Articles | Volume 23, issue 8
https://doi.org/10.5194/acp-23-4955-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-23-4955-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
28 Apr 2023
Research article |
| 28 Apr 2023
| 28 Apr 2023
Exploring the drivers of tropospheric hydroxyl radical trends in the Geophysical Fluid Dynamics Laboratory AM4.1 atmospheric chemistry–climate model
Program in Atmospheric and Oceanic Science, Princeton University, Princeton, NJ, USA
NOAA Geophysical Fluid Dynamics Laboratory, Princeton, NJ, USA
Vaishali Naik
NOAA Geophysical Fluid Dynamics Laboratory, Princeton, NJ, USA
Larry Wayne Horowitz
NOAA Geophysical Fluid Dynamics Laboratory, Princeton, NJ, USA
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Piers M. Forster, Chris Smith, Tristram Walsh, William F. Lamb, Robin Lamboll, Christophe Cassou, Mathias Hauser, Zeke Hausfather, June-Yi Lee, Matthew D. Palmer, Karina von Schuckmann, Aimée B. A. Slangen, Sophie Szopa, Blair Trewin, Jeongeun Yun, Nathan P. Gillett, Stuart Jenkins, H. Damon Matthews, Krishnan Raghavan, Aurélien Ribes, Joeri Rogelj, Debbie Rosen, Xuebin Zhang, Myles Allen, Lara Aleluia Reis, Robbie M. Andrew, Richard A. Betts, Alex Borger, Jiddu A. Broersma, Samantha N. Burgess, Lijing Cheng, Pierre Friedlingstein, Catia M. Domingues, Marco Gambarini, Thomas Gasser, Johannes Gütschow, Masayoshi Ishii, Christopher Kadow, John Kennedy, Rachel E. Killick, Paul B. Krummel, Aurélien Liné, Didier P. Monselesan, Colin Morice, Jens Mühle, Vaishali Naik, Glen P. Peters, Anna Pirani, Julia Pongratz, Jan C. Minx, Matthew Rigby, Robert Rohde, Abhishek Savita, Sonia I. Seneviratne, Peter Thorne, Christopher Wells, Luke M. Western, Guido R. van der Werf, Susan E. Wijffels, Valérie Masson-Delmotte, and Panmao Zhai
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-250, https://doi.org/10.5194/essd-2025-250, 2025
Preprint under review for ESSD
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In a rapidly changing climate, evidence-based decision-making benefits from up-to-date and timely information. Here we compile monitoring datasets to track real-world changes over time. To make our work relevant to policy makers, we follow methods from the Intergovernmental Panel on Climate Change (IPCC). Human activities are increasing the Earth's energy imbalance and driving faster sea-level rise compared to the IPCC assessment.
Ngoc Thi Nhu Do, Kengo Sudo, Akihiko Ito, Louisa K. Emmons, Vaishali Naik, Kostas Tsigaridis, Øyvind Seland, Gerd A. Folberth, and Douglas I. Kelley
Geosci. Model Dev., 18, 2079–2109, https://doi.org/10.5194/gmd-18-2079-2025, https://doi.org/10.5194/gmd-18-2079-2025, 2025
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Understanding historical isoprene emission changes is important for predicting future climate, but trends and their controlling factors remain uncertain. This study shows that long-term isoprene trends vary among Earth system models mainly due to partially incorporating CO2 effects and land cover changes rather than to climate. Future models that refine these factors’ effects on isoprene emissions, along with long-term observations, are essential for better understanding plant–climate interactions.
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.
John Patrick Dunne, Helene T. Hewitt, Julie Arblaster, Frédéric Bonou, Olivier Boucher, Tereza Cavazos, Paul J. Durack, Birgit Hassler, Martin Juckes, Tomoki Miyakawa, Matthew Mizielinski, Vaishali Naik, Zebedee Nicholls, Eleanor O’Rourke, Robert Pincus, Benjamin M. Sanderson, Isla R. Simpson, and Karl E. Taylor
EGUsphere, https://doi.org/10.5194/egusphere-2024-3874, https://doi.org/10.5194/egusphere-2024-3874, 2024
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This manuscript provides the motivation and experimental design for the seventh phase of the Coupled Model Intercomparison Project (CMIP7) to coordinate community based efforts to answer key and timely climate science questions and facilitate delivery of relevant multi-model simulations for: prediction and projection, characterization, attribution and process understanding; vulnerability, impacts and adaptations analysis; national and international climate assessments; and society at large.
William J. Collins, Fiona M. O'Connor, Connor R. Barker, Rachael E. Byrom, Sebastian D. Eastham, Øivind Hodnebrog, Patrick Jöckel, Eloise A. Marais, Mariano Mertens, Gunnar Myhre, Matthias Nützel, Dirk Olivié, Ragnhild Bieltvedt Skeie, Laura Stecher, Larry W. Horowitz, Vaishali Naik, Gregory Faluvegi, Ulas Im, Lee T. Murray, Drew Shindell, Kostas Tsigaridis, Nathan Luke Abraham, and James Keeble
EGUsphere, https://doi.org/10.5194/egusphere-2024-3698, https://doi.org/10.5194/egusphere-2024-3698, 2024
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If reductions aren’t implemented to limit emissions of pollutants that produce ozone then we calculate that this will cause a warming of climate. We assess how the future warming from ozone is affected by changing meteorological variables such as clouds and atmospheric temperatures. We find that reductions in high cloud cover tend to slightly reduce the warming from ozone.
Steven Turnock, Dimitris Akritidis, Larry Horowitz, Mariano Mertens, Andrea Pozzer, Carly Reddington, Hantao Wang, Putian Zhou, and Fiona O'Connor
EGUsphere, https://doi.org/10.5194/egusphere-2024-2732, https://doi.org/10.5194/egusphere-2024-2732, 2024
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We assess the drivers behind changes in peak season surface zone concentrations and risk to human health between 1850 and 2014. Substantial increases in surface ozone have occurred over this period resulting in a significant increase in the risk to human health, mainly driven by increases in anthropogenic NOx emissions and global CH4 concentrations. Fixing anthropogenic NOx emissions at 1850 values in the near present-day period can eliminate the risk to human health.
Paul T. Griffiths, Laura J. Wilcox, Robert J. Allen, Vaishali Naik, Fiona M. O'Connor, Michael J. Prather, Alexander T. Archibald, Florence Brown, Makoto Deushi, William Collins, Stephanie Fiedler, Naga Oshima, Lee T. Murray, Christopher J. Smith, Steven T. Turnock, Duncan Watson-Parris, and Paul J. Young
EGUsphere, https://doi.org/10.5194/egusphere-2024-2528, https://doi.org/10.5194/egusphere-2024-2528, 2024
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The Aerosol Chemistry Model Intercomparison Project (AerChemMIP) aimed to quantify the climate and air quality impacts of aerosols and chemically reactive gases. In this paper, we review its contribution to AR6, and the wider understanding of the role of these species in climate and climate change. We identify remaining challenges concluding with recommendations aimed to improve the utility and uptake of climate model data to address the role of short-lived climate forcers in the Earth system.
Alkiviadis Kalisoras, Aristeidis K. Georgoulias, Dimitris Akritidis, Robert J. Allen, Vaishali Naik, Chaincy Kuo, Sophie Szopa, Pierre Nabat, Dirk Olivié, Twan van Noije, Philippe Le Sager, David Neubauer, Naga Oshima, Jane Mulcahy, Larry W. Horowitz, and Prodromos Zanis
Atmos. Chem. Phys., 24, 7837–7872, https://doi.org/10.5194/acp-24-7837-2024, https://doi.org/10.5194/acp-24-7837-2024, 2024
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Effective radiative forcing (ERF) is a metric for estimating how human activities and natural agents change the energy flow into and out of the Earth’s climate system. We investigate the anthropogenic aerosol ERF, and we estimate the contribution of individual processes to the total ERF using simulations from Earth system models within the Coupled Model Intercomparison Project Phase 6 (CMIP6). Our findings highlight that aerosol–cloud interactions drive ERF variability during the last 150 years.
Fangxuan Ren, Jintai Lin, Chenghao Xu, Jamiu A. Adeniran, Jingxu Wang, Randall V. Martin, Aaron van Donkelaar, Melanie S. Hammer, Larry W. Horowitz, Steven T. Turnock, Naga Oshima, Jie Zhang, Susanne Bauer, Kostas Tsigaridis, Øyvind Seland, Pierre Nabat, David Neubauer, Gary Strand, Twan van Noije, Philippe Le Sager, and Toshihiko Takemura
Geosci. Model Dev., 17, 4821–4836, https://doi.org/10.5194/gmd-17-4821-2024, https://doi.org/10.5194/gmd-17-4821-2024, 2024
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We evaluate the performance of 14 CMIP6 ESMs in simulating total PM2.5 and its 5 components over China during 2000–2014. PM2.5 and its components are underestimated in almost all models, except that black carbon (BC) and sulfate are overestimated in two models, respectively. The underestimation is the largest for organic carbon (OC) and the smallest for BC. Models reproduce the observed spatial pattern for OC, sulfate, nitrate and ammonium well, yet the agreement is poorer for BC.
Piers M. Forster, Chris Smith, Tristram Walsh, William F. Lamb, Robin Lamboll, Bradley Hall, Mathias Hauser, Aurélien Ribes, Debbie Rosen, Nathan P. Gillett, Matthew D. Palmer, Joeri Rogelj, Karina von Schuckmann, Blair Trewin, Myles Allen, Robbie Andrew, Richard A. Betts, Alex Borger, Tim Boyer, Jiddu A. Broersma, Carlo Buontempo, Samantha Burgess, Chiara Cagnazzo, Lijing Cheng, Pierre Friedlingstein, Andrew Gettelman, Johannes Gütschow, Masayoshi Ishii, Stuart Jenkins, Xin Lan, Colin Morice, Jens Mühle, Christopher Kadow, John Kennedy, Rachel E. Killick, Paul B. Krummel, Jan C. Minx, Gunnar Myhre, Vaishali Naik, Glen P. Peters, Anna Pirani, Julia Pongratz, Carl-Friedrich Schleussner, Sonia I. Seneviratne, Sophie Szopa, Peter Thorne, Mahesh V. M. Kovilakam, Elisa Majamäki, Jukka-Pekka Jalkanen, Margreet van Marle, Rachel M. Hoesly, Robert Rohde, Dominik Schumacher, Guido van der Werf, Russell Vose, Kirsten Zickfeld, Xuebin Zhang, Valérie Masson-Delmotte, and Panmao Zhai
Earth Syst. Sci. Data, 16, 2625–2658, https://doi.org/10.5194/essd-16-2625-2024, https://doi.org/10.5194/essd-16-2625-2024, 2024
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This paper tracks some key indicators of global warming through time, from 1850 through to the end of 2023. It is designed to give an authoritative estimate of global warming to date and its causes. We find that in 2023, global warming reached 1.3 °C and is increasing at over 0.2 °C per decade. This is caused by all-time-high greenhouse gas emissions.
Stephanie Fiedler, Vaishali Naik, Fiona M. O'Connor, Christopher J. Smith, Paul Griffiths, Ryan J. Kramer, Toshihiko Takemura, Robert J. Allen, Ulas Im, Matthew Kasoar, Angshuman Modak, Steven Turnock, Apostolos Voulgarakis, Duncan Watson-Parris, Daniel M. Westervelt, Laura J. Wilcox, Alcide Zhao, William J. Collins, Michael Schulz, Gunnar Myhre, and Piers M. Forster
Geosci. Model Dev., 17, 2387–2417, https://doi.org/10.5194/gmd-17-2387-2024, https://doi.org/10.5194/gmd-17-2387-2024, 2024
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Climate scientists want to better understand modern climate change. Thus, climate model experiments are performed and compared. The results of climate model experiments differ, as assessed in the latest Intergovernmental Panel on Climate Change (IPCC) assessment report. This article gives insights into the challenges and outlines opportunities for further improving the understanding of climate change. It is based on views of a group of experts in atmospheric composition–climate interactions.
Hamza Ahsan, Hailong Wang, Jingbo Wu, Mingxuan Wu, Steven J. Smith, Susanne Bauer, Harrison Suchyta, Dirk Olivié, Gunnar Myhre, Hitoshi Matsui, Huisheng Bian, Jean-François Lamarque, Ken Carslaw, Larry Horowitz, Leighton Regayre, Mian Chin, Michael Schulz, Ragnhild Bieltvedt Skeie, Toshihiko Takemura, and Vaishali Naik
Atmos. Chem. Phys., 23, 14779–14799, https://doi.org/10.5194/acp-23-14779-2023, https://doi.org/10.5194/acp-23-14779-2023, 2023
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We examine the impact of the assumed effective height of SO2 injection, SO2 and BC emission seasonality, and the assumed fraction of SO2 emissions injected as SO4 on climate and chemistry model results. We find that the SO2 injection height has a large impact on surface SO2 concentrations and, in some models, radiative flux. These assumptions are a
hiddensource of inter-model variability and may be leading to bias in some climate model results.
Yiqi Zheng, Larry W. Horowitz, Raymond Menzel, David J. Paynter, Vaishali Naik, Jingyi Li, and Jingqiu Mao
Atmos. Chem. Phys., 23, 8993–9007, https://doi.org/10.5194/acp-23-8993-2023, https://doi.org/10.5194/acp-23-8993-2023, 2023
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Biogenic secondary organic aerosols (SOAs) account for a large fraction of fine aerosol at the global scale. Using long-term measurements and a climate model, we investigate anthropogenic impacts on biogenic SOA at both decadal and centennial timescales. Results show that despite reductions in biogenic precursor emissions, SOA has been strongly amplified by anthropogenic emissions since the preindustrial era and exerts a cooling radiative forcing.
Piers M. Forster, Christopher J. Smith, Tristram Walsh, William F. Lamb, Robin Lamboll, Mathias Hauser, Aurélien Ribes, Debbie Rosen, Nathan Gillett, Matthew D. Palmer, Joeri Rogelj, Karina von Schuckmann, Sonia I. Seneviratne, Blair Trewin, Xuebin Zhang, Myles Allen, Robbie Andrew, Arlene Birt, Alex Borger, Tim Boyer, Jiddu A. Broersma, Lijing Cheng, Frank Dentener, Pierre Friedlingstein, José M. Gutiérrez, Johannes Gütschow, Bradley Hall, Masayoshi Ishii, Stuart Jenkins, Xin Lan, June-Yi Lee, Colin Morice, Christopher Kadow, John Kennedy, Rachel Killick, Jan C. Minx, Vaishali Naik, Glen P. Peters, Anna Pirani, Julia Pongratz, Carl-Friedrich Schleussner, Sophie Szopa, Peter Thorne, Robert Rohde, Maisa Rojas Corradi, Dominik Schumacher, Russell Vose, Kirsten Zickfeld, Valérie Masson-Delmotte, and Panmao Zhai
Earth Syst. Sci. Data, 15, 2295–2327, https://doi.org/10.5194/essd-15-2295-2023, https://doi.org/10.5194/essd-15-2295-2023, 2023
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This is a critical decade for climate action, but there is no annual tracking of the level of human-induced warming. We build on the Intergovernmental Panel on Climate Change assessment reports that are authoritative but published infrequently to create a set of key global climate indicators that can be tracked through time. Our hope is that this becomes an important annual publication that policymakers, media, scientists and the public can refer to.
Johannes Quaas, Hailing Jia, Chris Smith, Anna Lea Albright, Wenche Aas, Nicolas Bellouin, Olivier Boucher, Marie Doutriaux-Boucher, Piers M. Forster, Daniel Grosvenor, Stuart Jenkins, Zbigniew Klimont, Norman G. Loeb, Xiaoyan Ma, Vaishali Naik, Fabien Paulot, Philip Stier, Martin Wild, Gunnar Myhre, and Michael Schulz
Atmos. Chem. Phys., 22, 12221–12239, https://doi.org/10.5194/acp-22-12221-2022, https://doi.org/10.5194/acp-22-12221-2022, 2022
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Pollution particles cool climate and offset part of the global warming. However, they are washed out by rain and thus their effect responds quickly to changes in emissions. We show multiple datasets to demonstrate that aerosol emissions and their concentrations declined in many regions influenced by human emissions, as did the effects on clouds. Consequently, the cooling impact on the Earth energy budget became smaller. This change in trend implies a relative warming.
Henry Bowman, Steven Turnock, Susanne E. Bauer, Kostas Tsigaridis, Makoto Deushi, Naga Oshima, Fiona M. O'Connor, Larry Horowitz, Tongwen Wu, Jie Zhang, Dagmar Kubistin, and David D. Parrish
Atmos. Chem. Phys., 22, 3507–3524, https://doi.org/10.5194/acp-22-3507-2022, https://doi.org/10.5194/acp-22-3507-2022, 2022
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A full understanding of ozone in the troposphere requires investigation of its temporal variability over all timescales. Model simulations show that the northern midlatitude ozone seasonal cycle shifted with industrial development (1850–2014), with an increasing magnitude and a later summer peak. That shift reached a maximum in the mid-1980s, followed by a reversal toward the preindustrial cycle. The few available observations, beginning in the 1970s, are consistent with the model simulations.
James Keeble, Birgit Hassler, Antara Banerjee, Ramiro Checa-Garcia, Gabriel Chiodo, Sean Davis, Veronika Eyring, Paul T. Griffiths, Olaf Morgenstern, Peer Nowack, Guang Zeng, Jiankai Zhang, Greg Bodeker, Susannah Burrows, Philip Cameron-Smith, David Cugnet, Christopher Danek, Makoto Deushi, Larry W. Horowitz, Anne Kubin, Lijuan Li, Gerrit Lohmann, Martine Michou, Michael J. Mills, Pierre Nabat, Dirk Olivié, Sungsu Park, Øyvind Seland, Jens Stoll, Karl-Hermann Wieners, and Tongwen Wu
Atmos. Chem. Phys., 21, 5015–5061, https://doi.org/10.5194/acp-21-5015-2021, https://doi.org/10.5194/acp-21-5015-2021, 2021
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Stratospheric ozone and water vapour are key components of the Earth system; changes to both have important impacts on global and regional climate. We evaluate changes to these species from 1850 to 2100 in the new generation of CMIP6 models. There is good agreement between the multi-model mean and observations, although there is substantial variation between the individual models. The future evolution of both ozone and water vapour is strongly dependent on the assumed future emissions scenario.
Paul T. Griffiths, Lee T. Murray, Guang Zeng, Youngsub Matthew Shin, N. Luke Abraham, Alexander T. Archibald, Makoto Deushi, Louisa K. Emmons, Ian E. Galbally, Birgit Hassler, Larry W. Horowitz, James Keeble, Jane Liu, Omid Moeini, Vaishali Naik, Fiona M. O'Connor, Naga Oshima, David Tarasick, Simone Tilmes, Steven T. Turnock, Oliver Wild, Paul J. Young, and Prodromos Zanis
Atmos. Chem. Phys., 21, 4187–4218, https://doi.org/10.5194/acp-21-4187-2021, https://doi.org/10.5194/acp-21-4187-2021, 2021
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We analyse the CMIP6 Historical and future simulations for tropospheric ozone, a species which is important for many aspects of atmospheric chemistry. We show that the current generation of models agrees well with observations, being particularly successful in capturing trends in surface ozone and its vertical distribution in the troposphere. We analyse the factors that control ozone and show that they evolve over the period of the CMIP6 experiments.
Gillian Thornhill, William Collins, Dirk Olivié, Ragnhild B. Skeie, Alex Archibald, Susanne Bauer, Ramiro Checa-Garcia, Stephanie Fiedler, Gerd Folberth, Ada Gjermundsen, Larry Horowitz, Jean-Francois Lamarque, Martine Michou, Jane Mulcahy, Pierre Nabat, Vaishali Naik, Fiona M. O'Connor, Fabien Paulot, Michael Schulz, Catherine E. Scott, Roland Séférian, Chris Smith, Toshihiko Takemura, Simone Tilmes, Kostas Tsigaridis, and James Weber
Atmos. Chem. Phys., 21, 1105–1126, https://doi.org/10.5194/acp-21-1105-2021, https://doi.org/10.5194/acp-21-1105-2021, 2021
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We find that increased temperatures affect aerosols and reactive gases by changing natural emissions and their rates of removal from the atmosphere. Changing the composition of these species in the atmosphere affects the radiative budget of the climate system and therefore amplifies or dampens the climate response of climate models of the Earth system. This study found that the largest effect is a dampening of climate change as warmer temperatures increase the emissions of cooling aerosols.
Gillian D. Thornhill, William J. Collins, Ryan J. Kramer, Dirk Olivié, Ragnhild B. Skeie, Fiona M. O'Connor, Nathan Luke Abraham, Ramiro Checa-Garcia, Susanne E. Bauer, Makoto Deushi, Louisa K. Emmons, Piers M. Forster, Larry W. Horowitz, Ben Johnson, James Keeble, Jean-Francois Lamarque, Martine Michou, Michael J. Mills, Jane P. Mulcahy, Gunnar Myhre, Pierre Nabat, Vaishali Naik, Naga Oshima, Michael Schulz, Christopher J. Smith, Toshihiko Takemura, Simone Tilmes, Tongwen Wu, Guang Zeng, and Jie Zhang
Atmos. Chem. Phys., 21, 853–874, https://doi.org/10.5194/acp-21-853-2021, https://doi.org/10.5194/acp-21-853-2021, 2021
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This paper is a study of how different constituents in the atmosphere, such as aerosols and gases like methane and ozone, affect the energy balance in the atmosphere. Different climate models were run using the same inputs to allow an easy comparison of the results and to understand where the models differ. We found the effect of aerosols is to reduce warming in the atmosphere, but this effect varies between models. Reactions between gases are also important in affecting climate.
Steven T. Turnock, Robert J. Allen, Martin Andrews, Susanne E. Bauer, Makoto Deushi, Louisa Emmons, Peter Good, Larry Horowitz, Jasmin G. John, Martine Michou, Pierre Nabat, Vaishali Naik, David Neubauer, Fiona M. O'Connor, Dirk Olivié, Naga Oshima, Michael Schulz, Alistair Sellar, Sungbo Shim, Toshihiko Takemura, Simone Tilmes, Kostas Tsigaridis, Tongwen Wu, and Jie Zhang
Atmos. Chem. Phys., 20, 14547–14579, https://doi.org/10.5194/acp-20-14547-2020, https://doi.org/10.5194/acp-20-14547-2020, 2020
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A first assessment is made of the historical and future changes in air pollutants from models participating in the 6th Coupled Model Intercomparison Project (CMIP6). Substantial benefits to future air quality can be achieved in future scenarios that implement measures to mitigate climate and involve reductions in air pollutant emissions, particularly methane. However, important differences are shown between models in the future regional projection of air pollutants under the same scenario.
David S. Stevenson, Alcide Zhao, Vaishali Naik, Fiona M. O'Connor, Simone Tilmes, Guang Zeng, Lee T. Murray, William J. Collins, Paul T. Griffiths, Sungbo Shim, Larry W. Horowitz, Lori T. Sentman, and Louisa Emmons
Atmos. Chem. Phys., 20, 12905–12920, https://doi.org/10.5194/acp-20-12905-2020, https://doi.org/10.5194/acp-20-12905-2020, 2020
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We present historical trends in atmospheric oxidizing capacity (OC) since 1850 from the latest generation of global climate models and compare these with estimates from measurements. OC controls levels of many key reactive gases, including methane (CH4). We find small model trends up to 1980, then increases of about 9 % up to 2014, disagreeing with (uncertain) measurement-based trends. Major drivers of OC trends are emissions of CH4, NOx, and CO; these will be important for future CH4 trends.
Li Zhang, Meiyun Lin, Andrew O. Langford, Larry W. Horowitz, Christoph J. Senff, Elizabeth Klovenski, Yuxuan Wang, Raul J. Alvarez II, Irina Petropavlovskikh, Patrick Cullis, Chance W. Sterling, Jeff Peischl, Thomas B. Ryerson, Steven S. Brown, Zachary C. J. Decker, Guillaume Kirgis, and Stephen Conley
Atmos. Chem. Phys., 20, 10379–10400, https://doi.org/10.5194/acp-20-10379-2020, https://doi.org/10.5194/acp-20-10379-2020, 2020
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Measuring and quantifying the sources of elevated springtime ozone in the southwestern US is challenging but relevant to the implications for control policy. Here we use intensive field measurements and two global models to study ozone sources in the region. We find that ozone from the stratosphere, wildfires, and Asia is an important source of high-ozone events in the region. Our analysis also helps understand the uncertainties in ozone simulations with individual models.
Robert J. Allen, Steven Turnock, Pierre Nabat, David Neubauer, Ulrike Lohmann, Dirk Olivié, Naga Oshima, Martine Michou, Tongwen Wu, Jie Zhang, Toshihiko Takemura, Michael Schulz, Kostas Tsigaridis, Susanne E. Bauer, Louisa Emmons, Larry Horowitz, Vaishali Naik, Twan van Noije, Tommi Bergman, Jean-Francois Lamarque, Prodromos Zanis, Ina Tegen, Daniel M. Westervelt, Philippe Le Sager, Peter Good, Sungbo Shim, Fiona O'Connor, Dimitris Akritidis, Aristeidis K. Georgoulias, Makoto Deushi, Lori T. Sentman, Jasmin G. John, Shinichiro Fujimori, and William J. Collins
Atmos. Chem. Phys., 20, 9641–9663, https://doi.org/10.5194/acp-20-9641-2020, https://doi.org/10.5194/acp-20-9641-2020, 2020
Marielle Saunois, Ann R. Stavert, Ben Poulter, Philippe Bousquet, Josep G. Canadell, Robert B. Jackson, Peter A. Raymond, Edward J. Dlugokencky, Sander Houweling, Prabir K. Patra, Philippe Ciais, Vivek K. Arora, David Bastviken, Peter Bergamaschi, Donald R. Blake, Gordon Brailsford, Lori Bruhwiler, Kimberly M. Carlson, Mark Carrol, Simona Castaldi, Naveen Chandra, Cyril Crevoisier, Patrick M. Crill, Kristofer Covey, Charles L. Curry, Giuseppe Etiope, Christian Frankenberg, Nicola Gedney, Michaela I. Hegglin, Lena Höglund-Isaksson, Gustaf Hugelius, Misa Ishizawa, Akihiko Ito, Greet Janssens-Maenhout, Katherine M. Jensen, Fortunat Joos, Thomas Kleinen, Paul B. Krummel, Ray L. Langenfelds, Goulven G. Laruelle, Licheng Liu, Toshinobu Machida, Shamil Maksyutov, Kyle C. McDonald, Joe McNorton, Paul A. Miller, Joe R. Melton, Isamu Morino, Jurek Müller, Fabiola Murguia-Flores, Vaishali Naik, Yosuke Niwa, Sergio Noce, Simon O'Doherty, Robert J. Parker, Changhui Peng, Shushi Peng, Glen P. Peters, Catherine Prigent, Ronald Prinn, Michel Ramonet, Pierre Regnier, William J. Riley, Judith A. Rosentreter, Arjo Segers, Isobel J. Simpson, Hao Shi, Steven J. Smith, L. Paul Steele, Brett F. Thornton, Hanqin Tian, Yasunori Tohjima, Francesco N. Tubiello, Aki Tsuruta, Nicolas Viovy, Apostolos Voulgarakis, Thomas S. Weber, Michiel van Weele, Guido R. van der Werf, Ray F. Weiss, Doug Worthy, Debra Wunch, Yi Yin, Yukio Yoshida, Wenxin Zhang, Zhen Zhang, Yuanhong Zhao, Bo Zheng, Qing Zhu, Qiuan Zhu, and Qianlai Zhuang
Earth Syst. Sci. Data, 12, 1561–1623, https://doi.org/10.5194/essd-12-1561-2020, https://doi.org/10.5194/essd-12-1561-2020, 2020
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Understanding and quantifying the global methane (CH4) budget is important for assessing realistic pathways to mitigate climate change. We have established a consortium of multidisciplinary scientists under the umbrella of the Global Carbon Project to synthesize and stimulate new research aimed at improving and regularly updating the global methane budget. This is the second version of the review dedicated to the decadal methane budget, integrating results of top-down and bottom-up estimates.
Daniel M. Westervelt, Nora R. Mascioli, Arlene M. Fiore, Andrew J. Conley, Jean-François Lamarque, Drew T. Shindell, Greg Faluvegi, Michael Previdi, Gustavo Correa, and Larry W. Horowitz
Atmos. Chem. Phys., 20, 3009–3027, https://doi.org/10.5194/acp-20-3009-2020, https://doi.org/10.5194/acp-20-3009-2020, 2020
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We use three Earth system models to estimate the impact of regional air pollutant emissions reductions on global and regional surface temperature. We find that removing human-caused air pollutant emissions from certain world regions (such as the USA) results in warming of up to 0.15 °C. We use our model output to calculate simple climate metrics that will allow for regional-scale climate impact estimates without the use of computationally demanding computer models.
Jian He, Vaishali Naik, Larry W. Horowitz, Ed Dlugokencky, and Kirk Thoning
Atmos. Chem. Phys., 20, 805–827, https://doi.org/10.5194/acp-20-805-2020, https://doi.org/10.5194/acp-20-805-2020, 2020
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In this work, methane representation in AM4.1 is improved by optimizing CH4 emissions to match surface observations. We find increases in CH4 sources balanced by increases in sinks lead to CH4 stabilization during 1999–2006, and anthropogenic sources (e.g., agriculture, energy, and waste) are more likely major contributors to the renewed growth after 2006. Increases in CH4 emissions and decreases in OH levels during 2008–2015 prolong CH4 lifetime and amplify methane response to emission changes.
Bing Pu, Paul Ginoux, Huan Guo, N. Christina Hsu, John Kimball, Beatrice Marticorena, Sergey Malyshev, Vaishali Naik, Norman T. O'Neill, Carlos Pérez García-Pando, Juliette Paireau, Joseph M. Prospero, Elena Shevliakova, and Ming Zhao
Atmos. Chem. Phys., 20, 55–81, https://doi.org/10.5194/acp-20-55-2020, https://doi.org/10.5194/acp-20-55-2020, 2020
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Dust emission initiates when surface wind velocities exceed a threshold depending on soil and surface characteristics and varying spatially and temporally. Climate models widely use wind erosion thresholds. The climatological monthly global distribution of the wind erosion threshold, Vthreshold, is retrieved using satellite and reanalysis products and improves the simulation of dust frequency, magnitude, and the seasonal cycle in the Geophysical Fluid Dynamics Laboratory land–atmosphere model.
Fabien Paulot, Sergey Malyshev, Tran Nguyen, John D. Crounse, Elena Shevliakova, and Larry W. Horowitz
Atmos. Chem. Phys., 18, 17963–17978, https://doi.org/10.5194/acp-18-17963-2018, https://doi.org/10.5194/acp-18-17963-2018, 2018
Ilissa B. Ocko, Vaishali Naik, and David Paynter
Atmos. Chem. Phys., 18, 15555–15568, https://doi.org/10.5194/acp-18-15555-2018, https://doi.org/10.5194/acp-18-15555-2018, 2018
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As communities worldwide analyse options to reduce methane emissions from energy use, agriculture, and waste management, there is an immediate need to build confidence in rapid assessment tools other than standard climate metrics – which misrepresent impacts over all timescales. In this paper, we show that a simplified climate model can easily and rapidly provide scientifically robust climate responses to changes in methane emissions, thereby improving mitigation analysis and decision-making.
Arlene M. Fiore, Emily V. Fischer, George P. Milly, Shubha Pandey Deolal, Oliver Wild, Daniel A. Jaffe, Johannes Staehelin, Olivia E. Clifton, Dan Bergmann, William Collins, Frank Dentener, Ruth M. Doherty, Bryan N. Duncan, Bernd Fischer, Stefan Gilge, Peter G. Hess, Larry W. Horowitz, Alexandru Lupu, Ian A. MacKenzie, Rokjin Park, Ludwig Ries, Michael G. Sanderson, Martin G. Schultz, Drew T. Shindell, Martin Steinbacher, David S. Stevenson, Sophie Szopa, Christoph Zellweger, and Guang Zeng
Atmos. Chem. Phys., 18, 15345–15361, https://doi.org/10.5194/acp-18-15345-2018, https://doi.org/10.5194/acp-18-15345-2018, 2018
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We demonstrate a proof-of-concept approach for applying northern midlatitude mountaintop peroxy acetyl nitrate (PAN) measurements and a multi-model ensemble during April to constrain the influence of continental-scale anthropogenic precursor emissions on PAN. Our findings imply a role for carefully coordinated multi-model ensembles in helping identify observations for discriminating among widely varying (and poorly constrained) model responses of atmospheric constituents to changes in emissions.
Fabien Paulot, David Paynter, Paul Ginoux, Vaishali Naik, and Larry W. Horowitz
Atmos. Chem. Phys., 18, 13265–13281, https://doi.org/10.5194/acp-18-13265-2018, https://doi.org/10.5194/acp-18-13265-2018, 2018
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Observations show that the sunlight reflected to space by particles has decreased over the US and Europe, increased over India, and not changed over China from 2001 to 2015. These changes are attributed to different types of particles, namely sulfate over the US and Europe, and black carbon, sulfate, and nitrate over China and India. Our results suggest that the recent shift in human emissions from the US and Europe to Asia has altered their impact on the Earth's outgoing energy.
Daniel M. Westervelt, Andrew J. Conley, Arlene M. Fiore, Jean-François Lamarque, Drew T. Shindell, Michael Previdi, Nora R. Mascioli, Greg Faluvegi, Gustavo Correa, and Larry W. Horowitz
Atmos. Chem. Phys., 18, 12461–12475, https://doi.org/10.5194/acp-18-12461-2018, https://doi.org/10.5194/acp-18-12461-2018, 2018
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Small particles in Earth's atmosphere (also referred to as atmospheric aerosols) emitted by human activities impact Earth's climate in complex ways and play an important role in Earth's water cycle. We use a climate modeling approach and find that aerosols from the United States and Europe can have substantial effects on rainfall in far-away regions such as Africa's Sahel or the Mediterranean. Air pollution controls in these regions may help reduce the likelihood and severity of Sahel drought.
Jordan L. Schnell, Vaishali Naik, Larry W. Horowitz, Fabien Paulot, Jingqiu Mao, Paul Ginoux, Ming Zhao, and Kirpa Ram
Atmos. Chem. Phys., 18, 10157–10175, https://doi.org/10.5194/acp-18-10157-2018, https://doi.org/10.5194/acp-18-10157-2018, 2018
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We evaluate the ability of a developmental version of the NOAA GFDL Atmospheric Model, version 4 to simulate observed wintertime pollution and its relationship to weather over Northern India, one of the most densely populated and polluted regions in world. We also compare two emission inventories and find that the newest version dramatically improves our simulation. Observed and modeled pollution is the highest within the Indo-Gangetic Plain, where it is closely related to near-surface weather.
Sandip S. Dhomse, Douglas Kinnison, Martyn P. Chipperfield, Ross J. Salawitch, Irene Cionni, Michaela I. Hegglin, N. Luke Abraham, Hideharu Akiyoshi, Alex T. Archibald, Ewa M. Bednarz, Slimane Bekki, Peter Braesicke, Neal Butchart, Martin Dameris, Makoto Deushi, Stacey Frith, Steven C. Hardiman, Birgit Hassler, Larry W. Horowitz, Rong-Ming Hu, Patrick Jöckel, Beatrice Josse, Oliver Kirner, Stefanie Kremser, Ulrike Langematz, Jared Lewis, Marion Marchand, Meiyun Lin, Eva Mancini, Virginie Marécal, Martine Michou, Olaf Morgenstern, Fiona M. O'Connor, Luke Oman, Giovanni Pitari, David A. Plummer, John A. Pyle, Laura E. Revell, Eugene Rozanov, Robyn Schofield, Andrea Stenke, Kane Stone, Kengo Sudo, Simone Tilmes, Daniele Visioni, Yousuke Yamashita, and Guang Zeng
Atmos. Chem. Phys., 18, 8409–8438, https://doi.org/10.5194/acp-18-8409-2018, https://doi.org/10.5194/acp-18-8409-2018, 2018
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We analyse simulations from the Chemistry-Climate Model Initiative (CCMI) to estimate the return dates of the stratospheric ozone layer from depletion by anthropogenic chlorine and bromine. The simulations from 20 models project that global column ozone will return to 1980 values in 2047 (uncertainty range 2042–2052). Return dates in other regions vary depending on factors related to climate change and importance of chlorine and bromine. Column ozone in the tropics may continue to decline.
Jingqiu Mao, Annmarie Carlton, Ronald C. Cohen, William H. Brune, Steven S. Brown, Glenn M. Wolfe, Jose L. Jimenez, Havala O. T. Pye, Nga Lee Ng, Lu Xu, V. Faye McNeill, Kostas Tsigaridis, Brian C. McDonald, Carsten Warneke, Alex Guenther, Matthew J. Alvarado, Joost de Gouw, Loretta J. Mickley, Eric M. Leibensperger, Rohit Mathur, Christopher G. Nolte, Robert W. Portmann, Nadine Unger, Mika Tosca, and Larry W. Horowitz
Atmos. Chem. Phys., 18, 2615–2651, https://doi.org/10.5194/acp-18-2615-2018, https://doi.org/10.5194/acp-18-2615-2018, 2018
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This paper is aimed at discussing progress in evaluating, diagnosing, and improving air quality and climate modeling using comparisons to SAS observations as a guide to thinking about improvements to mechanisms and parameterizations in models.
Jingyi Li, Jingqiu Mao, Arlene M. Fiore, Ronald C. Cohen, John D. Crounse, Alex P. Teng, Paul O. Wennberg, Ben H. Lee, Felipe D. Lopez-Hilfiker, Joel A. Thornton, Jeff Peischl, Ilana B. Pollack, Thomas B. Ryerson, Patrick Veres, James M. Roberts, J. Andrew Neuman, John B. Nowak, Glenn M. Wolfe, Thomas F. Hanisco, Alan Fried, Hanwant B. Singh, Jack Dibb, Fabien Paulot, and Larry W. Horowitz
Atmos. Chem. Phys., 18, 2341–2361, https://doi.org/10.5194/acp-18-2341-2018, https://doi.org/10.5194/acp-18-2341-2018, 2018
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We present the first comprehensive model evaluation of summertime reactive oxidized nitrogen using a high-resolution chemistry–climate model with up-to-date isoprene oxidation chemistry, along with a series of observations from aircraft campaigns and ground measurement networks from 2004 to 2013 over the Southeast US. We investigate the impact of NOx emission reductions on changes in reactive nitrogen speciation and export efficiency as well as ozone in the past and future decade.
Marielle Saunois, Philippe Bousquet, Ben Poulter, Anna Peregon, Philippe Ciais, Josep G. Canadell, Edward J. Dlugokencky, Giuseppe Etiope, David Bastviken, Sander Houweling, Greet Janssens-Maenhout, Francesco N. Tubiello, Simona Castaldi, Robert B. Jackson, Mihai Alexe, Vivek K. Arora, David J. Beerling, Peter Bergamaschi, Donald R. Blake, Gordon Brailsford, Lori Bruhwiler, Cyril Crevoisier, Patrick Crill, Kristofer Covey, Christian Frankenberg, Nicola Gedney, Lena Höglund-Isaksson, Misa Ishizawa, Akihiko Ito, Fortunat Joos, Heon-Sook Kim, Thomas Kleinen, Paul Krummel, Jean-François Lamarque, Ray Langenfelds, Robin Locatelli, Toshinobu Machida, Shamil Maksyutov, Joe R. Melton, Isamu Morino, Vaishali Naik, Simon O'Doherty, Frans-Jan W. Parmentier, Prabir K. Patra, Changhui Peng, Shushi Peng, Glen P. Peters, Isabelle Pison, Ronald Prinn, Michel Ramonet, William J. Riley, Makoto Saito, Monia Santini, Ronny Schroeder, Isobel J. Simpson, Renato Spahni, Atsushi Takizawa, Brett F. Thornton, Hanqin Tian, Yasunori Tohjima, Nicolas Viovy, Apostolos Voulgarakis, Ray Weiss, David J. Wilton, Andy Wiltshire, Doug Worthy, Debra Wunch, Xiyan Xu, Yukio Yoshida, Bowen Zhang, Zhen Zhang, and Qiuan Zhu
Atmos. Chem. Phys., 17, 11135–11161, https://doi.org/10.5194/acp-17-11135-2017, https://doi.org/10.5194/acp-17-11135-2017, 2017
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Following the Global Methane Budget 2000–2012 published in Saunois et al. (2016), we use the same dataset of bottom-up and top-down approaches to discuss the variations in methane emissions over the period 2000–2012. The changes in emissions are discussed both in terms of trends and quasi-decadal changes. The ensemble gathered here allows us to synthesise the robust changes in terms of regional and sectorial contributions to the increasing methane emissions.
Michael J. Prather, Xin Zhu, Clare M. Flynn, Sarah A. Strode, Jose M. Rodriguez, Stephen D. Steenrod, Junhua Liu, Jean-Francois Lamarque, Arlene M. Fiore, Larry W. Horowitz, Jingqiu Mao, Lee T. Murray, Drew T. Shindell, and Steven C. Wofsy
Atmos. Chem. Phys., 17, 9081–9102, https://doi.org/10.5194/acp-17-9081-2017, https://doi.org/10.5194/acp-17-9081-2017, 2017
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We present a new approach for comparing atmospheric chemistry models with measurements based on what these models are used to do, i.e., calculate changes in ozone and methane, prime greenhouse gases. This method anticipates a new type of measurements from the NASA Atmospheric Tomography (ATom) mission. In comparing the mixture of species within air parcels, we focus on those responsible for key chemical changes and weight these parcels by their chemical reactivity.
Hyun-Deok Choi, Hongyu Liu, James H. Crawford, David B. Considine, Dale J. Allen, Bryan N. Duncan, Larry W. Horowitz, Jose M. Rodriguez, Susan E. Strahan, Lin Zhang, Xiong Liu, Megan R. Damon, and Stephen D. Steenrod
Atmos. Chem. Phys., 17, 8429–8452, https://doi.org/10.5194/acp-17-8429-2017, https://doi.org/10.5194/acp-17-8429-2017, 2017
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We evaluate global ozone–carbon monoxide (O3–CO) correlations in a chemistry and transport model during July–August with TES-Aura satellite observations and examine the sensitivity of model simulations to input meteorological data and emissions. Results show that O3–CO correlations may be used effectively to constrain the sources of regional tropospheric O3 in global 3-D models, especially for those regions where convective transport of pollution plays an important role.
Eri Saikawa, Hankyul Kim, Min Zhong, Alexander Avramov, Yu Zhao, Greet Janssens-Maenhout, Jun-ichi Kurokawa, Zbigniew Klimont, Fabian Wagner, Vaishali Naik, Larry W. Horowitz, and Qiang Zhang
Atmos. Chem. Phys., 17, 6393–6421, https://doi.org/10.5194/acp-17-6393-2017, https://doi.org/10.5194/acp-17-6393-2017, 2017
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We analyze differences in existing air pollutant emission estimates to better understand the magnitude of emissions as well as the source regions and sectors of air pollution in China. We find large disagreements among the inventories, and we show that these differences have a significant impact on regional air quality simulations. Better understanding of air pollutant emissions at more disaggregated levels is essential for air pollution mitigation in China.
Meiyun Lin, Larry W. Horowitz, Richard Payton, Arlene M. Fiore, and Gail Tonnesen
Atmos. Chem. Phys., 17, 2943–2970, https://doi.org/10.5194/acp-17-2943-2017, https://doi.org/10.5194/acp-17-2943-2017, 2017
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US ozone pollution responds to varying global-to-regional precursor emissions and climate, with implications for designing effective air quality control policies. Asian anthropogenic emissions of ozone precursors tripled since 1990, contributing 65 % to western US ozone increases in spring, outpacing ozone decreases attained via 50 % US emission controls. In the eastern US, if emissions had not declined, more frequent hot extremes since 1990 would have worsened the highest ozone events in summer.
Olaf Morgenstern, Michaela I. Hegglin, Eugene Rozanov, Fiona M. O'Connor, N. Luke Abraham, Hideharu Akiyoshi, Alexander T. Archibald, Slimane Bekki, Neal Butchart, Martyn P. Chipperfield, Makoto Deushi, Sandip S. Dhomse, Rolando R. Garcia, Steven C. Hardiman, Larry W. Horowitz, Patrick Jöckel, Beatrice Josse, Douglas Kinnison, Meiyun Lin, Eva Mancini, Michael E. Manyin, Marion Marchand, Virginie Marécal, Martine Michou, Luke D. Oman, Giovanni Pitari, David A. Plummer, Laura E. Revell, David Saint-Martin, Robyn Schofield, Andrea Stenke, Kane Stone, Kengo Sudo, Taichu Y. Tanaka, Simone Tilmes, Yousuke Yamashita, Kohei Yoshida, and Guang Zeng
Geosci. Model Dev., 10, 639–671, https://doi.org/10.5194/gmd-10-639-2017, https://doi.org/10.5194/gmd-10-639-2017, 2017
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We present a review of the make-up of 20 models participating in the Chemistry–Climate Model Initiative (CCMI). In comparison to earlier such activities, most of these models comprise a whole-atmosphere chemistry, and several of them include an interactive ocean module. This makes them suitable for studying the interactions of tropospheric air quality, stratospheric ozone, and climate. The paper lays the foundation for other studies using the CCMI simulations for scientific analysis.
Marielle Saunois, Philippe Bousquet, Ben Poulter, Anna Peregon, Philippe Ciais, Josep G. Canadell, Edward J. Dlugokencky, Giuseppe Etiope, David Bastviken, Sander Houweling, Greet Janssens-Maenhout, Francesco N. Tubiello, Simona Castaldi, Robert B. Jackson, Mihai Alexe, Vivek K. Arora, David J. Beerling, Peter Bergamaschi, Donald R. Blake, Gordon Brailsford, Victor Brovkin, Lori Bruhwiler, Cyril Crevoisier, Patrick Crill, Kristofer Covey, Charles Curry, Christian Frankenberg, Nicola Gedney, Lena Höglund-Isaksson, Misa Ishizawa, Akihiko Ito, Fortunat Joos, Heon-Sook Kim, Thomas Kleinen, Paul Krummel, Jean-François Lamarque, Ray Langenfelds, Robin Locatelli, Toshinobu Machida, Shamil Maksyutov, Kyle C. McDonald, Julia Marshall, Joe R. Melton, Isamu Morino, Vaishali Naik, Simon O'Doherty, Frans-Jan W. Parmentier, Prabir K. Patra, Changhui Peng, Shushi Peng, Glen P. Peters, Isabelle Pison, Catherine Prigent, Ronald Prinn, Michel Ramonet, William J. Riley, Makoto Saito, Monia Santini, Ronny Schroeder, Isobel J. Simpson, Renato Spahni, Paul Steele, Atsushi Takizawa, Brett F. Thornton, Hanqin Tian, Yasunori Tohjima, Nicolas Viovy, Apostolos Voulgarakis, Michiel van Weele, Guido R. van der Werf, Ray Weiss, Christine Wiedinmyer, David J. Wilton, Andy Wiltshire, Doug Worthy, Debra Wunch, Xiyan Xu, Yukio Yoshida, Bowen Zhang, Zhen Zhang, and Qiuan Zhu
Earth Syst. Sci. Data, 8, 697–751, https://doi.org/10.5194/essd-8-697-2016, https://doi.org/10.5194/essd-8-697-2016, 2016
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An accurate assessment of the methane budget is important to understand the atmospheric methane concentrations and trends and to provide realistic pathways for climate change mitigation. The various and diffuse sources of methane as well and its oxidation by a very short lifetime radical challenge this assessment. We quantify the methane sources and sinks as well as their uncertainties based on both bottom-up and top-down approaches provided by a broad international scientific community.
Raquel A. Silva, J. Jason West, Jean-François Lamarque, Drew T. Shindell, William J. Collins, Stig Dalsoren, Greg Faluvegi, Gerd Folberth, Larry W. Horowitz, Tatsuya Nagashima, Vaishali Naik, Steven T. Rumbold, Kengo Sudo, Toshihiko Takemura, Daniel Bergmann, Philip Cameron-Smith, Irene Cionni, Ruth M. Doherty, Veronika Eyring, Beatrice Josse, Ian A. MacKenzie, David Plummer, Mattia Righi, David S. Stevenson, Sarah Strode, Sophie Szopa, and Guang Zengast
Atmos. Chem. Phys., 16, 9847–9862, https://doi.org/10.5194/acp-16-9847-2016, https://doi.org/10.5194/acp-16-9847-2016, 2016
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Using ozone and PM2.5 concentrations from the ACCMIP ensemble of chemistry-climate models for the four Representative Concentration Pathway scenarios (RCPs), together with projections of future population and baseline mortality rates, we quantify the human premature mortality impacts of future ambient air pollution in 2030, 2050 and 2100, relative to 2000 concentrations. We also estimate the global mortality burden of ozone and PM2.5 in 2000 and each future period.
Yuqiang Zhang, Jared H. Bowden, Zachariah Adelman, Vaishali Naik, Larry W. Horowitz, Steven J. Smith, and J. Jason West
Atmos. Chem. Phys., 16, 9533–9548, https://doi.org/10.5194/acp-16-9533-2016, https://doi.org/10.5194/acp-16-9533-2016, 2016
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Reducing greenhouse gas (GHG) emissions can also improve air quality. We estimate the co-benefits of global GHG mitigation for US air quality in 2050 at fine resolution by downscaling from a previous global study. Foreign GHG mitigation under RCP4.5 contributes more to the US O3 reduction (76 % of the total) than domestic mitigation and contributes 26 % of the PM2.5 reduction. Therefore, the US gains significantly greater air quality co-benefits by coordinating GHG controls internationally.
Hongyu Liu, David B. Considine, Larry W. Horowitz, James H. Crawford, Jose M. Rodriguez, Susan E. Strahan, Megan R. Damon, Stephen D. Steenrod, Xiaojing Xu, Jules Kouatchou, Claire Carouge, and Robert M. Yantosca
Atmos. Chem. Phys., 16, 4641–4659, https://doi.org/10.5194/acp-16-4641-2016, https://doi.org/10.5194/acp-16-4641-2016, 2016
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We assess the utility of cosmogenic beryllium-7, a natural aerosol tracer, for evaluating cross-tropopause transport in global models. We show that model excessive cross-tropopause transport of beryllium-7 corresponds to overestimated stratospheric contribution to tropospheric ozone. We conclude that the observational constraints for beryllium-7 and observed beryllium-7 total deposition fluxes can be used routinely as a first-order assessment of cross-tropopause transport in global models.
Min Zhong, Eri Saikawa, Yang Liu, Vaishali Naik, Larry W. Horowitz, Masayuki Takigawa, Yu Zhao, Neng-Huei Lin, and Elizabeth A. Stone
Geosci. Model Dev., 9, 1201–1218, https://doi.org/10.5194/gmd-9-1201-2016, https://doi.org/10.5194/gmd-9-1201-2016, 2016
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Large discrepancies exist among emission inventories (e.g., REAS and EDGAR) at the provincial level in China. We use WRF-Chem to evaluate the impact of the difference in existing emission inventories and find that emissions inputs significantly affect our air pollutant simulation results. Our study highlights the importance of constraining emissions at the provincial level for regional air quality modeling over East Asia.
G. M. Wolfe, J. Kaiser, T. F. Hanisco, F. N. Keutsch, J. A. de Gouw, J. B. Gilman, M. Graus, C. D. Hatch, J. Holloway, L. W. Horowitz, B. H. Lee, B. M. Lerner, F. Lopez-Hilifiker, J. Mao, M. R. Marvin, J. Peischl, I. B. Pollack, J. M. Roberts, T. B. Ryerson, J. A. Thornton, P. R. Veres, and C. Warneke
Atmos. Chem. Phys., 16, 2597–2610, https://doi.org/10.5194/acp-16-2597-2016, https://doi.org/10.5194/acp-16-2597-2016, 2016
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This study uses airborne trace gas observations acquired over the southeast US to examine how both natural (isoprene) and anthropogenic (NOx) emissions influence the production of formaldehyde (HCHO). We find a 3-fold increase in HCHO yield between rural and polluted environments. State-of-the-science chemical mechanisms are generally able to reproduce this behavior. These results add confidence to global hydrocarbon emission inventories constrained by spaceborne HCHO observations.
F. Paulot, P. Ginoux, W. F. Cooke, L. J. Donner, S. Fan, M.-Y. Lin, J. Mao, V. Naik, and L. W. Horowitz
Atmos. Chem. Phys., 16, 1459–1477, https://doi.org/10.5194/acp-16-1459-2016, https://doi.org/10.5194/acp-16-1459-2016, 2016
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We characterize the sensitivity of NO3 optical depth (OD) to both the sources of its precursors (NH3 and HNO3) and to its surface sinks. Uncertainties in the heterogeneous chemistry of HNO3 and the near-surface volatilization of NH4NO3 can cause up to 25 % difference in the global NO3 OD. Simulated NO3 OD increases little (< 30 %) in response to changes in emissions (2010 to 2050). Better constraints on the tropical flux of NH3 into the free troposphere are needed to improve estimates of NO3 OD.
D. M. Westervelt, L. W. Horowitz, V. Naik, J.-C. Golaz, and D. L. Mauzerall
Atmos. Chem. Phys., 15, 12681–12703, https://doi.org/10.5194/acp-15-12681-2015, https://doi.org/10.5194/acp-15-12681-2015, 2015
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Decreases in aerosols over the 21st century as projected by the Representative Concentration Pathways (RCPs) lead to increases up to 0.5 - 1 ºC in global temperature and up to 0.05 - 0.1 mm/day in global precipitation, depending strongly on present-day aerosol radiative forcing. In East Asia, future aerosol decreases could be responsible for 10-20% of the total temperature increase (30-40% with strong present-day aerosol forcing), even under the high greenhouse gas emissions scenario (RCP8.5).
J. L. Schnell, M. J. Prather, B. Josse, V. Naik, L. W. Horowitz, P. Cameron-Smith, D. Bergmann, G. Zeng, D. A. Plummer, K. Sudo, T. Nagashima, D. T. Shindell, G. Faluvegi, and S. A. Strode
Atmos. Chem. Phys., 15, 10581–10596, https://doi.org/10.5194/acp-15-10581-2015, https://doi.org/10.5194/acp-15-10581-2015, 2015
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We test global chemistry--climate models in their ability to simulate present-day surface ozone. Models are tested against observed hourly ozone from 4217 stations in North America and Europe that are averaged over 1°x1° grid cells. Using novel metrics, we find most models match the shape but not the amplitude of regional summertime diurnal and annual cycles and match the pattern but not the magnitude of summer ozone enhancement. Most also match the observed distribution of extreme episode sizes
Z. Shen, J. Liu, L. W. Horowitz, D. K. Henze, S. Fan, Levy II H., D. L. Mauzerall, J.-T. Lin, and S. Tao
Atmos. Chem. Phys., 14, 6315–6327, https://doi.org/10.5194/acp-14-6315-2014, https://doi.org/10.5194/acp-14-6315-2014, 2014
M. M. Fry, M. D. Schwarzkopf, Z. Adelman, V. Naik, W. J. Collins, and J. J. West
Atmos. Chem. Phys., 13, 5381–5399, https://doi.org/10.5194/acp-13-5381-2013, https://doi.org/10.5194/acp-13-5381-2013, 2013
V. Naik, A. Voulgarakis, A. M. Fiore, L. W. Horowitz, J.-F. Lamarque, M. Lin, M. J. Prather, P. J. Young, D. Bergmann, P. J. Cameron-Smith, I. Cionni, W. J. Collins, S. B. Dalsøren, R. Doherty, V. Eyring, G. Faluvegi, G. A. Folberth, B. Josse, Y. H. Lee, I. A. MacKenzie, T. Nagashima, T. P. C. van Noije, D. A. Plummer, M. Righi, S. T. Rumbold, R. Skeie, D. T. Shindell, D. S. Stevenson, S. Strode, K. Sudo, S. Szopa, and G. Zeng
Atmos. Chem. Phys., 13, 5277–5298, https://doi.org/10.5194/acp-13-5277-2013, https://doi.org/10.5194/acp-13-5277-2013, 2013
K. W. Bowman, D. T. Shindell, H. M. Worden, J.F. Lamarque, P. J. Young, D. S. Stevenson, Z. Qu, M. de la Torre, D. Bergmann, P. J. Cameron-Smith, W. J. Collins, R. Doherty, S. B. Dalsøren, G. Faluvegi, G. Folberth, L. W. Horowitz, B. M. Josse, Y. H. Lee, I. A. MacKenzie, G. Myhre, T. Nagashima, V. Naik, D. A. Plummer, S. T. Rumbold, R. B. Skeie, S. A. Strode, K. Sudo, S. Szopa, A. Voulgarakis, G. Zeng, S. S. Kulawik, A. M. Aghedo, and J. R. Worden
Atmos. Chem. Phys., 13, 4057–4072, https://doi.org/10.5194/acp-13-4057-2013, https://doi.org/10.5194/acp-13-4057-2013, 2013
D. T. Shindell, J.-F. Lamarque, M. Schulz, M. Flanner, C. Jiao, M. Chin, P. J. Young, Y. H. Lee, L. Rotstayn, N. Mahowald, G. Milly, G. Faluvegi, Y. Balkanski, W. J. Collins, A. J. Conley, S. Dalsoren, R. Easter, S. Ghan, L. Horowitz, X. Liu, G. Myhre, T. Nagashima, V. Naik, S. T. Rumbold, R. Skeie, K. Sudo, S. Szopa, T. Takemura, A. Voulgarakis, J.-H. Yoon, and F. Lo
Atmos. Chem. Phys., 13, 2939–2974, https://doi.org/10.5194/acp-13-2939-2013, https://doi.org/10.5194/acp-13-2939-2013, 2013
D. S. Stevenson, P. J. Young, V. Naik, J.-F. Lamarque, D. T. Shindell, A. Voulgarakis, R. B. Skeie, S. B. Dalsoren, G. Myhre, T. K. Berntsen, G. A. Folberth, S. T. Rumbold, W. J. Collins, I. A. MacKenzie, R. M. Doherty, G. Zeng, T. P. C. van Noije, A. Strunk, D. Bergmann, P. Cameron-Smith, D. A. Plummer, S. A. Strode, L. Horowitz, Y. H. Lee, S. Szopa, K. Sudo, T. Nagashima, B. Josse, I. Cionni, M. Righi, V. Eyring, A. Conley, K. W. Bowman, O. Wild, and A. Archibald
Atmos. Chem. Phys., 13, 3063–3085, https://doi.org/10.5194/acp-13-3063-2013, https://doi.org/10.5194/acp-13-3063-2013, 2013
Y. H. Lee, J.-F. Lamarque, M. G. Flanner, C. Jiao, D. T. Shindell, T. Berntsen, M. M. Bisiaux, J. Cao, W. J. Collins, M. Curran, R. Edwards, G. Faluvegi, S. Ghan, L. W. Horowitz, J. R. McConnell, J. Ming, G. Myhre, T. Nagashima, V. Naik, S. T. Rumbold, R. B. Skeie, K. Sudo, T. Takemura, F. Thevenon, B. Xu, and J.-H. Yoon
Atmos. Chem. Phys., 13, 2607–2634, https://doi.org/10.5194/acp-13-2607-2013, https://doi.org/10.5194/acp-13-2607-2013, 2013
A. Voulgarakis, V. Naik, J.-F. Lamarque, D. T. Shindell, P. J. Young, M. J. Prather, O. Wild, R. D. Field, D. Bergmann, P. Cameron-Smith, I. Cionni, W. J. Collins, S. B. Dalsøren, R. M. Doherty, V. Eyring, G. Faluvegi, G. A. Folberth, L. W. Horowitz, B. Josse, I. A. MacKenzie, T. Nagashima, D. A. Plummer, M. Righi, S. T. Rumbold, D. S. Stevenson, S. A. Strode, K. Sudo, S. Szopa, and G. Zeng
Atmos. Chem. Phys., 13, 2563–2587, https://doi.org/10.5194/acp-13-2563-2013, https://doi.org/10.5194/acp-13-2563-2013, 2013
P. J. Young, A. T. Archibald, K. W. Bowman, J.-F. Lamarque, V. Naik, D. S. Stevenson, S. Tilmes, A. Voulgarakis, O. Wild, D. Bergmann, P. Cameron-Smith, I. Cionni, W. J. Collins, S. B. Dalsøren, R. M. Doherty, V. Eyring, G. Faluvegi, L. W. Horowitz, B. Josse, Y. H. Lee, I. A. MacKenzie, T. Nagashima, D. A. Plummer, M. Righi, S. T. Rumbold, R. B. Skeie, D. T. Shindell, S. A. Strode, K. Sudo, S. Szopa, and G. Zeng
Atmos. Chem. Phys., 13, 2063–2090, https://doi.org/10.5194/acp-13-2063-2013, https://doi.org/10.5194/acp-13-2063-2013, 2013
C. He, J. Liu, A. G. Carlton, S. Fan, L. W. Horowitz, H. Levy II, and S. Tao
Atmos. Chem. Phys., 13, 1913–1926, https://doi.org/10.5194/acp-13-1913-2013, https://doi.org/10.5194/acp-13-1913-2013, 2013
J.-F. Lamarque, D. T. Shindell, B. Josse, P. J. Young, I. Cionni, V. Eyring, D. Bergmann, P. Cameron-Smith, W. J. Collins, R. Doherty, S. Dalsoren, G. Faluvegi, G. Folberth, S. J. Ghan, L. W. Horowitz, Y. H. Lee, I. A. MacKenzie, T. Nagashima, V. Naik, D. Plummer, M. Righi, S. T. Rumbold, M. Schulz, R. B. Skeie, D. S. Stevenson, S. Strode, K. Sudo, S. Szopa, A. Voulgarakis, and G. Zeng
Geosci. Model Dev., 6, 179–206, https://doi.org/10.5194/gmd-6-179-2013, https://doi.org/10.5194/gmd-6-179-2013, 2013
Y. Fang, V. Naik, L. W. Horowitz, and D. L. Mauzerall
Atmos. Chem. Phys., 13, 1377–1394, https://doi.org/10.5194/acp-13-1377-2013, https://doi.org/10.5194/acp-13-1377-2013, 2013
A. J. Turner, A. M. Fiore, L. W. Horowitz, and M. Bauer
Atmos. Chem. Phys., 13, 565–578, https://doi.org/10.5194/acp-13-565-2013, https://doi.org/10.5194/acp-13-565-2013, 2013
J. G. John, A. M. Fiore, V. Naik, L. W. Horowitz, and J. P. Dunne
Atmos. Chem. Phys., 12, 12021–12036, https://doi.org/10.5194/acp-12-12021-2012, https://doi.org/10.5194/acp-12-12021-2012, 2012
Related subject area
Subject: Gases | Research Activity: Atmospheric Modelling and Data Analysis | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
Regional and sectoral contributions of NOx and reactive carbon emission sources to global trends in tropospheric ozone during the 2000–2018 period
Underappreciated contributions of biogenic volatile organic compounds from urban green spaces to ozone pollution
Chemistry–climate feedback of atmospheric methane in a methane-emission-flux-driven chemistry–climate model
Surface ozone trend variability across the United States and the impact of heat waves (1990–2023)
Sensitivity of climate effects of hydrogen to leakage size, location, and chemical background
Evaluating tropospheric nitrogen dioxide in UKCA using OMI satellite retrievals over south and east Asia
Technical note: A comparative study of chemistry schemes for volcanic sulfur dioxide in Lagrangian transport simulations – a case study of the 2019 Raikoke eruption
Revisiting the high tropospheric ozone over southern Africa: role of biomass burning and anthropogenic emissions
Monoterpene oxidation pathways initiated by acyl peroxy radical addition
Local and transboundary contributions to NOy loadings across East Asia using CMAQ-ISAM and a GEMS-informed emission inventory during the winter–spring transition
Estimating the variability in NOx emissions from Wuhan with TROPOMI NO2 data during 2018 to 2023
Enhanced understanding of atmospheric blocking modulation on ozone dynamics within a high-resolution Earth system model
Natural emissions of VOC and NOx over Africa constrained by TROPOMI HCHO and NO2 data using the MAGRITTEv1.1 model
Contributions of lightning to long-term trends and inter-annual variability in global atmospheric chemistry constrained by Schumann Resonance observations
Impacts of wildfire smoke aerosols on near-surface ozone photochemistry
Anthropogenic emission controls reduce summertime ozone–temperature sensitivity in the United States
Investigating the response of China's surface ozone concentration to the future changes of multiple factors
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
Air-pollution-satellite-based CO2 emission inversion: system evaluation, sensitivity analysis, and future research direction
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
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
Modelling Arctic Lower Tropospheric Ozone: processes controlling seasonal variations
South Asia ammonia emission inversion through assimilating IASI observations
Constraining the budget of NOx and VOCs at a remote Tropical island using multi-platform observations and WRF-Chem model simulations
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)
Comparative ozone production sensitivity to NOx and VOCs in Quito, Ecuador and Santiago, Chile: implications for control strategies in times of climate action
Seasonal, regional, and vertical characteristics of high-carbon-monoxide plumes along with their associated ozone anomalies, as seen by IAGOS between 2002 and 2019
Tropospheric ozone trends and attributions over East and Southeast Asia in 1995–2019: An integrated assessment using statistical methods, machine learning models, and multiple chemical transport models
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
Sensitivity of climate-chemistry model simulated atmospheric composition to lightning-produced NOx parameterizations based on lightning frequency
Ozone source attribution in polluted European areas during summer 2017 as simulated with MECO(n)
Characterization of reactive nitrogen in the global upper troposphere using recent and historical commercial and research aircraft campaigns and GEOS-Chem
Opinion: Challenges and needs of tropospheric chemical mechanism development
Decrease of the European NOx anthropogenic emissions between 2005 and 2019 as seen from the OMI and TROPOMI NO2 satellite observations
Tracking daily NOx emissions from an urban agglomeration based on TROPOMI NO2 and a local ensemble transform Kalman filter
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
Aditya Nalam, Aura Lupaşcu, Tabish Ansari, and Tim Butler
Atmos. Chem. Phys., 25, 5287–5311, https://doi.org/10.5194/acp-25-5287-2025, https://doi.org/10.5194/acp-25-5287-2025, 2025
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Tropospheric O3 molecules are labeled with the identity of their precursor source to simulate contributions from various emission sources to the global tropospheric O3 burden (TOB) and its trends. With an equatorward shift, anthropogenic NOx emissions become significantly more efficient at producing O3 and play a major role in driving TOB trends, mainly due to larger convection at the tropics effectively lifting O3 and its precursors to the free troposphere, where O3 lifetime is longer.
Haofan Wang, Yuejin Li, Yiming Liu, Xiao Lu, Yang Zhang, Qi Fan, Chong Shen, Senchao Lai, Yan Zhou, Tao Zhang, and Dingli Yue
Atmos. Chem. Phys., 25, 5233–5250, https://doi.org/10.5194/acp-25-5233-2025, https://doi.org/10.5194/acp-25-5233-2025, 2025
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This study explores how urban green spaces (UGSs) in Guangzhou influence ozone levels. By using advanced models, we found that natural emissions from these areas can significantly affect air quality. Our results suggest that the design and planning of UGSs should not only consider aesthetics and social factors but also their environmental impacts on air quality.
Laura Stecher, Franziska Winterstein, Patrick Jöckel, Michael Ponater, Mariano Mertens, and Martin Dameris
Atmos. Chem. Phys., 25, 5133–5158, https://doi.org/10.5194/acp-25-5133-2025, https://doi.org/10.5194/acp-25-5133-2025, 2025
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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 in the chemical sink in a warming climate and its implications for the chemical composition and the surface air temperature change.
Kai-Lan Chang, Brian C. McDonald, Colin Harkins, and Owen R. Cooper
Atmos. Chem. Phys., 25, 5101–5132, https://doi.org/10.5194/acp-25-5101-2025, https://doi.org/10.5194/acp-25-5101-2025, 2025
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Exposure to high levels of ozone can be harmful to human health. This study shows consistent and robust evidence of decreasing ozone extremes across much of the United States over the period from 1990 to 2023, previously attributed to ozone precursor emission controls. Nevertheless, we also show that the increasing heat wave frequencies are likely to contribute to additional ozone exceedances, slowing the progress of decreasing the frequency of ozone exceedances.
Ragnhild Bieltvedt Skeie, Marit Sandstad, Srinath Krishnan, Gunnar Myhre, and Maria Sand
Atmos. Chem. Phys., 25, 4929–4942, https://doi.org/10.5194/acp-25-4929-2025, https://doi.org/10.5194/acp-25-4929-2025, 2025
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Hydrogen leakages can alter the amount of climate gases in the atmosphere and hence have a climate impact. In this study we investigate, using an atmospheric chemistry model, how this indirect climate effect differs with different amounts of leakages and with where the hydrogen leaks and if this effect changes in the future. The effect is largest for emissions far from areas where hydrogen is removed from the atmosphere by the soil, but these are not relevant locations for a future hydrogen economy.
Alok K. Pandey, David S. Stevenson, Alcide Zhao, Richard J. Pope, Ryan Hossaini, Krishan Kumar, and Martyn P. Chipperfield
Atmos. Chem. Phys., 25, 4785–4802, https://doi.org/10.5194/acp-25-4785-2025, https://doi.org/10.5194/acp-25-4785-2025, 2025
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Nitrogen dioxide is an air pollutant largely controlled by human activity that affects ozone, methane, and aerosols. Satellite instruments can quantify column NO2 and, by carefully matching the time and location of measurements, enable evaluation of model simulations. NO2 over south and east Asia is assessed, showing that the model captures not only many features of the measurements, but also important differences that suggest model deficiencies in representing several aspects of the atmospheric chemistry of NO2.
Mingzhao Liu, Lars Hoffmann, Jens-Uwe Grooß, Zhongyin Cai, Sabine Grießbach, and Yi Heng
Atmos. Chem. Phys., 25, 4403–4418, https://doi.org/10.5194/acp-25-4403-2025, https://doi.org/10.5194/acp-25-4403-2025, 2025
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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.
Yufen Wang, Ke Li, Xi Chen, Zhenjiang Yang, Minglong Tang, Pascoal M. D. Campos, Yang Yang, Xu Yue, and Hong Liao
Atmos. Chem. Phys., 25, 4455–4475, https://doi.org/10.5194/acp-25-4455-2025, https://doi.org/10.5194/acp-25-4455-2025, 2025
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The impacts of biomass burning and anthropogenic emissions on high tropospheric ozone levels are not well studied in southern Africa. We combined model simulations with recent observations at the surface and from space to quantify tropospheric ozone and its 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.
Dominika Pasik, Thomas Golin Almeida, Emelda Ahongshangbam, Siddharth Iyer, and Nanna Myllys
Atmos. Chem. Phys., 25, 4313–4331, https://doi.org/10.5194/acp-25-4313-2025, https://doi.org/10.5194/acp-25-4313-2025, 2025
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We used quantum chemistry methods to investigate the oxidation mechanisms of acyl peroxy radicals (APRs) with various monoterpenes. Our findings reveal unique oxidation pathways for different monoterpenes, leading to either chain-terminating products or highly reactive intermediates that can contribute to particle formation in the atmosphere. This research highlights APRs as potentially significant but underexplored atmospheric oxidants that may influence future approaches to modelling climate.
Jincheol Park, Yunsoo Choi, and Sagun Kayastha
Atmos. Chem. Phys., 25, 4291–4311, https://doi.org/10.5194/acp-25-4291-2025, https://doi.org/10.5194/acp-25-4291-2025, 2025
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We investigated NOx emission contributions to NOy loadings across five regions of East Asia during the 2022 winter–spring transition through chemical transport modeling informed by satellite data. As seasons progress, local contributions within each region to its NOy budget decreased from 32 %–43 % to 23 %–30 %, while transboundary contributions increased from 16 %–33 % to 27 %–37 %, driven by a shift in synoptic settings that allowed pollutants to spread more broadly across the regions.
Qianqian Zhang, K. Folkert Boersma, Chiel van der Laan, Alba Mols, Bin Zhao, Shengyue Li, and Yuepeng Pan
Atmos. Chem. Phys., 25, 3313–3326, https://doi.org/10.5194/acp-25-3313-2025, https://doi.org/10.5194/acp-25-3313-2025, 2025
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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.
Wenbin Kou, Yang Gao, Dan Tong, Xiaojie Guo, Xiadong An, Wenyu Liu, Mengshi Cui, Xiuwen Guo, Shaoqing Zhang, Huiwang Gao, and Lixin Wu
Atmos. Chem. Phys., 25, 3029–3048, https://doi.org/10.5194/acp-25-3029-2025, https://doi.org/10.5194/acp-25-3029-2025, 2025
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Unlike traditional numerical studies, we apply a high-resolution Earth system model, improving simulations of surface ozone and large-scale circulations such as atmospheric blocking. Besides local heat waves, 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 in regional air quality.
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
Atmos. Chem. Phys., 25, 2863–2894, https://doi.org/10.5194/acp-25-2863-2025, https://doi.org/10.5194/acp-25-2863-2025, 2025
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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 optimize these natural emissions over Africa in 2019. Our approach resulted in an increase in natural emissions, supported by independent data indicating that current estimates are underestimated.
Xiaobo Wang, Yuzhong Zhang, Tamás Bozóki, Ruosi Liang, Xinchun Xie, Shutao Zhao, Rui Wang, Yujia Zhao, and Shuai Sun
EGUsphere, https://doi.org/10.5194/egusphere-2025-370, https://doi.org/10.5194/egusphere-2025-370, 2025
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Schumann Resonance observations are used to parameterize lightning NOx emissions for better capturing global lightning trend and variability. Updated simulations reveal insignificant trend but greater variability in lightning NOx emissions, impacting tropospheric NOx, O3 and OH. Lightning generally counteracts non-lightning factors, reducing the inter-annua variability of tropospheric O3 and OH. Variations of global lightning play important role in understanding the atmospheric methane budget.
Jiaqi Shen, Ronald C. Cohen, Glenn M. Wolfe, and Xiaomeng Jin
EGUsphere, https://doi.org/10.5194/egusphere-2025-706, https://doi.org/10.5194/egusphere-2025-706, 2025
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This study shows large chemical and radiative effects of smoke aerosols from fires on near-surface ozone production. Aerosol loading and NOx levels are identified as the primary factors influencing these effects. Furthermore, we show that the surface PM2.5 to NO2 column ratio can be used as an indicator for identifying aerosol-dominated regimes, facilitating the assessments of aerosol impacts on ozone formation through satellite observations.
Shuai Li, Haolin Wang, and Xiao Lu
Atmos. Chem. Phys., 25, 2725–2743, https://doi.org/10.5194/acp-25-2725-2025, https://doi.org/10.5194/acp-25-2725-2025, 2025
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Summertime ozone–temperature sensitivity has decreased by 50 % from 3.0 ppbv per K in 1990 to 1.5 ppb per K in 2021 in the US. GEOS-Chem simulations show that anthropogenic nitrogen oxide emission reduction is the dominant driver of ozone–temperature sensitivity decline by influencing both temperature direct and temperature indirect processes. Reduced ozone–temperature sensitivity has decreased ozone enhancement from low to high temperatures by an average of 6.8 ppbv across the US.
Jinya Yang, Yutong Wang, Lei Zhang, and Yu Zhao
Atmos. Chem. Phys., 25, 2649–2666, https://doi.org/10.5194/acp-25-2649-2025, https://doi.org/10.5194/acp-25-2649-2025, 2025
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We develop a modeling framework to predict future ozone concentrations (till the 2060s) in China following an IPCC scenario. We evaluate 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.
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
Atmos. Chem. Phys., 25, 2243–2268, https://doi.org/10.5194/acp-25-2243-2025, https://doi.org/10.5194/acp-25-2243-2025, 2025
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Five global chemical reanalysis datasets were used to assess the relative impacts of assimilating satellite ozone and its precursor measurements on tropospheric ozone analyses for 2010. The multiple reanalysis system comparison allows an evaluation of the 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 magnitudes among the systems.
Maureen Beaudor, Didier Hauglustaine, Juliette Lathière, Martin Van Damme, Lieven Clarisse, and Nicolas Vuichard
Atmos. Chem. Phys., 25, 2017–2046, https://doi.org/10.5194/acp-25-2017-2025, https://doi.org/10.5194/acp-25-2017-2025, 2025
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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, with significant changes in radiative forcing that can greatly elevate N2O.
Hui Li, Jiaxin Qiu, and Bo Zheng
Atmos. Chem. Phys., 25, 1949–1963, https://doi.org/10.5194/acp-25-1949-2025, https://doi.org/10.5194/acp-25-1949-2025, 2025
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We conduct a sensitivity analysis with 31 tests on various factors including prior emissions, model resolution, satellite constraint, and other system configurations to assess the vulnerability of emission estimates across temporal, sectoral, and regional dimensions. This reveals the robustness of emissions estimated by this air-pollution-satellite-based CO2 emission inversion system, with relative change between tests and base inversion below 4.0 % for national annual NOx and CO2 emissions.
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.
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.
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.
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.
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.
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.
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.
Wanmin Gong, Stephen R. Beagley, Kenjiro Toyota, Henrik Skov, Jesper Heile Christensen, Alexandru Lupu, Diane Pendlebury, Junhua Zhang, Ulas Im, Yugo Kanaya, Alfonso Saiz-Lopez, Roberto Sommariva, Peter Effertz, John W. Halfacre, Nis Jepsen, Rigel Kivi, Theodore K. Koenig, Katrin Müller, Claus Nordstrøm, Irina Petropavlovskikh, Paul B. Shepson, William R. Simpson, Sverre Solberg, Ralf M. Staebler, David W. Tarasick, Roeland Van Malderen, and Mika Vestenius
EGUsphere, https://doi.org/10.5194/egusphere-2024-3750, https://doi.org/10.5194/egusphere-2024-3750, 2025
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This study showed that the springtime O3 depletion plays a critical role in driving the surface O3 seasonal cycle in Central Arctic. The O3 depletion events, while occurring most notably within the lowest few hundred metres above the Arctic Ocean, can induce a 5–7 % of loss in the pan-Arctic tropospheric O3 burden during springtime. The study also found an enhancement in O3 and NOy (mostly PAN) concentrations in the Arctic due to northern boreal wildfires, particularly at altitudes.
Ji Xia, Yi Zhou, Li Fang, Yingfei Qi, Dehao Li, Hong Liao, and Jianbing Jin
EGUsphere, https://doi.org/10.5194/egusphere-2024-3938, https://doi.org/10.5194/egusphere-2024-3938, 2025
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This study established an ammonia emission inventory in South Asia via assimilation-based inversion system. The posterior emissions, calculated by integrating the CEDS inventory and IASI satellite observations, showed significant improvement over the prior. Validation against various measurements all support our posterior emission. It offers valuable insights of ammonia emissions for policymakers and researchers aiming to develop air quality management and mitigation strategies there.
Catalina Poraicu, Jean-François Müller, Trissevgeni Stavrakou, Crist Amelynck, Bert W. D. Verreyken, Niels Schoon, Corinne Vigouroux, Nicolas Kumps, Jérôme Brioude, Pierre Tulet, and Camille Mouchel-Vallon
EGUsphere, https://doi.org/10.5194/egusphere-2024-3555, https://doi.org/10.5194/egusphere-2024-3555, 2025
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We investigated the sources and impacts of nitrogen oxides and organic compounds over a remote tropical island. High-resolution WRF-Chem simulations were evaluated using in situ, FTIR and satellite measurements. This work highlights gaps in current models, like missing sources of key organic compounds and inaccuracies in emission inventories, emphasizing the importance of improving chemical and dynamical processes in atmospheric modelling for budget estimates in tropical regions.
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.
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.
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.
María Cazorla, Melissa Trujillo, Rodrigo Seguel, and Laura Gallardo
EGUsphere, https://doi.org/10.5194/egusphere-2024-3720, https://doi.org/10.5194/egusphere-2024-3720, 2024
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The current climate emergency imposes the need to take actions in cities to curb ozone as a pollutant and a climate forcer. In this work we analyze how reducing the levels of ozone precursor would affect photochemical smog in Quito, Ecuador and Santiago, Chile. Results show that if environmental policy were implemented to reduce only nitrogen oxides, the production of ozone would increase substantially for which more integral solutions are needed.
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.
Xiao Lu, Yiming Liu, Jiayin Su, Xiang Weng, Tabish Ansari, Yuqiang Zhang, Guowen He, Yuqi Zhu, Haolin Wang, Ganquan Zeng, Jingyu Li, Cheng He, Shuai Li, Teerachai Amnuaylojaroen, Tim Butler, Qi Fan, Shaojia Fan, Grant L. Forster, Meng Gao, Jianlin Hu, Yugo Kanaya, Mohd Talib Latif, Keding Lu, Philippe Nédélec, Peer Nowack, Bastien Sauvage, Xiaobin Xu, Lin Zhang, Ke Li, Ja-Ho Koo, and Tatsuya Nagashima
EGUsphere, https://doi.org/10.5194/egusphere-2024-3702, https://doi.org/10.5194/egusphere-2024-3702, 2024
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This study analyzes summertime ozone trends in East and Southeast Asia derived from a comprehensive observational database spanning from 1995 to 2019, incorporating aircraft observations, ozonesonde data, and measurements from 2500 surface sites. Multiple models are applied to attribute to changes in anthropogenic emissions and climate. The results highlight increases in anthropogenic emission are the primary driver of ozone increases both in the free troposphere and at the surface.
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.
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.
Francisco J. Pérez-Invernón, Francisco J. Gordillo-Vázquez, Heidi Huntrieser, Patrick Jöckel, and Eric J. Bucsela
EGUsphere, https://doi.org/10.5194/egusphere-2024-3348, https://doi.org/10.5194/egusphere-2024-3348, 2024
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Lightning plays a significant role in tropospheric chemistry by producing substantial amounts of nitrogen oxides. According to recent estimates, thunderstorms that produce a higher lightning frequency rate also produce less nitrogen oxide per flash. We implemented the dependency of nitrogen oxide production per flash on lightning flash frequency in a chemical atmospheric model.
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.
Nana Wei, Eloise A. Marais, Gongda Lu, Robert G. Ryan, and Bastien Sauvage
EGUsphere, https://doi.org/10.5194/egusphere-2024-3388, https://doi.org/10.5194/egusphere-2024-3388, 2024
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This study uses reactive nitrogen observations from NASA DC-8 research aircraft and The In-service Aircraft for a Global Observing System (IAGOS) campaigns to characterise reactive nitrogen seasonality and composition in the global upper troposphere and to diagnose the greatest knowledge gaps from comparison to a state-of-science model GEOS-Chem that need to be resolved for climate, nitrogen cycle and air pollution assessments.
Barbara Ervens, Andrew Rickard, Bernard Aumont, William P. L. Carter, Max McGillen, Abdelwahid Mellouki, John Orlando, Bénédicte Picquet-Varrault, Paul Seakins, William R. Stockwell, Luc Vereecken, and Timothy J. Wallington
Atmos. Chem. Phys., 24, 13317–13339, https://doi.org/10.5194/acp-24-13317-2024, https://doi.org/10.5194/acp-24-13317-2024, 2024
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Chemical mechanisms describe the chemical processes in atmospheric models that are used to describe the changes in the atmospheric composition. Therefore, accurate chemical mechanisms are necessary to predict the evolution of air pollution and climate change. The article describes all steps that are needed to build chemical mechanisms and discusses the advances and needs of experimental and theoretical research activities needed to build reliable chemical mechanisms.
Audrey Fortems-Cheiney, Grégoire Broquet, Robin Plauchu, Elise Potier, Antoine Berchet, Isabelle Pison, Adrien Martinez, Rimal Abeed, Gaelle Dufour, Adriana Coman, Dilek Savas, Guillaume Siour, Henk Eskes, Hugo A. C. Denier van der Gon, and Stijn N. C. Dellaert
EGUsphere, https://doi.org/10.5194/egusphere-2024-3679, https://doi.org/10.5194/egusphere-2024-3679, 2024
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This study assesses the potential of the OMI and TROPOMI satellite observations to inform about the evolution of NOx anthropogenic emissions between year 2005 and year 2019 at the regional to national scales in Europe. Both the OMI and TROPOMI inversions show decreases in European NOx anthropogenic emission budgets between 2005 and 2019, but with different magnitudes.
Yawen Kong, Bo Zheng, and Yuxi Liu
EGUsphere, https://doi.org/10.5194/egusphere-2024-2996, https://doi.org/10.5194/egusphere-2024-2996, 2024
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Current high-resolution satellite remote sensing technologies provide a unique opportunity to derive timely, high-resolution emission data. We developed an emission inversion system to assimilate satellite NO2 data to obtain daily, kilometer-scale NOx emission inventories. Our results enhance inventory accuracy, allowing us to capture the effects of pollution control policies on daily emissions (e.g., during COVID-19 lockdown) and improve fine-scale air quality modeling.
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.
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.
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.
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.
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.
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Anderson, D. C., Duncan, B. N., Fiore, A. M., Baublitz, C. B., Follette-Cook, M. B., Nicely, J. M., and Wolfe, G. M.: Spatial and temporal variability in the hydroxyl (OH) radical: understanding the role of large-scale climate features and their influence on OH through its dynamical and photochemical drivers, Atmos. Chem. Phys., 21, 6481–6508, https://doi.org/10.5194/acp-21-6481-2021, 2021. a
Bian, H. and Prather, M. J.: Fast-J2: Accurate Simulation of Stratospheric Photolysis in Global Chemical Models, J. Atmos. Chem., 41, 281–296, https://doi.org/10.1023/a:1014980619462, 2002. a
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Short summary
The hydroxyl radical (OH) is an atmospheric
detergent, removing air pollutants and greenhouse gases like methane from the atmosphere. Thus, understanding how it is changing and responding to its various drivers is important for air quality and climate. We found that OH has increased by about 5 % globally from 1980 to 2014 in our model, mostly driven by increasing nitrogen oxide (NOx) emissions. This suggests potential climate tradeoffs from air quality policies solely targeting NOx emissions.
The hydroxyl radical (OH) is an atmospheric
detergent, removing air pollutants and greenhouse...
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