doi.org/10.5194/egusphere-2026-932, https://doi.org/10.5194/egusphere-2026-932, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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About half of the particles in the atmosphere that affect the properties of clouds are formed when gas molecules cluster together. This clustering process is usually very simplified in atmospheric models. Here we test a more sophisticated clustering mechanism in a regional setup of a climate model, using aircraft measurements in Colorado. Including ammonia in the mechanism can substantially improve predictions of atmospheric particle concentrations, but other species probably contribute as well.
Austin D. Dobrecevich, Felipe Lopez-Hilfiker, Chris J. Wright, Urs Rohner, and Joel A. Thornton
Atmos. Meas. Tech., 19, 3481–3490, https://doi.org/10.5194/amt-19-3481-2026, https://doi.org/10.5194/amt-19-3481-2026, 2026
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A portable mass spectrometer has been developed to sensitively measure key environmental pollutants at high temporal resolution. Its low power consumption and compact design enable battery-powered operation and deployment in challenging settings such as light aircraft, tall towers, and remote, off-grid locations, providing new insight into atmospheric chemical variability with high spatial and temporal accuracy.
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
Atmos. Meas. Tech., 19, 3363–3396, https://doi.org/10.5194/amt-19-3363-2026, https://doi.org/10.5194/amt-19-3363-2026, 2026
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We describe accurate measurement of particle formation and growth in the CERN CLOUD (European Council for Nuclear Research Cosmics Leaving OUtdoor Droplets) 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.
Tea Thum, Javier Pacheco-Labrador, Mika Aurela, Alan Barr, Marika Honkanen, Bruce Johnson, Hannakaisa Lindqvist, Troy Magney, Mirco Migliavacca, Zoe Amie Pierrat, Tristan Quaife, Jochen Stutz, and Sönke Zaehle
Biogeosciences, 23, 3541–3565, https://doi.org/10.5194/bg-23-3541-2026, https://doi.org/10.5194/bg-23-3541-2026, 2026
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Solar-induced chlorophyll fluorescence (SIF) is an optical signal emitted by plants, connected to the biochemical status of the plants. Therefore it helps to unveil what happens inside plants and since it can be observed with remote sensing, it provides a global view of plant activity. We included SIF module in a terrestrial biosphere model and examined how to best describe movement of the SIF signal in the forest. Our work will help to model SIF in boreal coniferous forests.
Xinyue Shao, Yaman Liu, Xinyi Dong, Minghuai Wang, Ruochong Xu, Joel A. Thornton, Duseong S. Jo, Man Yue, Wenxiang Shen, Manish Shrivastava, Stephen R. Arnold, and Ken S. Carslaw
Atmos. Chem. Phys., 26, 6427–6448, https://doi.org/10.5194/acp-26-6427-2026, https://doi.org/10.5194/acp-26-6427-2026, 2026
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Highly Oxygenated Organic Molecules (HOMs) are key precursors of secondary organic aerosols (SOA). Incorporating the HOMs chemical mechanism into a global climate model allows for a reasonable reproduction of observed HOM characteristics. HOM-SOA constitutes a significant fraction of global SOA, and its distribution and formation pathways exhibit strong sensitivity to uncertainties in autoxidation processes and peroxy radical branching ratios.
Lewis Marden, Marvin D. Shaw, Stephen J. Andrews, Maya Zmajkovic, Phil Rund, Becky Alexander, Joel Thornton, Andrew Peters, Peter Karadakov, and Lucy J. Carpenter
Atmos. Meas. Tech., 19, 2715–2735, https://doi.org/10.5194/amt-19-2715-2026, https://doi.org/10.5194/amt-19-2715-2026, 2026
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Hypoiodous acid (HOI) and molecular iodine (I2) are the dominant precursors of reactive gaseous iodine, which plays an important role in the atmospheric oxidative capacity and in aerosol formation. However, difficulties in the quantification of HOI and I2 mean that very few measurements are available. This work describes a novel calibration method for HOI and reports the detection of HOI and I2 in the marine boundary layer using Br- chemical ionisation mass spectrometry.
Aoxing Zhang, Tzung-May Fu, Yuhang Wang, Enyu Xiong, Wenlu Wu, Yumin Li, Lei Zhu, Wei Tao, Kelley C. Wells, Dylan B. Millet, Zhe Wang, Bin Yuan, Min Shao, Christophe Lerot, Thomas Danckaert, Ruixiong Zhang, and Kelvin H. Bates
Atmos. Chem. Phys., 26, 5123–5150, https://doi.org/10.5194/acp-26-5123-2026, https://doi.org/10.5194/acp-26-5123-2026, 2026
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Glyoxal, a product of volatile organic compound oxidation, influences atmospheric oxidation and aerosol formation but is underestimated in models. By improving emissions, chemistry, and marine sources in GEOS-Chem, we better reproduce observed glyoxal over land and ocean, which strengthens global oxidation capacity and aerosol formation. The results highlight glyoxal's role as a proxy of atmospheric oxidation, and emphasize the needs of accurately representing glyoxal chemistry.
Andre F. Schaum, Christopher M. Kenseth, Madison Rutherford, Harald Stark, Manjula R. Canagaratna, Joost A. de Gouw, Jose L. Jimenez, and Kelvin H. Bates
Aerosol Research Discuss., https://doi.org/10.5194/ar-2026-13, https://doi.org/10.5194/ar-2026-13, 2026
Revised manuscript has not been submitted
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Organic aerosols influence global climate though uncertainties in the magnitude of this influence remain large. A comprehensive understanding of the molecular composition of aerosols is key to minimizing these uncertainties. We present a new method for analyzing organic aerosols in real time using ion mobility mass spectrometry, enabling the separation of aerosol components with identical mass. Analysis of standards and laboratory-generated aerosols demonstrate the method’s potential.
Da Yang, Emmanuel Assaf, Roy Mauldin, Suresh Dhaniyala, and Rainer Volkamer
Atmos. Meas. Tech., 19, 2329–2342, https://doi.org/10.5194/amt-19-2329-2026, https://doi.org/10.5194/amt-19-2329-2026, 2026
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Sulfuric acid forms particles in the atmosphere, but the airborne sampling faces challenges due to vapor losses in inlet lines. An innovative aircraft sampling system to sample sulfuric acid from the sea surface into the lower stratosphere (0–15 km) is described and characterized. Our results challenge the widely held view that laminar core sampling is the best strategy to sample condensable vapors, and identify better strategies to sample condensable vapors.
James Young Suk Yoon, Kelley C. Wells, Dylan B. Millet, Christian Frankenberg, Suniti Sanghavi, Abigail L. S. Swann, Joel A. Thornton, and Alexander J. Turner
Atmos. Chem. Phys., 26, 4509–4529, https://doi.org/10.5194/acp-26-4509-2026, https://doi.org/10.5194/acp-26-4509-2026, 2026
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Isoprene is a molecule emitted by trees that is oxidized in the atmosphere within hours. Much of the isoprene globally is emitted in the remote tropics, where we have few direct observations of isoprene. Here, we use new satellite retrievals of isoprene to infer drivers of tropical isoprene variability. Across three regions, isoprene column variability is controlled by different factors, namely changes in isoprene emissions or changes in natural nitrogen oxide sources, like soils and fires.
Jochen Stutz, Jonas Kuhn, Sol Cooperdock, Sarah Johnson, Fangzhou Guo, James H. Flynn, Meeta Cesler-Maloney, and William R. Simpson
EGUsphere, https://doi.org/10.5194/egusphere-2026-816, https://doi.org/10.5194/egusphere-2026-816, 2026
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Northern cities often experience periods of wintertime air pollution, which are associated with surface temperature inversions and weak winds. In Fairbanks, Alaska, pollutants accumulate in a 20–40 m high surface layer with SO2 and NO2 mixing ratios of up to 35 ppb and 65 ppb, respectively. This surface pollution is caused by the balance of emissions, chemistry, and inefficient mixing with clean background air. This balance has to be considered for air pollution mitigation strategies.
Xu-Cheng He, Nathan Luke Abraham, Han Ding, Maria R. Russo, Daniel P. Grosvenor, Yao Ge, Xuemei Wang, Anthony C. Jones, Pedro Campuzano-Jost, Benjamin Nault, Agnieszka Kupc, Donald Blake, Jose L. Jimenez, Christina J. Williamson, James Weber, Alexander T. Archibald, and Hamish Gordon
Atmos. Chem. Phys., 26, 3805–3851, https://doi.org/10.5194/acp-26-3805-2026, https://doi.org/10.5194/acp-26-3805-2026, 2026
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Aerosols affect clouds and climate. However, current climate models still struggle to simulate them accurately. We used aircraft data from a global mission to evaluate how well the UK Earth System Model represents aerosols and their precursors. Our results show that the model misses key formation processes in clean ocean regions, suggesting that future improvements should focus on better representing how aerosols form naturally in the atmosphere.
Ruize Sun, Xiao Lu, Haipeng Lin, Tongwen Wu, Xingpei Ye, Lu Shen, Xuan Wang, Haolin Wang, Jingyu Li, Ni Lu, Jiayin Su, Jie Zhang, Fang Zhang, Xiaoge Xin, Xiong Liu, Xiao Yang, and Lin Zhang
Geosci. Model Dev., 19, 2111–2136, https://doi.org/10.5194/gmd-19-2111-2026, https://doi.org/10.5194/gmd-19-2111-2026, 2026
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We present the development of a global chemistry-climate coupled model BCC-GEOS-Chem v2.0, with improved representation of comprehensive troposphere-stratosphere chemistry and new capability to account for radiative-cloud feedbacks from short-lived climate forcers. The development of the BCC-GEOS-Chem v2.0 provides a useful framework for investigating climate–chemistry interactions and for future projections of global atmospheric chemistry
Nadia K. Colombi, Daniel J. Jacob, Xingpei Ye, Robert M. Yantosca, Kelvin H. Bates, Drew C. Pendergrass, Laura Hyesung Yang, Ke Li, and Hong Liao
Atmos. Chem. Phys., 26, 2623–2633, https://doi.org/10.5194/acp-26-2623-2026, https://doi.org/10.5194/acp-26-2623-2026, 2026
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Surface ozone pollution in East Asia is among the highest in the world and has risen steadily over the past two decades. Using aircraft observations and a global 3-D chemical transport model, we show that ozone in the lower atmosphere in East Asia has risen in part due to intensified transport from the upper atmosphere. This rising natural background limits the effectiveness of local pollution controls, with major implications for air quality policy.
Loren G. Temple, Stuart Young, Thomas Bannan, Stephanie E. Batten, Stéphane Bauguitte, Hugh Coe, Eve Grant, Stuart E. Lacy, James D. Lee, Emily Matthews, Dominika Pasternak, Samuel D. A. Rogers, Andrew W. Rollins, Jake Vallow, Mingxi Yang, and Pete M. Edwards
Atmos. Meas. Tech., 19, 1165–1178, https://doi.org/10.5194/amt-19-1165-2026, https://doi.org/10.5194/amt-19-1165-2026, 2026
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Sulfur dioxide (SO2) is a key precursor to aerosol formation, particularly in remote marine environments, ultimately affecting cloud properties and climate. Accurate quantification of atmospheric SO2 is therefore crucial. This work compares a custom-built laser-based instrument to two commercial SO2 analysers during measurements from a large research aircraft. Our results show that this custom-built system offers greater sensitivity at time resolutions required for aircraft measurements.
Jan-Lukas Tirpitz, Nathaniel Brockway, Santo Fedele Colosimo, Robert Spurr, Matt Christi, Samuel Hall, Kirk Ullmann, Vijay Natraj, Nicolas Theys, Johnathan Hair, Taylor Shingler, Rodney Weber, Ruchen Zhu, Jack Dibb, Richard Moore, Elizabeth Wiggins, and Jochen Stutz
EGUsphere, https://doi.org/10.5194/egusphere-2025-5541, https://doi.org/10.5194/egusphere-2025-5541, 2026
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This study applies a novel remote sensing algorithm to airborne radiation measurements performed in wildfire plumes, to retrieve the absorptive properties of biomass burning aerosols. The results provide new insights on the magnitude, wavelength dependence, and atmospheric aging of the imaginary refractive index, volume absorption cross-section, and single scattering albedo of the smoke particles. Furthermore, potential and limitations of the applied method are discussed.
Joseph O. Palmo, Colette L. Heald, Donald R. Blake, Ilann Bourgeois, Matthew Coggon, Jeff Collett, Frank Flocke, Alan Fried, Georgios Gkatzelis, Samuel Hall, Lu Hu, Jose L. Jimenez, Pedro Campuzano-Jost, I-Ting Ku, Benjamin Nault, Brett Palm, Jeff Peischl, Ilana Pollack, Amy Sullivan, Joel Thornton, Carsten Warneke, Armin Wisthaler, and Lu Xu
Atmos. Chem. Phys., 25, 17107–17124, https://doi.org/10.5194/acp-25-17107-2025, https://doi.org/10.5194/acp-25-17107-2025, 2025
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This study investigates ozone production within wildfire smoke plumes as they age, using both aircraft observations and models. We find that the chemical environment and resulting ozone production within smoke changes as plumes evolve, with implications for climate and public health.
Alfred W. Mayhew, Lauri Franzon, Kelvin H. Bates, Theo Kurtén, Felipe D. Lopez-Hilfiker, Claudia Mohr, Andrew R. Rickard, Joel A. Thornton, and Jessica D. Haskins
Atmos. Chem. Phys., 25, 17027–17046, https://doi.org/10.5194/acp-25-17027-2025, https://doi.org/10.5194/acp-25-17027-2025, 2025
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This work outlines an investigation into an understudied atmospheric chemical reaction pathway with the potential to form particulate pollution that has important impacts on air quality and climate. It suggests that this chemical pathway is responsible for a large fraction of the atmospheric particulate matter observed in tropical forested regions, but also highlights the need for further ambient and lab investigations to inform an accurate representation of this process in atmospheric models.
Andre F. Schaum, Kelvin H. Bates, Kyung-Eun Min, Faith Myers, Emmaline R. Longnecker, Manjula R. Canagaratna, Mitchell W. Alton, and Paul J. Ziemann
Aerosol Research, 3, 557–568, https://doi.org/10.5194/ar-3-557-2025, https://doi.org/10.5194/ar-3-557-2025, 2025
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Organic aerosols consist of complex chemical mixtures that are challenging to characterize using chemical ionization mass spectrometry alone. This study presents a method for coupling liquid chromatography and chemical ionization mass spectrometry for the offline analysis of organic aerosols. The evaluation of the method using standards and laboratory-generated and field-collected organic aerosols showed that it can provide detailed characterization of environmentally relevant mixtures.
Matthew J. Rowlinson, Lucy J. Carpenter, Mat J. Evans, James D. Lee, Simone T. Andersen, Tomas Sherwen, Anna B. Callaghan, Roberto Sommariva, William Bloss, Siqi Hou, Leigh R. Crilley, Klaus Pfeilsticker, Benjamin Weyland, Thomas B. Ryerson, Patrick R. Veres, Pedro Campuzano-Jost, Hongyu Guo, Benjamin A. Nault, Jose L. Jimenez, and Khanneh Wadinga Fomba
Atmos. Chem. Phys., 25, 16945–16968, https://doi.org/10.5194/acp-25-16945-2025, https://doi.org/10.5194/acp-25-16945-2025, 2025
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HONO is key to tropospheric chemistry. Observations show high HONO concentrations in remote air, possibly explained by nitrate aerosol photolysis. We use observations to parameterize nitrate photolysis, evaluating simulated HONO against observations from multiple sources. We show improved agreement with observed HONO, but overestimates in NOx and O3, beyond observational constraints. This implies uncertainties in the NOx budget and our understanding of atmospheric chemistry.
Phil Rund, Ben H. Lee, Siddharth Iyer, Gordon A. Novak, Jake T. Vallow, and Joel A. Thornton
Atmos. Meas. Tech., 18, 6979–6995, https://doi.org/10.5194/amt-18-6979-2025, https://doi.org/10.5194/amt-18-6979-2025, 2025
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We introduce a custom-built chamber (known as an IMR) for use with a Chemical Ionization Mass Spectrometry (CIMS) gas measurement instrument. The IMR shows large improvements compared to previous designs in reducing non-real signal in the instrument, reducing uncertainties for trace gas studies in the laboratory and the field. We characterize this new IMR and demonstrate its use in analyzing air masses of unknown composition during a field campaign, reporting concentrations of important gases.
Tyler R. Elgiar, Loknath Dhar, Lynne Gratz, A. Gannet Hallar, Rainer Volkamer, and Seth N. Lyman
Atmos. Chem. Phys., 25, 16387–16399, https://doi.org/10.5194/acp-25-16387-2025, https://doi.org/10.5194/acp-25-16387-2025, 2025
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We compare verified atmospheric mercury measurements against output from the GEOS-Chem photochemical transport model. We show the model is unable to reproduce measured atmospheric oxidized mercury concentrations, even in several cases where oxidation rates in the model are enhanced.
Abby Sebol, Glenn Wolfe, Timothy Canty, Jason St. Clair, Erin Delaria, Jennifer Kaiser, Nidhi Desai, Andrew Rollins, Eleanor Waxman, Kristen Zuraski, Bryan Place, Apoorva Pandey, Akanksha Singh, Allison Ring, Charles Gatebe, and Jonathan Dean-Day
EGUsphere, https://doi.org/10.5194/egusphere-2025-5261, https://doi.org/10.5194/egusphere-2025-5261, 2025
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Ground-based spectrometers measuring HCHO and NO2 were compared to airborne in situ observations in the Summer 2023. Total column HCHO is within uncertainty, but with high biases near the surface. NO2 results are highly sensitive to the viewing angle of the ground monitor which must be considered during validation studies. Spectrometers in NYC show good agreement with a geostationary satellite on clear-sky days. Further quantified uncertainty for the monitors is necessary.
Xinchun Xie, Yuzhong Zhang, Ruosi Liang, and Xuan Wang
Atmos. Chem. Phys., 25, 13547–13561, https://doi.org/10.5194/acp-25-13547-2025, https://doi.org/10.5194/acp-25-13547-2025, 2025
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Brown carbon (BrC), mainly from biomass burning, absorbs short-wavelength sunlight and affects climate and atmospheric chemistry. This study implemented an improved parameterization of BrC bleaching in a model with which BrC can survive much longer in cold, dry air, especially when lofted into the upper atmosphere by wildfires. The results reveal stronger warming effects and impacts on atmospheric oxidation, highlighting the need to consider BrC in climate and pollution control strategies.
Rafael Pedro Fernandez, Carlos Alberto Cuevas, Julián Villamayor, Aryeh Feinberg, Douglas E. Kinnison, Francis Vitt, Adriana Bossolasco, Javier A. Barrera, Amelia Reynoso, Orlando G. Tomazzeli, Qinyi Li, and Alfonso Saiz-Lopez
EGUsphere, https://doi.org/10.5194/egusphere-2025-3250, https://doi.org/10.5194/egusphere-2025-3250, 2025
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In this work we summarize 15 years of research and developments of short-lived halogens (SLH) using the Community Earth System Model (CESM) and present a complete description of the implementation and capabilities achieved with the new released version CESM2-SLH, including specific namelist options, input files and technical notes detailing the most important SLH updates that must be considered for the different model configurations and resolutions.
Yugo Kanaya, Roberto Sommariva, Alfonso Saiz-Lopez, Andrea Mazzeo, Theodore K. Koenig, Kaori Kawana, James E. Johnson, Aurélie Colomb, Pierre Tulet, Suzie Molloy, Ian E. Galbally, Rainer Volkamer, Anoop Mahajan, John W. Halfacre, Paul B. Shepson, Julia Schmale, Hélène Angot, Byron Blomquist, Matthew D. Shupe, Detlev Helmig, Junsu Gil, Meehye Lee, Sean C. Coburn, Ivan Ortega, Gao Chen, James Lee, Kenneth C. Aikin, David D. Parrish, John S. Holloway, Thomas B. Ryerson, Ilana B. Pollack, Eric J. Williams, Brian M. Lerner, Andrew J. Weinheimer, Teresa Campos, Frank M. Flocke, J. Ryan Spackman, Ilann Bourgeois, Jeff Peischl, Chelsea R. Thompson, Ralf M. Staebler, Amir A. Aliabadi, Wanmin Gong, Roeland Van Malderen, Anne M. Thompson, Ryan M. Stauffer, Debra E. Kollonige, Juan Carlos Gómez Martin, Masatomo Fujiwara, Katie Read, Matthew Rowlinson, Keiichi Sato, Junichi Kurokawa, Yoko Iwamoto, Fumikazu Taketani, Hisahiro Takashima, Mónica Navarro-Comas, Marios Panagi, and Martin G. Schultz
Earth Syst. Sci. Data, 17, 4901–4932, https://doi.org/10.5194/essd-17-4901-2025, https://doi.org/10.5194/essd-17-4901-2025, 2025
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The first comprehensive dataset of tropospheric ozone over oceans/polar regions is presented, including 77 ship/buoy and 48 aircraft campaign observations (1977–2022, 0–5000 m altitude), supplemented by ozonesonde and surface data. Air masses isolated from land for 72+ hours are systematically selected as essentially oceanic. Among the 11 global regions, they show daytime decreases of 11–16 % in the tropics, while near-zero depletions are rare, unlike in the Arctic, implying different mechanisms.
Laura M. D. Heinlein, Junwei He, Michael Oluwatoyin Sunday, Fangzhou Guo, James Campbell, Allison Moon, Sukriti Kapur, Ting Fang, Kasey Edwards, Meeta Cesler-Maloney, Alyssa J. Burns, Jack Dibb, William Simpson, Manabu Shiraiwa, Becky Alexander, Jingqiu Mao, James H. Flynn III, Jochen Stutz, and Cort Anastasio
Atmos. Chem. Phys., 25, 9561–9581, https://doi.org/10.5194/acp-25-9561-2025, https://doi.org/10.5194/acp-25-9561-2025, 2025
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High-latitude cities like Fairbanks, Alaska, experience severe wintertime pollution episodes. While conventional wisdom holds that oxidation is slow under these conditions, field measurements find oxidized products in particles. To explore this, we measured oxidants in aqueous extracts of winter particles from Fairbanks. We find high concentrations of oxidants during illumination experiments, indicating that particle photochemistry can be significant even in high latitudes during winter.
John W. Halfacre, Lewis Marden, Marvin D. Shaw, Lucy J. Carpenter, Emily Matthews, Thomas J. Bannan, Hugh Coe, Scott C. Herndon, Joseph R. Roscioli, Christoph Dyroff, Tara I. Yacovitch, Patrick R. Veres, Michael A. Robinson, Steven S. Brown, and Pete M. Edwards
Atmos. Meas. Tech., 18, 3799–3818, https://doi.org/10.5194/amt-18-3799-2025, https://doi.org/10.5194/amt-18-3799-2025, 2025
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Nitryl chloride (ClNO2) is a reservoir of chlorine atoms and nitrogen oxides, both of which play important roles in atmospheric chemistry. However, all ambient ClNO2 observations so far have been made by a single technique, mass spectrometry, which needs complex calibrations. Here, we present a laser-based method that detects ClNO2 (TD-TILDAS – thermal dissociation–tunable infrared laser direct absorption spectrometry) without the need for complicated calibrations. The results show excellent agreement between these two methods from both laboratory and ambient samples.
Carley D. Fredrickson, Scott J. Janz, Lok N. Lamsal, Ursula A. Jongebloed, Joshua L. Laughner, and Joel A. Thornton
Atmos. Meas. Tech., 18, 3669–3689, https://doi.org/10.5194/amt-18-3669-2025, https://doi.org/10.5194/amt-18-3669-2025, 2025
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We present an analysis of high-resolution remote sensing measurements of nitrogen-containing trace gases emitted by wildfires. The measurements were made using an instrument on the NASA ER-2 aircraft in the summer of 2019. We find that time-resolved fire intensity is critical to quantify trace gas emissions over a fire's entire lifespan. These findings have implications for improving air pollution forecasts downwind of wildfires using computer models of atmospheric chemistry and meteorology.
Wanmin Gong, Stephen R. Beagley, Kenjiro Toyota, Henrik Skov, Jesper Heile Christensen, Alex Lupu, Diane Pendlebury, Junhua Zhang, Ulas Im, Yugo Kanaya, Alfonso Saiz-Lopez, Roberto Sommariva, Peter Effertz, John W. Halfacre, Nis Jepsen, Rigel Kivi, Theodore K. Koenig, Katrin Müller, Claus Nordstrøm, Irina Petropavlovskikh, Paul B. Shepson, William R. Simpson, Sverre Solberg, Ralf M. Staebler, David W. Tarasick, Roeland Van Malderen, and Mika Vestenius
Atmos. Chem. Phys., 25, 8355–8405, https://doi.org/10.5194/acp-25-8355-2025, https://doi.org/10.5194/acp-25-8355-2025, 2025
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This study showed that the springtime O3 depletion plays a critical role in driving the surface O3 seasonal cycle in the central Arctic. The O3 depletion events, while occurring most notably within the lowest few hundred metres above the Arctic Ocean, can induce a 5–7 % loss in the pan-Arctic tropospheric O3 burden during springtime. The study also found enhancements in O3 and NOy (mostly peroxyacetyl nitrate) concentrations in the Arctic due to northern boreal wildfires, particularly at higher altitudes.
Jasna V. Pittman, Bruce C. Daube, Steven C. Wofsy, Elliot L. Atlas, Maria A. Navarro, Eric J. Hintsa, Fred L. Moore, Geoff S. Dutton, James W. Elkins, Troy D. Thornberry, Andrew W. Rollins, Eric J. Jensen, Thaopaul Bui, Jonathan Dean-Day, and Leonhard Pfister
Atmos. Chem. Phys., 25, 7543–7562, https://doi.org/10.5194/acp-25-7543-2025, https://doi.org/10.5194/acp-25-7543-2025, 2025
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Biomass fires emit aerosols and precursors that can provide a novel environment for initiating stratospheric ozone loss. The Airborne Tropical TRopopause EXperiment campaign sampled the western Pacific, the dominant longitudes for surface air lofted by convection to enter the global stratosphere. Aircraft measurements over multiple flights revealed persistent layers of biomass burning pollutants entering the lower stratosphere and originating from fires as far away as Africa and Indonesia.
Dongwook Kim, Pedro Campuzano-Jost, Hongyu Guo, Douglas A. Day, Da Yang, Suresh Dhaniyala, Leah Williams, Philip Croteau, John Jayne, Douglas Worsnop, Rainer Volkamer, and Jose L. Jimenez
Aerosol Research, 3, 371–404, https://doi.org/10.5194/ar-3-371-2025, https://doi.org/10.5194/ar-3-371-2025, 2025
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Quantitative real-time aerosol sampling on board aircraft platforms is challenging, especially at higher altitudes. Herein, we present comprehensive analyses of a new aircraft inlet system and tools for aerosol beam diagnostics for aerosol mass spectrometers (AMSs). The beam focusing of aerodynamic lenses and the thermal decomposition on the vaporizer were investigated. The new inlet system can be operated at higher altitudes while sampling aerosols over a broader size range than previous versions.
Juan A. Añel, Juan-Carlos Antuña-Marrero, Antonio Cid Samamed, Celia Pérez-Souto, Laura de la Torre, Maria Antonia Valente, Yuri Brugnara, Alfonso Saiz-Lopez, and Luis Gimeno
Earth Syst. Sci. Data, 17, 2437–2446, https://doi.org/10.5194/essd-17-2437-2025, https://doi.org/10.5194/essd-17-2437-2025, 2025
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Ozone (discovered in 1837) was first measured in 1847 using paper strips that reacted with ozone, providing an indication of its concentration based on colour changes. Here, we present the data, covering over 60 years of daily observations conducted along the eastern Atlantic coast, spanning from the tropics to the northern extratropics.
Michael Oluwatoyin Sunday, Laura Marie Dahler Heinlein, Junwei He, Allison Moon, Sukriti Kapur, Ting Fang, Kasey C. Edwards, Fangzhou Guo, Jack Dibb, James H. Flynn III, Becky Alexander, Manabu Shiraiwa, and Cort Anastasio
Atmos. Chem. Phys., 25, 5087–5100, https://doi.org/10.5194/acp-25-5087-2025, https://doi.org/10.5194/acp-25-5087-2025, 2025
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Hydrogen peroxide (HOOH) is an important oxidant that forms atmospheric sulfate. We demonstrate that the illumination of brown carbon can rapidly form HOOH within particles, even under the low-sunlight conditions of Fairbanks, Alaska, during winter. This in-particle formation of HOOH is fast enough that it forms sulfate at significant rates. In contrast, the formation of HOOH in the gas phase during the campaign is expected to be negligible because of high NOx levels.
Ursula A. Jongebloed, Jacob I. Chalif, Linia Tashmim, William C. Porter, Kelvin H. Bates, Qianjie Chen, Erich C. Osterberg, Bess G. Koffman, Jihong Cole-Dai, Dominic A. Winski, David G. Ferris, Karl J. Kreutz, Cameron P. Wake, and Becky Alexander
Atmos. Chem. Phys., 25, 4083–4106, https://doi.org/10.5194/acp-25-4083-2025, https://doi.org/10.5194/acp-25-4083-2025, 2025
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Marine phytoplankton emit dimethyl sulfide (DMS), which forms methanesulfonic acid (MSA) and sulfate. MSA concentrations in ice cores decreased over the industrial era, which has been attributed to pollution-driven changes in DMS chemistry. We use a model to investigate DMS chemistry compared to observations of DMS, MSA, and sulfate. We find that modeled DMS, MSA, and sulfate are influenced by pollution-sensitive oxidant concentrations, characterization of DMS chemistry, and other variables.
Chris J. Wright, Joel A. Thornton, Lyatt Jaeglé, Yang Cao, Yannian Zhu, Jihu Liu, Randall Jones II, Robert Holzworth, Daniel Rosenfeld, Robert Wood, Peter Blossey, and Daehyun Kim
Atmos. Chem. Phys., 25, 2937–2946, https://doi.org/10.5194/acp-25-2937-2025, https://doi.org/10.5194/acp-25-2937-2025, 2025
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Aerosol particles influence clouds, which exert a large forcing on solar radiation and freshwater. To better understand the mechanisms by which aerosol influences thunderstorms, we look at the two busiest shipping lanes in the world, where recent regulations have reduced sulfur emissions by nearly an order of magnitude. We find that the reduction in emissions has been accompanied by a dramatic decrease in both lightning and the number of droplets in clouds over the shipping lanes.
Hendrik Fuchs, Aaron Stainsby, Florian Berg, René Dubus, Michelle Färber, Andreas Hofzumahaus, Frank Holland, Kelvin H. Bates, Steven S. Brown, Matthew M. Coggon, Glenn S. Diskin, Georgios I. Gkatzelis, Christopher M. Jernigan, Jeff Peischl, Michael A. Robinson, Andrew W. Rollins, Nell B. Schafer, Rebecca H. Schwantes, Chelsea E. Stockwell, Patrick R. Veres, Carsten Warneke, Eleanor M. Waxman, Lu Xu, Kristen Zuraski, Andreas Wahner, and Anna Novelli
Atmos. Meas. Tech., 18, 881–895, https://doi.org/10.5194/amt-18-881-2025, https://doi.org/10.5194/amt-18-881-2025, 2025
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Significant improvements have been made to the instruments used to measure OH reactivity, which is equivalent to the sum of air pollutant concentrations. Accurate and precise measurements with a high time resolution have been achieved, allowing use on aircraft, as demonstrated during flights in the USA.
Jan-Lukas Tirpitz, Santo Fedele Colosimo, Nathaniel Brockway, Robert Spurr, Matt Christi, Samuel Hall, Kirk Ullmann, Johnathan Hair, Taylor Shingler, Rodney Weber, Jack Dibb, Richard Moore, Elizabeth Wiggins, Vijay Natraj, Nicolas Theys, and Jochen Stutz
Atmos. Chem. Phys., 25, 1989–2015, https://doi.org/10.5194/acp-25-1989-2025, https://doi.org/10.5194/acp-25-1989-2025, 2025
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We combine plume composition data from the 2019 NASA FIREX-AQ campaign with state-of-the-art radiative transfer modeling techniques to calculate distributions of actinic flux and photolysis frequencies in a wildfire plume. Excellent agreement of the model and observations demonstrates the applicability of this approach to constrain photochemistry in such plumes. We identify limiting factors for the modeling accuracy and discuss spatial and spectral features of the distributions.
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.
Chelsea E. Stockwell, Matthew M. Coggon, Rebecca H. Schwantes, Colin Harkins, Bert Verreyken, Congmeng Lyu, Qindan Zhu, Lu Xu, Jessica B. Gilman, Aaron Lamplugh, Jeff Peischl, Michael A. Robinson, Patrick R. Veres, Meng Li, Andrew W. Rollins, Kristen Zuraski, Sunil Baidar, Shang Liu, Toshihiro Kuwayama, Steven S. Brown, Brian C. McDonald, and Carsten Warneke
Atmos. Chem. Phys., 25, 1121–1143, https://doi.org/10.5194/acp-25-1121-2025, https://doi.org/10.5194/acp-25-1121-2025, 2025
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In urban areas, emissions from everyday products like paints, cleaners, and personal care products, along with non-traditional sources such as cooking, are increasingly important and impact air quality. This study uses a box model to evaluate how these emissions impact ozone in the Los Angeles Basin and quantifies the impact of gaseous cooking emissions. Accurate representation of these and other anthropogenic sources in inventories is crucial for informing effective air quality policies.
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.
Alex T. Archibald, Bablu Sinha, Maria R. Russo, Emily Matthews, Freya A. Squires, N. Luke Abraham, Stephane J.-B. Bauguitte, Thomas J. Bannan, Thomas G. Bell, David Berry, Lucy J. Carpenter, Hugh Coe, Andrew Coward, Peter Edwards, Daniel Feltham, Dwayne Heard, Jim Hopkins, James Keeble, Elizabeth C. Kent, Brian A. King, Isobel R. Lawrence, James Lee, Claire R. Macintosh, Alex Megann, Bengamin I. Moat, Katie Read, Chris Reed, Malcolm J. Roberts, Reinhard Schiemann, David Schroeder, Timothy J. Smyth, Loren Temple, Navaneeth Thamban, Lisa Whalley, Simon Williams, Huihui Wu, and Mingxi Yang
Earth Syst. Sci. Data, 17, 135–164, https://doi.org/10.5194/essd-17-135-2025, https://doi.org/10.5194/essd-17-135-2025, 2025
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Here, we present an overview of the data generated as part of the North Atlantic Climate System Integrated Study (ACSIS) programme that are available through dedicated repositories at the Centre for Environmental Data Analysis (CEDA; www.ceda.ac.uk) and the British Oceanographic Data Centre (BODC; bodc.ac.uk). The datasets described here cover the North Atlantic Ocean, the atmosphere above (it including its composition), and Arctic sea ice.
Gregory P. Schill, Karl D. Froyd, Daniel M. Murphy, Christina J. Williamson, Charles A. Brock, Tomás Sherwen, Mat J. Evans, Eric A. Ray, Eric C. Apel, Rebecca S. Hornbrook, Alan J. Hills, Jeff Peischl, Thomas B. Ryerson, Chelsea R. Thompson, Ilann Bourgeois, Donald R. Blake, Joshua P. DiGangi, and Glenn S. Diskin
Atmos. Chem. Phys., 25, 45–71, https://doi.org/10.5194/acp-25-45-2025, https://doi.org/10.5194/acp-25-45-2025, 2025
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Using single-particle mass spectrometry, we show that trace concentrations of bromine and iodine are ubiquitous in remote tropospheric aerosol and suggest that aerosols are an important part of the global reactive iodine budget. Comparisons to a global climate model with detailed iodine chemistry are favorable in the background atmosphere; however, the model cannot replicate our measurements near the ocean surface, in biomass burning plumes, and in the stratosphere.
Simone T. Andersen, Max R. McGillen, Chaoyang Xue, Tobias Seubert, Patrick Dewald, Gunther N. T. E. Türk, Jan Schuladen, Cyrielle Denjean, Jean-Claude Etienne, Olivier Garrouste, Marina Jamar, Sergio Harb, Manuela Cirtog, Vincent Michoud, Mathieu Cazaunau, Antonin Bergé, Christopher Cantrell, Sebastien Dusanter, Bénédicte Picquet-Varrault, Alexandre Kukui, Abdelwahid Mellouki, Lucy J. Carpenter, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 24, 11603–11618, https://doi.org/10.5194/acp-24-11603-2024, https://doi.org/10.5194/acp-24-11603-2024, 2024
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Using measurements of various trace gases in a suburban forest near Paris in the summer of 2022, we were able to gain insight into the sources and sinks of NOx (NO+NO2) with a special focus on their nighttime chemical and physical loss processes. NO was observed as a result of nighttime soil emissions when O3 levels were strongly depleted by deposition. NO oxidation products were not observed at night, indicating that soil and/or foliar surfaces are an efficient sink of reactive N.
Henning Finkenzeller, Jyri Mikkilä, Cecilia Righi, Paxton Juuti, Mikko Sipilä, Matti Rissanen, Douglas Worsnop, Aleksei Shcherbinin, Nina Sarnela, and Juha Kangasluoma
Atmos. Meas. Tech., 17, 5989–6001, https://doi.org/10.5194/amt-17-5989-2024, https://doi.org/10.5194/amt-17-5989-2024, 2024
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Chemical ionisation mass spectrometry is used in the atmospheric sciences to measure trace gas concentrations. Neutral gases require charging in inlets before the mass-to-charge ratio of the resulting ions can be analysed. This study uses multiphysics modelling to investigate how the MION2 and Eisele type inlets work and shows the effect of tuning parameters and their current limitations. The findings are helpful for inlet users and are expected to aid in developing improved inlets.
Sankirna D. Joge, Anoop S. Mahajan, Shrivardhan Hulswar, Christa A. Marandino, Martí Galí, Thomas G. Bell, Mingxi Yang, and Rafel Simó
Biogeosciences, 21, 4453–4467, https://doi.org/10.5194/bg-21-4453-2024, https://doi.org/10.5194/bg-21-4453-2024, 2024
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Dimethyl sulfide (DMS) is the largest natural source of sulfur in the atmosphere and leads to the formation of cloud condensation nuclei. DMS emissions and quantification of their impacts have large uncertainties, but a detailed study on the range of emissions and drivers of their uncertainty is missing to date. The emissions are calculated from the seawater DMS concentrations and a flux parameterization. Here we quantify the differences in the effect of flux parameterizations used in models.
Sankirna D. Joge, Anoop S. Mahajan, Shrivardhan Hulswar, Christa A. Marandino, Martí Galí, Thomas G. Bell, and Rafel Simó
Biogeosciences, 21, 4439–4452, https://doi.org/10.5194/bg-21-4439-2024, https://doi.org/10.5194/bg-21-4439-2024, 2024
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Dimethyl sulfide (DMS) is the largest natural source of sulfur in the atmosphere and leads to the formation of cloud condensation nuclei. DMS emission and quantification of its impacts have large uncertainties, but a detailed study on the emissions and drivers of their uncertainty is missing to date. The emissions are usually calculated from the seawater DMS concentrations and a flux parameterization. Here we quantify the differences in DMS seawater products, which can affect DMS fluxes.
Theodore K. Koenig, François Hendrick, Douglas Kinnison, Christopher F. Lee, Michel Van Roozendael, and Rainer Volkamer
Atmos. Meas. Tech., 17, 5911–5934, https://doi.org/10.5194/amt-17-5911-2024, https://doi.org/10.5194/amt-17-5911-2024, 2024
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Atmospheric bromine destroys ozone, impacts oxidation capacity, and oxidizes mercury into its toxic form. We constrain bromine by remote sensing of BrO from a mountaintop. Previous measurements retrieved two to three pieces of information vertically; we apply new methods to get five and a half vertically and two more in time. We compare with aircraft measurements to validate the methods and look at variations in BrO over the Pacific.
Matthieu Riva, Veronika Pospisilova, Carla Frege, Sebastien Perrier, Priyanka Bansal, Spiro Jorga, Patrick Sturm, Joel A. Thornton, Urs Rohner, and Felipe Lopez-Hilfiker
Atmos. Meas. Tech., 17, 5887–5901, https://doi.org/10.5194/amt-17-5887-2024, https://doi.org/10.5194/amt-17-5887-2024, 2024
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We present a newly designed reduced-pressure chemical ionization reactor for detection of gas-phase organic and inorganic species. The system operates through the combined use of vacuum ultraviolet ionization and photosensitizers to generate numerous adduct ionization schemes. As a result, it offers the ability to simultaneously measure a wide variety of organic and inorganic species in terms of compound volatility and functionality, while being largely independent of changes in sample humidity.
Randall Chiu, Florian Obersteiner, Alessandro Franchin, Teresa Campos, Adriana Bailey, Christopher Webster, Andreas Zahn, and Rainer Volkamer
Atmos. Meas. Tech., 17, 5731–5746, https://doi.org/10.5194/amt-17-5731-2024, https://doi.org/10.5194/amt-17-5731-2024, 2024
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The ozone sink into oceans and marine clouds is seldom studied and highly uncertain. Calculations suggest O3 destruction at aqueous surfaces (ocean, droplets) may be strongly accelerated, but field evidence is missing. Here we compare three fast airborne O3 instruments to measure eddy covariance fluxes of O3 over the remote ocean, in clear and cloudy air. We find O3 fluxes below clouds are consistently directed into clouds, while O3 fluxes into oceans are much smaller and spatially variable.
Ryan J. Pound, Lucy V. Brown, Mat J. Evans, and Lucy J. Carpenter
Atmos. Chem. Phys., 24, 9899–9921, https://doi.org/10.5194/acp-24-9899-2024, https://doi.org/10.5194/acp-24-9899-2024, 2024
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Iodine-mediated loss of ozone to the ocean surface and the subsequent emission of iodine species has a large effect on the troposphere. Here we combine recent experimental insights to develop a box model of the process, which we then parameterize and incorporate into the GEOS-Chem transport model. We find that these new insights have a small impact on the total emission of iodine but significantly change its distribution.
Andrew O. Langford, Raul J. Alvarez II, Kenneth C. Aikin, Sunil Baidar, W. Alan Brewer, Steven S. Brown, Matthew M. Coggan, Patrick D. Cullis, Jessica Gilman, Georgios I. Gkatzelis, Detlev Helmig, Bryan J. Johnson, K. Emma Knowland, Rajesh Kumar, Aaron D. Lamplugh, Audra McClure-Begley, Brandi J. McCarty, Ann M. Middlebrook, Gabriele Pfister, Jeff Peischl, Irina Petropavlovskikh, Pamela S. Rickley, Andrew W. Rollins, Scott P. Sandberg, Christoph J. Senff, and Carsten Warneke
EGUsphere, https://doi.org/10.5194/egusphere-2024-1938, https://doi.org/10.5194/egusphere-2024-1938, 2024
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High ozone (O3) formed by reactions of nitrogen oxides (NOx) and volatile organic compounds (VOCs) can harm human health and welfare. High O3 is usually associated with hot summer days, but under certain conditions, high O3 can also form under winter conditions. In this study, we describe a high O3 event that occurred in Colorado during the COVID-19 quarantine that was caused in part by the decrease in traffic, and in part by a shallow inversion created by descent of stratospheric air.
Eleanor J. Derry, Tyler R. Elgiar, Taylor Y. Wilmot, Nicholas W. Hoch, Noah S. Hirshorn, Peter Weiss-Penzias, Christopher F. Lee, John C. Lin, A. Gannet Hallar, Rainer Volkamer, Seth N. Lyman, and Lynne E. Gratz
Atmos. Chem. Phys., 24, 9615–9643, https://doi.org/10.5194/acp-24-9615-2024, https://doi.org/10.5194/acp-24-9615-2024, 2024
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Mercury (Hg) is a globally distributed neurotoxic pollutant. Atmospheric deposition is the main source of Hg in ecosystems. However, measurement biases hinder understanding of the origins and abundance of the more bioavailable oxidized form. We used an improved, calibrated measurement system to study air mass composition and transport of atmospheric Hg at a remote mountaintop site in the central US. Oxidized Hg originated upwind in the low to middle free troposphere under clean, dry conditions.
Katherine R. Travis, Benjamin A. Nault, James H. Crawford, Kelvin H. Bates, Donald R. Blake, Ronald C. Cohen, Alan Fried, Samuel R. Hall, L. Gregory Huey, Young Ro Lee, Simone Meinardi, Kyung-Eun Min, Isobel J. Simpson, and Kirk Ullman
Atmos. Chem. Phys., 24, 9555–9572, https://doi.org/10.5194/acp-24-9555-2024, https://doi.org/10.5194/acp-24-9555-2024, 2024
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Human activities result in the emission of volatile organic compounds (VOCs) that contribute to air pollution. Detailed VOC measurements were taken during a field study in South Korea. When compared to VOC inventories, large discrepancies showed underestimates from chemical products, liquefied petroleum gas, and long-range transport. Improved emissions and chemistry of these VOCs better described urban pollution. The new chemical scheme is relevant to urban areas and other VOC sources.
Matthew J. Rowlinson, Mat J. Evans, Lucy J. Carpenter, Katie A. Read, Shalini Punjabi, Adedayo Adedeji, Luke Fakes, Ally Lewis, Ben Richmond, Neil Passant, Tim Murrells, Barron Henderson, Kelvin H. Bates, and Detlev Helmig
Atmos. Chem. Phys., 24, 8317–8342, https://doi.org/10.5194/acp-24-8317-2024, https://doi.org/10.5194/acp-24-8317-2024, 2024
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Ethane and propane are volatile organic compounds emitted from human activities which help to form ozone, a pollutant and greenhouse gas, and also affect the chemistry of the lower atmosphere. Atmospheric models tend to do a poor job of reproducing the abundance of these compounds in the atmosphere. By using regional estimates of their emissions, rather than globally consistent estimates, we can significantly improve the simulation of ethane in the model and make some improvement for propane.
Maya Abou-Ghanem, Daniel M. Murphy, Gregory P. Schill, Michael J. Lawler, and Karl D. Froyd
Atmos. Chem. Phys., 24, 8263–8275, https://doi.org/10.5194/acp-24-8263-2024, https://doi.org/10.5194/acp-24-8263-2024, 2024
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Using particle analysis by laser mass spectrometry, we examine vanadium-containing ship exhaust particles measured on NASA's DC-8 during the Atmospheric Tomography Mission (ATom). Our results reveal ship exhaust particles are sufficiently widespread in the marine atmosphere and experience atmospheric aging. Finally, we use laboratory calibrations to determine the vanadium, sulfate, and organic single-particle mass fractions of vanadium-containing ship exhaust particles.
Chuanyang Shen, Xiaoyan Yang, Joel Thornton, John Shilling, Chenyang Bi, Gabriel Isaacman-VanWertz, and Haofei Zhang
Atmos. Chem. Phys., 24, 6153–6175, https://doi.org/10.5194/acp-24-6153-2024, https://doi.org/10.5194/acp-24-6153-2024, 2024
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In this work, a condensed multiphase isoprene oxidation mechanism was developed to simulate isoprene SOA formation from chamber and field studies. Our results show that the measured isoprene SOA mass concentrations can be reasonably reproduced. The simulation results indicate that multifunctional low-volatility products contribute significantly to total isoprene SOA. Our findings emphasize that the pathways to produce these low-volatility species should be considered in models.
Katrine A. Gorham, Sam Abernethy, Tyler R. Jones, Peter Hess, Natalie M. Mahowald, Daphne Meidan, Matthew S. Johnson, Maarten M. J. W. van Herpen, Yangyang Xu, Alfonso Saiz-Lopez, Thomas Röckmann, Chloe A. Brashear, Erika Reinhardt, and David Mann
Atmos. Chem. Phys., 24, 5659–5670, https://doi.org/10.5194/acp-24-5659-2024, https://doi.org/10.5194/acp-24-5659-2024, 2024
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Rapid reduction in atmospheric methane is needed to slow the rate of global warming. Reducing anthropogenic methane emissions is a top priority. However, atmospheric methane is also impacted by rising natural emissions and changing sinks. Studies of possible atmospheric methane removal approaches, such as iron salt aerosols to increase the chlorine radical sink, benefit from a roadmapped approach to understand if there may be viable and socially acceptable ways to decrease future risk.
Heesung Chong, Gonzalo González Abad, Caroline R. Nowlan, Christopher Chan Miller, Alfonso Saiz-Lopez, Rafael P. Fernandez, Hyeong-Ahn Kwon, Zolal Ayazpour, Huiqun Wang, Amir H. Souri, Xiong Liu, Kelly Chance, Ewan O'Sullivan, Jhoon Kim, Ja-Ho Koo, William R. Simpson, François Hendrick, Richard Querel, Glen Jaross, Colin Seftor, and Raid M. Suleiman
Atmos. Meas. Tech., 17, 2873–2916, https://doi.org/10.5194/amt-17-2873-2024, https://doi.org/10.5194/amt-17-2873-2024, 2024
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We present a new bromine monoxide (BrO) product derived using radiances measured from OMPS-NM on board the Suomi-NPP satellite. This product provides nearly a decade of global stratospheric and tropospheric column retrievals, a feature that is currently rare in publicly accessible datasets. Both stratospheric and tropospheric columns from OMPS-NM demonstrate robust performance, exhibiting good agreement with ground-based observations collected at three stations (Lauder, Utqiagvik, and Harestua).
Zhuang Jiang, Becky Alexander, Joel Savarino, and Lei Geng
Atmos. Chem. Phys., 24, 4895–4914, https://doi.org/10.5194/acp-24-4895-2024, https://doi.org/10.5194/acp-24-4895-2024, 2024
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Ice-core nitrate could track the past atmospheric NOx and oxidant level, but its interpretation is hampered by the post-depositional processing. In this work, an inverse model was developed and tested against two polar sites and was shown to well reproduce the observed nitrate signals in snow and atmosphere, suggesting that the model can properly correct for the effect of post-depositional processing. This model offers a very useful tool for future studies on ice-core nitrate records.
Santo Fedele Colosimo, Nathaniel Brockway, Vijay Natraj, Robert Spurr, Klaus Pfeilsticker, Lisa Scalone, Max Spolaor, Sarah Woods, and Jochen Stutz
Atmos. Meas. Tech., 17, 2367–2385, https://doi.org/10.5194/amt-17-2367-2024, https://doi.org/10.5194/amt-17-2367-2024, 2024
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Cirrus clouds are poorly understood components of the climate system, in part due to the challenge of observing thin, sub-visible ice clouds. We address this issue with a new observational approach that uses the remote sensing of near-infrared ice water absorption features from a high-altitude aircraft. We describe the underlying principle of this approach and present a new procedure to retrieve ice concentration in cirrus clouds. Our retrievals compare well with in situ observations.
Lucy V. Brown, Ryan J. Pound, Lyndsay S. Ives, Matthew R. Jones, Stephen J. Andrews, and Lucy J. Carpenter
Atmos. Chem. Phys., 24, 3905–3923, https://doi.org/10.5194/acp-24-3905-2024, https://doi.org/10.5194/acp-24-3905-2024, 2024
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Ozone is deposited from the lower atmosphere to the surface of the ocean; however, the chemical reactions which drive this deposition are currently not well understood. Of particular importance is the reaction between ozone and iodide, and this work measures the kinetics of this reaction and its temperature dependence, which we find to be negligible. We then investigate the subsequent emissions of iodine-containing species from the surface ocean, which can further impact ozone.
Linia Tashmim, William C. Porter, Qianjie Chen, Becky Alexander, Charles H. Fite, Christopher D. Holmes, Jeffrey R. Pierce, Betty Croft, and Sakiko Ishino
Atmos. Chem. Phys., 24, 3379–3403, https://doi.org/10.5194/acp-24-3379-2024, https://doi.org/10.5194/acp-24-3379-2024, 2024
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Dimethyl sulfide (DMS) is mostly emitted from ocean surfaces and represents the largest natural source of sulfur for the atmosphere. Once in the atmosphere, DMS forms stable oxidation products such as SO2 and H2SO4, which can subsequently contribute to airborne particle formation and growth. In this study, we update the DMS oxidation mechanism in the chemical transport model GEOS-Chem and describe resulting changes in particle growth as well as the overall global sulfur budget.
Da Yang, Margarita Reza, Roy Mauldin, Rainer Volkamer, and Suresh Dhaniyala
Atmos. Meas. Tech., 17, 1463–1474, https://doi.org/10.5194/amt-17-1463-2024, https://doi.org/10.5194/amt-17-1463-2024, 2024
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This paper evaluates the performance of an aircraft gas inlet. Here, we use computational fluid dynamics (CFD) and experiments to demonstrate the role of turbulence in determining sampling performance of a gas inlet and identify ideal conditions for inlet operation to minimize gas loss. Experiments conducted in a high-speed wind tunnel under near-aircraft speeds validated numerical results. We believe that the results obtained from this work will greatly inform future gas inlet studies.
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.
Kelvin H. Bates, Mathew J. Evans, Barron H. Henderson, and Daniel J. Jacob
Geosci. Model Dev., 17, 1511–1524, https://doi.org/10.5194/gmd-17-1511-2024, https://doi.org/10.5194/gmd-17-1511-2024, 2024
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Accurate representation of rates and products of chemical reactions in atmospheric models is crucial for simulating concentrations of pollutants and climate forcers. We update the widely used GEOS-Chem atmospheric chemistry model with reaction parameters from recent compilations of experimental data and demonstrate the implications for key atmospheric chemical species. The updates decrease tropospheric CO mixing ratios and increase stratospheric nitrogen oxide mixing ratios, among other changes.
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.
Huisheng Bian, Mian Chin, Peter R. Colarco, Eric C. Apel, Donald R. Blake, Karl Froyd, Rebecca S. Hornbrook, Jose Jimenez, Pedro Campuzano Jost, Michael Lawler, Mingxu Liu, Marianne Tronstad Lund, Hitoshi Matsui, Benjamin A. Nault, Joyce E. Penner, Andrew W. Rollins, Gregory Schill, Ragnhild B. Skeie, Hailong Wang, Lu Xu, Kai Zhang, and Jialei Zhu
Atmos. Chem. Phys., 24, 1717–1741, https://doi.org/10.5194/acp-24-1717-2024, https://doi.org/10.5194/acp-24-1717-2024, 2024
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This work studies sulfur in the remote troposphere at global and seasonal scales using aircraft measurements and multi-model simulations. The goal is to understand the sulfur cycle over remote oceans, spread of model simulations, and observation–model discrepancies. Such an understanding and comparison with real observations are crucial to narrow down the uncertainties in model sulfur simulations and improve understanding of the sulfur cycle in atmospheric air quality, climate, and ecosystems.
Matthew M. Coggon, Chelsea E. Stockwell, Megan S. Claflin, Eva Y. Pfannerstill, Lu Xu, Jessica B. Gilman, Julia Marcantonio, Cong Cao, Kelvin Bates, Georgios I. Gkatzelis, Aaron Lamplugh, Erin F. Katz, Caleb Arata, Eric C. Apel, Rebecca S. Hornbrook, Felix Piel, Francesca Majluf, Donald R. Blake, Armin Wisthaler, Manjula Canagaratna, Brian M. Lerner, Allen H. Goldstein, John E. Mak, and Carsten Warneke
Atmos. Meas. Tech., 17, 801–825, https://doi.org/10.5194/amt-17-801-2024, https://doi.org/10.5194/amt-17-801-2024, 2024
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Mass spectrometry is a tool commonly used to measure air pollutants. This study evaluates measurement artifacts produced in the proton-transfer-reaction mass spectrometer. We provide methods to correct these biases and better measure compounds that degrade air quality.
Georgios I. Gkatzelis, Matthew M. Coggon, Chelsea E. Stockwell, Rebecca S. Hornbrook, Hannah Allen, Eric C. Apel, Megan M. Bela, Donald R. Blake, Ilann Bourgeois, Steven S. Brown, Pedro Campuzano-Jost, Jason M. St. Clair, James H. Crawford, John D. Crounse, Douglas A. Day, Joshua P. DiGangi, Glenn S. Diskin, Alan Fried, Jessica B. Gilman, Hongyu Guo, Johnathan W. Hair, Hannah S. Halliday, Thomas F. Hanisco, Reem Hannun, Alan Hills, L. Gregory Huey, Jose L. Jimenez, Joseph M. Katich, Aaron Lamplugh, Young Ro Lee, Jin Liao, Jakob Lindaas, Stuart A. McKeen, Tomas Mikoviny, Benjamin A. Nault, J. Andrew Neuman, John B. Nowak, Demetrios Pagonis, Jeff Peischl, Anne E. Perring, Felix Piel, Pamela S. Rickly, Michael A. Robinson, Andrew W. Rollins, Thomas B. Ryerson, Melinda K. Schueneman, Rebecca H. Schwantes, Joshua P. Schwarz, Kanako Sekimoto, Vanessa Selimovic, Taylor Shingler, David J. Tanner, Laura Tomsche, Krystal T. Vasquez, Patrick R. Veres, Rebecca Washenfelder, Petter Weibring, Paul O. Wennberg, Armin Wisthaler, Glenn M. Wolfe, Caroline C. Womack, Lu Xu, Katherine Ball, Robert J. Yokelson, and Carsten Warneke
Atmos. Chem. Phys., 24, 929–956, https://doi.org/10.5194/acp-24-929-2024, https://doi.org/10.5194/acp-24-929-2024, 2024
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This study reports emissions of gases and particles from wildfires. These emissions are related to chemical proxies that can be measured by satellite and incorporated into models to improve predictions of wildfire impacts on air quality and climate.
Meeta Cesler-Maloney, William Simpson, Jonas Kuhn, Jochen Stutz, Jennie Thomas, Tjarda Roberts, Deanna Huff, and Sol Cooperdock
EGUsphere, https://doi.org/10.5194/egusphere-2023-3082, https://doi.org/10.5194/egusphere-2023-3082, 2024
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We used a one-dimensional model to simulate how pollution in Fairbanks, Alaska, accumulates in shallow layers near the ground when temperature inversions are present. We find pollution accumulates in a 20 m to 50 m thick layer. The model agrees with observations of SO2 pollution using only home heating emissions sources, which shows that ground-based sources dominate sulfur pollution in downtown Fairbanks. Air residence times in downtown are only a few hours, limiting chemical transformations.
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.
Adedayo R. Adedeji, Stephen J. Andrews, Matthew J. Rowlinson, Mathew J. Evans, Alastair C. Lewis, Shigeru Hashimoto, Hitoshi Mukai, Hiroshi Tanimoto, Yasunori Tohjima, and Takuya Saito
Atmos. Chem. Phys., 23, 9229–9244, https://doi.org/10.5194/acp-23-9229-2023, https://doi.org/10.5194/acp-23-9229-2023, 2023
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We use the GEOS-Chem model to interpret observations of CO, C2H6, C3H8, NOx, NOy and O3 made from Hateruma Island in 2018. The model captures many synoptic-scale events and the seasonality of most pollutants at the site but underestimates C2H6 and C3H8 during the winter. These underestimates are unlikely to be reconciled by increases in biomass burning emissions but could be reconciled by increasing the Asian anthropogenic source of C2H6 and C3H8 by factors of around 2 and 3, respectively.
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.
Cyril Caram, Sophie Szopa, Anne Cozic, Slimane Bekki, Carlos A. Cuevas, and Alfonso Saiz-Lopez
Geosci. Model Dev., 16, 4041–4062, https://doi.org/10.5194/gmd-16-4041-2023, https://doi.org/10.5194/gmd-16-4041-2023, 2023
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We studied the role of halogenated compounds (containing chlorine, bromine and iodine), emitted by natural processes (mainly above the oceans), in the chemistry of the lower layers of the atmosphere. We introduced this relatively new chemistry in a three-dimensional climate–chemistry model and looked at how this chemistry will disrupt the ozone. We showed that the concentration of ozone decreases by 22 % worldwide and that of the atmospheric detergent, OH, by 8 %.
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.
Tobias Borsdorff, Teresa Campos, Natalie Kille, Kyle J. Zarzana, Rainer Volkamer, and Jochen Landgraf
Atmos. Meas. Tech., 16, 3027–3038, https://doi.org/10.5194/amt-16-3027-2023, https://doi.org/10.5194/amt-16-3027-2023, 2023
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ECMWF plans to assimilate TROPOMI CO with their CAMS-IFS model. This will constrain the total column and the vertical CO distribution of the model. To show this, we combine individual TROPOMI CO column retrievals with different vertical sensitivities and obtain a vertical CO concentration profile. We test the approach on three CO pollution events in comparison with CAMS-IFS simulations that do not assimilate TROPOMI CO data and in situ airborne measurements of the BB-FLUX campaign.
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.
George Manville, Thomas G. Bell, Jane P. Mulcahy, Rafel Simó, Martí Galí, Anoop S. Mahajan, Shrivardhan Hulswar, and Paul R. Halloran
Biogeosciences, 20, 1813–1828, https://doi.org/10.5194/bg-20-1813-2023, https://doi.org/10.5194/bg-20-1813-2023, 2023
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We present the first global investigation of controls on seawater dimethylsulfide (DMS) spatial variability over scales of up to 100 km. Sea surface height anomalies, density, and chlorophyll a help explain almost 80 % of DMS variability. The results suggest that physical and biogeochemical processes play an equally important role in controlling DMS variability. These data provide independent confirmation that existing parameterisations of seawater DMS concentration use appropriate variables.
Manon Rocco, Erin Dunne, Alexia Saint-Macary, Maija Peltola, Theresa Barthelmeß, Neill Barr, Karl Safi, Andrew Marriner, Stacy Deppeler, James Harnwell, Anja Engel, Aurélie Colomb, Alfonso Saiz-Lopez, Mike Harvey, Cliff S. Law, and Karine Sellegri
EGUsphere, https://doi.org/10.5194/egusphere-2023-516, https://doi.org/10.5194/egusphere-2023-516, 2023
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During the Sea2cloud campaign in the Southern Pacific Ocean, we measured air-sea emissions from phytopankton of two key atmospheric compounds: DMS and MeSH. These compounds are well-known to play a great role in atmospheric chemistry and climate. We see in this paper that these compounds are most emited by the nanophytoplankton population. We provide here parameters for climate models to predict future trends of the emissions of these compounds and their roles and impacts on the global warming.
Henning Finkenzeller, Denis Pöhler, Martin Horbanski, Johannes Lampel, and Ulrich Platt
Atmos. Meas. Tech., 16, 1343–1356, https://doi.org/10.5194/amt-16-1343-2023, https://doi.org/10.5194/amt-16-1343-2023, 2023
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Optical resonators enhance the light path in compact instruments, thereby improving their sensitivity. Determining the established path length in the instrument is a prerequisite for the accurate determination of trace gas concentrations but can be a significant complication in the use of such resonators. Here we show two calibration techniques which are relatively simple and free of consumables but still provide accurate calibrations. This facilitates the use of optical resonators.
Laura Hyesung Yang, Daniel J. Jacob, Nadia K. Colombi, Shixian Zhai, Kelvin H. Bates, Viral Shah, Ellie Beaudry, Robert M. Yantosca, Haipeng Lin, Jared F. Brewer, Heesung Chong, Katherine R. Travis, James H. Crawford, Lok N. Lamsal, Ja-Ho Koo, and Jhoon Kim
Atmos. Chem. Phys., 23, 2465–2481, https://doi.org/10.5194/acp-23-2465-2023, https://doi.org/10.5194/acp-23-2465-2023, 2023
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A geostationary satellite can now provide hourly NO2 vertical columns, and obtaining the NO2 vertical columns from space relies on NO2 vertical distribution from the chemical transport model (CTM). In this work, we update the CTM to better represent the chemistry environment so that the CTM can accurately provide NO2 vertical distribution. We also find that the changes in NO2 vertical distribution driven by a change in mixing depth play an important role in the NO2 column's diurnal variation.
François Burgay, Rafael Pedro Fernández, Delia Segato, Clara Turetta, Christopher S. Blaszczak-Boxe, Rachael H. Rhodes, Claudio Scarchilli, Virginia Ciardini, Carlo Barbante, Alfonso Saiz-Lopez, and Andrea Spolaor
The Cryosphere, 17, 391–405, https://doi.org/10.5194/tc-17-391-2023, https://doi.org/10.5194/tc-17-391-2023, 2023
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The paper presents the first ice-core record of bromine (Br) in the Antarctic plateau. By the observation of the ice core and the application of atmospheric chemical models, we investigate the behaviour of bromine after its deposition into the snowpack, with interest in the effect of UV radiation change connected to the formation of the ozone hole, the role of volcanic deposition, and the possible use of Br to reconstruct past sea ice changes from ice core collect in the inner Antarctic plateau.
Viral Shah, Daniel J. Jacob, Ruijun Dang, Lok N. Lamsal, Sarah A. Strode, Stephen D. Steenrod, K. Folkert Boersma, Sebastian D. Eastham, Thibaud M. Fritz, Chelsea Thompson, Jeff Peischl, Ilann Bourgeois, Ilana B. Pollack, Benjamin A. Nault, Ronald C. Cohen, Pedro Campuzano-Jost, Jose L. Jimenez, Simone T. Andersen, Lucy J. Carpenter, Tomás Sherwen, and Mat J. Evans
Atmos. Chem. Phys., 23, 1227–1257, https://doi.org/10.5194/acp-23-1227-2023, https://doi.org/10.5194/acp-23-1227-2023, 2023
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NOx in the free troposphere (above 2 km) affects global tropospheric chemistry and the retrieval and interpretation of satellite NO2 measurements. We evaluate free tropospheric NOx in global atmospheric chemistry models and find that recycling NOx from its reservoirs over the oceans is faster than that simulated in the models, resulting in increases in simulated tropospheric ozone and OH. Over the U.S., free tropospheric NO2 contributes the majority of the tropospheric NO2 column in summer.
Siegfried Schobesberger, Emma L. D'Ambro, Lejish Vettikkat, Ben H. Lee, Qiaoyun Peng, David M. Bell, John E. Shilling, Manish Shrivastava, Mikhail Pekour, Jerome Fast, and Joel A. Thornton
Atmos. Meas. Tech., 16, 247–271, https://doi.org/10.5194/amt-16-247-2023, https://doi.org/10.5194/amt-16-247-2023, 2023
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We present a new, highly sensitive technique for measuring atmospheric ammonia, an important trace gas that is emitted mainly by agriculture. We deployed the instrument on an aircraft during research flights over rural Oklahoma. Due to its fast response, we could analyze correlations with turbulent winds and calculate ammonia emissions from nearby areas at 1 to 2 km resolution. We observed high spatial variability and point sources that are not resolved in the US National Emissions Inventory.
Simone T. Andersen, Beth S. Nelson, Katie A. Read, Shalini Punjabi, Luis Neves, Matthew J. Rowlinson, James Hopkins, Tomás Sherwen, Lisa K. Whalley, James D. Lee, and Lucy J. Carpenter
Atmos. Chem. Phys., 22, 15747–15765, https://doi.org/10.5194/acp-22-15747-2022, https://doi.org/10.5194/acp-22-15747-2022, 2022
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The cycling of NO and NO2 is important to understand to be able to predict O3 concentrations in the atmosphere. We have used long-term measurements from the Cape Verde Atmospheric Observatory together with model outputs to investigate the cycling of nitrogen oxide (NO) and nitrogen dioxide (NO2) in very clean marine air. This study shows that we understand the processes occurring in very clean air, but with small amounts of pollution in the air, known chemistry cannot explain what is observed.
Pamela S. Rickly, Hongyu Guo, Pedro Campuzano-Jost, Jose L. Jimenez, Glenn M. Wolfe, Ryan Bennett, Ilann Bourgeois, John D. Crounse, Jack E. Dibb, Joshua P. DiGangi, Glenn S. Diskin, Maximilian Dollner, Emily M. Gargulinski, Samuel R. Hall, Hannah S. Halliday, Thomas F. Hanisco, Reem A. Hannun, Jin Liao, Richard Moore, Benjamin A. Nault, John B. Nowak, Jeff Peischl, Claire E. Robinson, Thomas Ryerson, Kevin J. Sanchez, Manuel Schöberl, Amber J. Soja, Jason M. St. Clair, Kenneth L. Thornhill, Kirk Ullmann, Paul O. Wennberg, Bernadett Weinzierl, Elizabeth B. Wiggins, Edward L. Winstead, and Andrew W. Rollins
Atmos. Chem. Phys., 22, 15603–15620, https://doi.org/10.5194/acp-22-15603-2022, https://doi.org/10.5194/acp-22-15603-2022, 2022
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Biomass burning sulfur dioxide (SO2) emission factors range from 0.27–1.1 g kg-1 C. Biomass burning SO2 can quickly form sulfate and organosulfur, but these pathways are dependent on liquid water content and pH. Hydroxymethanesulfonate (HMS) appears to be directly emitted from some fire sources but is not the sole contributor to the organosulfur signal. It is shown that HMS and organosulfur chemistry may be an important S(IV) reservoir with the fate dependent on the surrounding conditions.
Markus Jesswein, Rafael P. Fernandez, Lucas Berná, Alfonso Saiz-Lopez, Jens-Uwe Grooß, Ryan Hossaini, Eric C. Apel, Rebecca S. Hornbrook, Elliot L. Atlas, Donald R. Blake, Stephen Montzka, Timo Keber, Tanja Schuck, Thomas Wagenhäuser, and Andreas Engel
Atmos. Chem. Phys., 22, 15049–15070, https://doi.org/10.5194/acp-22-15049-2022, https://doi.org/10.5194/acp-22-15049-2022, 2022
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This study presents the global and seasonal distribution of the two major brominated short-lived substances CH2Br2 and CHBr3 in the upper troposphere and lower stratosphere based on observations from several aircraft campaigns. They show similar seasonality for both hemispheres, except in the respective hemispheric autumn lower stratosphere. A comparison with the TOMCAT and CAM-Chem models shows good agreement in the annual mean but larger differences in the seasonal consideration.
Alfred W. Mayhew, Ben H. Lee, Joel A. Thornton, Thomas J. Bannan, James Brean, James R. Hopkins, James D. Lee, Beth S. Nelson, Carl Percival, Andrew R. Rickard, Marvin D. Shaw, Peter M. Edwards, and Jaqueline F. Hamilton
Atmos. Chem. Phys., 22, 14783–14798, https://doi.org/10.5194/acp-22-14783-2022, https://doi.org/10.5194/acp-22-14783-2022, 2022
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Isoprene nitrates are chemical species commonly found in the atmosphere that are important for their impacts on air quality and climate. This paper compares 3 different representations of the chemistry of isoprene nitrates in computational models highlighting cases where the choice of chemistry included has significant impacts on the concentration and composition of the modelled nitrates. Calibration of mass spectrometers is also shown to be an important factor when analysing isoprene nitrates.
William F. Swanson, Chris D. Holmes, William R. Simpson, Kaitlyn Confer, Louis Marelle, Jennie L. Thomas, Lyatt Jaeglé, Becky Alexander, Shuting Zhai, Qianjie Chen, Xuan Wang, and Tomás Sherwen
Atmos. Chem. Phys., 22, 14467–14488, https://doi.org/10.5194/acp-22-14467-2022, https://doi.org/10.5194/acp-22-14467-2022, 2022
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Radical bromine molecules are seen at higher concentrations during the Arctic spring. We use the global model GEOS-Chem to test whether snowpack and wind-blown snow sources can explain high bromine concentrations. We run this model for the entire year of 2015 and compare results to observations of bromine from floating platforms on the Arctic Ocean and at Utqiaġvik. We find that the model performs best when both sources are enabled but may overestimate bromine production in summer and fall.
Youhua Tang, Patrick C. Campbell, Pius Lee, Rick Saylor, Fanglin Yang, Barry Baker, Daniel Tong, Ariel Stein, Jianping Huang, Ho-Chun Huang, Li Pan, Jeff McQueen, Ivanka Stajner, Jose Tirado-Delgado, Youngsun Jung, Melissa Yang, Ilann Bourgeois, Jeff Peischl, Tom Ryerson, Donald Blake, Joshua Schwarz, Jose-Luis Jimenez, James Crawford, Glenn Diskin, Richard Moore, Johnathan Hair, Greg Huey, Andrew Rollins, Jack Dibb, and Xiaoyang Zhang
Geosci. Model Dev., 15, 7977–7999, https://doi.org/10.5194/gmd-15-7977-2022, https://doi.org/10.5194/gmd-15-7977-2022, 2022
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This paper compares two meteorological datasets for driving a regional air quality model: a regional meteorological model using WRF (WRF-CMAQ) and direct interpolation from an operational global model (GFS-CMAQ). In the comparison with surface measurements and aircraft data in summer 2019, these two methods show mixed performance depending on the corresponding meteorological settings. Direct interpolation is found to be a viable method to drive air quality models.
Xiao He, Xuan Zheng, Shaojun Zhang, Xuan Wang, Ting Chen, Xiao Zhang, Guanghan Huang, Yihuan Cao, Liqiang He, Xubing Cao, Yuan Cheng, Shuxiao Wang, and Ye Wu
Atmos. Chem. Phys., 22, 13935–13947, https://doi.org/10.5194/acp-22-13935-2022, https://doi.org/10.5194/acp-22-13935-2022, 2022
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With the use of two-dimensional gas chromatography time-of-flight mass spectrometry (GC × GC ToF-MS), we successfully give a comprehensive characterization of particulate intermediate-volatility and semi-volatile organic compounds (I/SVOCs) emitted from heavy-duty diesel vehicles. I/SVOCs are speciated, identified, and quantified based on the patterns of the mass spectrum, and the gas–particle partitioning is fully addressed.
Yanzhi Cao, Zhuang Jiang, Becky Alexander, Jihong Cole-Dai, Joel Savarino, Joseph Erbland, and Lei Geng
Atmos. Chem. Phys., 22, 13407–13422, https://doi.org/10.5194/acp-22-13407-2022, https://doi.org/10.5194/acp-22-13407-2022, 2022
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We investigate the potential of ice-core preserved nitrate isotopes as proxies of stratospheric ozone variability by measuring nitrate isotopes in a shallow ice core from the South Pole. The large variability in the snow accumulation rate and its slight increase after the 1970s masked any signals caused by the ozone hole. Moreover, the nitrate oxygen isotope decrease may reflect changes in the atmospheric oxidation environment in the Southern Ocean.
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.
Ilann Bourgeois, Jeff Peischl, J. Andrew Neuman, Steven S. Brown, Hannah M. Allen, Pedro Campuzano-Jost, Matthew M. Coggon, Joshua P. DiGangi, Glenn S. Diskin, Jessica B. Gilman, Georgios I. Gkatzelis, Hongyu Guo, Hannah A. Halliday, Thomas F. Hanisco, Christopher D. Holmes, L. Gregory Huey, Jose L. Jimenez, Aaron D. Lamplugh, Young Ro Lee, Jakob Lindaas, Richard H. Moore, Benjamin A. Nault, John B. Nowak, Demetrios Pagonis, Pamela S. Rickly, Michael A. Robinson, Andrew W. Rollins, Vanessa Selimovic, Jason M. St. Clair, David Tanner, Krystal T. Vasquez, Patrick R. Veres, Carsten Warneke, Paul O. Wennberg, Rebecca A. Washenfelder, Elizabeth B. Wiggins, Caroline C. Womack, Lu Xu, Kyle J. Zarzana, and Thomas B. Ryerson
Atmos. Meas. Tech., 15, 4901–4930, https://doi.org/10.5194/amt-15-4901-2022, https://doi.org/10.5194/amt-15-4901-2022, 2022
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Understanding fire emission impacts on the atmosphere is key to effective air quality management and requires accurate measurements. We present a comparison of airborne measurements of key atmospheric species in ambient air and in fire smoke. We show that most instruments performed within instrument uncertainties. In some cases, further work is needed to fully characterize instrument performance. Comparing independent measurements using different techniques is important to assess their accuracy.
Zhuang Jiang, Joel Savarino, Becky Alexander, Joseph Erbland, Jean-Luc Jaffrezo, and Lei Geng
The Cryosphere, 16, 2709–2724, https://doi.org/10.5194/tc-16-2709-2022, https://doi.org/10.5194/tc-16-2709-2022, 2022
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A record of year-round atmospheric nitrate isotopic composition along with snow nitrate isotopic data from Summit, Greenland, revealed apparent enrichments in nitrogen isotopes in snow nitrate compared to atmospheric nitrate, in addition to a relatively smaller degree of changes in oxygen isotopes. The results suggest that at this site post-depositional processing takes effect, which should be taken into account when interpreting ice-core nitrate isotope records.
Shrivardhan Hulswar, Rafel Simó, Martí Galí, Thomas G. Bell, Arancha Lana, Swaleha Inamdar, Paul R. Halloran, George Manville, and Anoop Sharad Mahajan
Earth Syst. Sci. Data, 14, 2963–2987, https://doi.org/10.5194/essd-14-2963-2022, https://doi.org/10.5194/essd-14-2963-2022, 2022
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The third climatological estimation of sea surface dimethyl sulfide (DMS) concentrations based on in situ measurements was created (DMS-Rev3). The update includes a much larger input dataset and includes improvements in the data unification, filtering, and smoothing algorithm. The DMS-Rev3 climatology provides more realistic monthly estimates of DMS, and shows significant regional differences compared to past climatologies.
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.
Katherine R. Travis, James H. Crawford, Gao Chen, Carolyn E. Jordan, Benjamin A. Nault, Hwajin Kim, Jose L. Jimenez, Pedro Campuzano-Jost, Jack E. Dibb, Jung-Hun Woo, Younha Kim, Shixian Zhai, Xuan Wang, Erin E. McDuffie, Gan Luo, Fangqun Yu, Saewung Kim, Isobel J. Simpson, Donald R. Blake, Limseok Chang, and Michelle J. Kim
Atmos. Chem. Phys., 22, 7933–7958, https://doi.org/10.5194/acp-22-7933-2022, https://doi.org/10.5194/acp-22-7933-2022, 2022
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The 2016 Korea–United States Air Quality (KORUS-AQ) field campaign provided a unique set of observations to improve our understanding of PM2.5 pollution in South Korea. Models typically have errors in simulating PM2.5 in this region, which is of concern for the development of control measures. We use KORUS-AQ observations to improve our understanding of the mechanisms driving PM2.5 and the implications of model errors for determining PM2.5 that is attributable to local or foreign sources.
Susann Tegtmeier, Christa Marandino, Yue Jia, Birgit Quack, and Anoop S. Mahajan
Atmos. Chem. Phys., 22, 6625–6676, https://doi.org/10.5194/acp-22-6625-2022, https://doi.org/10.5194/acp-22-6625-2022, 2022
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In the atmosphere over the Indian Ocean, intense anthropogenic pollution from Southeast Asia mixes with pristine oceanic air. During the winter monsoon, high pollution levels are regularly observed over the entire northern Indian Ocean, while during the summer monsoon, clean air dominates. Here, we review current progress in detecting and understanding atmospheric gas-phase composition over the Indian Ocean and its impacts on the upper atmosphere, oceanic biogeochemistry, and marine ecosystems.
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.
Hannah Walker, Daniel Stone, Trevor Ingham, Sina Hackenberg, Danny Cryer, Shalini Punjabi, Katie Read, James Lee, Lisa Whalley, Dominick V. Spracklen, Lucy J. Carpenter, Steve R. Arnold, and Dwayne E. Heard
Atmos. Chem. Phys., 22, 5535–5557, https://doi.org/10.5194/acp-22-5535-2022, https://doi.org/10.5194/acp-22-5535-2022, 2022
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Glyoxal is a ubiquitous reactive organic compound in the atmosphere, which may form organic aerosol and impact the atmosphere's oxidising capacity. There are limited measurements of glyoxal's abundance in the remote marine atmosphere. We made new measurements of glyoxal using a highly sensitive technique over two 4-week periods in the tropical Atlantic atmosphere. We show that daytime measurements are mostly consistent with our chemical understanding but a potential missing source at night.
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.
Hisahiro Takashima, Yugo Kanaya, Saki Kato, Martina M. Friedrich, Michel Van Roozendael, Fumikazu Taketani, Takuma Miyakawa, Yuichi Komazaki, Carlos A. Cuevas, Alfonso Saiz-Lopez, and Takashi Sekiya
Atmos. Chem. Phys., 22, 4005–4018, https://doi.org/10.5194/acp-22-4005-2022, https://doi.org/10.5194/acp-22-4005-2022, 2022
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We have undertaken atmospheric iodine monoxide (IO) observations in the global marine boundary layer with a wide latitudinal coverage and sea surface temperature (SST) range. We conclude that atmospheric iodine is abundant over the Western Pacific warm pool, appearing as an iodine fountain, where ozone (O3) minima occur. Our study also found negative correlations between IO and O3 concentrations over IO maxima, which requires reconsideration of the initiation process of halogen activation.
Martin Breitenlechner, Gordon A. Novak, J. Andrew Neuman, Andrew W. Rollins, and Patrick R. Veres
Atmos. Meas. Tech., 15, 1159–1169, https://doi.org/10.5194/amt-15-1159-2022, https://doi.org/10.5194/amt-15-1159-2022, 2022
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We coupled a new ion source to a commercially available state-of-the-art trace gas analyzer. The instrument is particularly well suited for conducting high-altitude observations, addressing the challenges of low ambient pressures and a complex sample matrix. The new instrument and ion source provides significant advantages to more traditional modes of operation, without sacrificing the sensitivity and flexibility of this technique.
Lu Shen, Daniel J. Jacob, Mauricio Santillana, Kelvin Bates, Jiawei Zhuang, and Wei Chen
Geosci. Model Dev., 15, 1677–1687, https://doi.org/10.5194/gmd-15-1677-2022, https://doi.org/10.5194/gmd-15-1677-2022, 2022
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The high computational cost of chemical integration is a long-standing limitation in global atmospheric chemistry models. Here we present an adaptive and efficient algorithm that can reduce the computational time of atmospheric chemistry by 50 % and maintain the error below 2 % for important species, inspired by machine learning clustering techniques and traditional asymptotic analysis ideas.
Haichao Wang, Chao Peng, Xuan Wang, Shengrong Lou, Keding Lu, Guicheng Gan, Xiaohong Jia, Xiaorui Chen, Jun Chen, Hongli Wang, Shaojia Fan, Xinming Wang, and Mingjin Tang
Atmos. Chem. Phys., 22, 1845–1859, https://doi.org/10.5194/acp-22-1845-2022, https://doi.org/10.5194/acp-22-1845-2022, 2022
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Via combining laboratory and modeling work, we found that heterogeneous reaction of N2O5 with saline mineral dust aerosol could be an important source of tropospheric ClNO2 in inland regions.
Zhiyuan Gao, Nicolas-Xavier Geilfus, Alfonso Saiz-Lopez, and Feiyue Wang
Atmos. Chem. Phys., 22, 1811–1824, https://doi.org/10.5194/acp-22-1811-2022, https://doi.org/10.5194/acp-22-1811-2022, 2022
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Every spring in the Arctic, a series of photochemical events occur over the ice-covered ocean, known as bromine explosion events, ozone depletion events, and mercury depletion events. Here we report the re-creation of these events at an outdoor sea ice facility in Winnipeg, Canada, far away from the Arctic. The success provides a new platform with new opportunities to uncover fundamental mechanisms of these Arctic springtime phenomena and how they may change in a changing climate.
Kelvin H. Bates, Guy J. P. Burke, James D. Cope, and Tran B. Nguyen
Atmos. Chem. Phys., 22, 1467–1482, https://doi.org/10.5194/acp-22-1467-2022, https://doi.org/10.5194/acp-22-1467-2022, 2022
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The main nighttime sink of α-pinene, a hydrocarbon abundantly emitted by plants, is reaction with NO3 to form nitrooxy peroxy radicals (nRO2). Using uniquely designed chamber experiments, we show that this reaction is a major source of organic aerosol when nRO2 reacts with other nRO2 and forms a nitrooxy hydroperoxide when nRO2 reacts with HO2. Under ambient conditions these pathways are key loss processes of atmospheric reactive nitrogen in areas with mixed biogenic and anthropogenic influence.
Dongwook Kim, Changmin Cho, Seokhan Jeong, Soojin Lee, Benjamin A. Nault, Pedro Campuzano-Jost, Douglas A. Day, Jason C. Schroder, Jose L. Jimenez, Rainer Volkamer, Donald R. Blake, Armin Wisthaler, Alan Fried, Joshua P. DiGangi, Glenn S. Diskin, Sally E. Pusede, Samuel R. Hall, Kirk Ullmann, L. Gregory Huey, David J. Tanner, Jack Dibb, Christoph J. Knote, and Kyung-Eun Min
Atmos. Chem. Phys., 22, 805–821, https://doi.org/10.5194/acp-22-805-2022, https://doi.org/10.5194/acp-22-805-2022, 2022
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CHOCHO was simulated using a 0-D box model constrained by measurements during the KORUS-AQ mission. CHOCHO concentration was high in large cities, aromatics being the most important precursors. Loss path to aerosol was the highest sink, contributing to ~ 20 % of secondary organic aerosol formation. Our work highlights that simple CHOCHO surface uptake approach is valid only for low aerosol conditions and more work is required to understand CHOCHO solubility in high-aerosol conditions.
Dalrin Ampritta Amaladhasan, Claudia Heyn, Christopher R. Hoyle, Imad El Haddad, Miriam Elser, Simone M. Pieber, Jay G. Slowik, Antonio Amorim, Jonathan Duplissy, Sebastian Ehrhart, Vladimir Makhmutov, Ugo Molteni, Matti Rissanen, Yuri Stozhkov, Robert Wagner, Armin Hansel, Jasper Kirkby, Neil M. Donahue, Rainer Volkamer, Urs Baltensperger, Martin Gysel-Beer, and Andreas Zuend
Atmos. Chem. Phys., 22, 215–244, https://doi.org/10.5194/acp-22-215-2022, https://doi.org/10.5194/acp-22-215-2022, 2022
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We use a combination of models for gas-phase chemical reactions and equilibrium gas–particle partitioning of isoprene-derived secondary organic aerosols (SOAs) informed by dark ozonolysis experiments conducted in the CLOUD chamber. Our predictions cover high to low relative humidities (RHs) and quantify how SOA mass yields are enhanced at high RH as well as the impact of inorganic seeds of distinct hygroscopicities and acidities on the coupled partitioning of water and semi-volatile organics.
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.
Debora Griffin, Chris A. McLinden, Enrico Dammers, Cristen Adams, Chelsea E. Stockwell, Carsten Warneke, Ilann Bourgeois, Jeff Peischl, Thomas B. Ryerson, Kyle J. Zarzana, Jake P. Rowe, Rainer Volkamer, Christoph Knote, Natalie Kille, Theodore K. Koenig, Christopher F. Lee, Drew Rollins, Pamela S. Rickly, Jack Chen, Lukas Fehr, Adam Bourassa, Doug Degenstein, Katherine Hayden, Cristian Mihele, Sumi N. Wren, John Liggio, Ayodeji Akingunola, and Paul Makar
Atmos. Meas. Tech., 14, 7929–7957, https://doi.org/10.5194/amt-14-7929-2021, https://doi.org/10.5194/amt-14-7929-2021, 2021
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Satellite-derived NOx emissions from biomass burning are estimated with TROPOMI observations. Two common emission estimation methods are applied, and sensitivity tests with model output were performed to determine the accuracy of these methods. The effect of smoke aerosols on TROPOMI NO2 columns is estimated and compared to aircraft observations from four different aircraft campaigns measuring biomass burning plumes in 2018 and 2019 in North America.
Kelvin H. Bates, Daniel J. Jacob, Ke Li, Peter D. Ivatt, Mat J. Evans, Yingying Yan, and Jintai Lin
Atmos. Chem. Phys., 21, 18351–18374, https://doi.org/10.5194/acp-21-18351-2021, https://doi.org/10.5194/acp-21-18351-2021, 2021
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Simple aromatic compounds (benzene, toluene, xylene) have complex gas-phase chemistry that is inconsistently represented in atmospheric models. We compile recent experimental and theoretical insights to develop a new mechanism for gas-phase aromatic oxidation that is sufficiently compact for use in multiscale models. We compare our new mechanism to chamber experiments and other mechanisms, and implement it in a global model to quantify the impacts of aromatic oxidation on tropospheric chemistry.
Leigh R. Crilley, Louisa J. Kramer, Francis D. Pope, Chris Reed, James D. Lee, Lucy J. Carpenter, Lloyd D. J. Hollis, Stephen M. Ball, and William J. Bloss
Atmos. Chem. Phys., 21, 18213–18225, https://doi.org/10.5194/acp-21-18213-2021, https://doi.org/10.5194/acp-21-18213-2021, 2021
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Nitrous acid (HONO) is a key source of atmospheric oxidants. We evaluate if the ocean surface is a source of HONO for the marine boundary layer, using measurements from two contrasting coastal locations. We observed no evidence for a night-time ocean surface source, in contrast to previous work. This points to significant geographical variation in the predominant HONO formation mechanisms in marine environments, reflecting possible variability in the sea-surface microlayer composition.
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.
Sharmine Akter Simu, Yuzo Miyazaki, Eri Tachibana, Henning Finkenzeller, Jérôme Brioude, Aurélie Colomb, Olivier Magand, Bert Verreyken, Stephanie Evan, Rainer Volkamer, and Trissevgeni Stavrakou
Atmos. Chem. Phys., 21, 17017–17029, https://doi.org/10.5194/acp-21-17017-2021, https://doi.org/10.5194/acp-21-17017-2021, 2021
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The tropical Indian Ocean (IO) is expected to be a significant source of water-soluble organic carbon (WSOC), which is relevant to cloud formation. Our study showed that marine secondary organic formation dominantly contributed to the aerosol WSOC mass at the high-altitude observatory in the southwest IO in the wet season in both marine boundary layer and free troposphere (FT). This suggests that the effect of marine secondary sources is important up to FT, a process missing in climate models.
Shixian Zhai, Daniel J. Jacob, Jared F. Brewer, Ke Li, Jonathan M. Moch, Jhoon Kim, Seoyoung Lee, Hyunkwang Lim, Hyun Chul Lee, Su Keun Kuk, Rokjin J. Park, Jaein I. Jeong, Xuan Wang, Pengfei Liu, Gan Luo, Fangqun Yu, Jun Meng, Randall V. Martin, Katherine R. Travis, Johnathan W. Hair, Bruce E. Anderson, Jack E. Dibb, Jose L. Jimenez, Pedro Campuzano-Jost, Benjamin A. Nault, Jung-Hun Woo, Younha Kim, Qiang Zhang, and Hong Liao
Atmos. Chem. Phys., 21, 16775–16791, https://doi.org/10.5194/acp-21-16775-2021, https://doi.org/10.5194/acp-21-16775-2021, 2021
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Geostationary satellite aerosol optical depth (AOD) has tremendous potential for monitoring surface fine particulate matter (PM2.5). Our study explored the physical relationship between AOD and PM2.5 by integrating data from surface networks, aircraft, and satellites with the GEOS-Chem chemical transport model. We quantitatively showed that accurate simulation of aerosol size distributions, boundary layer depths, relative humidity, coarse particles, and diurnal variations in PM2.5 are essential.
Zachary C. J. Decker, Michael A. Robinson, Kelley C. Barsanti, Ilann Bourgeois, Matthew M. Coggon, Joshua P. DiGangi, Glenn S. Diskin, Frank M. Flocke, Alessandro Franchin, Carley D. Fredrickson, Georgios I. Gkatzelis, Samuel R. Hall, Hannah Halliday, Christopher D. Holmes, L. Gregory Huey, Young Ro Lee, Jakob Lindaas, Ann M. Middlebrook, Denise D. Montzka, Richard Moore, J. Andrew Neuman, John B. Nowak, Brett B. Palm, Jeff Peischl, Felix Piel, Pamela S. Rickly, Andrew W. Rollins, Thomas B. Ryerson, Rebecca H. Schwantes, Kanako Sekimoto, Lee Thornhill, Joel A. Thornton, Geoffrey S. Tyndall, Kirk Ullmann, Paul Van Rooy, Patrick R. Veres, Carsten Warneke, Rebecca A. Washenfelder, Andrew J. Weinheimer, Elizabeth Wiggins, Edward Winstead, Armin Wisthaler, Caroline Womack, and Steven S. Brown
Atmos. Chem. Phys., 21, 16293–16317, https://doi.org/10.5194/acp-21-16293-2021, https://doi.org/10.5194/acp-21-16293-2021, 2021
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To understand air quality impacts from wildfires, we need an accurate picture of how wildfire smoke changes chemically both day and night as sunlight changes the chemistry of smoke. We present a chemical analysis of wildfire smoke as it changes from midday through the night. We use aircraft observations from the FIREX-AQ field campaign with a chemical box model. We find that even under sunlight typical
nighttimechemistry thrives and controls the fate of key smoke plume chemical processes.
Arseniy Karagodin-Doyennel, Eugene Rozanov, Timofei Sukhodolov, Tatiana Egorova, Alfonso Saiz-Lopez, Carlos A. Cuevas, Rafael P. Fernandez, Tomás Sherwen, Rainer Volkamer, Theodore K. Koenig, Tanguy Giroud, and Thomas Peter
Geosci. Model Dev., 14, 6623–6645, https://doi.org/10.5194/gmd-14-6623-2021, https://doi.org/10.5194/gmd-14-6623-2021, 2021
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Here, we present the iodine chemistry module in the SOCOL-AERv2 model. The obtained iodine distribution demonstrated a good agreement when validated against other simulations and available observations. We also estimated the iodine influence on ozone in the case of present-day iodine emissions, the sensitivity of ozone to doubled iodine emissions, and when considering only organic or inorganic iodine sources. The new model can be used as a tool for further studies of iodine effects on ozone.
Eric J. Hintsa, Fred L. Moore, Dale F. Hurst, Geoff S. Dutton, Bradley D. Hall, J. David Nance, Ben R. Miller, Stephen A. Montzka, Laura P. Wolton, Audra McClure-Begley, James W. Elkins, Emrys G. Hall, Allen F. Jordan, Andrew W. Rollins, Troy D. Thornberry, Laurel A. Watts, Chelsea R. Thompson, Jeff Peischl, Ilann Bourgeois, Thomas B. Ryerson, Bruce C. Daube, Yenny Gonzalez Ramos, Roisin Commane, Gregory W. Santoni, Jasna V. Pittman, Steven C. Wofsy, Eric Kort, Glenn S. Diskin, and T. Paul Bui
Atmos. Meas. Tech., 14, 6795–6819, https://doi.org/10.5194/amt-14-6795-2021, https://doi.org/10.5194/amt-14-6795-2021, 2021
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We built UCATS to study atmospheric chemistry and transport. It has measured trace gases including CFCs, N2O, SF6, CH4, CO, and H2 with gas chromatography, as well as ozone and water vapor. UCATS has been part of missions to study the tropical tropopause; transport of air into the stratosphere; greenhouse gases, transport, and chemistry in the troposphere; and ozone chemistry, on both piloted and unmanned aircraft. Its design, capabilities, and some results are shown and described here.
Charles A. Brock, Karl D. Froyd, Maximilian Dollner, Christina J. Williamson, Gregory Schill, Daniel M. Murphy, Nicholas J. Wagner, Agnieszka Kupc, Jose L. Jimenez, Pedro Campuzano-Jost, Benjamin A. Nault, Jason C. Schroder, Douglas A. Day, Derek J. Price, Bernadett Weinzierl, Joshua P. Schwarz, Joseph M. Katich, Siyuan Wang, Linghan Zeng, Rodney Weber, Jack Dibb, Eric Scheuer, Glenn S. Diskin, Joshua P. DiGangi, ThaoPaul Bui, Jonathan M. Dean-Day, Chelsea R. Thompson, Jeff Peischl, Thomas B. Ryerson, Ilann Bourgeois, Bruce C. Daube, Róisín Commane, and Steven C. Wofsy
Atmos. Chem. Phys., 21, 15023–15063, https://doi.org/10.5194/acp-21-15023-2021, https://doi.org/10.5194/acp-21-15023-2021, 2021
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The Atmospheric Tomography Mission was an airborne study that mapped the chemical composition of the remote atmosphere. From this, we developed a comprehensive description of aerosol properties that provides a unique, global-scale dataset against which models can be compared. The data show the polluted nature of the remote atmosphere in the Northern Hemisphere and quantify the contributions of sea salt, dust, soot, biomass burning particles, and pollution particles to the haziness of the sky.
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.
Xuan Wang, Daniel J. Jacob, William Downs, Shuting Zhai, Lei Zhu, Viral Shah, Christopher D. Holmes, Tomás Sherwen, Becky Alexander, Mathew J. Evans, Sebastian D. Eastham, J. Andrew Neuman, Patrick R. Veres, Theodore K. Koenig, Rainer Volkamer, L. Gregory Huey, Thomas J. Bannan, Carl J. Percival, Ben H. Lee, and Joel A. Thornton
Atmos. Chem. Phys., 21, 13973–13996, https://doi.org/10.5194/acp-21-13973-2021, https://doi.org/10.5194/acp-21-13973-2021, 2021
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Halogen radicals have a broad range of implications for tropospheric chemistry, air quality, and climate. We present a new mechanistic description and comprehensive simulation of tropospheric halogens in a global 3-D model and compare the model results with surface and aircraft measurements. We find that halogen chemistry decreases the global tropospheric burden of ozone by 11 %, NOx by 6 %, and OH by 4 %.
Andreas Tilgner, Thomas Schaefer, Becky Alexander, Mary Barth, Jeffrey L. Collett Jr., Kathleen M. Fahey, Athanasios Nenes, Havala O. T. Pye, Hartmut Herrmann, and V. Faye McNeill
Atmos. Chem. Phys., 21, 13483–13536, https://doi.org/10.5194/acp-21-13483-2021, https://doi.org/10.5194/acp-21-13483-2021, 2021
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Feedbacks of acidity and atmospheric multiphase chemistry in deliquesced particles and clouds are crucial for the tropospheric composition, depositions, climate, and human health. This review synthesizes the current scientific knowledge on these feedbacks using both inorganic and organic aqueous-phase chemistry. Finally, this review outlines atmospheric implications and highlights the need for future investigations with respect to reducing emissions of key acid precursors in a changing world.
Zhuang Jiang, Becky Alexander, Joel Savarino, Joseph Erbland, and Lei Geng
The Cryosphere, 15, 4207–4220, https://doi.org/10.5194/tc-15-4207-2021, https://doi.org/10.5194/tc-15-4207-2021, 2021
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We used a snow photochemistry model (TRANSITS) to simulate the seasonal nitrate snow profile at Summit, Greenland. Comparisons between model outputs and observations suggest that at Summit post-depositional processing is active and probably dominates the snowpack δ15N seasonality. We also used the model to assess the degree of snow nitrate loss and the consequences in its isotopes at present and in the past, which helps for quantitative interpretations of ice-core nitrate records.
Cited articles
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Allan, B. J., McFiggans, G., Plane, J. M. C., and Coe, H.: Observations of iodine monoxide in the remote marine boundary layer, J. Geophys. Res., 105, 14363–14369, https://doi.org/10.1029/1999JD901188, 2000.
Ammann, M., Cox, R. A., Crowley, J. N., Jenkin, M. E., Mellouki, A., Rossi, M. J., Troe, J., and Wallington, T. J.: Evaluated kinetic and photochemical data for atmospheric chemistry: Volume VI – heterogeneous reactions with liquid substrates, Atmos. Chem. Phys., 13, 8045–8228, https://doi.org/10.5194/acp-13-8045-2013, 2013.
Andreae, M. O.: Emission of trace gases and aerosols from biomass burning – an updated assessment, Atmos. Chem. Phys., 19, 8523–8546, https://doi.org/10.5194/acp-19-8523-2019, 2019.
Angle, K. J., Crocker, D. R., Simpson, R. M. C., Mayer, K. J., Garofalo, L. A., Moore, A. N., Mora Garcia, S. L., Or, V. W., Srinivasan, S., Farhan, M., Sauer, J. S., Lee, C., Pothier, M. A., Farmer, D. K., Martz, T. R., Bertram, T. H., Cappa, C. D., Prather, K. A., and Grassian, V. H.: Acidity across the interface from the ocean surface to sea spray aerosol, Proc. Natl. Acad. Sci. USA, 118, e2018397118, https://doi.org/10.1073/pnas.2018397118, 2021.
Baccarini, A., Karlsson, L., Dommen, J., Duplessis, P., Vüllers, J., Brooks, I. M., Saiz-Lopez, A., Salter, M., Tjernström, M., Baltensperger, U., Zieger, P., and Schmale, J.: Frequent new particle formation over the high Arctic pack ice by enhanced iodine emissions, Nat. Commun., 11, 4924, https://doi.org/10.1038/s41467-020-18551-0, 2020.
Badia, A., Reeves, C. E., Baker, A. R., Saiz-Lopez, A., Volkamer, R., Koenig, T. K., Apel, E. C., Hornbrook, R. S., Carpenter, L. J., Andrews, S. J., Sherwen, T., and von Glasow, R.: Importance of reactive halogens in the tropical marine atmosphere: a regional modelling study using WRF-Chem, Atmos. Chem. Phys., 19, 3161–3189, https://doi.org/10.5194/acp-19-3161-2019, 2019.
Badia, A., Iglesias-Suarez, F., Fernandez, R. P., Cuevas, C. A., Kinnison, D. E., Lamarque, J., Griffiths, P. T., Tarasick, D. W., Liu, J., and Saiz-Lopez, A.: The Role of Natural Halogens in Global Tropospheric Ozone Chemistry and Budget Under Different 21st Century Climate Scenarios, J. GEOPHYS. RES. Atmospheres, 126, e2021JD034859, https://doi.org/10.1029/2021JD034859, 2021.
Baker, A. R.: Marine Aerosol Iodine Chemistry: The Importance of Soluble Organic Iodine, Environ. Chem., 2, 295, https://doi.org/10.1071/EN05070, 2005.
Baker, A. R. and Yodle, C.: Measurement report: Indirect evidence for the controlling influence of acidity on the speciation of iodine in Atlantic aerosols, Atmos. Chem. Phys., 21, 13067–13076, https://doi.org/10.5194/acp-21-13067-2021, 2021.
Baker, A. R., Thompson, D., Campos, M. L. A. M., Parry, S. J., and Jickells, T. D.: Iodine concentration and availability in atmospheric aerosol, Atmospheric Environment, 34, 4331–4336, https://doi.org/10.1016/S1352-2310(00)00208-9, 2000.
Baker, A. R., Tunnicliffe, C., and Jickells, T. D.: Iodine speciation and deposition fluxes from the marine atmosphere, J. Geophys. Res., 106, 28743–28749, https://doi.org/10.1029/2000JD000004, 2001.
Bates, K. H. and Jacob, D. J.: An Expanded Definition of the Odd Oxygen Family for Tropospheric Ozone Budgets: Implications for Ozone Lifetime and Stratospheric Influence, Geophysical Research Letters, 47, e2019GL084486, https://doi.org/10.1029/2019GL084486, 2020.
Beck, L. J., Sarnela, N., Junninen, H., Hoppe, C. J. M., Garmash, O., Bianchi, F., Riva, M., Rose, C., Peräkylä, O., Wimmer, D., Kausiala, O., Jokinen, T., Ahonen, L., Mikkilä, J., Hakala, J., He, X., Kontkanen, J., Wolf, K. K. E., Cappelletti, D., Mazzola, M., Traversi, R., Petroselli, C., Viola, A. P., Vitale, V., Lange, R., Massling, A., Nøjgaard, J. K., Krejci, R., Karlsson, L., Zieger, P., Jang, S., Lee, K., Vakkari, V., Lampilahti, J., Thakur, R. C., Leino, K., Kangasluoma, J., Duplissy, E., Siivola, E., Marbouti, M., Tham, Y. J., Saiz-Lopez, A., Petäjä, T., Ehn, M., Worsnop, D. R., Skov, H., Kulmala, M., Kerminen, V., and Sipilä, M.: Differing Mechanisms of New Particle Formation at Two Arctic Sites, Geophysical Research Letters, 48, e2020GL091334, https://doi.org/10.1029/2020GL091334, 2021.
Bell, N., Hsu, L., Jacob, D. J., Schultz, M. G., Blake, D. R., Butler, J. H., King, D. B., Lobert, J. M., and Maier-Reimer, E.: Methyl iodide: Atmospheric budget and use as a tracer of marine convection in global models, J. Geophys. Res., 107, https://doi.org/10.1029/2001JD001151, 2002.
Bey, I., Jacob, D. J., Yantosca, R. M., Logan, J. A., Field, B. D., Fiore, A. M., Li, Q., Liu, H. Y., Mickley, L. J., and Schultz, M. G.: Global modeling of tropospheric chemistry with assimilated meteorology: Model description and evaluation, J. Geophys. Res., 106, 23073–23095, https://doi.org/10.1029/2001JD000807, 2001.
Breider, T. J., Mickley, L. J., Jacob, D. J., Ge, C., Wang, J., Payer Sulprizio, M., Croft, B., Ridley, D. A., McConnell, J. R., Sharma, S., Husain, L., Dutkiewicz, V. A., Eleftheriadis, K., Skov, H., and Hopke, P. K.: Multidecadal trends in aerosol radiative forcing over the Arctic: Contribution of changes in anthropogenic aerosol to Arctic warming since 1980, J. GEOPHYS. RES. Atmospheres, 122, 3573–3594, https://doi.org/10.1002/2016JD025321, 2017.
Brown, L. V., Pound, R. J., Jones, M. R., Rowlinson, M. J., Chance, R., Jacobi, H.-W., Frey, M. M., Archer, S. D., Arndt, S., Barten, J. G. M., Blomquist, B. W., Dadic, R., Ganzeveld, L. N., Hannula, H.-R., Helmig, D., Jaggi, M., Krampe, D., Macfarlane, A. R., Miller, S., Schneebeli, M., and Carpenter, L. J.: Iodine speciation in snow during the MOSAiC expedition and its implications for Arctic iodine emissions, Faraday Discuss., 258, 441–472, https://doi.org/10.1039/d4fd00178h, 2025.
Butz, A., Bösch, H., Camy-Peyret, C., Chipperfield, M. P., Dorf, M., Kreycy, S., Kritten, L., Prados-Román, C., Schwärzle, J., and Pfeilsticker, K.: Constraints on inorganic gaseous iodine in the tropical upper troposphere and stratosphere inferred from balloon-borne solar occultation observations, Atmos. Chem. Phys., 9, 7229–7242, https://doi.org/10.5194/acp-9-7229-2009, 2009.
Carpenter, L. J., Hebestreit, K., Platt, U., and Liss, P. S.: Coastal zone production of IO precursors: a 2-dimensional study, Atmos. Chem. Phys., 1, 9–18, https://doi.org/10.5194/acp-1-9-2001, 2001.
Carpenter, L. J., MacDonald, S. M., Shaw, M. D., Kumar, R., Saunders, R. W., Parthipan, R., Wilson, J., and Plane, J. M. C.: Atmospheric iodine levels influenced by sea surface emissions of inorganic iodine, Nature Geosci., 6, 108–111, https://doi.org/10.1038/ngeo1687, 2013.
Carpenter, L. J., Chance, R. J., Sherwen, T., Adams, T. J., Ball, S. M., Evans, M. J., Hepach, H., Hollis, L. D. J., Hughes, C., Jickells, T. D., Mahajan, A., Stevens, D. P., Tinel, L., and Wadley, M. R.: Marine iodine emissions in a changing world, Proc. R. Soc. A, 477, 20200824, https://doi.org/10.1098/rspa.2020.0824, 2021.
Celli, G., Cairns, W. R. L., Scarchilli, C., Cuevas, C. A., Saiz-Lopez, A., Savarino, J., Stenni, B., Frezzotti, M., Becagli, S., Delmonte, B., Angot, H., Fernandez, R. P., and Spolaor, A.: Bromine, iodine and sodium along the EAIIST traverse: Bulk and surface snow latitudinal variability, Environmental Research, 239, 117344, https://doi.org/10.1016/j.envres.2023.117344, 2023.
Chance, R., Baker, A. R., Carpenter, L., and Jickells, T. D.: The distribution of iodide at the sea surface, Environ. Sci.: Processes Impacts, 16, 1841–1859, https://doi.org/10.1039/c4em00139g, 2014.
Corella, J. P., Maffezzoli, N., Spolaor, A., Vallelonga, P., Cuevas, C. A., Scoto, F., Müller, J., Vinther, B., Kjær, H. A., Cozzi, G., Edwards, R., Barbante, C., and Saiz-Lopez, A.: Climate changes modulated the history of Arctic iodine during the Last Glacial Cycle, Nat. Commun., 13, 88, https://doi.org/10.1038/s41467-021-27642-5, 2022.
Cuevas, C. A., Maffezzoli, N., Corella, J. P., Spolaor, A., Vallelonga, P., Kjær, H. A., Simonsen, M., Winstrup, M., Vinther, B., Horvat, C., Fernandez, R. P., Kinnison, D., Lamarque, J.-F., Barbante, C., and Saiz-Lopez, A.: Rapid increase in atmospheric iodine levels in the North Atlantic since the mid-20th century, Nat. Commun., 9, 1452, https://doi.org/10.1038/s41467-018-03756-1, 2018.
Deiber, G., George, Ch., Le Calvé, S., Schweitzer, F., and Mirabel, Ph.: Uptake study of ClONO2 and BrONO2 by Halide containing droplets, Atmos. Chem. Phys., 4, 1291–1299, https://doi.org/10.5194/acp-4-1291-2004, 2004.
Dix, B., Baidar, S., Bresch, J. F., Hall, S. R., Schmidt, K. S., Wang, S., and Volkamer, R.: Detection of iodine monoxide in the tropical free troposphere, Proc. Natl. Acad. Sci. USA, 110, 2035–2040, https://doi.org/10.1073/pnas.1212386110, 2013.
Droste, E. S., Baker, A. R., Yodle, C., Smith, A., and Ganzeveld, L.: Soluble Iodine Speciation in Marine Aerosols Across the Indian and Pacific Ocean Basins, Front. Mar. Sci., 8, 788105, https://doi.org/10.3389/fmars.2021.788105, 2021.
Eastham, S. D., Weisenstein, D. K., and Barrett, S. R. H.: Development and evaluation of the unified tropospheric–stratospheric chemistry extension (UCX) for the global chemistry-transport model GEOS-Chem, Atmospheric Environment, 89, 52–63, https://doi.org/10.1016/j.atmosenv.2014.02.001, 2014.
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Short summary
Global chemical transport models previously treated aerosols as a sink for reactive iodine (Iy); however, aerosol iodide is also a source of Iy via heterogeneous reactions involving hypohalous acids and halogen nitrates. We implemented this chemistry into GEOS-Chem, in addition to explicitly representing three aerosol iodine types: soluble organic iodine (SOI), iodide, and iodate. We found that aerosol recycling of iodide to form Iy is more than twice as fast as the other Iy sources combined.
Global chemical transport models previously treated aerosols as a sink for reactive iodine (Iy);...
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