Articles | Volume 24, issue 23
https://doi.org/10.5194/acp-24-13317-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
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https://doi.org/10.5194/acp-24-13317-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Opinion
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02 Dec 2024
Opinion | Highlight paper |
| 02 Dec 2024
| 02 Dec 2024
Opinion: Challenges and needs of tropospheric chemical mechanism development
Institute of Chemistry, University Clermont Auvergne, CNRS, 63000 Clermont-Ferrand, France
Wolfson Atmospheric Chemistry Laboratories, Department of Chemistry, University of York, Heslington, York, YO10 5DD, United Kingdom
National Centre for Atmospheric Science, University of York, Heslington, York, YO10 5DD, United Kingdom
Bernard Aumont
Univ Paris Est Créteil and Université Paris Cité, CNRS, LISA, 94010 Créteil, France
William P. L. Carter
College of Engineering Center for Environmental Research and Technology (CE-CERT), University of California, Riverside, CA 92521, USA
Max McGillen
Institut de Combustion, Aérothermique, Réactivité Environnement (ICARE), CNRS, 1C Avenue de la Recherche Scientifique, CEDEX 2, 45071 Orléans, France
Abdelwahid Mellouki
Institut de Combustion, Aérothermique, Réactivité Environnement (ICARE), CNRS, 1C Avenue de la Recherche Scientifique, CEDEX 2, 45071 Orléans, France
University Mohammed VI Polytechnic (UM6P), Lot 660, Hay Moulay Rachid Ben Guerir, 43150, Morocco
John Orlando
Atmospheric Chemistry Observations and Modeling Lab, National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO 80307, USA
Bénédicte Picquet-Varrault
Univ Paris Est Créteil and Université Paris Cité, CNRS, LISA, 94010 Créteil, France
Paul Seakins
School of Chemistry, University of Leeds, Leeds, LS2 9JT, United Kingdom
William R. Stockwell
Department of Physics, University of Texas at El Paso, El Paso, TX, USA
Luc Vereecken
Institute of Climate and Energy Systems ICE-3: Troposphere, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
Timothy J. Wallington
Center for Sustainable Systems, School for Environment and Sustainability, University of Michigan, Ann Arbor MI 48109, USA
Related authors
Barbara Ervens, Ken S. Carslaw, Thomas Koop, and Ulrich Pöschl
EGUsphere, https://doi.org/10.5194/egusphere-2025-419, https://doi.org/10.5194/egusphere-2025-419, 2025
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
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Over the past two decades, the European Geosciences Union (EGU) has demonstrated the success, viability and benefits of interactive open access (OA) publishing with public peer review in its journals, its publishing platform EGUsphere and virtual compilations. The article summarizes the evolution of the EGU/Copernicus publications and of OA publishing with interactive public peer review at large by placing the EGU/Copernicus publications in the context of current and future global open science.
This article is included in the Encyclopedia of Geosciences
Barbara Ervens, Pierre Amato, Kifle Aregahegn, Muriel Joly, Amina Khaled, Tiphaine Labed-Veydert, Frédéric Mathonat, Leslie Nuñez López, Raphaëlle Péguilhan, and Minghui Zhang
Biogeosciences, 22, 243–256, https://doi.org/10.5194/bg-22-243-2025, https://doi.org/10.5194/bg-22-243-2025, 2025
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Atmospheric microorganisms are a small fraction of Earth's microbiome, with bacteria being a significant part. Aerosolized bacteria are airborne for a few days, encountering unique chemical and physical conditions affecting stress levels and survival. We explore chemical and microphysical conditions bacteria encounter, highlighting potential nutrient and oxidant limitations and diverse effects by pollutants, which may ultimately impact the microbiome's role in global ecosystems and biodiversity.
This article is included in the Encyclopedia of Geosciences
Raphaëlle Péguilhan, Florent Rossi, Muriel Joly, Engy Nasr, Bérénice Batut, François Enault, Barbara Ervens, and Pierre Amato
EGUsphere, https://doi.org/10.5194/egusphere-2024-2338, https://doi.org/10.5194/egusphere-2024-2338, 2024
Short summary
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Using comparative metagenomics/metatranscriptomics, we examined the functioning of airborne microorganisms in clouds and clear atmosphere; clouds are atmospheric volumes where multiple microbial processes are promoted compared with clear atmosphere; Overrepresented microbial functions of interest include the processing of chemical compounds, biomass production and the regulation of oxidants; - this has implications for biogeochemical cycles and microbial ecology.
This article is included in the Encyclopedia of Geosciences
Leslie Nuñez López, Pierre Amato, and Barbara Ervens
Atmos. Chem. Phys., 24, 5181–5198, https://doi.org/10.5194/acp-24-5181-2024, https://doi.org/10.5194/acp-24-5181-2024, 2024
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Living bacteria comprise a small particle fraction in the atmosphere. Our model study shows that atmospheric bacteria in clouds may efficiently biodegrade formic and acetic acids that affect the acidity of rain. We conclude that current atmospheric models underestimate losses of these acids as they only consider chemical processes. We suggest that biodegradation can affect atmospheric concentration not only of formic and acetic acids but also of other volatile, moderately soluble organics.
This article is included in the Encyclopedia of Geosciences
Amina Khaled, Minghui Zhang, and Barbara Ervens
Atmos. Chem. Phys., 22, 1989–2009, https://doi.org/10.5194/acp-22-1989-2022, https://doi.org/10.5194/acp-22-1989-2022, 2022
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Chemical reactions with iron in clouds and aerosol form and cycle reactive oxygen species (ROS). Previous model studies assumed that all cloud droplets (particles) contain iron, while single-particle analyses showed otherwise. By means of a model, we explore the bias in predicted ROS budgets by distributing a given iron mass to either all or only a few droplets (particles). Implications for oxidation potential, radical loss and iron oxidation state are discussed.
This article is included in the Encyclopedia of Geosciences
Ramon Campos Braga, Barbara Ervens, Daniel Rosenfeld, Meinrat O. Andreae, Jan-David Förster, Daniel Fütterer, Lianet Hernández Pardo, Bruna A. Holanda, Tina Jurkat-Witschas, Ovid O. Krüger, Oliver Lauer, Luiz A. T. Machado, Christopher Pöhlker, Daniel Sauer, Christiane Voigt, Adrian Walser, Manfred Wendisch, Ulrich Pöschl, and Mira L. Pöhlker
Atmos. Chem. Phys., 21, 17513–17528, https://doi.org/10.5194/acp-21-17513-2021, https://doi.org/10.5194/acp-21-17513-2021, 2021
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Interactions of aerosol particles with clouds represent a large uncertainty in estimates of climate change. Properties of aerosol particles control their ability to act as cloud condensation nuclei. Using aerosol measurements in the Amazon, we performed model studies to compare predicted and measured cloud droplet number concentrations at cloud bases. Our results confirm previous estimates of particle hygroscopicity in this region.
This article is included in the Encyclopedia of Geosciences
Ramon Campos Braga, Daniel Rosenfeld, Ovid O. Krüger, Barbara Ervens, Bruna A. Holanda, Manfred Wendisch, Trismono Krisna, Ulrich Pöschl, Meinrat O. Andreae, Christiane Voigt, and Mira L. Pöhlker
Atmos. Chem. Phys., 21, 14079–14088, https://doi.org/10.5194/acp-21-14079-2021, https://doi.org/10.5194/acp-21-14079-2021, 2021
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Quantifying the precipitation within clouds is crucial for our understanding of the Earth's hydrological cycle. Using in situ measurements of cloud and rain properties over the Amazon Basin and Atlantic Ocean, we show here a linear relationship between the effective radius (re) and precipitation water content near the tops of convective clouds for different pollution states and temperature levels. Our results emphasize the role of re to determine both initiation and amount of precipitation.
This article is included in the Encyclopedia of Geosciences
Mira L. Pöhlker, Minghui Zhang, Ramon Campos Braga, Ovid O. Krüger, Ulrich Pöschl, and Barbara Ervens
Atmos. Chem. Phys., 21, 11723–11740, https://doi.org/10.5194/acp-21-11723-2021, https://doi.org/10.5194/acp-21-11723-2021, 2021
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Clouds cool our atmosphere. The role of small aerosol particles in affecting them represents one of the largest uncertainties in current estimates of climate change. Traditionally it is assumed that cloud droplets only form particles of diameters ~ 100 nm (
This article is included in the Encyclopedia of Geosciences
accumulation mode). Previous studies suggest that this can also occur in smaller particles (
Aitken mode). Our study provides a general framework to estimate under which aerosol and cloud conditions Aitken mode particles affect clouds.
Minghui Zhang, Amina Khaled, Pierre Amato, Anne-Marie Delort, and Barbara Ervens
Atmos. Chem. Phys., 21, 3699–3724, https://doi.org/10.5194/acp-21-3699-2021, https://doi.org/10.5194/acp-21-3699-2021, 2021
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Although primary biological aerosol particles (PBAPs, bioaerosols) represent a small fraction of total atmospheric aerosol burden, they might affect climate and public health. We summarize which PBAP properties are important to affect their inclusion in clouds and interaction with light and might also affect their residence time and transport in the atmosphere. Our study highlights that not only chemical and physical but also biological processes can modify these physicochemical properties.
This article is included in the Encyclopedia of Geosciences
Amina Khaled, Minghui Zhang, Pierre Amato, Anne-Marie Delort, and Barbara Ervens
Atmos. Chem. Phys., 21, 3123–3141, https://doi.org/10.5194/acp-21-3123-2021, https://doi.org/10.5194/acp-21-3123-2021, 2021
Saly Jaber, Muriel Joly, Maxence Brissy, Martin Leremboure, Amina Khaled, Barbara Ervens, and Anne-Marie Delort
Biogeosciences, 18, 1067–1080, https://doi.org/10.5194/bg-18-1067-2021, https://doi.org/10.5194/bg-18-1067-2021, 2021
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Our study is of interest to atmospheric scientists and environmental microbiologists, as we show that clouds can be considered a medium where bacteria efficiently degrade and transform amino acids, in competition with chemical processes. As current atmospheric multiphase models are restricted to chemical degradation of organic compounds, our conclusions motivate further model development.
This article is included in the Encyclopedia of Geosciences
Saly Jaber, Audrey Lallement, Martine Sancelme, Martin Leremboure, Gilles Mailhot, Barbara Ervens, and Anne-Marie Delort
Atmos. Chem. Phys., 20, 4987–4997, https://doi.org/10.5194/acp-20-4987-2020, https://doi.org/10.5194/acp-20-4987-2020, 2020
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Current atmospheric multiphase models do not include biotransformations of organic compounds by bacteria, although many previous studies of our and other research groups have shown microbial activity in cloud water. The current lab/model study shows that for water-soluble aromatic compounds, biodegradation by bacteria may be as efficient as chemical reactions in cloud water.
This article is included in the Encyclopedia of Geosciences
Barbara Ervens and Pierre Amato
Atmos. Chem. Phys., 20, 1777–1794, https://doi.org/10.5194/acp-20-1777-2020, https://doi.org/10.5194/acp-20-1777-2020, 2020
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Bacteria in the atmosphere are important due to their potential adverse health effects and as initiators of ice cloud formation. Observational studies suggest that bacterial cells grow and multiply in clouds and also consume organic compounds.
We estimate the role of microbial processes in the atmosphere for (i) the increase in biological aerosol mass by cell growth and multiplication and (ii) the sink strength of organics in clouds as a loss process in addition to chemical reactions.
This article is included in the Encyclopedia of Geosciences
Barbara Ervens, Armin Sorooshian, Abdulmonam M. Aldhaif, Taylor Shingler, Ewan Crosbie, Luke Ziemba, Pedro Campuzano-Jost, Jose L. Jimenez, and Armin Wisthaler
Atmos. Chem. Phys., 18, 16099–16119, https://doi.org/10.5194/acp-18-16099-2018, https://doi.org/10.5194/acp-18-16099-2018, 2018
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The paper presents a new framework that can be used to identify emission scenarios in which aerosol populations are most likely modified by chemical processes in clouds. We show that in neither very polluted nor in very clean air masses is this the case. Only if the ratio of possible aerosol mass precursors (sulfur dioxide, some organics) and preexisting aerosol mass is sufficiently high will aerosol particles show substantially modified physicochemical properties upon cloud processing.
This article is included in the Encyclopedia of Geosciences
B. Ervens, P. Renard, S. Tlili, S. Ravier, J.-L. Clément, and A. Monod
Atmos. Chem. Phys., 15, 9109–9127, https://doi.org/10.5194/acp-15-9109-2015, https://doi.org/10.5194/acp-15-9109-2015, 2015
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A detailed chemical mechanism is developed based on laboratory studies that predicts the formation of high molecular weight compounds in the aqueous phase of atmospheric aerosol particles. Model simulations using this mechanism for atmospheric conditions show that these pathways are likely not a substantial source of particle mass, unless unidentified precursors for these compounds exist that were not taken into account so far and/or the solubility of oxygen in aerosol water is overestimated.
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B. Yuan, P. R. Veres, C. Warneke, J. M. Roberts, J. B. Gilman, A. Koss, P. M. Edwards, M. Graus, W. C. Kuster, S.-M. Li, R. J. Wild, S. S. Brown, W. P. Dubé, B. M. Lerner, E. J. Williams, J. E. Johnson, P. K. Quinn, T. S. Bates, B. Lefer, P. L. Hayes, J. L. Jimenez, R. J. Weber, R. Zamora, B. Ervens, D. B. Millet, B. Rappenglück, and J. A. de Gouw
Atmos. Chem. Phys., 15, 1975–1993, https://doi.org/10.5194/acp-15-1975-2015, https://doi.org/10.5194/acp-15-1975-2015, 2015
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In this work, secondary formation of formic acid at an urban site and a site in an oil and gas production region is studied. We investigated various gas phase formation pathways of formic acid, including those recently proposed, using a box model. The contributions from aerosol-related processes, fog events and air-snow exchange to formic acid are also quantified.
This article is included in the Encyclopedia of Geosciences
B. Ervens, Y. Wang, J. Eagar, W. R. Leaitch, A. M. Macdonald, K. T. Valsaraj, and P. Herckes
Atmos. Chem. Phys., 13, 5117–5135, https://doi.org/10.5194/acp-13-5117-2013, https://doi.org/10.5194/acp-13-5117-2013, 2013
Barbara Ervens, Ken S. Carslaw, Thomas Koop, and Ulrich Pöschl
EGUsphere, https://doi.org/10.5194/egusphere-2025-419, https://doi.org/10.5194/egusphere-2025-419, 2025
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
Over the past two decades, the European Geosciences Union (EGU) has demonstrated the success, viability and benefits of interactive open access (OA) publishing with public peer review in its journals, its publishing platform EGUsphere and virtual compilations. The article summarizes the evolution of the EGU/Copernicus publications and of OA publishing with interactive public peer review at large by placing the EGU/Copernicus publications in the context of current and future global open science.
This article is included in the Encyclopedia of Geosciences
Barbara Ervens, Pierre Amato, Kifle Aregahegn, Muriel Joly, Amina Khaled, Tiphaine Labed-Veydert, Frédéric Mathonat, Leslie Nuñez López, Raphaëlle Péguilhan, and Minghui Zhang
Biogeosciences, 22, 243–256, https://doi.org/10.5194/bg-22-243-2025, https://doi.org/10.5194/bg-22-243-2025, 2025
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Atmospheric microorganisms are a small fraction of Earth's microbiome, with bacteria being a significant part. Aerosolized bacteria are airborne for a few days, encountering unique chemical and physical conditions affecting stress levels and survival. We explore chemical and microphysical conditions bacteria encounter, highlighting potential nutrient and oxidant limitations and diverse effects by pollutants, which may ultimately impact the microbiome's role in global ecosystems and biodiversity.
This article is included in the Encyclopedia of Geosciences
William P. L. Carter, Jia Jiang, John J. Orlando, and Kelley C. Barsanti
Atmos. Chem. Phys., 25, 199–242, https://doi.org/10.5194/acp-25-199-2025, https://doi.org/10.5194/acp-25-199-2025, 2025
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This paper describes the scientific basis for gas-phase atmospheric chemical mechanisms derived using the SAPRC mechanism generation system, MechGen. It can derive mechanisms for most organic compounds with C, H, O, or N atoms, including initial reactions of organics with OH, O3, NO3, and O3P or by photolysis, as well as the reactions of the various types of intermediates that are formed. The paper includes a description of areas of uncertainty where additional research and updates are needed.
This article is included in the Encyclopedia of Geosciences
Christopher Lawrence, Mary Barth, John Orlando, Paul Casson, Richard Brandt, Daniel Kelting, Elizabeth Yerger, and Sara Lance
Atmos. Chem. Phys., 24, 13693–13713, https://doi.org/10.5194/acp-24-13693-2024, https://doi.org/10.5194/acp-24-13693-2024, 2024
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This work uses chemical transport and box modeling to study the gas- and aqueous-phase production of organic acid concentrations measured in cloud water at the summit of Whiteface Mountain on 1 July 2018. Isoprene was the major source of formic, acetic, and oxalic acid. Gas-phase chemistry greatly underestimated formic and acetic acid, indicating missing sources, while cloud chemistry was a key source of oxalic acid. More studies of organic acids are required to better constrain their sources.
This article is included in the Encyclopedia of Geosciences
Simone T. Andersen, Rolf Sander, Patrick Dewald, Laura Wüst, Tobias Seubert, Gunther N. T. E. Türk, Jan Schuladen, Max R. McGillen, Chaoyang Xue, Abdelwahid Mellouki, Alexandre Kukui, Vincent Michoud, Manuela Cirtog, Mathieu Cazaunau, Astrid Bauville, Hichem Bouzidi, Paola Formenti, Cyrielle Denjean, Jean-Claude Etienne, Olivier Garrouste, Christopher Cantrell, Jos Lelieveld, and John N. Crowley
EGUsphere, https://doi.org/10.5194/egusphere-2024-3437, https://doi.org/10.5194/egusphere-2024-3437, 2024
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Measurements and modelling of reactive nitrogen gases observed in a suburban temperate forest in Rambouillet, France circa 50 km southwest of Paris in 2022 indicate that the biosphere rapidly scavenges organic nitrates of mixed biogenic and anthropogenic origin, resulting in short lifetimes for e.g. alkyl nitrates and peroxy nitrates.
This article is included in the Encyclopedia of Geosciences
Lauri Franzon, Marie Camredon, Richard Valorso, Bernard Aumont, and Theo Kurtén
Atmos. Chem. Phys., 24, 11679–11699, https://doi.org/10.5194/acp-24-11679-2024, https://doi.org/10.5194/acp-24-11679-2024, 2024
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In this article we investigate the formation of large, sticky molecules from various organic compounds entering the atmosphere as primary emissions and the degree to which these processes may contribute to organic aerosol particle mass. More specifically, we qualitatively investigate a recently discovered chemical reaction channel for one of the most important short-lived radical compounds, peroxy radicals, and discover which of these reactions are most atmospherically important.
This article is included in the Encyclopedia of Geosciences
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.
This article is included in the Encyclopedia of Geosciences
Raphaëlle Péguilhan, Florent Rossi, Muriel Joly, Engy Nasr, Bérénice Batut, François Enault, Barbara Ervens, and Pierre Amato
EGUsphere, https://doi.org/10.5194/egusphere-2024-2338, https://doi.org/10.5194/egusphere-2024-2338, 2024
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Using comparative metagenomics/metatranscriptomics, we examined the functioning of airborne microorganisms in clouds and clear atmosphere; clouds are atmospheric volumes where multiple microbial processes are promoted compared with clear atmosphere; Overrepresented microbial functions of interest include the processing of chemical compounds, biomass production and the regulation of oxidants; - this has implications for biogeochemical cycles and microbial ecology.
This article is included in the Encyclopedia of Geosciences
Rhianna Louise Evans, Daniel Jack Bryant, Aristeidis Voliotis, Dawei Hu, Huihui Wu, Sara Aisyah Syafira, Osayomwanbor Ebenezer Oghama, Gordon McFiggans, Jacqueline Fiona Hamilton, and Andrew Robert Rickard
EGUsphere, https://doi.org/10.5194/egusphere-2024-2642, https://doi.org/10.5194/egusphere-2024-2642, 2024
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The chemical composition of organic aerosol derived from wood burning emissions under different burning conditions was characterised. Fresh emissions from flaming and smouldering were largely aromatic in nature whereas upon aging the aromatic content decreased. This decrease was greater for smouldering due to the loss of toxic polyaromatic species. Whereas under flaming conditions highly toxic polyaromatic species were produced. These differences present an important challenge for policy.
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Beth S. Nelson, Zhenze Liu, Freya A. Squires, Marvin Shaw, James R. Hopkins, Jacqueline F. Hamilton, Andrew R. Rickard, Alastair C. Lewis, Zongbo Shi, and James D. Lee
Atmos. Chem. Phys., 24, 9031–9044, https://doi.org/10.5194/acp-24-9031-2024, https://doi.org/10.5194/acp-24-9031-2024, 2024
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The impact of combined air quality and carbon neutrality policies on O3 formation in Beijing was investigated. Emissions inventory data were used to estimate future pollutant mixing ratios relative to ground-level observations. O3 production was found to be most sensitive to changes in alkenes, but large reductions in less reactive compounds led to larger reductions in future O3 production. This study highlights the importance of understanding the emissions of organic pollutants.
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Patrick Dewald, Tobias Seubert, Simone T. Andersen, Gunther N. T. E. Türk, Jan Schuladen, Max R. McGillen, 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, Chaoyang Xue, Abdelwahid Mellouki, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 24, 8983–8997, https://doi.org/10.5194/acp-24-8983-2024, https://doi.org/10.5194/acp-24-8983-2024, 2024
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In the scope of a field campaign in a suburban forest near Paris in the summer of 2022, we measured the reactivity of the nitrate radical NO3 towards biogenic volatile organic compounds (BVOCs; e.g. monoterpenes) mainly below but also above the canopy. NO3 reactivity was the highest during nights with strong temperature inversions and decreased strongly with height. Reactions with BVOCs were the main removal process of NO3 throughout the diel cycle below the canopy.
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David P. Edwards, Sara Martínez-Alonso, Duseong S. Jo, Ivan Ortega, Louisa K. Emmons, John J. Orlando, Helen M. Worden, Jhoon Kim, Hanlim Lee, Junsung Park, and Hyunkee Hong
Atmos. Chem. Phys., 24, 8943–8961, https://doi.org/10.5194/acp-24-8943-2024, https://doi.org/10.5194/acp-24-8943-2024, 2024
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Until recently, satellite observations of atmospheric pollutants at any location could only be obtained once a day. New geostationary satellites stare at a region of the Earth to make hourly measurements, and the Geostationary Environment Monitoring Spectrometer is the first looking at Asia. These data and model simulations show how the change seen for one important pollutant that determines air quality depends on a combination of pollution emissions, atmospheric chemistry, and meteorology.
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Tommaso Galeazzo, Bernard Aumont, Marie Camredon, Richard Valorso, Yong B. Lim, Paul J. Ziemann, and Manabu Shiraiwa
Atmos. Chem. Phys., 24, 5549–5565, https://doi.org/10.5194/acp-24-5549-2024, https://doi.org/10.5194/acp-24-5549-2024, 2024
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Secondary organic aerosol (SOA) derived from n-alkanes is a major component of anthropogenic particulate matter. We provide an analysis of n-alkane SOA by chemistry modeling, machine learning, and laboratory experiments, showing that n-alkane SOA adopts low-viscous semi-solid or liquid states. Our results indicate few kinetic limitations of mass accommodation in SOA formation, supporting the application of equilibrium partitioning for simulating n-alkane SOA in large-scale atmospheric models.
This article is included in the Encyclopedia of Geosciences
Leslie Nuñez López, Pierre Amato, and Barbara Ervens
Atmos. Chem. Phys., 24, 5181–5198, https://doi.org/10.5194/acp-24-5181-2024, https://doi.org/10.5194/acp-24-5181-2024, 2024
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Living bacteria comprise a small particle fraction in the atmosphere. Our model study shows that atmospheric bacteria in clouds may efficiently biodegrade formic and acetic acids that affect the acidity of rain. We conclude that current atmospheric models underestimate losses of these acids as they only consider chemical processes. We suggest that biodegradation can affect atmospheric concentration not only of formic and acetic acids but also of other volatile, moderately soluble organics.
This article is included in the Encyclopedia of Geosciences
Ernst-Peter Röth and Luc Vereecken
Atmos. Chem. Phys., 24, 2625–2638, https://doi.org/10.5194/acp-24-2625-2024, https://doi.org/10.5194/acp-24-2625-2024, 2024
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The paper presents the radical and molecular product quantum yields in the photolysis reaction of CHDO at wavelengths above 300 nm. Two different approaches based on literature data are used, with results falling within both approaches' uncertainty ranges. Simple functional forms are presented for use in photochemical models of the atmosphere.
This article is included in the Encyclopedia of Geosciences
Frank A. F. Winiberg, William J. Warman, Charlotte A. Brumby, Graham Boustead, Iustinian G. Bejan, Thomas H. Speak, Dwayne E. Heard, Daniel Stone, and Paul W. Seakins
Atmos. Meas. Tech., 16, 4375–4390, https://doi.org/10.5194/amt-16-4375-2023, https://doi.org/10.5194/amt-16-4375-2023, 2023
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OH and HO2 are key reactive intermediates in the Earth's atmosphere. Accurate measurements in either the field or simulation chambers provide a good test for chemical mechanisms. Fluorescence techniques have the appropriate sensitivity for detection but require calibration. This paper compares different methods of calibration and specifically how calibration factors vary across a temperature range relevant to atmospheric and chamber determinations.
This article is included in the Encyclopedia of Geosciences
Bryan K. Place, William T. Hutzell, K. Wyat Appel, Sara Farrell, Lukas Valin, Benjamin N. Murphy, Karl M. Seltzer, Golam Sarwar, Christine Allen, Ivan R. Piletic, Emma L. D'Ambro, Emily Saunders, Heather Simon, Ana Torres-Vasquez, Jonathan Pleim, Rebecca H. Schwantes, Matthew M. Coggon, Lu Xu, William R. Stockwell, and Havala O. T. Pye
Atmos. Chem. Phys., 23, 9173–9190, https://doi.org/10.5194/acp-23-9173-2023, https://doi.org/10.5194/acp-23-9173-2023, 2023
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Ground-level ozone is a pollutant with adverse human health and ecosystem effects. Air quality models allow scientists to understand the chemical production of ozone and demonstrate impacts of air quality management plans. In this work, the role of multiple systems in ozone production was investigated for the northeastern US in summer. Model updates to chemical reaction rates and monoterpene chemistry were most influential in decreasing predicted ozone and improving agreement with observations.
This article is included in the Encyclopedia of Geosciences
Caterina Mapelli, James K. Donnelly, Úna E. Hogan, Andrew R. Rickard, Abbie T. Robinson, Fergal Byrne, Con Rob McElroy, Basile F. E. Curchod, Daniel Hollas, and Terry J. Dillon
Atmos. Chem. Phys., 23, 7767–7779, https://doi.org/10.5194/acp-23-7767-2023, https://doi.org/10.5194/acp-23-7767-2023, 2023
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Solvents are chemical compounds with countless uses in the chemical industry, and they also represent one of the main sources of pollution in the chemical sector. Scientists are trying to develop new
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greensafer solvents which present favourable advantages when compared to traditional solvents. Since the assessment of these green solvents often lacks air quality considerations, this study aims to understand the behaviour of these compounds, investigating their reactivity in the troposphere.
Hao Luo, Luc Vereecken, Hongru Shen, Sungah Kang, Iida Pullinen, Mattias Hallquist, Hendrik Fuchs, Andreas Wahner, Astrid Kiendler-Scharr, Thomas F. Mentel, and Defeng Zhao
Atmos. Chem. Phys., 23, 7297–7319, https://doi.org/10.5194/acp-23-7297-2023, https://doi.org/10.5194/acp-23-7297-2023, 2023
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Oxidation of limonene, an element emitted by trees and chemical products, by OH, a daytime oxidant, forms many highly oxygenated organic molecules (HOMs), including C10-20 compounds. HOMs play an important role in new particle formation and growth. HOM formation can be explained by the chemistry of peroxy radicals. We found that a minor branching ratio initial pathway plays an unexpected, significant role. Considering this pathway enables accurate simulations of HOMs and other concentrations.
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Havala O. T. Pye, Bryan K. Place, Benjamin N. Murphy, Karl M. Seltzer, Emma L. D'Ambro, Christine Allen, Ivan R. Piletic, Sara Farrell, Rebecca H. Schwantes, Matthew M. Coggon, Emily Saunders, Lu Xu, Golam Sarwar, William T. Hutzell, Kristen M. Foley, George Pouliot, Jesse Bash, and William R. Stockwell
Atmos. Chem. Phys., 23, 5043–5099, https://doi.org/10.5194/acp-23-5043-2023, https://doi.org/10.5194/acp-23-5043-2023, 2023
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Chemical mechanisms describe how emissions from vehicles, vegetation, and other sources are chemically transformed in the atmosphere to secondary products including criteria and hazardous air pollutants. The Community Regional Atmospheric Chemistry Multiphase Mechanism integrates gas-phase radical chemistry with pathways to fine-particle mass. New species were implemented, resulting in a bottom-up representation of organic aerosol, which is required for accurate source attribution of pollutants.
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Philip T. M. Carlsson, Luc Vereecken, Anna Novelli, François Bernard, Steven S. Brown, Bellamy Brownwood, Changmin Cho, John N. Crowley, Patrick Dewald, Peter M. Edwards, Nils Friedrich, Juliane L. Fry, Mattias Hallquist, Luisa Hantschke, Thorsten Hohaus, Sungah Kang, Jonathan Liebmann, Alfred W. Mayhew, Thomas Mentel, David Reimer, Franz Rohrer, Justin Shenolikar, Ralf Tillmann, Epameinondas Tsiligiannis, Rongrong Wu, Andreas Wahner, Astrid Kiendler-Scharr, and Hendrik Fuchs
Atmos. Chem. Phys., 23, 3147–3180, https://doi.org/10.5194/acp-23-3147-2023, https://doi.org/10.5194/acp-23-3147-2023, 2023
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The investigation of the night-time oxidation of the most abundant hydrocarbon, isoprene, in chamber experiments shows the importance of reaction pathways leading to epoxy products, which could enhance particle formation, that have so far not been accounted for. The chemical lifetime of organic nitrates from isoprene is long enough for the majority to be further oxidized the next day by daytime oxidants.
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Nakul N. Karle, Ricardo K. Sakai, Rosa M. Fitzgerald, Charles Ichoku, Fernando Mercado, and William R. Stockwell
Atmos. Meas. Tech., 16, 1073–1085, https://doi.org/10.5194/amt-16-1073-2023, https://doi.org/10.5194/amt-16-1073-2023, 2023
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Extensive virga research is uncommon, even though it is a common phenomenon. A systematic method was developed to characterize virga using available datasets. In total, 50 virga events were observed, appearing only during a specific time of the year, revealing a seasonal pattern. These virga events were identified and classified, and their impact on surface PM measurements was investigated. A more detailed examination of the selected events reveals that virga impacts regional air quality.
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Daniel J. Bryant, Beth S. Nelson, Stefan J. Swift, Sri Hapsari Budisulistiorini, Will S. Drysdale, Adam R. Vaughan, Mike J. Newland, James R. Hopkins, James M. Cash, Ben Langford, Eiko Nemitz, W. Joe F. Acton, C. Nicholas Hewitt, Tuhin Mandal, Bhola R. Gurjar, Shivani, Ranu Gadi, James D. Lee, Andrew R. Rickard, and Jacqueline F. Hamilton
Atmos. Chem. Phys., 23, 61–83, https://doi.org/10.5194/acp-23-61-2023, https://doi.org/10.5194/acp-23-61-2023, 2023
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This paper investigates the sources of isoprene and monoterpene compounds and their particulate-phase oxidation products in Delhi, India. This was done to improve our understanding of the sources, concentrations, and fate of volatile emissions in megacities. By studying the chemical composition of offline filter samples, we report that a significant share of the oxidised organic aerosol in Delhi is from isoprene and monoterpenes. This has implications for human health and policy development.
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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.
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Yindong Guo, Hongru Shen, Iida Pullinen, Hao Luo, Sungah Kang, Luc Vereecken, Hendrik Fuchs, Mattias Hallquist, Ismail-Hakki Acir, Ralf Tillmann, Franz Rohrer, Jürgen Wildt, Astrid Kiendler-Scharr, Andreas Wahner, Defeng Zhao, and Thomas F. Mentel
Atmos. Chem. Phys., 22, 11323–11346, https://doi.org/10.5194/acp-22-11323-2022, https://doi.org/10.5194/acp-22-11323-2022, 2022
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The oxidation of limonene, a common volatile emitted by trees and chemical products, by NO3, a nighttime oxidant, forms many highly oxygenated organic molecules (HOM), including C10-30 compounds. Most of the HOM are second-generation organic nitrates, in which carbonyl-substituted C10 nitrates accounted for a major fraction. Their formation can be explained by chemistry of peroxy radicals. HOM, especially low-volatile ones, play an important role in nighttime new particle formation and growth.
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Emily B. Franklin, Lindsay D. Yee, Bernard Aumont, Robert J. Weber, Paul Grigas, and Allen H. Goldstein
Atmos. Meas. Tech., 15, 3779–3803, https://doi.org/10.5194/amt-15-3779-2022, https://doi.org/10.5194/amt-15-3779-2022, 2022
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The composition of atmospheric aerosols are extremely complex, containing hundreds of thousands of estimated individual compounds. The majority of these compounds have never been catalogued in widely used databases, making them extremely difficult for atmospheric chemists to identify and analyze. In this work, we present Ch3MS-RF, a machine-learning-based model to enable characterization of complex mixtures and prediction of structure-specific properties of unidentifiable organic compounds.
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Mike J. Newland, Camille Mouchel-Vallon, Richard Valorso, Bernard Aumont, Luc Vereecken, Michael E. Jenkin, and Andrew R. Rickard
Atmos. Chem. Phys., 22, 6167–6195, https://doi.org/10.5194/acp-22-6167-2022, https://doi.org/10.5194/acp-22-6167-2022, 2022
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Alkene ozonolysis produces Criegee intermediates, which can act as oxidants or decompose to give a range of closed-shell and radical products, including OH. Therefore it is essential to accurately represent the chemistry of Criegee intermediates in atmospheric models in order to understand their impacts on atmospheric composition. Here we provide a mechanism construction protocol by which the central features of alkene ozonolysis chemistry can be included in an automatic mechanism generator.
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Zara S. Mir, Matthew Jamieson, Nicholas R. Greenall, Paul W. Seakins, Mark A. Blitz, and Daniel Stone
Atmos. Meas. Tech., 15, 2875–2887, https://doi.org/10.5194/amt-15-2875-2022, https://doi.org/10.5194/amt-15-2875-2022, 2022
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In this work we describe the development and characterisation of an experiment using laser flash photolysis coupled with time-resolved mid-infrared (mid-IR) quantum cascade laser (QCL) absorption spectroscopy, with initial results reported for measurements of the infrared spectrum, kinetics, and product yields for the reaction of the CH2OO Criegee intermediate with SO2. This work has significance for the identification and measurement of reactive trace species in complex systems.
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Lucien Froidevaux, Douglas E. Kinnison, Michelle L. Santee, Luis F. Millán, Nathaniel J. Livesey, William G. Read, Charles G. Bardeen, John J. Orlando, and Ryan A. Fuller
Atmos. Chem. Phys., 22, 4779–4799, https://doi.org/10.5194/acp-22-4779-2022, https://doi.org/10.5194/acp-22-4779-2022, 2022
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We analyze satellite-derived distributions of chlorine monoxide (ClO) and hypochlorous acid (HOCl) in the upper atmosphere. For 2005–2020, from 50°S to 50°N and over ~30 to 45 km, ClO and HOCl decreased by −0.7 % and −0.4 % per year, respectively. A detailed model of chemistry and dynamics agrees with the results. These decreases confirm the effectiveness of the 1987 Montreal Protocol, which limited emissions of chlorine- and bromine-containing source gases, in order to protect the ozone layer.
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Chaoyang Xue, Can Ye, Jörg Kleffmann, Chenglong Zhang, Valéry Catoire, Fengxia Bao, Abdelwahid Mellouki, Likun Xue, Jianmin Chen, Keding Lu, Yong Zhao, Hengde Liu, Zhaoxin Guo, and Yujing Mu
Atmos. Chem. Phys., 22, 3149–3167, https://doi.org/10.5194/acp-22-3149-2022, https://doi.org/10.5194/acp-22-3149-2022, 2022
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Summertime measurements of nitrous acid (HONO) and related parameters were conducted at the foot and the summit of Mt. Tai (1534 m above sea level). We proposed a rapid vertical air mass exchange between the foot and the summit level, which enhances the role of HONO in the oxidizing capacity of the upper boundary layer. Kinetics for aerosol-derived HONO sources were constrained. HONO formation from different paths was quantified and discussed.
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Amina Khaled, Minghui Zhang, and Barbara Ervens
Atmos. Chem. Phys., 22, 1989–2009, https://doi.org/10.5194/acp-22-1989-2022, https://doi.org/10.5194/acp-22-1989-2022, 2022
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Chemical reactions with iron in clouds and aerosol form and cycle reactive oxygen species (ROS). Previous model studies assumed that all cloud droplets (particles) contain iron, while single-particle analyses showed otherwise. By means of a model, we explore the bias in predicted ROS budgets by distributing a given iron mass to either all or only a few droplets (particles). Implications for oxidation potential, radical loss and iron oxidation state are discussed.
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Mike J. Newland, Yangang Ren, Max R. McGillen, Lisa Michelat, Véronique Daële, and Abdelwahid Mellouki
Atmos. Chem. Phys., 22, 1761–1772, https://doi.org/10.5194/acp-22-1761-2022, https://doi.org/10.5194/acp-22-1761-2022, 2022
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Wildfires are increasing in extent and severity, driven by climate change. Such fires emit large amounts of volatile organic compounds (VOCs) to the atmosphere. Many of these, such as the furans studied here, are very reactive and are rapidly converted to other VOCs, which are expected to have negative health effects and to further impact the climate. Here, we establish the importance of the nitrate radical for removing these compounds both during the night and during the day.
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Chaoyang Xue, Can Ye, Jörg Kleffmann, Wenjin Zhang, Xiaowei He, Pengfei Liu, Chenglong Zhang, Xiaoxi Zhao, Chengtang Liu, Zhuobiao Ma, Junfeng Liu, Jinhe Wang, Keding Lu, Valéry Catoire, Abdelwahid Mellouki, and Yujing Mu
Atmos. Chem. Phys., 22, 1035–1057, https://doi.org/10.5194/acp-22-1035-2022, https://doi.org/10.5194/acp-22-1035-2022, 2022
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Nitrous acid (HONO) and related parameters were measured at the foot and the summit of Mt. Tai in the summer of 2018. Based on measurements at the foot station, we utilized a box model to explore the roles of different sources in the HONO budget. We also studied radical chemistry in this high-ozone region.
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Ramon Campos Braga, Barbara Ervens, Daniel Rosenfeld, Meinrat O. Andreae, Jan-David Förster, Daniel Fütterer, Lianet Hernández Pardo, Bruna A. Holanda, Tina Jurkat-Witschas, Ovid O. Krüger, Oliver Lauer, Luiz A. T. Machado, Christopher Pöhlker, Daniel Sauer, Christiane Voigt, Adrian Walser, Manfred Wendisch, Ulrich Pöschl, and Mira L. Pöhlker
Atmos. Chem. Phys., 21, 17513–17528, https://doi.org/10.5194/acp-21-17513-2021, https://doi.org/10.5194/acp-21-17513-2021, 2021
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Interactions of aerosol particles with clouds represent a large uncertainty in estimates of climate change. Properties of aerosol particles control their ability to act as cloud condensation nuclei. Using aerosol measurements in the Amazon, we performed model studies to compare predicted and measured cloud droplet number concentrations at cloud bases. Our results confirm previous estimates of particle hygroscopicity in this region.
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Zhe Peng, Julia Lee-Taylor, Harald Stark, John J. Orlando, Bernard Aumont, and Jose L. Jimenez
Atmos. Chem. Phys., 21, 14649–14669, https://doi.org/10.5194/acp-21-14649-2021, https://doi.org/10.5194/acp-21-14649-2021, 2021
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We use the fully explicit GECKO-A model to study the OH reactivity (OHR) evolution in the NO-free photooxidation of several volatile organic compounds. Oxidation progressively produces more saturated and functionalized species, then breaks them into small species. OHR per C atom evolution is similar for different precursors once saturated multifunctional species are formed. We also find that partitioning of these species to chamber walls leads to large deviations in chambers from the atmosphere.
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Philipp G. Eger, Luc Vereecken, Rolf Sander, Jan Schuladen, Nicolas Sobanski, Horst Fischer, Einar Karu, Jonathan Williams, Ville Vakkari, Tuukka Petäjä, Jos Lelieveld, Andrea Pozzer, and John N. Crowley
Atmos. Chem. Phys., 21, 14333–14349, https://doi.org/10.5194/acp-21-14333-2021, https://doi.org/10.5194/acp-21-14333-2021, 2021
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We determine the impact of pyruvic acid photolysis on the formation of acetaldehyde and peroxy radicals during summer and autumn in the Finnish boreal forest using a data-constrained box model. Our results are dependent on the chosen scenario in which the overall quantum yield and the photolysis products are varied. We highlight that pyruvic acid photolysis can be an important contributor to acetaldehyde and peroxy radical formation in remote, forested regions.
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Ramon Campos Braga, Daniel Rosenfeld, Ovid O. Krüger, Barbara Ervens, Bruna A. Holanda, Manfred Wendisch, Trismono Krisna, Ulrich Pöschl, Meinrat O. Andreae, Christiane Voigt, and Mira L. Pöhlker
Atmos. Chem. Phys., 21, 14079–14088, https://doi.org/10.5194/acp-21-14079-2021, https://doi.org/10.5194/acp-21-14079-2021, 2021
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Quantifying the precipitation within clouds is crucial for our understanding of the Earth's hydrological cycle. Using in situ measurements of cloud and rain properties over the Amazon Basin and Atlantic Ocean, we show here a linear relationship between the effective radius (re) and precipitation water content near the tops of convective clouds for different pollution states and temperature levels. Our results emphasize the role of re to determine both initiation and amount of precipitation.
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Beth S. Nelson, Gareth J. Stewart, Will S. Drysdale, Mike J. Newland, Adam R. Vaughan, Rachel E. Dunmore, Pete M. Edwards, Alastair C. Lewis, Jacqueline F. Hamilton, W. Joe Acton, C. Nicholas Hewitt, Leigh R. Crilley, Mohammed S. Alam, Ülkü A. Şahin, David C. S. Beddows, William J. Bloss, Eloise Slater, Lisa K. Whalley, Dwayne E. Heard, James M. Cash, Ben Langford, Eiko Nemitz, Roberto Sommariva, Sam Cox, Shivani, Ranu Gadi, Bhola R. Gurjar, James R. Hopkins, Andrew R. Rickard, and James D. Lee
Atmos. Chem. Phys., 21, 13609–13630, https://doi.org/10.5194/acp-21-13609-2021, https://doi.org/10.5194/acp-21-13609-2021, 2021
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Ozone production at an urban site in Delhi is sensitive to volatile organic compound (VOC) concentrations, particularly those of the aromatic, monoterpene, and alkene VOC classes. The change in ozone production by varying atmospheric pollutants according to their sources, as defined in an emissions inventory, is investigated. The study suggests that reducing road transport emissions alone does not reduce reactive VOCs in the atmosphere enough to perturb an increase in ozone production.
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Yangang Ren, Li Zhou, Abdelwahid Mellouki, Véronique Daële, Mahmoud Idir, Steven S. Brown, Branko Ruscic, Robert S. Paton, Max R. McGillen, and A. R. Ravishankara
Atmos. Chem. Phys., 21, 13537–13551, https://doi.org/10.5194/acp-21-13537-2021, https://doi.org/10.5194/acp-21-13537-2021, 2021
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Aromatic aldehydes are a family of compounds emitted into the atmosphere from both anthropogenic and biogenic sources that are formed from the degradation of aromatic hydrocarbons. Their atmospheric degradation may impact air quality. We report on their atmospheric degradation through reaction with NO3, which is useful to estimate their atmospheric lifetimes. We have also attempted to elucidate the mechanism of these reactions via studies of isotopic substitution and quantum chemistry.
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R. Anthony Cox, Markus Ammann, John N. Crowley, Paul T. Griffiths, Hartmut Herrmann, Erik H. Hoffmann, Michael E. Jenkin, V. Faye McNeill, Abdelwahid Mellouki, Christopher J. Penkett, Andreas Tilgner, and Timothy J. Wallington
Atmos. Chem. Phys., 21, 13011–13018, https://doi.org/10.5194/acp-21-13011-2021, https://doi.org/10.5194/acp-21-13011-2021, 2021
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The term open-air factor was coined in the 1960s, establishing that rural air had powerful germicidal properties possibly resulting from immediate products of the reaction of ozone with alkenes, unsaturated compounds ubiquitously present in natural and polluted environments. We have re-evaluated those early experiments, applying the recently substantially improved knowledge, and put them into the context of the lifetime of aerosol-borne pathogens that are so important in the Covid-19 pandemic.
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Mira L. Pöhlker, Minghui Zhang, Ramon Campos Braga, Ovid O. Krüger, Ulrich Pöschl, and Barbara Ervens
Atmos. Chem. Phys., 21, 11723–11740, https://doi.org/10.5194/acp-21-11723-2021, https://doi.org/10.5194/acp-21-11723-2021, 2021
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Clouds cool our atmosphere. The role of small aerosol particles in affecting them represents one of the largest uncertainties in current estimates of climate change. Traditionally it is assumed that cloud droplets only form particles of diameters ~ 100 nm (
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accumulation mode). Previous studies suggest that this can also occur in smaller particles (
Aitken mode). Our study provides a general framework to estimate under which aerosol and cloud conditions Aitken mode particles affect clouds.
Isaac Kwadjo Afreh, Bernard Aumont, Marie Camredon, and Kelley Claire Barsanti
Atmos. Chem. Phys., 21, 11467–11487, https://doi.org/10.5194/acp-21-11467-2021, https://doi.org/10.5194/acp-21-11467-2021, 2021
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This is the first mechanistic modeling study of secondary organic aerosol (SOA) from the understudied monoterpene, camphene. The semi-explicit chemical model GECKO-A predicted camphene SOA yields that were ~2 times α-pinene. Using 50/50 α-pinene + limonene as a surrogate for camphene increased predicted SOA mass from biomass burning fuels by up to ~100 %. The accurate representation of camphene in air quality models can improve predictions of SOA when camphene is a dominant monoterpene.
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Yingnan Zhang, Likun Xue, William P. L. Carter, Chenglei Pei, Tianshu Chen, Jiangshan Mu, Yujun Wang, Qingzhu Zhang, and Wenxing Wang
Atmos. Chem. Phys., 21, 11053–11068, https://doi.org/10.5194/acp-21-11053-2021, https://doi.org/10.5194/acp-21-11053-2021, 2021
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We developed the localized incremental reactivity (IR) for VOCs in a Chinese megacity and elucidated their applications in calculating the ozone formation potential (OFP). The IR scales showed a strong dependence on chemical mechanisms. Both emission- and observation-based inputs are suitable for the MIR calculation but not the case under mixed-limited or NOx-limited O3 formation regimes. We provide suggestions for the application of IR and OFP scales to aid in VOC control in China.
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Caterina Mogno, Paul I. Palmer, Christoph Knote, Fei Yao, and Timothy J. Wallington
Atmos. Chem. Phys., 21, 10881–10909, https://doi.org/10.5194/acp-21-10881-2021, https://doi.org/10.5194/acp-21-10881-2021, 2021
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We use a 3-D atmospheric chemistry model to investigate how seasonal emissions sources and meteorological conditions affect the surface distribution of fine particulate matter (PM2.5) and organic aerosol (OA) over the Indo-Gangetic Plain. We find that all seasonal mean values of PM2.5 still exceed safe air quality levels, with human emissions contributing to PM2.5 all year round, open fires during post- and pre-monsoon, and biogenic emissions during monsoon. OA contributes up to 30 % to PM2.5.
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Esther Borrás, Luis A. Tortajada-Genaro, Milagro Ródenas, Teresa Vera, Thomas Speak, Paul Seakins, Marvin D. Shaw, Alastair C. Lewis, and Amalia Muñoz
Atmos. Meas. Tech., 14, 4989–4999, https://doi.org/10.5194/amt-14-4989-2021, https://doi.org/10.5194/amt-14-4989-2021, 2021
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This work presents promising results in the characterization of specific atmospheric pollutants (oxygenated VOCs) present at very low but highly relevant concentrations.
We carried out this research at EUPHORE facilities within the framework of the EUROCHAMP project. A new analytical method, with high robustness and precision, also clean in the use of solvents, low cost, and easily adaptable for use in mobile laboratories for air quality monitoring, is presented.
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Rongrong Wu, Luc Vereecken, Epameinondas Tsiligiannis, Sungah Kang, Sascha R. Albrecht, Luisa Hantschke, Defeng Zhao, Anna Novelli, Hendrik Fuchs, Ralf Tillmann, Thorsten Hohaus, Philip T. M. Carlsson, Justin Shenolikar, François Bernard, John N. Crowley, Juliane L. Fry, Bellamy Brownwood, Joel A. Thornton, Steven S. Brown, Astrid Kiendler-Scharr, Andreas Wahner, Mattias Hallquist, and Thomas F. Mentel
Atmos. Chem. Phys., 21, 10799–10824, https://doi.org/10.5194/acp-21-10799-2021, https://doi.org/10.5194/acp-21-10799-2021, 2021
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Isoprene is the biogenic volatile organic compound with the largest emissions rates. The nighttime reaction of isoprene with the NO3 radical has a large potential to contribute to SOA. We classified isoprene nitrates into generations and proposed formation pathways. Considering the potential functionalization of the isoprene nitrates we propose that mainly isoprene dimers contribute to SOA formation from the isoprene NO3 reactions with at least a 5 % mass yield.
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Tommaso Galeazzo, Richard Valorso, Ying Li, Marie Camredon, Bernard Aumont, and Manabu Shiraiwa
Atmos. Chem. Phys., 21, 10199–10213, https://doi.org/10.5194/acp-21-10199-2021, https://doi.org/10.5194/acp-21-10199-2021, 2021
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We simulate SOA viscosity with explicit modeling of gas-phase oxidation of isoprene and α-pinene. While the viscosity dependence on relative humidity and mass loadings is captured well by simulations, the model underestimates measured viscosity, indicating missing processes. Kinetic limitations and reduction in mass accommodation may cause an increase in viscosity. The developed model is powerful for investigation of the interplay among gas reactions, chemical composition and phase state.
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Defeng Zhao, Iida Pullinen, Hendrik Fuchs, Stephanie Schrade, Rongrong Wu, Ismail-Hakki Acir, Ralf Tillmann, Franz Rohrer, Jürgen Wildt, Yindong Guo, Astrid Kiendler-Scharr, Andreas Wahner, Sungah Kang, Luc Vereecken, and Thomas F. Mentel
Atmos. Chem. Phys., 21, 9681–9704, https://doi.org/10.5194/acp-21-9681-2021, https://doi.org/10.5194/acp-21-9681-2021, 2021
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The reaction of isoprene, a biogenic volatile organic compound with the globally largest emission rates, with NO3, an nighttime oxidant influenced heavily by anthropogenic emissions, forms a large number of highly oxygenated organic molecules (HOM). These HOM are formed via one or multiple oxidation steps, followed by autoxidation. Their total yield is much higher than that in the daytime oxidation of isoprene. They may play an important role in nighttime organic aerosol formation and growth.
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Gabriel Isaacman-VanWertz and Bernard Aumont
Atmos. Chem. Phys., 21, 6541–6563, https://doi.org/10.5194/acp-21-6541-2021, https://doi.org/10.5194/acp-21-6541-2021, 2021
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There are tens of thousands of different chemical compounds in the atmosphere. To tackle this complexity, there are a wide range of different methods to estimate their physical and chemical properties. We use these methods to understand how much the detailed structure of a molecule impacts its properties, and the extent to which properties can be estimated without knowing this level of detail. We find that structure matters, but methods lacking that level of detail still perform reasonably well.
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Abdelwahid Mellouki, Markus Ammann, R. Anthony Cox, John N. Crowley, Hartmut Herrmann, Michael E. Jenkin, V. Faye McNeill, Jürgen Troe, and Timothy J. Wallington
Atmos. Chem. Phys., 21, 4797–4808, https://doi.org/10.5194/acp-21-4797-2021, https://doi.org/10.5194/acp-21-4797-2021, 2021
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Volatile organic compounds play an important role in atmospheric chemistry. This article, the eighth in the series, presents kinetic and photochemical data sheets evaluated by the IUPAC Task Group on Atmospheric Chemical Kinetic Data Evaluation. It covers the gas-phase reactions of organic species with four, or more, carbon atoms (≥ C4) including thermal reactions of closed-shell organic species with HO and NO3 radicals and their photolysis. These data are important for atmospheric models.
This article is included in the Encyclopedia of Geosciences
Minghui Zhang, Amina Khaled, Pierre Amato, Anne-Marie Delort, and Barbara Ervens
Atmos. Chem. Phys., 21, 3699–3724, https://doi.org/10.5194/acp-21-3699-2021, https://doi.org/10.5194/acp-21-3699-2021, 2021
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Although primary biological aerosol particles (PBAPs, bioaerosols) represent a small fraction of total atmospheric aerosol burden, they might affect climate and public health. We summarize which PBAP properties are important to affect their inclusion in clouds and interaction with light and might also affect their residence time and transport in the atmosphere. Our study highlights that not only chemical and physical but also biological processes can modify these physicochemical properties.
This article is included in the Encyclopedia of Geosciences
Amina Khaled, Minghui Zhang, Pierre Amato, Anne-Marie Delort, and Barbara Ervens
Atmos. Chem. Phys., 21, 3123–3141, https://doi.org/10.5194/acp-21-3123-2021, https://doi.org/10.5194/acp-21-3123-2021, 2021
Gareth J. Stewart, Beth S. Nelson, W. Joe F. Acton, Adam R. Vaughan, Naomi J. Farren, James R. Hopkins, Martyn W. Ward, Stefan J. Swift, Rahul Arya, Arnab Mondal, Ritu Jangirh, Sakshi Ahlawat, Lokesh Yadav, Sudhir K. Sharma, Siti S. M. Yunus, C. Nicholas Hewitt, Eiko Nemitz, Neil Mullinger, Ranu Gadi, Lokesh K. Sahu, Nidhi Tripathi, Andrew R. Rickard, James D. Lee, Tuhin K. Mandal, and Jacqueline F. Hamilton
Atmos. Chem. Phys., 21, 2407–2426, https://doi.org/10.5194/acp-21-2407-2021, https://doi.org/10.5194/acp-21-2407-2021, 2021
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Biomass burning releases many lower-molecular-weight organic species which are difficult to analyse but important for the formation of organic aerosol. This study examined a new high-resolution technique to better characterise these difficult-to-analyse organic components. Some burning sources analysed in this study, such as cow dung cake and municipal solid waste, released extremely complex mixtures containing many thousands of different lower-volatility organic compounds.
This article is included in the Encyclopedia of Geosciences
Gareth J. Stewart, W. Joe F. Acton, Beth S. Nelson, Adam R. Vaughan, James R. Hopkins, Rahul Arya, Arnab Mondal, Ritu Jangirh, Sakshi Ahlawat, Lokesh Yadav, Sudhir K. Sharma, Rachel E. Dunmore, Siti S. M. Yunus, C. Nicholas Hewitt, Eiko Nemitz, Neil Mullinger, Ranu Gadi, Lokesh K. Sahu, Nidhi Tripathi, Andrew R. Rickard, James D. Lee, Tuhin K. Mandal, and Jacqueline F. Hamilton
Atmos. Chem. Phys., 21, 2383–2406, https://doi.org/10.5194/acp-21-2383-2021, https://doi.org/10.5194/acp-21-2383-2021, 2021
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Biomass burning is a major source of trace gases to the troposphere; however, the composition and quantity of emissions vary greatly between different fuel types. This work provided near-total quantitation of non-methane volatile organic compounds from combustion of biofuels from India. Emissions from cow dung cake combustion were significantly larger than conventional fuelwood combustion, potentially indicating that this source has a disproportionately large impact on regional air quality.
This article is included in the Encyclopedia of Geosciences
Saly Jaber, Muriel Joly, Maxence Brissy, Martin Leremboure, Amina Khaled, Barbara Ervens, and Anne-Marie Delort
Biogeosciences, 18, 1067–1080, https://doi.org/10.5194/bg-18-1067-2021, https://doi.org/10.5194/bg-18-1067-2021, 2021
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Our study is of interest to atmospheric scientists and environmental microbiologists, as we show that clouds can be considered a medium where bacteria efficiently degrade and transform amino acids, in competition with chemical processes. As current atmospheric multiphase models are restricted to chemical degradation of organic compounds, our conclusions motivate further model development.
This article is included in the Encyclopedia of Geosciences
Mike J. Newland, Daniel J. Bryant, Rachel E. Dunmore, Thomas J. Bannan, W. Joe F. Acton, Ben Langford, James R. Hopkins, Freya A. Squires, William Dixon, William S. Drysdale, Peter D. Ivatt, Mathew J. Evans, Peter M. Edwards, Lisa K. Whalley, Dwayne E. Heard, Eloise J. Slater, Robert Woodward-Massey, Chunxiang Ye, Archit Mehra, Stephen D. Worrall, Asan Bacak, Hugh Coe, Carl J. Percival, C. Nicholas Hewitt, James D. Lee, Tianqu Cui, Jason D. Surratt, Xinming Wang, Alastair C. Lewis, Andrew R. Rickard, and Jacqueline F. Hamilton
Atmos. Chem. Phys., 21, 1613–1625, https://doi.org/10.5194/acp-21-1613-2021, https://doi.org/10.5194/acp-21-1613-2021, 2021
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We report the formation of secondary pollutants in the urban megacity of Beijing that are typically associated with remote regions such as rainforests. This is caused by extremely low levels of nitric oxide (NO), typically expected to be high in urban areas, observed in the afternoon. This work has significant implications for how we understand atmospheric chemistry in the urban environment and thus for how to implement effective policies to improve urban air quality.
This article is included in the Encyclopedia of Geosciences
Matias Berasategui, Damien Amedro, Luc Vereecken, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 20, 13541–13555, https://doi.org/10.5194/acp-20-13541-2020, https://doi.org/10.5194/acp-20-13541-2020, 2020
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Peracetic acid is one of the most abundant organic peroxides in the atmosphere. We combine experiments and theory to show that peracetic acid reacts orders of magnitude more slowly with OH than presently accepted, which results in a significant extension of its atmospheric lifetime.
This article is included in the Encyclopedia of Geosciences
R. Anthony Cox, Markus Ammann, John N. Crowley, Hartmut Herrmann, Michael E. Jenkin, V. Faye McNeill, Abdelwahid Mellouki, Jürgen Troe, and Timothy J. Wallington
Atmos. Chem. Phys., 20, 13497–13519, https://doi.org/10.5194/acp-20-13497-2020, https://doi.org/10.5194/acp-20-13497-2020, 2020
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Criegee intermediates, formed from alkene–ozone reactions, play a potentially important role as tropospheric oxidants. Evaluated kinetic data are provided for reactions governing their formation and removal for use in atmospheric models. These include their formation from reactions of simple and complex alkenes and removal by decomposition and reaction with a number of atmospheric species (e.g. H2O, SO2). An overview of the tropospheric chemistry of Criegee intermediates is also provided.
This article is included in the Encyclopedia of Geosciences
Yangang Ren, Bastian Stieger, Gerald Spindler, Benoit Grosselin, Abdelwahid Mellouki, Thomas Tuch, Alfred Wiedensohler, and Hartmut Herrmann
Atmos. Chem. Phys., 20, 13069–13089, https://doi.org/10.5194/acp-20-13069-2020, https://doi.org/10.5194/acp-20-13069-2020, 2020
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We present HONO measurements from the TROPOS research site in Melpitz, Germany. Investigations of HONO sources and sinks revealed the nighttime formation by heterogeneous conversion of NO2 to HONO followed by a significant surface deposition at night. The evaporation of dew was identified as the main HONO source in the morning. In the following, dew measurements with a self-made dew collector were performed to estimate the amount of evaporated HONO from dew in the atmospheric HONO distribution.
This article is included in the Encyclopedia of Geosciences
Mei-Tsan Kuo, Isabelle Weber, Christa Fittschen, Luc Vereecken, and Jim Jr-Min Lin
Atmos. Chem. Phys., 20, 12983–12993, https://doi.org/10.5194/acp-20-12983-2020, https://doi.org/10.5194/acp-20-12983-2020, 2020
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Dimethyl sulfide (DMS) is the major sulfur-containing species in the troposphere. Previous work by Newland et al. (2015) reported very high reactivity of isoprene-derived Criegee intermediates (CIs) towards DMS. By monitoring CIs with direct UV absorption, we found CI + DMS reactions are very slow, in contrast to the results of Newland et al. (2015), suggesting these CIs would not oxidize atmospheric DMS at any substantial level.
This article is included in the Encyclopedia of Geosciences
Michael E. Jenkin, Richard Valorso, Bernard Aumont, Mike J. Newland, and Andrew R. Rickard
Atmos. Chem. Phys., 20, 12921–12937, https://doi.org/10.5194/acp-20-12921-2020, https://doi.org/10.5194/acp-20-12921-2020, 2020
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Unsaturated organic compounds are emitted in large quantities from natural and human-influenced sources. Atmospheric removal occurs significantly by reaction with ozone, initiating reaction sequences forming free radicals and organic pollutants in the gaseous and particulate phases. Due to their very large number, it is impossible to study the reaction rate for every compound, and most have to be estimated. Updated and extended estimation methods are reported for use in atmospheric models.
This article is included in the Encyclopedia of Geosciences
Jianghanyang Li, Xuan Zhang, John Orlando, Geoffrey Tyndall, and Greg Michalski
Atmos. Chem. Phys., 20, 9805–9819, https://doi.org/10.5194/acp-20-9805-2020, https://doi.org/10.5194/acp-20-9805-2020, 2020
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Nitrogen isotopic compositions of atmospheric reactive nitrogen are widely used to infer their sources. However, the reactions between NO and NO2 strongly impact their isotopes, which was not well understood. We conducted a series of experiments in an atmospheric simulation chamber to determine the isotopic effects of (1) direct isotopic exchange between NO and NO2 and (2) the isotopic fractionations during NOx photochemistry, then developed an equation to quantify the overall isotopic effect.
This article is included in the Encyclopedia of Geosciences
Archit Mehra, Yuwei Wang, Jordan E. Krechmer, Andrew Lambe, Francesca Majluf, Melissa A. Morris, Michael Priestley, Thomas J. Bannan, Daniel J. Bryant, Kelly L. Pereira, Jacqueline F. Hamilton, Andrew R. Rickard, Mike J. Newland, Harald Stark, Philip Croteau, John T. Jayne, Douglas R. Worsnop, Manjula R. Canagaratna, Lin Wang, and Hugh Coe
Atmos. Chem. Phys., 20, 9783–9803, https://doi.org/10.5194/acp-20-9783-2020, https://doi.org/10.5194/acp-20-9783-2020, 2020
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Aromatic volatile organic compounds (VOCs) emitted from anthropogenic activity are important for tropospheric ozone and secondary organic aerosol (SOA) formation. Here we present a detailed chemical characterisation of SOA from four C9-aromatic isomers and a polycyclic aromatic hydrocarbon (PAH). We identify and compare their oxidation products in the gas and particle phases, showing the different relative importance of oxidation pathways and proportions of highly oxygenated organic molecules.
This article is included in the Encyclopedia of Geosciences
Jacob T. Shaw, Andrew R. Rickard, Mike J. Newland, and Terry J. Dillon
Atmos. Chem. Phys., 20, 9725–9736, https://doi.org/10.5194/acp-20-9725-2020, https://doi.org/10.5194/acp-20-9725-2020, 2020
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This work expands upon the recently developed multivariate relative rate technique, presented in Shaw et al. (2019), for the measurement of rates of reaction between aromatic and aliphatic volatile organic compounds (VOCs) and OH. Knowledge of the rates of such reactions are important for understanding air quality in urban environments. This work also provides a key validation of structure–activity relationship models, which provide a theoretical method for estimating OH + VOC kinetics.
This article is included in the Encyclopedia of Geosciences
Daniel J. Bryant, William J. Dixon, James R. Hopkins, Rachel E. Dunmore, Kelly L. Pereira, Marvin Shaw, Freya A. Squires, Thomas J. Bannan, Archit Mehra, Stephen D. Worrall, Asan Bacak, Hugh Coe, Carl J. Percival, Lisa K. Whalley, Dwayne E. Heard, Eloise J. Slater, Bin Ouyang, Tianqu Cui, Jason D. Surratt, Di Liu, Zongbo Shi, Roy Harrison, Yele Sun, Weiqi Xu, Alastair C. Lewis, James D. Lee, Andrew R. Rickard, and Jacqueline F. Hamilton
Atmos. Chem. Phys., 20, 7531–7552, https://doi.org/10.5194/acp-20-7531-2020, https://doi.org/10.5194/acp-20-7531-2020, 2020
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Using the chemical composition of offline filter samples, we report that a large share of oxidized organic aerosol in Beijing during summer is due to isoprene secondary organic aerosol (iSOA). iSOA organosulfates showed a strong correlation with the product of ozone and particulate sulfate. This highlights the role of both photochemistry and the availability of particulate sulfate in heterogeneous reactions and further demonstrates that iSOA formation is controlled by anthropogenic emissions.
This article is included in the Encyclopedia of Geosciences
Luc Vereecken and Barbara Nozière
Atmos. Chem. Phys., 20, 7429–7458, https://doi.org/10.5194/acp-20-7429-2020, https://doi.org/10.5194/acp-20-7429-2020, 2020
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Alkyl peroxy radicals, RO2, are important intermediates in the oxidation of organic material in the atmosphere. It was shown earlier that hydrogen atom migration within RO2 can be important and results in the formation of additional oxidants and large highly oxygenated molecules that lead to more and larger aerosols. In this work we propose a method for predicting the chemical rate for these H migrations in RO2, helping atmospheric models to correctly include these reactions.
This article is included in the Encyclopedia of Geosciences
Robert Woodward-Massey, Eloise J. Slater, Jake Alen, Trevor Ingham, Danny R. Cryer, Leanne M. Stimpson, Chunxiang Ye, Paul W. Seakins, Lisa K. Whalley, and Dwayne E. Heard
Atmos. Meas. Tech., 13, 3119–3146, https://doi.org/10.5194/amt-13-3119-2020, https://doi.org/10.5194/amt-13-3119-2020, 2020
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The OH radical is known as nature’s detergent, removing most trace gases from the atmosphere. Hence, an accurate measurement of its concentration is very important. We present measurements of OH in several field locations using a laser-based fluorescence method equipped with an OH scavenger. By determining the background signal in two different ways, we show that the instrument does not suffer any significant interferences that could result in an overestimation of OH concentrations.
This article is included in the Encyclopedia of Geosciences
Simon Rosanka, Giang H. T. Vu, Hue M. T. Nguyen, Tien V. Pham, Umar Javed, Domenico Taraborrelli, and Luc Vereecken
Atmos. Chem. Phys., 20, 6671–6686, https://doi.org/10.5194/acp-20-6671-2020, https://doi.org/10.5194/acp-20-6671-2020, 2020
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Isocyanic acid, HNCO, is a toxic chemical compound emitted to the atmosphere by biomass burning and by unwanted release in NOx mitigation systems in vehicles such as the AdBlue system. We have studied the loss processes of HNCO, finding that it is unreactive to most atmospheric oxidants and thus has a long chemical lifetime. The main removal is then by deposition on surfaces and transition to aqueous phase, such as clouds. The long lifetime also allows it to be transported to the stratosphere.
This article is included in the Encyclopedia of Geosciences
Max R. McGillen, William P. L. Carter, Abdelwahid Mellouki, John J. Orlando, Bénédicte Picquet-Varrault, and Timothy J. Wallington
Earth Syst. Sci. Data, 12, 1203–1216, https://doi.org/10.5194/essd-12-1203-2020, https://doi.org/10.5194/essd-12-1203-2020, 2020
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The gas-phase reactions of organic compounds in the atmosphere are a crucial step in the degradation of anthropogenic and biogenic emissions and the formation of secondary pollutants. This work is an attempt to produce a dataset that is as comprehensive as possible regarding the multitude of chemicals that react in the atmosphere. We find that we are able to make substantial improvements upon previous compendia and that this progress will help improve our understanding of atmospheric chemistry.
This article is included in the Encyclopedia of Geosciences
Camille Mouchel-Vallon, Julia Lee-Taylor, Alma Hodzic, Paulo Artaxo, Bernard Aumont, Marie Camredon, David Gurarie, Jose-Luis Jimenez, Donald H. Lenschow, Scot T. Martin, Janaina Nascimento, John J. Orlando, Brett B. Palm, John E. Shilling, Manish Shrivastava, and Sasha Madronich
Atmos. Chem. Phys., 20, 5995–6014, https://doi.org/10.5194/acp-20-5995-2020, https://doi.org/10.5194/acp-20-5995-2020, 2020
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The GoAmazon 2014/5 field campaign took place near the city of Manaus, Brazil, isolated in the Amazon rainforest, to study the impacts of urban pollution on natural air masses. We simulated this campaign with an extremely detailed organic chemistry model to understand how the city would affect the growth and composition of natural aerosol particles. Discrepancies between the model and the measurements indicate that the chemistry of naturally emitted organic compounds is still poorly understood.
This article is included in the Encyclopedia of Geosciences
Lavinia Onel, Alexander Brennan, Michele Gianella, James Hooper, Nicole Ng, Gus Hancock, Lisa Whalley, Paul W. Seakins, Grant A. D. Ritchie, and Dwayne E. Heard
Atmos. Meas. Tech., 13, 2441–2456, https://doi.org/10.5194/amt-13-2441-2020, https://doi.org/10.5194/amt-13-2441-2020, 2020
Saly Jaber, Audrey Lallement, Martine Sancelme, Martin Leremboure, Gilles Mailhot, Barbara Ervens, and Anne-Marie Delort
Atmos. Chem. Phys., 20, 4987–4997, https://doi.org/10.5194/acp-20-4987-2020, https://doi.org/10.5194/acp-20-4987-2020, 2020
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Current atmospheric multiphase models do not include biotransformations of organic compounds by bacteria, although many previous studies of our and other research groups have shown microbial activity in cloud water. The current lab/model study shows that for water-soluble aromatic compounds, biodegradation by bacteria may be as efficient as chemical reactions in cloud water.
This article is included in the Encyclopedia of Geosciences
Victor Lannuque, Florian Couvidat, Marie Camredon, Bernard Aumont, and Bertrand Bessagnet
Atmos. Chem. Phys., 20, 4905–4931, https://doi.org/10.5194/acp-20-4905-2020, https://doi.org/10.5194/acp-20-4905-2020, 2020
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Large uncertainties remain in modeling secondary organic aerosol (SOA) and evolution and properties in air quality models. In this article, the recently developed VBS-GECKO parameterization for SOA formation has been implemented in the air quality model CHIMERE. Simulations have been driven to identify the main SOA sources and to evaluate the sensitivity of simulated SOA concentrations to (i) secondary organic compound properties and (ii) emissions from traffic and transportation sources.
This article is included in the Encyclopedia of Geosciences
Rebecca H. Schwantes, Louisa K. Emmons, John J. Orlando, Mary C. Barth, Geoffrey S. Tyndall, Samuel R. Hall, Kirk Ullmann, Jason M. St. Clair, Donald R. Blake, Armin Wisthaler, and Thao Paul V. Bui
Atmos. Chem. Phys., 20, 3739–3776, https://doi.org/10.5194/acp-20-3739-2020, https://doi.org/10.5194/acp-20-3739-2020, 2020
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Ozone is a greenhouse gas and air pollutant that is harmful to human health and plants. During the summer in the southeastern US, many regional and global models are biased high for surface ozone compared to observations. Here adding more complex and updated chemistry for isoprene and terpenes, which are biogenic hydrocarbons emitted from trees and vegetation, into an earth system model greatly reduces the simulated surface ozone bias compared to aircraft and monitoring station data.
This article is included in the Encyclopedia of Geosciences
Anna Novelli, Luc Vereecken, Birger Bohn, Hans-Peter Dorn, Georgios I. Gkatzelis, Andreas Hofzumahaus, Frank Holland, David Reimer, Franz Rohrer, Simon Rosanka, Domenico Taraborrelli, Ralf Tillmann, Robert Wegener, Zhujun Yu, Astrid Kiendler-Scharr, Andreas Wahner, and Hendrik Fuchs
Atmos. Chem. Phys., 20, 3333–3355, https://doi.org/10.5194/acp-20-3333-2020, https://doi.org/10.5194/acp-20-3333-2020, 2020
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Experimental evidence from a simulation chamber study shows that the regeneration efficiency of the hydroxyl radical is maintained globally at values higher than 0.5 for a wide range of nitrogen oxide concentrations as a result of isomerizations of peroxy radicals originating from the OH oxidation of isoprene. The available models were tested, and suggestions on how to improve their ability to reproduce the measured radical and oxygenated volatile organic compound concentrations are provided.
This article is included in the Encyclopedia of Geosciences
Thomas H. Speak, Mark A. Blitz, Daniel Stone, and Paul W. Seakins
Atmos. Meas. Tech., 13, 839–852, https://doi.org/10.5194/amt-13-839-2020, https://doi.org/10.5194/amt-13-839-2020, 2020
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OH and HO2 radicals are important trace constituents of the atmosphere that are closely coupled via several types of reaction. This paper describes a new laboratory method to simultaneously determine OH kinetics and HO2 yields from chemical processes. The instrument also provides some time resolution on HO2 detection allowing one to separate HO2 produced from the target reaction from HO2 arising from secondary chemistry. Examples of applications are presented.
This article is included in the Encyclopedia of Geosciences
Barbara Ervens and Pierre Amato
Atmos. Chem. Phys., 20, 1777–1794, https://doi.org/10.5194/acp-20-1777-2020, https://doi.org/10.5194/acp-20-1777-2020, 2020
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Bacteria in the atmosphere are important due to their potential adverse health effects and as initiators of ice cloud formation. Observational studies suggest that bacterial cells grow and multiply in clouds and also consume organic compounds.
We estimate the role of microbial processes in the atmosphere for (i) the increase in biological aerosol mass by cell growth and multiplication and (ii) the sink strength of organics in clouds as a loss process in addition to chemical reactions.
This article is included in the Encyclopedia of Geosciences
Roberto Sommariva, Sam Cox, Chris Martin, Kasia Borońska, Jenny Young, Peter K. Jimack, Michael J. Pilling, Vasileios N. Matthaios, Beth S. Nelson, Mike J. Newland, Marios Panagi, William J. Bloss, Paul S. Monks, and Andrew R. Rickard
Geosci. Model Dev., 13, 169–183, https://doi.org/10.5194/gmd-13-169-2020, https://doi.org/10.5194/gmd-13-169-2020, 2020
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This paper presents the AtChem software, which can be used to build box models for atmospheric chemistry studies. The software is designed to facilitate the use of one of the most important chemical mechanisms used by atmospheric scientists, the Master Chemical Mechanism. AtChem exists in two versions: an on-line application for laboratory studies and educational or outreach activities and an offline version for more complex models and batch simulations. AtChem is open source under MIT License.
This article is included in the Encyclopedia of Geosciences
Xuan Zhang, Haofei Zhang, Wen Xu, Xiaokang Wu, Geoffrey S. Tyndall, John J. Orlando, John T. Jayne, Douglas R. Worsnop, and Manjula R. Canagaratna
Atmos. Meas. Tech., 12, 5535–5545, https://doi.org/10.5194/amt-12-5535-2019, https://doi.org/10.5194/amt-12-5535-2019, 2019
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We develop a new technique to characterize organic nitrates as intact molecules in atmospheric aerosols, and we apply this technique to identify hydroxy nitrates in secondary organic aerosols produced from the photochemical oxidation of isoprene.
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Peter Bräuer, Camille Mouchel-Vallon, Andreas Tilgner, Anke Mutzel, Olaf Böge, Maria Rodigast, Laurent Poulain, Dominik van Pinxteren, Ralf Wolke, Bernard Aumont, and Hartmut Herrmann
Atmos. Chem. Phys., 19, 9209–9239, https://doi.org/10.5194/acp-19-9209-2019, https://doi.org/10.5194/acp-19-9209-2019, 2019
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The article presents a new protocol for computer-assisted automated aqueous-phase chemistry mechanism generation, which has been validated against chamber experiments. Together with a large kinetics database and improved prediction methods for kinetic data, the novel protocol provides an unmatched tool for detailed studies of tropospheric aqueous-phase chemistry in complex model studies and for the design and analysis of chamber experiments.
This article is included in the Encyclopedia of Geosciences
Michael E. Jenkin, Richard Valorso, Bernard Aumont, and Andrew R. Rickard
Atmos. Chem. Phys., 19, 7691–7717, https://doi.org/10.5194/acp-19-7691-2019, https://doi.org/10.5194/acp-19-7691-2019, 2019
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Organic compounds are emitted in large amounts from natural and human-influenced sources. Peroxy radicals are key intermediates formed during oxidation of organic compounds, and play a central role in mechanisms forming pollutants such as ozone and organic particles. Due to the large number of different peroxy radicals formed, it is impossible to study the rates of all of their reactions, and most have to be estimated. Updated and new estimation methods are reported for use in atmospheric models
This article is included in the Encyclopedia of Geosciences
Zongbo Shi, Tuan Vu, Simone Kotthaus, Roy M. Harrison, Sue Grimmond, Siyao Yue, Tong Zhu, James Lee, Yiqun Han, Matthias Demuzere, Rachel E. Dunmore, Lujie Ren, Di Liu, Yuanlin Wang, Oliver Wild, James Allan, W. Joe Acton, Janet Barlow, Benjamin Barratt, David Beddows, William J. Bloss, Giulia Calzolai, David Carruthers, David C. Carslaw, Queenie Chan, Lia Chatzidiakou, Yang Chen, Leigh Crilley, Hugh Coe, Tie Dai, Ruth Doherty, Fengkui Duan, Pingqing Fu, Baozhu Ge, Maofa Ge, Daobo Guan, Jacqueline F. Hamilton, Kebin He, Mathew Heal, Dwayne Heard, C. Nicholas Hewitt, Michael Hollaway, Min Hu, Dongsheng Ji, Xujiang Jiang, Rod Jones, Markus Kalberer, Frank J. Kelly, Louisa Kramer, Ben Langford, Chun Lin, Alastair C. Lewis, Jie Li, Weijun Li, Huan Liu, Junfeng Liu, Miranda Loh, Keding Lu, Franco Lucarelli, Graham Mann, Gordon McFiggans, Mark R. Miller, Graham Mills, Paul Monk, Eiko Nemitz, Fionna O'Connor, Bin Ouyang, Paul I. Palmer, Carl Percival, Olalekan Popoola, Claire Reeves, Andrew R. Rickard, Longyi Shao, Guangyu Shi, Dominick Spracklen, David Stevenson, Yele Sun, Zhiwei Sun, Shu Tao, Shengrui Tong, Qingqing Wang, Wenhua Wang, Xinming Wang, Xuejun Wang, Zifang Wang, Lianfang Wei, Lisa Whalley, Xuefang Wu, Zhijun Wu, Pinhua Xie, Fumo Yang, Qiang Zhang, Yanli Zhang, Yuanhang Zhang, and Mei Zheng
Atmos. Chem. Phys., 19, 7519–7546, https://doi.org/10.5194/acp-19-7519-2019, https://doi.org/10.5194/acp-19-7519-2019, 2019
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APHH-Beijing is a collaborative international research programme to study the sources, processes and health effects of air pollution in Beijing. This introduction to the special issue provides an overview of (i) the APHH-Beijing programme, (ii) the measurement and modelling activities performed as part of it and (iii) the air quality and meteorological conditions during joint intensive field campaigns as a core activity within APHH-Beijing.
This article is included in the Encyclopedia of Geosciences
Zhe Peng, Julia Lee-Taylor, John J. Orlando, Geoffrey S. Tyndall, and Jose L. Jimenez
Atmos. Chem. Phys., 19, 813–834, https://doi.org/10.5194/acp-19-813-2019, https://doi.org/10.5194/acp-19-813-2019, 2019
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The use of oxidation flow reactors (OFRs) has been rapidly increasing. We investigate organic peroxy radical (RO2) chemistry in OFRs by kinetic modeling. It is found that, at low NO, UV intensity should be limited to avoid high radical levels leading to significant reaction of RO2 with OH and negligible RO2 isomerization, both of which are atmospherically irrelevant. We also develop two RO2 fate estimators (for general use and for OFRs) to aid experiment design and interpretation.
This article is included in the Encyclopedia of Geosciences
Barbara Ervens, Armin Sorooshian, Abdulmonam M. Aldhaif, Taylor Shingler, Ewan Crosbie, Luke Ziemba, Pedro Campuzano-Jost, Jose L. Jimenez, and Armin Wisthaler
Atmos. Chem. Phys., 18, 16099–16119, https://doi.org/10.5194/acp-18-16099-2018, https://doi.org/10.5194/acp-18-16099-2018, 2018
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The paper presents a new framework that can be used to identify emission scenarios in which aerosol populations are most likely modified by chemical processes in clouds. We show that in neither very polluted nor in very clean air masses is this the case. Only if the ratio of possible aerosol mass precursors (sulfur dioxide, some organics) and preexisting aerosol mass is sufficiently high will aerosol particles show substantially modified physicochemical properties upon cloud processing.
This article is included in the Encyclopedia of Geosciences
Zhong Li, Chunlin Li, Xingnan Ye, Hongbo Fu, Lin Wang, Xin Yang, Xinke Wang, Zhuohui Zhao, Haidong Kan, Abdelwahid Mellouki, and Jianmin Chen
Atmos. Chem. Phys., 18, 14445–14464, https://doi.org/10.5194/acp-18-14445-2018, https://doi.org/10.5194/acp-18-14445-2018, 2018
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Air quality over the Yangtze River is important as it may significantly influence aquatic ecosystems, public health, and coastal areas. A comprehensive 15-day cruise campaign, TEMP, was performed in the mid–lower reaches of the Yangtze River in winter of 2015. Based on the filter samples, the chemical composition of PM2.5 greatly varied or fluctuated.
This article is included in the Encyclopedia of Geosciences
Victor Lannuque, Marie Camredon, Florian Couvidat, Alma Hodzic, Richard Valorso, Sasha Madronich, Bertrand Bessagnet, and Bernard Aumont
Atmos. Chem. Phys., 18, 13411–13428, https://doi.org/10.5194/acp-18-13411-2018, https://doi.org/10.5194/acp-18-13411-2018, 2018
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Large uncertainties remain in understanding the influence of atmospheric environmental conditions on secondary organic aerosol (SOA) formation, evolution and properties. In this article, the GECKO-A modelling tool has been used in a box model under various environmental conditions to (i) explore the sensitivity of SOA formation and properties to changes on physical and chemical conditions and (ii) develop a volatility-basis-set-type parameterization for air quality models.
This article is included in the Encyclopedia of Geosciences
Michael E. Jenkin, Richard Valorso, Bernard Aumont, Andrew R. Rickard, and Timothy J. Wallington
Atmos. Chem. Phys., 18, 9297–9328, https://doi.org/10.5194/acp-18-9297-2018, https://doi.org/10.5194/acp-18-9297-2018, 2018
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Organic compounds are emitted in large quantities from natural and human-influenced sources. Removal from the atmosphere occurs mainly by reaction with hydroxyl (OH) radicals, and initiates reaction sequences forming pollutants such as ozone and organic particles. Due to their very large number, it is impossible to measure the removal rate for all compounds, and most have to be estimated. An updated and extended estimation method is reported for use in atmospheric models and impact assessments.
This article is included in the Encyclopedia of Geosciences
Michael E. Jenkin, Richard Valorso, Bernard Aumont, Andrew R. Rickard, and Timothy J. Wallington
Atmos. Chem. Phys., 18, 9329–9349, https://doi.org/10.5194/acp-18-9329-2018, https://doi.org/10.5194/acp-18-9329-2018, 2018
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Organic compounds are emitted in large quantities from natural and human-influenced sources. Removal from the atmosphere occurs mainly by reaction with hydroxyl (OH) radicals, and initiates reaction sequences forming pollutants such as ozone and organic particles. Due to their very large number, it is impossible to measure the removal rate for all compounds, and most have to be estimated. An updated and extended estimation method is reported for use in atmospheric models and impact assessments.
This article is included in the Encyclopedia of Geosciences
Hendrik Fuchs, Sascha Albrecht, Ismail–Hakki Acir, Birger Bohn, Martin Breitenlechner, Hans-Peter Dorn, Georgios I. Gkatzelis, Andreas Hofzumahaus, Frank Holland, Martin Kaminski, Frank N. Keutsch, Anna Novelli, David Reimer, Franz Rohrer, Ralf Tillmann, Luc Vereecken, Robert Wegener, Alexander Zaytsev, Astrid Kiendler-Scharr, and Andreas Wahner
Atmos. Chem. Phys., 18, 8001–8016, https://doi.org/10.5194/acp-18-8001-2018, https://doi.org/10.5194/acp-18-8001-2018, 2018
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The photooxidation of methyl vinyl ketone MVK, one of the most important products of isoprene that is emitted by plants, was investigated in the atmospheric simulation chamber SAPHIR for conditions found in forested areas. The comparison of measured trace gas time series with model calculations shows a gap in the understanding of radical chemistry in the MVK oxidation scheme. The possibility of unimolecular isomerization reactions were investigated by means of quantum-chemical calculations.
This article is included in the Encyclopedia of Geosciences
Martin G. Schultz, Scarlet Stadtler, Sabine Schröder, Domenico Taraborrelli, Bruno Franco, Jonathan Krefting, Alexandra Henrot, Sylvaine Ferrachat, Ulrike Lohmann, David Neubauer, Colombe Siegenthaler-Le Drian, Sebastian Wahl, Harri Kokkola, Thomas Kühn, Sebastian Rast, Hauke Schmidt, Philip Stier, Doug Kinnison, Geoffrey S. Tyndall, John J. Orlando, and Catherine Wespes
Geosci. Model Dev., 11, 1695–1723, https://doi.org/10.5194/gmd-11-1695-2018, https://doi.org/10.5194/gmd-11-1695-2018, 2018
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The chemistry–climate model ECHAM-HAMMOZ contains a detailed representation of tropospheric and stratospheric reactive chemistry and state-of-the-art parameterizations of aerosols. It thus allows for detailed investigations of chemical processes in the climate system. Evaluation of the model with various observational data yields good results, but the model has a tendency to produce too much OH in the tropics. This highlights the important interplay between atmospheric chemistry and dynamics.
This article is included in the Encyclopedia of Geosciences
Xuan Zhang, John Ortega, Yuanlong Huang, Stephen Shertz, Geoffrey S. Tyndall, and John J. Orlando
Atmos. Meas. Tech., 11, 2537–2551, https://doi.org/10.5194/amt-11-2537-2018, https://doi.org/10.5194/amt-11-2537-2018, 2018
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We present the development and characterization of the NCAR Atmospheric Simulation Chamber, which is operated in steady state continuous
flow mode for simulating atmospheric daytime and nighttime chemistry over chemical regimes not accessible in traditional static chamber
experiments. We focus on establishing an
This article is included in the Encyclopedia of Geosciences
intermediate NOregime characterized by a constant steady-state NO level ranging from tens of ppt to a few ppb in the chamber.
Mike J. Newland, Andrew R. Rickard, Tomás Sherwen, Mathew J. Evans, Luc Vereecken, Amalia Muñoz, Milagros Ródenas, and William J. Bloss
Atmos. Chem. Phys., 18, 6095–6120, https://doi.org/10.5194/acp-18-6095-2018, https://doi.org/10.5194/acp-18-6095-2018, 2018
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Stabilised Criegee intermediates (SCIs) are formed in the reaction of alkenes with ozone, both of which are ubiquitous throughout the troposphere. We determine the fate and global distribution of SCI from monoterpene ozonolysis. One major fate of SCI is reaction with H2O, but for a fraction of SCIs, unimolecular reactions dominate. Concentrations of SCIs are high enough regionally to play a key role in the conversion of sulfur dioxide to aerosol, affecting air quality and climate.
This article is included in the Encyclopedia of Geosciences
Felix A. Mackenzie-Rae, Helen J. Wallis, Andrew R. Rickard, Kelly L. Pereira, Sandra M. Saunders, Xinming Wang, and Jacqueline F. Hamilton
Atmos. Chem. Phys., 18, 4673–4693, https://doi.org/10.5194/acp-18-4673-2018, https://doi.org/10.5194/acp-18-4673-2018, 2018
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Native to Australasia, the remarkable adaptability, rapid growth rates and high quality wood of eucalypt trees has led to them the most widely planted hardwood forest trees in the world. In contrast to boreal and tropical forests, there has been little study of aerosol formation in these regions. Here, we study the secondary organic aerosol formation from the very fast reaction of α-phellandrene, emitted from eucalypts, and identify key products and reaction pathways.
This article is included in the Encyclopedia of Geosciences
Jacob T. Shaw, Richard T. Lidster, Danny R. Cryer, Noelia Ramirez, Fiona C. Whiting, Graham A. Boustead, Lisa K. Whalley, Trevor Ingham, Andrew R. Rickard, Rachel E. Dunmore, Dwayne E. Heard, Ally C. Lewis, Lucy J. Carpenter, Jacqui F. Hamilton, and Terry J. Dillon
Atmos. Chem. Phys., 18, 4039–4054, https://doi.org/10.5194/acp-18-4039-2018, https://doi.org/10.5194/acp-18-4039-2018, 2018
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The lifetime of a chemical in the atmosphere is largely governed by the rate of its reaction with the hydroxyl radical (OH). Measurements of rates for many of the thousands of identified volatile organic compounds (VOCs) have yet to be determined experimentally. We have developed a new technique for the rapid determination of gas-phase rate coefficients for the simultaneous reactions between multiple VOCs and OH. The method is tasted across a range of scenarios and is used to derive new values.
This article is included in the Encyclopedia of Geosciences
Ganglin Lv, Xiao Sui, Jianmin Chen, Rohan Jayaratne, and Abdelwahid Mellouki
Atmos. Chem. Phys., 18, 2243–2258, https://doi.org/10.5194/acp-18-2243-2018, https://doi.org/10.5194/acp-18-2243-2018, 2018
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We conducted an investigation of new particle formation (NPF) at the summit of Mt. Tai, eastern China, based on simultaneous measurements of particle size distribution, meteorological parameters, gaseous species, mass concentration, and chemical composition of PM2.5. The general characteristics, favorable conditions, and potential precursor species of NPF events are discussed. An in-depth study of NPF on Mt. Tai is important for understanding the effect of particles on air quality.
This article is included in the Encyclopedia of Geosciences
Daniel R. Moon, Giorgio S. Taverna, Clara Anduix-Canto, Trevor Ingham, Martyn P. Chipperfield, Paul W. Seakins, Maria-Teresa Baeza-Romero, and Dwayne E. Heard
Atmos. Chem. Phys., 18, 327–338, https://doi.org/10.5194/acp-18-327-2018, https://doi.org/10.5194/acp-18-327-2018, 2018
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One geoengineering mitigation strategy for global temperature rises is to inject particles into the stratosphere to scatter solar radiation back to space. However, the injection of such particles must not perturb ozone. We measured the rate of uptake of HO2 radicals, an important stratospheric intermediate, onto TiO2 particles. Using the atmospheric model TOMCAT, we showed that surface reactions between HO2 and TiO2 would have a negligible effect on stratospheric concentrations of HO2 and ozone.
This article is included in the Encyclopedia of Geosciences
Lavinia Onel, Alexander Brennan, Michele Gianella, Grace Ronnie, Ana Lawry Aguila, Gus Hancock, Lisa Whalley, Paul W. Seakins, Grant A. D. Ritchie, and Dwayne E. Heard
Atmos. Meas. Tech., 10, 4877–4894, https://doi.org/10.5194/amt-10-4877-2017, https://doi.org/10.5194/amt-10-4877-2017, 2017
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Hydroperoxy (HO2) radicals are key intermediates participating in a rapid chemical cycling at the centre of the tropospheric oxidation. Fluorescence assay by gas expansion (FAGE) technique is the most commonly used for the HO2 measurements in the atmosphere. However, FAGE is an indirect technique, requiring calibration. This work finds a good agreement between the indirect FAGE method and the direct cavity ring-down spectroscopy method and hence validates FAGE and the FAGE calibration method.
This article is included in the Encyclopedia of Geosciences
Lavinia Onel, Alexander Brennan, Paul W. Seakins, Lisa Whalley, and Dwayne E. Heard
Atmos. Meas. Tech., 10, 3985–4000, https://doi.org/10.5194/amt-10-3985-2017, https://doi.org/10.5194/amt-10-3985-2017, 2017
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Methyl peroxy (CH3O2) radicals are the most abundant organic peroxy radical species and are critical intermediates in rapid chemical cycling at the heart of tropospheric oxidation. Despite their importance, at present CH3O2 radicals are not specifically measured in the atmosphere by any direct or indirect method. This work presents a new method for the selective and sensitive detection of CH3O2 radicals and its use for the measurement of CH3O2 in the atmospheric simulation chamber HIRAC.
This article is included in the Encyclopedia of Geosciences
Hendrik Fuchs, Anna Novelli, Michael Rolletter, Andreas Hofzumahaus, Eva Y. Pfannerstill, Stephan Kessel, Achim Edtbauer, Jonathan Williams, Vincent Michoud, Sebastien Dusanter, Nadine Locoge, Nora Zannoni, Valerie Gros, Francois Truong, Roland Sarda-Esteve, Danny R. Cryer, Charlotte A. Brumby, Lisa K. Whalley, Daniel Stone, Paul W. Seakins, Dwayne E. Heard, Coralie Schoemaecker, Marion Blocquet, Sebastien Coudert, Sebastien Batut, Christa Fittschen, Alexander B. Thames, William H. Brune, Cheryl Ernest, Hartwig Harder, Jennifer B. A. Muller, Thomas Elste, Dagmar Kubistin, Stefanie Andres, Birger Bohn, Thorsten Hohaus, Frank Holland, Xin Li, Franz Rohrer, Astrid Kiendler-Scharr, Ralf Tillmann, Robert Wegener, Zhujun Yu, Qi Zou, and Andreas Wahner
Atmos. Meas. Tech., 10, 4023–4053, https://doi.org/10.5194/amt-10-4023-2017, https://doi.org/10.5194/amt-10-4023-2017, 2017
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Hydroxyl radical reactivity (k(OH)) is closely related to processes that lead to the formation of oxidised, secondary pollutants such as ozone and aerosol. In order to compare the performances of instruments measuring k(OH), experiments were conducted in the simulation chamber SAPHIR. Chemical conditions were chosen either to be representative of the atmosphere or to test potential limitations of instruments. Overall, the results show that instruments are capable of measuring k(OH).
This article is included in the Encyclopedia of Geosciences
Caihong Xu, Min Wei, Jianmin Chen, Chao Zhu, Jiarong Li, Ganglin Lv, Xianmang Xu, Lulu Zheng, Guodong Sui, Weijun Li, Bing Chen, Wenxing Wang, Qingzhu Zhang, Aijun Ding, and Abdelwahid Mellouki
Atmos. Chem. Phys., 17, 11247–11260, https://doi.org/10.5194/acp-17-11247-2017, https://doi.org/10.5194/acp-17-11247-2017, 2017
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Fungi are ubiquitous throughout the near-surface atmosphere, where they represent an important component of primary biological aerosol particles. The diversity and composition of the fungal communities varied over the different seasons between the fine (PM2.5) and submicron (PM1) particles at the summit of Mt. Tai located in the North China Plain, China. This work may serve as an important reference for the fungal contribution to primary biological aerosol particles.
This article is included in the Encyclopedia of Geosciences
Stephan Keßel, David Cabrera-Perez, Abraham Horowitz, Patrick R. Veres, Rolf Sander, Domenico Taraborrelli, Maria Tucceri, John N. Crowley, Andrea Pozzer, Christof Stönner, Luc Vereecken, Jos Lelieveld, and Jonathan Williams
Atmos. Chem. Phys., 17, 8789–8804, https://doi.org/10.5194/acp-17-8789-2017, https://doi.org/10.5194/acp-17-8789-2017, 2017
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In this study we identify an often overlooked stable oxide of carbon, namely carbon suboxide (C3O2), in ambient air. We have made C3O2 and in the laboratory determined its absorption cross section data and the rate of reaction with two important atmospheric oxidants, OH and O3. By incorporating known sources and sinks in a global model we have generated a first global picture of the distribution of this species in the atmosphere.
This article is included in the Encyclopedia of Geosciences
Anna Novelli, Korbinian Hens, Cheryl Tatum Ernest, Monica Martinez, Anke C. Nölscher, Vinayak Sinha, Pauli Paasonen, Tuukka Petäjä, Mikko Sipilä, Thomas Elste, Christian Plass-Dülmer, Gavin J. Phillips, Dagmar Kubistin, Jonathan Williams, Luc Vereecken, Jos Lelieveld, and Hartwig Harder
Atmos. Chem. Phys., 17, 7807–7826, https://doi.org/10.5194/acp-17-7807-2017, https://doi.org/10.5194/acp-17-7807-2017, 2017
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The ambient concentration of stabilised Criegee intermediates (SCIs) was estimated for two
environments using field data. The low concentrations predicted indicate that SCIs are
unlikely to have a large impact on atmospheric chemistry. Concurrent measurements of an OH background signal using the Mainz IPI-LIF-FAGE instrument were found to be consistent with the chemistry of SCIs during the measurement campaigns.
This article is included in the Encyclopedia of Geosciences
David O. Topping, James Allan, M. Rami Alfarra, and Bernard Aumont
Geosci. Model Dev., 10, 2365–2377, https://doi.org/10.5194/gmd-10-2365-2017, https://doi.org/10.5194/gmd-10-2365-2017, 2017
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Our ability to model the chemical and thermodynamic processes that lead to secondary organic aerosol (SOA) formation is thought to be hampered by the complexity of the system. In this proof of concept study, the ability to train supervised methods to predict electron impact ionisation (EI) mass spectra for the AMS is evaluated to facilitate improved model evaluation. The study demonstrates the use of a methodology that would be improved with more training data and data from simple mixed systems.
This article is included in the Encyclopedia of Geosciences
Sebastian Laufs, Mathieu Cazaunau, Patrick Stella, Ralf Kurtenbach, Pierre Cellier, Abdelwahid Mellouki, Benjamin Loubet, and Jörg Kleffmann
Atmos. Chem. Phys., 17, 6907–6923, https://doi.org/10.5194/acp-17-6907-2017, https://doi.org/10.5194/acp-17-6907-2017, 2017
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Sources of nitrous acid (HONO), a major precursor of the OH radical, are still under controversial discussion. Since mainly ground surface sources have been proposed, HONO fluxes were measured above an agricultural field. Positive daytime fluxes were observed which showed strong correlation with the product of the NO2 concentration and J(NO2). These results indicate HONO formation by photosensitized heterogeneous conversion of NO2 on soil surfaces as observed in recent laboratory studies.
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Martin Kaminski, Hendrik Fuchs, Ismail-Hakki Acir, Birger Bohn, Theo Brauers, Hans-Peter Dorn, Rolf Häseler, Andreas Hofzumahaus, Xin Li, Anna Lutz, Sascha Nehr, Franz Rohrer, Ralf Tillmann, Luc Vereecken, Robert Wegener, and Andreas Wahner
Atmos. Chem. Phys., 17, 6631–6650, https://doi.org/10.5194/acp-17-6631-2017, https://doi.org/10.5194/acp-17-6631-2017, 2017
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Monoterpenes emitted by trees are among the volatile organic compounds with the highest global emission rates. The atmospheric degradation of the monoterpene β-pinene was investigated in the atmosphere simulation chamber SAPHIR in Jülich under low NOx and atmospheric β-pinene concentrations. While the budget of OH was balanced, both OH and HO2 concentrations were underestimated in the simulation results. These observations suggest the existence of unaccounted sources of HO2.
This article is included in the Encyclopedia of Geosciences
Chunlin Li, Yunjie Hu, Fei Zhang, Jianmin Chen, Zhen Ma, Xingnan Ye, Xin Yang, Lin Wang, Xingfu Tang, Renhe Zhang, Mu Mu, Guihua Wang, Haidong Kan, Xinming Wang, and Abdelwahid Mellouki
Atmos. Chem. Phys., 17, 4957–4988, https://doi.org/10.5194/acp-17-4957-2017, https://doi.org/10.5194/acp-17-4957-2017, 2017
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Detailed emission factors for smoke particulate species in PM2.5 and PM1.0 were derived from laboratory simulation of crop straw burning using aerosol chamber systems. Based on this, emissions for crop residue field burning in China were calculated and characterized with respect to five different burning scenarios. Moreover, health effects and health-related economic loss from smoke particle exposure were assessed; a practical emission control policy for agricultural field burning was proposed.
This article is included in the Encyclopedia of Geosciences
Haiyan Li, Qi Zhang, Qiang Zhang, Chunrong Chen, Litao Wang, Zhe Wei, Shan Zhou, Caroline Parworth, Bo Zheng, Francesco Canonaco, André S. H. Prévôt, Ping Chen, Hongliang Zhang, Timothy J. Wallington, and Kebin He
Atmos. Chem. Phys., 17, 4751–4768, https://doi.org/10.5194/acp-17-4751-2017, https://doi.org/10.5194/acp-17-4751-2017, 2017
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The sources and aerosol evolution processes of severe pollution episodes were investigated in Handan during wintertime using real-time measurements. An in-depth analysis of the data uncovered that primary emissions from coal combustion and biomass burning together with secondary formation of sulfate (mainly from SO2 emitted by coal combustion) are important driving factors for haze evolution. Our findings provide useful insights into air pollution control in heavily polluted regions.
This article is included in the Encyclopedia of Geosciences
Camille Mouchel-Vallon, Laurent Deguillaume, Anne Monod, Hélène Perroux, Clémence Rose, Giovanni Ghigo, Yoann Long, Maud Leriche, Bernard Aumont, Luc Patryl, Patrick Armand, and Nadine Chaumerliac
Geosci. Model Dev., 10, 1339–1362, https://doi.org/10.5194/gmd-10-1339-2017, https://doi.org/10.5194/gmd-10-1339-2017, 2017
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The Cloud Explicit Physico-chemical Scheme (CLEPS 1.0) describes oxidation of water-soluble organic compounds resulting from isoprene oxidation. It is based on structure activity relationships (SARs) (global rate constants and branching ratios for HO• abstraction and addition) and GROMHE SAR (Henry's law constants for undocumented species). It is coupled to the MCM gas phase mechanism and is included in a model using the DSMACC model and KPP to analyze experimental and field data.
This article is included in the Encyclopedia of Geosciences
Chelsea R. Thompson, Paul B. Shepson, Jin Liao, L. Greg Huey, Chris Cantrell, Frank Flocke, and John Orlando
Atmos. Chem. Phys., 17, 3401–3421, https://doi.org/10.5194/acp-17-3401-2017, https://doi.org/10.5194/acp-17-3401-2017, 2017
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The generally accepted mechanism leading to ozone depletion events in the Arctic assumes efficient gas-phase recycling of bromine atoms, such that the rate of ozone depletion has often been estimated as the rate that Br atoms regenerate through gas-phase BrO + BrO and BrO + ClO reactions. Using a large suite of data from the OASIS2009 campaign, our modeling results show that the gas-phase regeneration of Br is less efficient than expected and that heterogeneous recycling on surfaces is critical.
This article is included in the Encyclopedia of Geosciences
Lindsay E. Hatch, Robert J. Yokelson, Chelsea E. Stockwell, Patrick R. Veres, Isobel J. Simpson, Donald R. Blake, John J. Orlando, and Kelley C. Barsanti
Atmos. Chem. Phys., 17, 1471–1489, https://doi.org/10.5194/acp-17-1471-2017, https://doi.org/10.5194/acp-17-1471-2017, 2017
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The most comprehensive database of gaseous biomass burning emissions to date was compiled. Four complementary instruments were deployed together during laboratory fires. The results generally compared within experimental uncertainty and highlighted that a range of measurement approaches are required for adequate characterization of smoke composition. Observed compounds were binned based on volatility, and priority recommendations were made to improve secondary organic aerosol predictions.
This article is included in the Encyclopedia of Geosciences
Likun Xue, Rongrong Gu, Tao Wang, Xinfeng Wang, Sandra Saunders, Donald Blake, Peter K. K. Louie, Connie W. Y. Luk, Isobel Simpson, Zheng Xu, Zhe Wang, Yuan Gao, Shuncheng Lee, Abdelwahid Mellouki, and Wenxing Wang
Atmos. Chem. Phys., 16, 9891–9903, https://doi.org/10.5194/acp-16-9891-2016, https://doi.org/10.5194/acp-16-9891-2016, 2016
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The chemical budgets and principal sources of ROx and NO3 radicals during a multi-day photochemical smog episode in Hong Kong are elucidated by an observation-constrained MCM model. NO3 was shown to be an important oxidant even during daytime in a pollution case when high aerosol loading attenuated the solar irradiation. This study suggests the potential important role of daytime NO3 chemistry in polluted atmospheres under conditions with the co-existence of abundant O3, NO2, VOCs, and aerosols.
This article is included in the Encyclopedia of Geosciences
Daniel Stone, Lisa K. Whalley, Trevor Ingham, Peter M. Edwards, Danny R. Cryer, Charlotte A. Brumby, Paul W. Seakins, and Dwayne E. Heard
Atmos. Meas. Tech., 9, 2827–2844, https://doi.org/10.5194/amt-9-2827-2016, https://doi.org/10.5194/amt-9-2827-2016, 2016
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OH reactivity is the total pseudo-first-order loss rate coefficient describing the removal of OH radicals to all sinks in the atmosphere. Measurements of ambient OH reactivity can be used to discover the extent to which measured OH sinks contribute to the total OH loss rate. In this work, we describe the design and characterisation of an instrument to measure OH reactivity using laser flash photolysis coupled to laser-induced fluorescence (LFP-LIF) spectroscopy.
This article is included in the Encyclopedia of Geosciences
Chris Reed, Charlotte A. Brumby, Leigh R. Crilley, Louisa J. Kramer, William J. Bloss, Paul W. Seakins, James D. Lee, and Lucy J. Carpenter
Atmos. Meas. Tech., 9, 2483–2495, https://doi.org/10.5194/amt-9-2483-2016, https://doi.org/10.5194/amt-9-2483-2016, 2016
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A new method of measuring nitrous acid (HONO), a potent mediator of air quality in the atmosphere as well as an important indoor pollutant, is presented. The new method relies on simple, proven techniques already widely applied to other atmospheric compounds. The technique can be retrofitted to existing analysers at minimal cost, or developed into instruments capable of very fast measurement which allow for more complex analysis of the behaviour of HONO.
This article is included in the Encyclopedia of Geosciences
Frank A. F. Winiberg, Terry J. Dillon, Stephanie C. Orr, Christoph B. M Groß, Iustinian Bejan, Charlotte A. Brumby, Matthew J. Evans, Shona C. Smith, Dwayne E. Heard, and Paul W. Seakins
Atmos. Chem. Phys., 16, 4023–4042, https://doi.org/10.5194/acp-16-4023-2016, https://doi.org/10.5194/acp-16-4023-2016, 2016
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OH radicals are important intermediates in the atmosphere, and the high concentrations observed in tropical regions are yet to be fully explained. Radical-radical reactions such as the title reaction can contribute to OH formation. This is the most fully comprehensive study of the CH3C(O)O2 + HO2 reaction with direct observation of products in all reaction channels. The implications of the new measurements on OH, PAN and NOx concentrations are considered via global models.
This article is included in the Encyclopedia of Geosciences
Renee C. McVay, Xuan Zhang, Bernard Aumont, Richard Valorso, Marie Camredon, Yuyi S. La, Paul O. Wennberg, and John H. Seinfeld
Atmos. Chem. Phys., 16, 2785–2802, https://doi.org/10.5194/acp-16-2785-2016, https://doi.org/10.5194/acp-16-2785-2016, 2016
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Secondary organic aerosol (SOA) affects climate change, human health, and cloud formation. We examine SOA formation from the biogenic hydrocarbon α-pinene and observe unexpected experimental results that run contrary to model predictions. Various processes are explored via modeling to rationalize the observations. The paper identifies the importance of further constraining via experiments various steps in the chemical mechanism in order to accurately predict SOA worldwide.
This article is included in the Encyclopedia of Geosciences
David Topping, Mark Barley, Michael K. Bane, Nicholas Higham, Bernard Aumont, Nicholas Dingle, and Gordon McFiggans
Geosci. Model Dev., 9, 899–914, https://doi.org/10.5194/gmd-9-899-2016, https://doi.org/10.5194/gmd-9-899-2016, 2016
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In this paper we describe the development and application of a new web-based and open-source facility, UManSysProp (http://umansysprop .seaes.manchester.ac.uk), for automating predictions of molecular and atmospheric aerosol properties. Current facilities include pure component vapour pressures, critical properties, and sub-cooled densities of organic molecules; activity coefficient predictions for mixed inorganic-organic liquid systems; hygroscopic growth factors and CCN activation potential.
This article is included in the Encyclopedia of Geosciences
Wei Deng, Qihou Hu, Tengyu Liu, Xinming Wang, Yanli Zhang, Xiang Ding, Yele Sun, Xinhui Bi, Jianzhen Yu, Weiqiang Yang, Xinyu Huang, Zhou Zhang, Zhonghui Huang, Quanfu He, A. Mellouki, and Christian George
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2016-50, https://doi.org/10.5194/acp-2016-50, 2016
Revised manuscript not accepted
Y. S. La, M. Camredon, P. J. Ziemann, R. Valorso, A. Matsunaga, V. Lannuque, J. Lee-Taylor, A. Hodzic, S. Madronich, and B. Aumont
Atmos. Chem. Phys., 16, 1417–1431, https://doi.org/10.5194/acp-16-1417-2016, https://doi.org/10.5194/acp-16-1417-2016, 2016
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The potential impact of chamber walls on the loss of gaseous organic species and secondary organic aerosol (SOA) formation has been explored using the GECKO-A modeling tool, which explicitly represents SOA formation and gas-wall partitioning. The model was compared with 41 smog chamber experiments of SOA formation under OH oxidation of alkane and alkene serie. The organic vapor loss to the chamber walls is found to affect SOA yields as well as the composition of the gas and the particle phase.
This article is included in the Encyclopedia of Geosciences
M. E. Jenkin, J. C. Young, and A. R. Rickard
Atmos. Chem. Phys., 15, 11433–11459, https://doi.org/10.5194/acp-15-11433-2015, https://doi.org/10.5194/acp-15-11433-2015, 2015
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Atmospheric isoprene oxidation has an important effect on the formation of pollutants such as ozone and particles. A reliable representation is an essential component of climate change/air quality models. Systematic updates to the detailed chemistry in the MCM are described, with reference to recently reported kinetic/mechanistic data. Results of box model calculations are used to illustrate the impacts of the updates, with particular focus on the key atmospheric cycles involving HOx and NOx.
This article is included in the Encyclopedia of Geosciences
J.-M. Yoo, M.-J. Jeong, D. Kim, W. R. Stockwell, J.-H. Yang, H.-W. Shin, M.-I. Lee, C.-K. Song, and S.-D. Lee
Atmos. Chem. Phys., 15, 10857–10885, https://doi.org/10.5194/acp-15-10857-2015, https://doi.org/10.5194/acp-15-10857-2015, 2015
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Major air pollutants (O3, NO2, SO2, CO, PM10, and VOCs) with long-term records from a dense observation network over Korea were extensively analyzed with land-use types, classified by Korean government, consistent with satellite-observed land covers. The weekly cycles of the pollutant showed different behaviors with the types. Regardless of land-use types, ozone has an increasing trend, while the other pollutants have decreasing trends. Most areas in Korea were VOCs-limited for ozone chemistry.
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K. D. Custard, C. R. Thompson, K. A. Pratt, P B. Shepson, J. Liao, L. G. Huey, J. J. Orlando, A. J. Weinheimer, E. Apel, S. R. Hall, F. Flocke, L. Mauldin, R. S. Hornbrook, D. Pöhler, S. General, J. Zielcke, W. R. Simpson, U. Platt, A. Fried, P. Weibring, B. C. Sive, K. Ullmann, C. Cantrell, D. J. Knapp, and D. D. Montzka
Atmos. Chem. Phys., 15, 10799–10809, https://doi.org/10.5194/acp-15-10799-2015, https://doi.org/10.5194/acp-15-10799-2015, 2015
R. E. Dunmore, J. R. Hopkins, R. T. Lidster, J. D. Lee, M. J. Evans, A. R. Rickard, A. C. Lewis, and J. F. Hamilton
Atmos. Chem. Phys., 15, 9983–9996, https://doi.org/10.5194/acp-15-9983-2015, https://doi.org/10.5194/acp-15-9983-2015, 2015
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Technological shifts between fuel sources have had unexpected impacts on atmospheric composition and these significant changes can go undetected if source-specific monitoring infrastructure is not in place. We present chemically comprehensive, continuous measurements of organic compounds in a developed megacity (London), that show diesel-related hydrocarbons can dominate reactive carbon and ozone formation potential, highlighting a serious underestimation of this source in emission inventories.
This article is included in the Encyclopedia of Geosciences
C. R. Thompson, P. B. Shepson, J. Liao, L. G. Huey, E. C. Apel, C. A. Cantrell, F. Flocke, J. Orlando, A. Fried, S. R. Hall, R. S. Hornbrook, D. J. Knapp, R. L. Mauldin III, D. D. Montzka, B. C. Sive, K. Ullmann, P. Weibring, and A. Weinheimer
Atmos. Chem. Phys., 15, 9651–9679, https://doi.org/10.5194/acp-15-9651-2015, https://doi.org/10.5194/acp-15-9651-2015, 2015
M. J. Newland, A. R. Rickard, L. Vereecken, A. Muñoz, M. Ródenas, and W. J. Bloss
Atmos. Chem. Phys., 15, 9521–9536, https://doi.org/10.5194/acp-15-9521-2015, https://doi.org/10.5194/acp-15-9521-2015, 2015
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Stabilised Criegee intermediates (SCIs) are formed through alkene-ozone reactions, which occur throughout the atmospheric boundary layer. Recent direct laboratory studies have shown that SCI react rapidly with SO2, NO2 and other trace gases, affecting air quality and climate. We present experimental data from the EUPHORE atmospheric simulation chamber, in which we determine the effects of the ozonolysis of isoprene, on the oxidation of SO2 as a function of H2O and dimethyl sulfide concentration.
This article is included in the Encyclopedia of Geosciences
A. Hodzic, S. Madronich, P. S. Kasibhatla, G. Tyndall, B. Aumont, J. L. Jimenez, J. Lee-Taylor, and J. Orlando
Atmos. Chem. Phys., 15, 9253–9269, https://doi.org/10.5194/acp-15-9253-2015, https://doi.org/10.5194/acp-15-9253-2015, 2015
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Our study combines process and global chemistry modeling to investigate the potential effect of gas- and particle-phase organic photolysis reactions on the formation and lifetime of secondary organic aerosols (SOAs). Photolysis of the oxidation intermediates that partition between gas and particle phases to form SOA is not included in 3D models. Our results suggest that exposure to UV light can suppress the formation of SOA or even lead to its substantial loss (comparable to wet deposition).
This article is included in the Encyclopedia of Geosciences
B. Ervens, P. Renard, S. Tlili, S. Ravier, J.-L. Clément, and A. Monod
Atmos. Chem. Phys., 15, 9109–9127, https://doi.org/10.5194/acp-15-9109-2015, https://doi.org/10.5194/acp-15-9109-2015, 2015
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A detailed chemical mechanism is developed based on laboratory studies that predicts the formation of high molecular weight compounds in the aqueous phase of atmospheric aerosol particles. Model simulations using this mechanism for atmospheric conditions show that these pathways are likely not a substantial source of particle mass, unless unidentified precursors for these compounds exist that were not taken into account so far and/or the solubility of oxygen in aerosol water is overestimated.
This article is included in the Encyclopedia of Geosciences
K. P. Wyche, P. S. Monks, K. L. Smallbone, J. F. Hamilton, M. R. Alfarra, A. R. Rickard, G. B. McFiggans, M. E. Jenkin, W. J. Bloss, A. C. Ryan, C. N. Hewitt, and A. R. MacKenzie
Atmos. Chem. Phys., 15, 8077–8100, https://doi.org/10.5194/acp-15-8077-2015, https://doi.org/10.5194/acp-15-8077-2015, 2015
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This paper describes a new ensemble methodology for the statistical analysis of atmospheric gas- & particle-phase composition data sets. The methodology reduces the huge amount of data derived from many chamber experiments to show that organic reactivity & resultant particle formation can be mapped into unique clusters in statistical space. The model generated is used to map more realistic plant mesocosm oxidation data, the projection of which gives insight into reactive pathways & precursors.
This article is included in the Encyclopedia of Geosciences
R. Thalman, M. T. Baeza-Romero, S. M. Ball, E. Borrás, M. J. S. Daniels, I. C. A. Goodall, S. B. Henry, T. Karl, F. N. Keutsch, S. Kim, J. Mak, P. S. Monks, A. Muñoz, J. Orlando, S. Peppe, A. R. Rickard, M. Ródenas, P. Sánchez, R. Seco, L. Su, G. Tyndall, M. Vázquez, T. Vera, E. Waxman, and R. Volkamer
Atmos. Meas. Tech., 8, 1835–1862, https://doi.org/10.5194/amt-8-1835-2015, https://doi.org/10.5194/amt-8-1835-2015, 2015
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Measurements of α-dicarbonyl compounds, like glyoxal (CHOCHO) and methyl glyoxal (CH3C(O)CHO), are informative about the rate of hydrocarbon oxidation, oxidative capacity, and secondary organic aerosol (SOA) formation in the atmosphere. We have compared nine instruments and seven techniques to measure α-dicarbonyl, using simulation chamber facilities in the US and Europe. We assess our understanding of calibration, precision, accuracy and detection limits, as well as possible sampling biases.
This article is included in the Encyclopedia of Geosciences
B. Yuan, P. R. Veres, C. Warneke, J. M. Roberts, J. B. Gilman, A. Koss, P. M. Edwards, M. Graus, W. C. Kuster, S.-M. Li, R. J. Wild, S. S. Brown, W. P. Dubé, B. M. Lerner, E. J. Williams, J. E. Johnson, P. K. Quinn, T. S. Bates, B. Lefer, P. L. Hayes, J. L. Jimenez, R. J. Weber, R. Zamora, B. Ervens, D. B. Millet, B. Rappenglück, and J. A. de Gouw
Atmos. Chem. Phys., 15, 1975–1993, https://doi.org/10.5194/acp-15-1975-2015, https://doi.org/10.5194/acp-15-1975-2015, 2015
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In this work, secondary formation of formic acid at an urban site and a site in an oil and gas production region is studied. We investigated various gas phase formation pathways of formic acid, including those recently proposed, using a box model. The contributions from aerosol-related processes, fog events and air-snow exchange to formic acid are also quantified.
This article is included in the Encyclopedia of Geosciences
F. A. F. Winiberg, S. C. Smith, I. Bejan, C. A. Brumby, T. Ingham, T. L. Malkin, S. C. Orr, D. E. Heard, and P. W. Seakins
Atmos. Meas. Tech., 8, 523–540, https://doi.org/10.5194/amt-8-523-2015, https://doi.org/10.5194/amt-8-523-2015, 2015
C. Denjean, P. Formenti, B. Picquet-Varrault, M. Camredon, E. Pangui, P. Zapf, Y. Katrib, C. Giorio, A. Tapparo, B. Temime-Roussel, A. Monod, B. Aumont, and J. F. Doussin
Atmos. Chem. Phys., 15, 883–897, https://doi.org/10.5194/acp-15-883-2015, https://doi.org/10.5194/acp-15-883-2015, 2015
J. Lee-Taylor, A. Hodzic, S. Madronich, B. Aumont, M. Camredon, and R. Valorso
Atmos. Chem. Phys., 15, 595–615, https://doi.org/10.5194/acp-15-595-2015, https://doi.org/10.5194/acp-15-595-2015, 2015
J. W. Taylor, J. D. Allan, G. Allen, H. Coe, P. I. Williams, M. J. Flynn, M. Le Breton, J. B. A. Muller, C. J. Percival, D. Oram, G. Forster, J. D. Lee, A. R. Rickard, M. Parrington, and P. I. Palmer
Atmos. Chem. Phys., 14, 13755–13771, https://doi.org/10.5194/acp-14-13755-2014, https://doi.org/10.5194/acp-14-13755-2014, 2014
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We present a case study of BC wet removal by examining aerosol properties in three biomass burning plumes, one of which passed through a precipitating cloud. Nucleation scavenging preferentially removed the largest and most coated BC-containing particles. Calculated single-scattering albedo (SSA) showed little variation, as a large number of non-BC particles were also present in the precipitation-affected plume.
This article is included in the Encyclopedia of Geosciences
R. T. Lidster, J. F. Hamilton, J. D. Lee, A. C. Lewis, J. R. Hopkins, S. Punjabi, A. R. Rickard, and J. C. Young
Atmos. Chem. Phys., 14, 6677–6693, https://doi.org/10.5194/acp-14-6677-2014, https://doi.org/10.5194/acp-14-6677-2014, 2014
C. Knote, A. Hodzic, J. L. Jimenez, R. Volkamer, J. J. Orlando, S. Baidar, J. Brioude, J. Fast, D. R. Gentner, A. H. Goldstein, P. L. Hayes, W. B. Knighton, H. Oetjen, A. Setyan, H. Stark, R. Thalman, G. Tyndall, R. Washenfelder, E. Waxman, and Q. Zhang
Atmos. Chem. Phys., 14, 6213–6239, https://doi.org/10.5194/acp-14-6213-2014, https://doi.org/10.5194/acp-14-6213-2014, 2014
K. L. Pereira, J. F. Hamilton, A. R. Rickard, W. J. Bloss, M. S. Alam, M. Camredon, A. Muñoz, M. Vázquez, E. Borrás, and M. Ródenas
Atmos. Chem. Phys., 14, 5349–5368, https://doi.org/10.5194/acp-14-5349-2014, https://doi.org/10.5194/acp-14-5349-2014, 2014
V. Michoud, A. Colomb, A. Borbon, K. Miet, M. Beekmann, M. Camredon, B. Aumont, S. Perrier, P. Zapf, G. Siour, W. Ait-Helal, C. Afif, A. Kukui, M. Furger, J. C. Dupont, M. Haeffelin, and J. F. Doussin
Atmos. Chem. Phys., 14, 2805–2822, https://doi.org/10.5194/acp-14-2805-2014, https://doi.org/10.5194/acp-14-2805-2014, 2014
X. Pang, A. C. Lewis, A. R. Rickard, M. T. Baeza-Romero, T. J. Adams, S. M. Ball, M. J. S. Daniels, I. C. A. Goodall, P. S. Monks, S. Peppe, M. Ródenas García, P. Sánchez, and A. Muñoz
Atmos. Meas. Tech., 7, 373–389, https://doi.org/10.5194/amt-7-373-2014, https://doi.org/10.5194/amt-7-373-2014, 2014
L. K. Whalley, M. A. Blitz, M. Desservettaz, P. W. Seakins, and D. E. Heard
Atmos. Meas. Tech., 6, 3425–3440, https://doi.org/10.5194/amt-6-3425-2013, https://doi.org/10.5194/amt-6-3425-2013, 2013
G. Sarwar, J. Godowitch, B. H. Henderson, K. Fahey, G. Pouliot, W. T. Hutzell, R. Mathur, D. Kang, W. S. Goliff, and W. R. Stockwell
Atmos. Chem. Phys., 13, 9695–9712, https://doi.org/10.5194/acp-13-9695-2013, https://doi.org/10.5194/acp-13-9695-2013, 2013
Y. Xie, F. Paulot, W. P. L. Carter, C. G. Nolte, D. J. Luecken, W. T. Hutzell, P. O. Wennberg, R. C. Cohen, and R. W. Pinder
Atmos. Chem. Phys., 13, 8439–8455, https://doi.org/10.5194/acp-13-8439-2013, https://doi.org/10.5194/acp-13-8439-2013, 2013
M. Ammann, R. A. Cox, J. N. Crowley, M. E. Jenkin, A. Mellouki, M. J. Rossi, J. Troe, and T. J. Wallington
Atmos. Chem. Phys., 13, 8045–8228, https://doi.org/10.5194/acp-13-8045-2013, https://doi.org/10.5194/acp-13-8045-2013, 2013
M. Parrington, P. I. Palmer, A. C. Lewis, J. D. Lee, A. R. Rickard, P. Di Carlo, J. W. Taylor, J. R. Hopkins, S. Punjabi, D. E. Oram, G. Forster, E. Aruffo, S. J. Moller, S. J.-B. Bauguitte, J. D. Allan, H. Coe, and R. J. Leigh
Atmos. Chem. Phys., 13, 7321–7341, https://doi.org/10.5194/acp-13-7321-2013, https://doi.org/10.5194/acp-13-7321-2013, 2013
P. I. Palmer, M. Parrington, J. D. Lee, A. C. Lewis, A. R. Rickard, P. F. Bernath, T. J. Duck, D. L. Waugh, D. W. Tarasick, S. Andrews, E. Aruffo, L. J. Bailey, E. Barrett, S. J.-B. Bauguitte, K. R. Curry, P. Di Carlo, L. Chisholm, L. Dan, G. Forster, J. E. Franklin, M. D. Gibson, D. Griffin, D. Helmig, J. R. Hopkins, J. T. Hopper, M. E. Jenkin, D. Kindred, J. Kliever, M. Le Breton, S. Matthiesen, M. Maurice, S. Moller, D. P. Moore, D. E. Oram, S. J. O'Shea, R. C. Owen, C. M. L. S. Pagniello, S. Pawson, C. J. Percival, J. R. Pierce, S. Punjabi, R. M. Purvis, J. J. Remedios, K. M. Rotermund, K. M. Sakamoto, A. M. da Silva, K. B. Strawbridge, K. Strong, J. Taylor, R. Trigwell, K. A. Tereszchuk, K. A. Walker, D. Weaver, C. Whaley, and J. C. Young
Atmos. Chem. Phys., 13, 6239–6261, https://doi.org/10.5194/acp-13-6239-2013, https://doi.org/10.5194/acp-13-6239-2013, 2013
B. Ervens, Y. Wang, J. Eagar, W. R. Leaitch, A. M. Macdonald, K. T. Valsaraj, and P. Herckes
Atmos. Chem. Phys., 13, 5117–5135, https://doi.org/10.5194/acp-13-5117-2013, https://doi.org/10.5194/acp-13-5117-2013, 2013
C. Mouchel-Vallon, P. Bräuer, M. Camredon, R. Valorso, S. Madronich, H. Herrmann, and B. Aumont
Atmos. Chem. Phys., 13, 1023–1037, https://doi.org/10.5194/acp-13-1023-2013, https://doi.org/10.5194/acp-13-1023-2013, 2013
A. C. Lewis, M. J. Evans, J. R. Hopkins, S. Punjabi, K. A. Read, R. M. Purvis, S. J. Andrews, S. J. Moller, L. J. Carpenter, J. D. Lee, A. R. Rickard, P. I. Palmer, and M. Parrington
Atmos. Chem. Phys., 13, 851–867, https://doi.org/10.5194/acp-13-851-2013, https://doi.org/10.5194/acp-13-851-2013, 2013
V. Michoud, A. Kukui, M. Camredon, A. Colomb, A. Borbon, K. Miet, B. Aumont, M. Beekmann, R. Durand-Jolibois, S. Perrier, P. Zapf, G. Siour, W. Ait-Helal, N. Locoge, S. Sauvage, C. Afif, V. Gros, M. Furger, G. Ancellet, and J. F. Doussin
Atmos. Chem. Phys., 12, 11951–11974, https://doi.org/10.5194/acp-12-11951-2012, https://doi.org/10.5194/acp-12-11951-2012, 2012
Related subject area
Subject: Gases | Research Activity: Atmospheric Modelling and Data Analysis | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
Insights into ozone pollution control in urban areas by decoupling meteorological factors based on machine learning
Quantification of regional net CO2 flux errors in the Orbiting Carbon Observatory-2 (OCO-2) v10 model intercomparison project (MIP) ensemble using airborne measurements
Reactive nitrogen in and around the northeastern and mid-Atlantic US: sources, sinks, and connections with ozone
Preindustrial-to-present-day changes in atmospheric carbon monoxide: agreement and gaps between ice archives and global model reconstructions
Investigating processes influencing simulation of local Arctic wintertime anthropogenic pollution in Fairbanks, Alaska, during ALPACA-2022
Urban ozone formation and sensitivities to volatile chemical products, cooking emissions, and NOx upwind of and within two Los Angeles Basin cities
Causes of growing middle-to-upper tropospheric ozone over the northwest Pacific region
This article is included in the Encyclopedia of Geosciences
Impact of introducing electric vehicles on ground-level O3 and PM2.5 in the Greater Tokyo Area: yearly trends and the importance of changes in the urban heat island effect
A CO2–Δ14CO2 inversion setup for estimating European fossil CO2 emissions
Maximum ozone concentrations in the southwestern US and Texas: implications of the growing predominance of the background contribution
Derivation of atmospheric reaction mechanisms for volatile organic compounds by the SAPRC mechanism generation system (MechGen)
Seasonal, regional, and vertical characteristics of high-carbon-monoxide plumes along with their associated ozone anomalies, as seen by IAGOS between 2002 and 2019
The potential of drone observations to improve air quality predictions by 4D-Var
Process analysis of elevated concentrations of organic acids at Whiteface Mountain, New York
Ozone source attribution in polluted European areas during summer 2017 as simulated with MECO(n)
The atmospheric oxidizing capacity in China – Part 2: Sensitivity to emissions of primary pollutants
Role of chemical production and depositional losses on formaldehyde in the Community Regional Atmospheric Chemistry Multiphase Mechanism (CRACMM)
Review of source analyses of ambient volatile organic compounds considering reactive losses: methods of reducing loss effects, impacts of losses, and sources
Interpreting summertime hourly variation of NO2 columns with implications for geostationary satellite applications
An investigation into atmospheric nitrous acid (HONO) processes in South Korea
Performance evaluation of UKESM1 for surface ozone across the pan-tropics
Constraining light dependency in modeled emissions through comparison to observed biogenic volatile organic compound (BVOC) concentrations in a southeastern US forest
A global re-analysis of regionally resolved emissions and atmospheric mole fractions of SF6 for the period 2005–2021
Tropospheric ozone precursors: global and regional distributions, trends, and variability
The contribution of transport emissions to ozone mixing ratios and methane lifetime in 2015 and 2050 in the Shared Socioeconomic Pathways (SSPs)
Ether and ester formation from peroxy radical recombination: a qualitative reaction channel analysis
ACEIC: a comprehensive anthropogenic chlorine emission inventory for China
Impact of methane and other precursor emission reductions on surface ozone in Europe: scenario analysis using the European Monitoring and Evaluation Programme (EMEP) Meteorological Synthesizing Centre – West (MSC-W) model
Investigating the response of China’s surface ozone concentration to the future changes of multiple factors
Chemistry-climate feedback of atmospheric methane in a methane emission flux driven chemistry-climate model
Natural emissions of VOC and NOx over Africa constrained by TROPOMI HCHO and NO2 data using the MAGRITTEv1.1 model
Verifying national inventory-based combustion emissions of CO2 across the UK and mainland Europe using satellite observations of atmospheric CO and CO2
Revisiting the high tropospheric ozone over Southern Africa: overestimated biomass burning and underestimated anthropogenic emissions
Enhanced understanding of atmospheric blocking modulation on ozone dynamics within a high-resolution Earth system model
Estimating the variability of NOx emissions from Wuhan with TROPOMI NO2 data during 2018 to 2023
An improved estimate of inorganic iodine emissions from the ocean using a coupled surface microlayer box model
Technical note: A comparative study of chemistry schemes for volcanic sulfur dioxide in Lagrangian transport simulations: a case study of the 2019 Raikoke eruption
Impact of improved representation of volatile organic compound emissions and production of NOx reservoirs on modeled urban ozone production
The effect of different climate and air quality policies in China on in situ ozone production in Beijing
Assessing the relative impacts of satellite ozone and its precursor observations to improve global tropospheric ozone analysis using multiple chemical reanalysis systems
Evaluating present-day and future impacts of agricultural ammonia emissions on atmospheric chemistry and climate
Enhancing long-term trend simulation of the global tropospheric hydroxyl (TOH) and its drivers from 2005 to 2019: a synergistic integration of model simulations and satellite observations
Intercomparison of GEOS-Chem and CAM-chem tropospheric oxidant chemistry within the Community Earth System Model version 2 (CESM2)
Development of a detailed gaseous oxidation scheme of naphthalene for secondary organic aerosol (SOA) formation and speciation
Air pollution satellite-based CO2 emission inversion: system evaluation, sensitivity analysis, and future perspective
Anthropogenic emission controls reduce summertime ozone-temperature sensitivity in the United States
Large contributions of soil emissions to the atmospheric nitrogen budget and their impacts on air quality and temperature rise in North China
Why did ozone concentrations remain high during Shanghai's static management? A statistical and radical-chemistry perspective
Revising VOC emissions speciation improves the simulation of global background ethane and propane
Changes in South American surface ozone trends: exploring the influences of precursors and extreme events
Yuqing Qiu, Xin Li, Wenxuan Chai, Yi Liu, Mengdi Song, Xudong Tian, Qiaoli Zou, Wenjun Lou, Wangyao Zhang, Juan Li, and Yuanhang Zhang
Atmos. Chem. Phys., 25, 1749–1763, https://doi.org/10.5194/acp-25-1749-2025, https://doi.org/10.5194/acp-25-1749-2025, 2025
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The chemical reactions of ozone (O3) formation are related to meteorology and local emissions. Here, a random forest approach was used to eliminate the effects of meteorological factors (dispersion or transport) on O3 and its precursors. Variations in the sensitivity of O3 formation and the apportionment of emission sources were revealed after meteorological normalization. Our results suggest that meteorological variations should be considered when diagnosing O3 formation.
This article is included in the Encyclopedia of Geosciences
Jeongmin Yun, Junjie Liu, Brendan Byrne, Brad Weir, Lesley E. Ott, Kathryn McKain, Bianca C. Baier, Luciana V. Gatti, and Sebastien C. Biraud
Atmos. Chem. Phys., 25, 1725–1748, https://doi.org/10.5194/acp-25-1725-2025, https://doi.org/10.5194/acp-25-1725-2025, 2025
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This study quantifies errors in regional net surface–atmosphere CO2 flux estimates from an inverse model ensemble using airborne CO2 measurements. Our results show that flux error estimates based on observations significantly exceed those computed from the ensemble spread of flux estimates in regions with high fossil fuel emissions. This finding suggests the presence of systematic biases in the inversion estimates, associated with errors in the fossil fuel emissions common to all models.
This article is included in the Encyclopedia of Geosciences
Min Huang, Gregory R. Carmichael, Kevin W. Bowman, Isabelle De Smedt, Andreas Colliander, Michael H. Cosh, Sujay V. Kumar, Alex B. Guenther, Scott J. Janz, Ryan M. Stauffer, Anne M. Thompson, Niko M. Fedkin, Robert J. Swap, John D. Bolten, and Alicia T. Joseph
Atmos. Chem. Phys., 25, 1449–1476, https://doi.org/10.5194/acp-25-1449-2025, https://doi.org/10.5194/acp-25-1449-2025, 2025
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We use model simulations along with multiplatform, multidisciplinary observations and a range of analysis methods to estimate and understand the distributions, temporal changes, and impacts of reactive nitrogen and ozone over the most populous US region that has undergone significant environmental changes. Deposition, biogenic emissions, and extra-regional sources have been playing increasingly important roles in controlling pollutant budgets in this area as local anthropogenic emissions drop.
This article is included in the Encyclopedia of Geosciences
Xavier Faïn, Sophie Szopa, Vaishali Naïk, Patricia Martinerie, David M. Etheridge, Rachael H. Rhodes, Cathy M. Trudinger, Vasilii V. Petrenko, Kévin Fourteau, and Philip Place
Atmos. Chem. Phys., 25, 1105–1119, https://doi.org/10.5194/acp-25-1105-2025, https://doi.org/10.5194/acp-25-1105-2025, 2025
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Carbon monoxide (CO) plays a crucial role in the atmosphere's oxidizing capacity. In this study, we analyse how historical (1850–2014) [CO] outputs from state-of-the-art global chemistry–climate models over Greenland and Antarctica are able to capture both absolute values and trends recorded in multi-site ice archives. A disparity in [CO] growth rates emerges in the Northern Hemisphere between models and observations from 1920–1975 CE, possibly linked to uncertainties in CO emission factors.
This article is included in the Encyclopedia of Geosciences
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.
This article is included in the Encyclopedia of Geosciences
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.
This article is included in the Encyclopedia of Geosciences
Xiaodan Ma, Jianping Huang, Michaela I. Hegglin, Patrick Jöckel, and Tianliang Zhao
Atmos. Chem. Phys., 25, 943–958, https://doi.org/10.5194/acp-25-943-2025, https://doi.org/10.5194/acp-25-943-2025, 2025
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Our research explored changes in ozone levels in the northwest Pacific region over 30 years, revealing a significant increase in the middle-to-upper troposphere, especially during spring and summer. This rise is influenced by both stratospheric and tropospheric sources, which affect climate and air quality in East Asia. This work underscores the need for continued study to understand underlying mechanisms.
Hiroo Hata, Norifumi Mizushima, and Tomohiko Ihara
Atmos. Chem. Phys., 25, 1037–1061, https://doi.org/10.5194/acp-25-1037-2025, https://doi.org/10.5194/acp-25-1037-2025, 2025
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The introduction of battery electric vehicles (BEVs) is expected to reduce the primary air pollutants from vehicular exhaust and evaporative emissions while reducing the anthropogenic heat produced by vehicles, ultimately mitigating the urban heat island (UHI) effect. This study revealed the impact of introducing BEVs on the decrease in the UHI effect and the impact of BEVs on the formation of tropospheric ozone and fine particulate matter in the Greater Tokyo Area of Japan.
This article is included in the Encyclopedia of Geosciences
Carlos Gómez-Ortiz, Guillaume Monteil, Sourish Basu, and Marko Scholze
Atmos. Chem. Phys., 25, 397–424, https://doi.org/10.5194/acp-25-397-2025, https://doi.org/10.5194/acp-25-397-2025, 2025
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In this paper, we test new implementations of our inverse modeling tool to estimate the weekly and regional CO2 emissions from fossil fuels in Europe. We use synthetic atmospheric observations of CO2 and radiocarbon (14CO2) to trace emissions to their sources, while separating the natural and fossil CO2. Our tool accurately estimates fossil CO2 emissions in densely monitored regions like western/central Europe. This approach aids in developing strategies for reducing CO2 emissions.
This article is included in the Encyclopedia of Geosciences
David D. Parrish, Ian C. Faloona, and Richard G. Derwent
Atmos. Chem. Phys., 25, 263–289, https://doi.org/10.5194/acp-25-263-2025, https://doi.org/10.5194/acp-25-263-2025, 2025
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Observation-based estimates of contributions to maximum ozone (O3) concentrations show that background O3 can exceed the air quality standard of 70 ppb in the southwestern US, precluding standard attainment. Over the past 4 decades, US anthropogenic O3 has decreased by a factor of ~ 6.3, while wildfire contributions have increased, so that the background now dominates maximum concentrations, even in Los Angeles, and the occurrence of maximum O3 has shifted from the eastern to the western US.
This article is included in the Encyclopedia of Geosciences
William P. L. Carter, Jia Jiang, John J. Orlando, and Kelley C. Barsanti
Atmos. Chem. Phys., 25, 199–242, https://doi.org/10.5194/acp-25-199-2025, https://doi.org/10.5194/acp-25-199-2025, 2025
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This paper describes the scientific basis for gas-phase atmospheric chemical mechanisms derived using the SAPRC mechanism generation system, MechGen. It can derive mechanisms for most organic compounds with C, H, O, or N atoms, including initial reactions of organics with OH, O3, NO3, and O3P or by photolysis, as well as the reactions of the various types of intermediates that are formed. The paper includes a description of areas of uncertainty where additional research and updates are needed.
This article is included in the Encyclopedia of Geosciences
Thibaut Lebourgeois, Bastien Sauvage, Pawel Wolff, Béatrice Josse, Virginie Marécal, Yasmine Bennouna, Romain Blot, Damien Boulanger, Hannah Clark, Jean-Marc Cousin, Philippe Nedelec, and Valérie Thouret
Atmos. Chem. Phys., 24, 13975–14004, https://doi.org/10.5194/acp-24-13975-2024, https://doi.org/10.5194/acp-24-13975-2024, 2024
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Our study examines intense-carbon-monoxide (CO) pollution events measured by commercial aircraft from the In-service Aircraft for a Global Observing System (IAGOS) research infrastructure. We combine these measurements with the SOFT-IO model to trace the origin of the observed CO. A comprehensive analysis of the geographical origin, source type, seasonal variation, and ozone levels of these pollution events is provided.
This article is included in the Encyclopedia of Geosciences
Hassnae Erraji, Philipp Franke, Astrid Lampert, Tobias Schuldt, Ralf Tillmann, Andreas Wahner, and Anne Caroline Lange
Atmos. Chem. Phys., 24, 13913–13934, https://doi.org/10.5194/acp-24-13913-2024, https://doi.org/10.5194/acp-24-13913-2024, 2024
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Four-dimensional variational data assimilation allows for the simultaneous optimisation of initial values and emission rates by using trace-gas profiles from drone observations in a regional air quality model. Assimilated profiles positively impact the representation of air pollutants in the model by improving their vertical distribution and ground-level concentrations. This case study highlights the potential of drone data to enhance air quality analyses including local emission evaluation.
This article is included in the Encyclopedia of Geosciences
Christopher Lawrence, Mary Barth, John Orlando, Paul Casson, Richard Brandt, Daniel Kelting, Elizabeth Yerger, and Sara Lance
Atmos. Chem. Phys., 24, 13693–13713, https://doi.org/10.5194/acp-24-13693-2024, https://doi.org/10.5194/acp-24-13693-2024, 2024
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This work uses chemical transport and box modeling to study the gas- and aqueous-phase production of organic acid concentrations measured in cloud water at the summit of Whiteface Mountain on 1 July 2018. Isoprene was the major source of formic, acetic, and oxalic acid. Gas-phase chemistry greatly underestimated formic and acetic acid, indicating missing sources, while cloud chemistry was a key source of oxalic acid. More studies of organic acids are required to better constrain their sources.
This article is included in the Encyclopedia of Geosciences
Markus Kilian, Volker Grewe, Patrick Jöckel, Astrid Kerkweg, Mariano Mertens, Andreas Zahn, and Helmut Ziereis
Atmos. Chem. Phys., 24, 13503–13523, https://doi.org/10.5194/acp-24-13503-2024, https://doi.org/10.5194/acp-24-13503-2024, 2024
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Anthropogenic emissions are a major source of precursors of tropospheric ozone. As ozone formation is highly non-linear, we apply a global–regional chemistry–climate model with a source attribution method (tagging) to quantify the contribution of anthropogenic emissions to ozone. Our analysis shows that the contribution of European anthropogenic emissions largely increases during large ozone periods, indicating that emissions from these sectors drive ozone values.
This article is included in the Encyclopedia of Geosciences
Jianing Dai, Guy P. Brasseur, Mihalis Vrekoussis, Maria Kanakidou, Kun Qu, Yijuan Zhang, Hongliang Zhang, and Tao Wang
Atmos. Chem. Phys., 24, 12943–12962, https://doi.org/10.5194/acp-24-12943-2024, https://doi.org/10.5194/acp-24-12943-2024, 2024
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This paper employs a regional chemical transport model to quantify the sensitivity of air pollutants and photochemical parameters to specified emission reductions in China for representative winter and summer conditions. The study provides insights into further air quality control in China with reduced primary emissions.
This article is included in the Encyclopedia of Geosciences
T. Nash Skipper, Emma L. D'Ambro, Forwood C. Wiser, V. Faye McNeill, Rebecca H. Schwantes, Barron H. Henderson, Ivan R. Piletic, Colleen B. Baublitz, Jesse O. Bash, Andrew R. Whitehill, Lukas C. Valin, Asher P. Mouat, Jennifer Kaiser, Glenn M. Wolfe, Jason M. St. Clair, Thomas F. Hanisco, Alan Fried, Bryan K. Place, and Havala O.T. Pye
Atmos. Chem. Phys., 24, 12903–12924, https://doi.org/10.5194/acp-24-12903-2024, https://doi.org/10.5194/acp-24-12903-2024, 2024
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We develop the Community Regional Atmospheric Chemistry Multiphase Mechanism (CRACMM) version 2 to improve predictions of formaldehyde in ambient air compared to satellite-, aircraft-, and ground-based observations. With the updated chemistry, we estimate the cancer risk from inhalation exposure to ambient formaldehyde across the contiguous USA and predict that 40 % of this risk is controllable through reductions in anthropogenic emissions of nitrogen oxides and reactive organic carbon.
This article is included in the Encyclopedia of Geosciences
Baoshuang Liu, Yao Gu, Yutong Wu, Qili Dai, Shaojie Song, Yinchang Feng, and Philip K. Hopke
Atmos. Chem. Phys., 24, 12861–12879, https://doi.org/10.5194/acp-24-12861-2024, https://doi.org/10.5194/acp-24-12861-2024, 2024
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Reactive loss of volatile organic compounds (VOCs) is a long-term issue yet to be resolved in VOC source analyses. We assess common methods of, and existing issues in, reducing losses, impacts of losses, and sources in current source analyses. We offer a potential supporting role for solving issues of VOC conversion. Source analyses of consumed VOCs that reacted to produce ozone and secondary organic aerosols can play an important role in the effective control of secondary pollution in air.
This article is included in the Encyclopedia of Geosciences
Deepangsu Chatterjee, Randall V. Martin, Chi Li, Dandan Zhang, Haihui Zhu, Daven K. Henze, James H. Crawford, Ronald C. Cohen, Lok N. Lamsal, and Alexander M. Cede
Atmos. Chem. Phys., 24, 12687–12706, https://doi.org/10.5194/acp-24-12687-2024, https://doi.org/10.5194/acp-24-12687-2024, 2024
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We investigate the hourly variation of NO2 columns and surface concentrations by applying the GEOS-Chem model to interpret aircraft and ground-based measurements over the US and Pandora sun photometer measurements over the US, Europe, and Asia. Corrections to the Pandora columns and finer model resolution improve the modeled representation of the summertime hourly variation of total NO2 columns to explain the weaker hourly variation in NO2 columns than at the surface.
This article is included in the Encyclopedia of Geosciences
Kiyeon Kim, Kyung Man Han, Chul Han Song, Hyojun Lee, Ross Beardsley, Jinhyeok Yu, Greg Yarwood, Bonyoung Koo, Jasper Madalipay, Jung-Hun Woo, and Seogju Cho
Atmos. Chem. Phys., 24, 12575–12593, https://doi.org/10.5194/acp-24-12575-2024, https://doi.org/10.5194/acp-24-12575-2024, 2024
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We incorporated each HONO process into the current CMAQ modeling framework to enhance the accuracy of HONO mixing ratio predictions. These results expand our understanding of HONO photochemistry and identify crucial sources of HONO that impact the total HONO budget in Seoul, South Korea. Through this investigation, we contribute to resolving discrepancies in understanding chemical transport models, with implications for better air quality management and environmental protection in the region.
This article is included in the Encyclopedia of Geosciences
Flossie Brown, Gerd Folberth, Stephen Sitch, Paulo Artaxo, Marijn Bauters, Pascal Boeckx, Alexander W. Cheesman, Matteo Detto, Ninong Komala, Luciana Rizzo, Nestor Rojas, Ines dos Santos Vieira, Steven Turnock, Hans Verbeeck, and Alfonso Zambrano
Atmos. Chem. Phys., 24, 12537–12555, https://doi.org/10.5194/acp-24-12537-2024, https://doi.org/10.5194/acp-24-12537-2024, 2024
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Ozone is a pollutant that is detrimental to human and plant health. Ozone monitoring sites in the tropics are limited, so models are often used to understand ozone exposure. We use measurements from the tropics to evaluate ozone from the UK Earth system model, UKESM1. UKESM1 is able to capture the pattern of ozone in the tropics, except in southeast Asia, although it systematically overestimates it at all sites. This work highlights that UKESM1 can capture seasonal and hourly variability.
This article is included in the Encyclopedia of Geosciences
Namrata Shanmukh Panji, Deborah F. McGlynn, Laura E. R. Barry, Todd M. Scanlon, Manuel T. Lerdau, Sally E. Pusede, and Gabriel Isaacman-VanWertz
Atmos. Chem. Phys., 24, 12495–12507, https://doi.org/10.5194/acp-24-12495-2024, https://doi.org/10.5194/acp-24-12495-2024, 2024
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Climate change will bring about changes in parameters that are currently used in global-scale models to calculate biogenic emissions. This study seeks to understand the factors driving these models by comparing long-term datasets of biogenic compounds to modeled emissions. We note that the light-dependent fractions currently used in models do not accurately represent regional observations. We provide evidence for the time-dependent variation in this parameter for future modifications to models.
This article is included in the Encyclopedia of Geosciences
Martin Vojta, Andreas Plach, Saurabh Annadate, Sunyoung Park, Gawon Lee, Pallav Purohit, Florian Lindl, Xin Lan, Jens Mühle, Rona L. Thompson, and Andreas Stohl
Atmos. Chem. Phys., 24, 12465–12493, https://doi.org/10.5194/acp-24-12465-2024, https://doi.org/10.5194/acp-24-12465-2024, 2024
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We constrain the global emissions of the very potent greenhouse gas sulfur hexafluoride (SF6) between 2005 and 2021. We show that SF6 emissions are decreasing in the USA and in the EU, while they are substantially growing in China, leading overall to an increasing global emission trend. The national reports for the USA, EU, and China all underestimated their SF6 emissions. However, stringent mitigation measures can successfully reduce SF6 emissions, as can be seen in the EU emission trend.
This article is included in the Encyclopedia of Geosciences
Yasin Elshorbany, Jerald R. Ziemke, Sarah Strode, Hervé Petetin, Kazuyuki Miyazaki, Isabelle De Smedt, Kenneth Pickering, Rodrigo J. Seguel, Helen Worden, Tamara Emmerichs, Domenico Taraborrelli, Maria Cazorla, Suvarna Fadnavis, Rebecca R. Buchholz, Benjamin Gaubert, Néstor Y. Rojas, Thiago Nogueira, Thérèse Salameh, and Min Huang
Atmos. Chem. Phys., 24, 12225–12257, https://doi.org/10.5194/acp-24-12225-2024, https://doi.org/10.5194/acp-24-12225-2024, 2024
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We investigated tropospheric ozone spatial variability and trends from 2005 to 2019 and related those to ozone precursors on global and regional scales. We also investigate the spatiotemporal characteristics of the ozone formation regime in relation to ozone chemical sources and sinks. Our analysis is based on remote sensing products of the tropospheric column of ozone and its precursors, nitrogen dioxide, formaldehyde, and total column CO, as well as ozonesonde data and model simulations.
This article is included in the Encyclopedia of Geosciences
Mariano Mertens, Sabine Brinkop, Phoebe Graf, Volker Grewe, Johannes Hendricks, Patrick Jöckel, Anna Lanteri, Sigrun Matthes, Vanessa S. Rieger, Mattia Righi, and Robin N. Thor
Atmos. Chem. Phys., 24, 12079–12106, https://doi.org/10.5194/acp-24-12079-2024, https://doi.org/10.5194/acp-24-12079-2024, 2024
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We quantified the contributions of land transport, shipping, and aviation emissions to tropospheric ozone; its radiative forcing; and the reductions of the methane lifetime using chemistry-climate model simulations. The contributions were analysed for the conditions of 2015 and for three projections for the year 2050. The results highlight the challenges of mitigating ozone formed by emissions of the transport sector, caused by the non-linearitiy of the ozone chemistry and the long lifetime.
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Lauri Franzon, Marie Camredon, Richard Valorso, Bernard Aumont, and Theo Kurtén
Atmos. Chem. Phys., 24, 11679–11699, https://doi.org/10.5194/acp-24-11679-2024, https://doi.org/10.5194/acp-24-11679-2024, 2024
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In this article we investigate the formation of large, sticky molecules from various organic compounds entering the atmosphere as primary emissions and the degree to which these processes may contribute to organic aerosol particle mass. More specifically, we qualitatively investigate a recently discovered chemical reaction channel for one of the most important short-lived radical compounds, peroxy radicals, and discover which of these reactions are most atmospherically important.
This article is included in the Encyclopedia of Geosciences
Siting Li, Yiming Liu, Yuqi Zhu, Yinbao Jin, Yingying Hong, Ao Shen, Yifei Xu, Haofan Wang, Haichao Wang, Xiao Lu, Shaojia Fan, and Qi Fan
Atmos. Chem. Phys., 24, 11521–11544, https://doi.org/10.5194/acp-24-11521-2024, https://doi.org/10.5194/acp-24-11521-2024, 2024
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This study establishes an inventory of anthropogenic chlorine emissions in China in 2019 with expanded species (HCl, Cl-, Cl2, HOCl) and sources (41 specific sources). The inventory is validated by a modeling study against the observations. This study enhances the understanding of anthropogenic chlorine emissions in the atmosphere, identifies key sources, and provides scientific support for pollution control and climate change.
This article is included in the Encyclopedia of Geosciences
Willem E. van Caspel, Zbigniew Klimont, Chris Heyes, and Hilde Fagerli
Atmos. Chem. Phys., 24, 11545–11563, https://doi.org/10.5194/acp-24-11545-2024, https://doi.org/10.5194/acp-24-11545-2024, 2024
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Methane in the atmosphere contributes to the production of ozone gas – an air pollutant and greenhouse gas. Our results highlight that simultaneous reductions in methane emissions help avoid offsetting the air pollution benefits already achieved by the already-approved precursor emission reductions by 2050 in the European Monitoring and Evaluation Programme region, while also playing an important role in bringing air pollution further down towards World Health Organization guideline limits.
This article is included in the Encyclopedia of Geosciences
Jinya Yang, Yutong Wang, Lei Zhang, and Yu Zhao
EGUsphere, https://doi.org/10.5194/egusphere-2024-2713, https://doi.org/10.5194/egusphere-2024-2713, 2024
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We develop a modeling framework to predict future ozone concentrations (till 2060s) in China following an IPCC scenario. We further evaluate and separate the contributions of climatic, anthropogenic, and biogenic factors by season and region. We find persistent emission controls will alter the nonlinear response of ozone to its precursors, and dominate the declining ozone level. The outcomes highlight the importance of human actions even with a climate penalty on air quality in the future.
This article is included in the Encyclopedia of Geosciences
Laura Stecher, Franziska Winterstein, Patrick Jöckel, Michael Ponater, Mariano Mertens, and Martin Dameris
EGUsphere, https://doi.org/10.5194/egusphere-2024-2938, https://doi.org/10.5194/egusphere-2024-2938, 2024
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Methane, the second most important anthropogenic greenhouse gas, is chemically decomposed in the atmosphere. The chemical sink of atmospheric methane is not constant, but depends on the temperature and on the abundance of its reaction partners. In this study, we use a global chemistry-climate model to assess the feedback of atmospheric methane induced by changes of the chemical sink in a warming climate, and its implications for the chemical composition and the surface air temperature change.
This article is included in the Encyclopedia of Geosciences
Beata Opacka, Trissevgeni Stavrakou, Jean-François Müller, Isabelle De Smedt, Jos van Geffen, Eloise A. Marais, Rebekah P. Horner, Dylan B. Millet, Kelly C. Wells, and Alex B. Guenther
EGUsphere, https://doi.org/10.5194/egusphere-2024-2912, https://doi.org/10.5194/egusphere-2024-2912, 2024
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Vegetation releases biogenic volatile organic compounds, while soils and lightning contribute to the natural emissions of nitrogen oxides into the atmosphere. These gases interact in complex ways. Using satellite data and models, we developed a new method to simultaneously optimise these natural emissions over Africa in 2019. Our approach led to an increase in natural emissions that is supported by independent data showing that current estimates are underestimated.
This article is included in the Encyclopedia of Geosciences
Tia R. Scarpelli, Paul I. Palmer, Mark Lunt, Ingrid Super, and Arjan Droste
Atmos. Chem. Phys., 24, 10773–10791, https://doi.org/10.5194/acp-24-10773-2024, https://doi.org/10.5194/acp-24-10773-2024, 2024
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Under the Paris Agreement, countries must track their anthropogenic greenhouse gas emissions. This study describes a method to determine self-consistent estimates for combustion emissions and natural fluxes of CO2 from atmospheric data. We report consistent estimates inferred using this approach from satellite data and ground-based data over Europe, suggesting that satellite data can be used to determine national anthropogenic CO2 emissions for countries where ground-based CO2 data are absent.
This article is included in the Encyclopedia of Geosciences
Yufen Wang, Ke Li, Xi Chen, Zhenjiang Yang, Minglong Tang, Pascoal M. D. Campos, Yang Yang, Xu Yue, and Hong Liao
EGUsphere, https://doi.org/10.5194/egusphere-2024-2576, https://doi.org/10.5194/egusphere-2024-2576, 2024
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The impact of biomass burning and anthropogenic emissions on high tropospheric ozone was not well studied in Southern Africa. We combined the model simulation with recent observations at the surface and from space to quantify tropospheric ozone and its main drivers in Southern Africa. Our work focuses on the impact of emissions from different sources at different spatial scales, contributing to a comprehensive understanding of air pollution drivers and their uncertainties in Southern Africa.
This article is included in the Encyclopedia of Geosciences
Wenbin Kou, Yang Gao, Dan Tong, Xiaojie Guo, Xiadong An, Wenyu Liu, Mengshi Cui, Xiuwen Guo, Shaoqing Zhang, Huiwang Gao, and Lixin Wu
EGUsphere, https://doi.org/10.5194/egusphere-2024-2500, https://doi.org/10.5194/egusphere-2024-2500, 2024
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Unlike traditional numerical studies, we apply a high-resolution Earth system model, improving simulations of ozone and large-scale circulations such as atmospheric blocking. In addition to local heatwave effects, we quantify the impact of atmospheric blocking on downstream ozone concentrations, which is closely associated with the blocking position. We identify three major pathways of Rossby wave propagation, stressing the critical role of large-scale circulation play in regional air quality.
This article is included in the Encyclopedia of Geosciences
Qianqian Zhang, K. Folkert Boersma, Chiel van der Laan, Alba Mols, Bin Zhao, Shengyue Li, and Yuepeng Pan
EGUsphere, https://doi.org/10.5194/egusphere-2024-2641, https://doi.org/10.5194/egusphere-2024-2641, 2024
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Accurate NOx emission estimates are required to better understand air pollution. This study investigates and demonstrates the ability of the superposition column model in combination with TROPOMI tropospheric NO2 column data to estimate city-scale NOx emissions and lifetimes and their variabilities. The results of this work nevertheless confirm the strength of the superposition column model in estimating urban NOx emissions with reasonable accuracy.
This article is included in the Encyclopedia of Geosciences
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.
This article is included in the Encyclopedia of Geosciences
Mingzhao Liu, Lars Hoffmann, Jens-Uwe Grooß, Zhongyin Cai, Sabine Grießbach, and Yi Heng
EGUsphere, https://doi.org/10.5194/egusphere-2024-2596, https://doi.org/10.5194/egusphere-2024-2596, 2024
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We studied the transport and chemical decomposition of volcanic SO2, focusing on the 2019 Raikoke event. By comparing two different chemistry modeling schemes, we found that including complex chemical reactions leads to a more accurate prediction of how long SO2 stays in the atmosphere. This research helps improve our understanding of volcanic pollution and its impact on air quality and climate, providing better tools for scientists to track and predict the movement of these pollutants.
This article is included in the Encyclopedia of Geosciences
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.
This article is included in the Encyclopedia of Geosciences
Beth S. Nelson, Zhenze Liu, Freya A. Squires, Marvin Shaw, James R. Hopkins, Jacqueline F. Hamilton, Andrew R. Rickard, Alastair C. Lewis, Zongbo Shi, and James D. Lee
Atmos. Chem. Phys., 24, 9031–9044, https://doi.org/10.5194/acp-24-9031-2024, https://doi.org/10.5194/acp-24-9031-2024, 2024
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The impact of combined air quality and carbon neutrality policies on O3 formation in Beijing was investigated. Emissions inventory data were used to estimate future pollutant mixing ratios relative to ground-level observations. O3 production was found to be most sensitive to changes in alkenes, but large reductions in less reactive compounds led to larger reductions in future O3 production. This study highlights the importance of understanding the emissions of organic pollutants.
This article is included in the Encyclopedia of Geosciences
Takashi Sekiya, Emanuele Emili, Kazuyuki Miyazaki, Antje Inness, Zhen Qu, R. Bradley Pierce, Dylan Jones, Helen Worden, William Y. Y. Cheng, Vincent Huijnen, and Gerbrand Koren
EGUsphere, https://doi.org/10.5194/egusphere-2024-2426, https://doi.org/10.5194/egusphere-2024-2426, 2024
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Five global chemical reanalysis datasets were used to assess the relative impacts of assimilating satellite ozone and its precursors measurements on tropospheric ozone analyses for 2010. The multiple reanalysis system comparison allows for evaluating dependency of the impacts on different reanalysis systems. The results suggested the importance of satellite ozone and its precursor measurements for improving ozone analysis in the whole troposphere, with varying the magnitudes among the systems.
This article is included in the Encyclopedia of Geosciences
Maureen Beaudor, Didier Hauglustaine, Juliette Lathière, Martin Van Damme, Lieven Clarisse, and Nicolas Vuichard
EGUsphere, https://doi.org/10.5194/egusphere-2024-2022, https://doi.org/10.5194/egusphere-2024-2022, 2024
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Agriculture is the biggest ammonia (NH3) source, impacting air quality, climate, and ecosystems. Because of food demand, NH3 emissions are projected to rise by 2100. Using a global model, we analyzed the impact of present and future NH3 emissions generated from a land model. Our results show improved ammonia patterns compared to a reference inventory. Future scenarios predict up to 70 % increase in global NH3 burden, significant changes in radiative forcing, and could significantly elevate N2O.
This article is included in the Encyclopedia of Geosciences
Amir H. Souri, Bryan N. Duncan, Sarah A. Strode, Daniel C. Anderson, Michael E. Manyin, Junhua Liu, Luke D. Oman, Zhen Zhang, and Brad Weir
Atmos. Chem. Phys., 24, 8677–8701, https://doi.org/10.5194/acp-24-8677-2024, https://doi.org/10.5194/acp-24-8677-2024, 2024
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We explore a new method of using the wealth of information obtained from satellite observations of Aura OMI NO2, HCHO, and MERRA-2 reanalysis in NASA’s GEOS model equipped with an efficient tropospheric OH (TOH) estimator to enhance the representation of TOH spatial distribution and its long-term trends. This new framework helps us pinpoint regional inaccuracies in TOH and differentiate between established prior knowledge and newly acquired information from satellites on TOH trends.
This article is included in the Encyclopedia of Geosciences
Haipeng Lin, Louisa K. Emmons, Elizabeth W. Lundgren, Laura Hyesung Yang, Xu Feng, Ruijun Dang, Shixian Zhai, Yunxiao Tang, Makoto M. Kelp, Nadia K. Colombi, Sebastian D. Eastham, Thibaud M. Fritz, and Daniel J. Jacob
Atmos. Chem. Phys., 24, 8607–8624, https://doi.org/10.5194/acp-24-8607-2024, https://doi.org/10.5194/acp-24-8607-2024, 2024
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Tropospheric ozone is a major air pollutant, a greenhouse gas, and a major indicator of model skill. Global atmospheric chemistry models show large differences in simulations of tropospheric ozone, but isolating sources of differences is complicated by different model environments. By implementing the GEOS-Chem model side by side to CAM-chem within a common Earth system model, we identify and evaluate specific differences between the two models and their impacts on key chemical species.
This article is included in the Encyclopedia of Geosciences
Victor Lannuque and Karine Sartelet
Atmos. Chem. Phys., 24, 8589–8606, https://doi.org/10.5194/acp-24-8589-2024, https://doi.org/10.5194/acp-24-8589-2024, 2024
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Large uncertainties remain in understanding secondary organic aerosol (SOA) formation and speciation from naphthalene oxidation. This study details the development of the first near-explicit chemical scheme for naphthalene oxidation by OH, which includes kinetic and mechanistic data, and is able to reproduce most of the experimentally identified products in both gas and particle phases.
This article is included in the Encyclopedia of Geosciences
Hui Li, Jiaxin Qiu, and Bo Zheng
EGUsphere, https://doi.org/10.5194/egusphere-2024-1986, https://doi.org/10.5194/egusphere-2024-1986, 2024
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We conduct a sensitivity analysis on various factors including prior, model resolution, satellite constraint, and inversion system configuration to assess the vulnerability of emission estimates across temporal, sectoral, and regional dimensions. Our analysis first reveals the robustness of emissions estimated by this air pollution satellite sensor-based CO2 emission inversion system, with relative change between tests and Base inversion below 4.0 % for national annual NOx and CO2 emissions.
This article is included in the Encyclopedia of Geosciences
Shuai Li, Xiao Lu, and Haolin Wang
EGUsphere, https://doi.org/10.5194/egusphere-2024-1889, https://doi.org/10.5194/egusphere-2024-1889, 2024
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We report that the summertime ozone-temperature sensitivity decreased by 50 % from 3.0 ppbv/K in 1990 to 1.5 ppb/K in 2021 in the US. GEOS-Chem simulations show that anthropogenic NOx emission reduction is the dominant driver of the ozone-temperature sensitivity decline, through influencing both the temperature-direct and temperature-indirect processes. Reduced ozone-temperature sensitivity has decreased the ozone enhancement from low to high temperatures by an average of 6.8 ppbv across the US.
This article is included in the Encyclopedia of Geosciences
Tong Sha, Siyu Yang, Qingcai Chen, Liangqing Li, Xiaoyan Ma, Yan-Lin Zhang, Zhaozhong Feng, K. Folkert Boersma, and Jun Wang
Atmos. Chem. Phys., 24, 8441–8455, https://doi.org/10.5194/acp-24-8441-2024, https://doi.org/10.5194/acp-24-8441-2024, 2024
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Using an updated soil reactive nitrogen emission scheme in the Unified Inputs for Weather Research and Forecasting coupled with Chemistry (UI-WRF-Chem) model, we investigate the role of soil NO and HONO (Nr) emissions in air quality and temperature in North China. Contributions of soil Nr emissions to O3 and secondary pollutants are revealed, exceeding effects of soil NOx or HONO emission. Soil Nr emissions play an important role in mitigating O3 pollution and addressing climate change.
This article is included in the Encyclopedia of Geosciences
Jian Zhu, Shanshan Wang, Chuanqi Gu, Zhiwen Jiang, Sanbao Zhang, Ruibin Xue, Yuhao Yan, and Bin Zhou
Atmos. Chem. Phys., 24, 8383–8395, https://doi.org/10.5194/acp-24-8383-2024, https://doi.org/10.5194/acp-24-8383-2024, 2024
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In 2022, Shanghai implemented city-wide static management measures during the high-ozone season in April and May, providing a chance to study ozone pollution control. Despite significant emissions reductions, ozone levels increased by 23 %. Statistically, the number of days with higher ozone diurnal variation types increased during the lockdown period. The uneven decline in VOC and NO2 emissions led to heightened photochemical processes, resulting in the observed ozone level rise.
This article is included in the Encyclopedia of Geosciences
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.
This article is included in the Encyclopedia of Geosciences
Rodrigo J. Seguel, Lucas Castillo, Charlie Opazo, Néstor Y. Rojas, Thiago Nogueira, María Cazorla, Mario Gavidia-Calderón, Laura Gallardo, René Garreaud, Tomás Carrasco-Escaff, and Yasin Elshorbany
Atmos. Chem. Phys., 24, 8225–8242, https://doi.org/10.5194/acp-24-8225-2024, https://doi.org/10.5194/acp-24-8225-2024, 2024
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Trends of surface ozone were examined across South America. Our findings indicate that ozone trends in major South American cities either increase or remain steady, with no signs of decline. The upward trends can be attributed to chemical regimes that efficiently convert nitric oxide into nitrogen dioxide. Additionally, our results suggest a climate penalty for ozone driven by meteorological conditions that favor wildfire propagation in Chile and extensive heat waves in southern Brazil.
This article is included in the Encyclopedia of Geosciences
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