Articles | Volume 16, issue 14
https://doi.org/10.5194/acp-16-9129-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/acp-16-9129-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
25 Jul 2016
Research article |
| 25 Jul 2016
Upper-tropospheric CO and O3 budget during the Asian summer monsoon
Brice Barret
CORRESPONDING AUTHOR
Laboratoire d'Aérologie, Université de Toulouse, CNRS, UPS, Toulouse, France
Bastien Sauvage
Laboratoire d'Aérologie, Université de Toulouse, CNRS, UPS, Toulouse, France
Yasmine Bennouna
Laboratoire d'Aérologie, Université de Toulouse, CNRS, UPS, Toulouse, France
Eric Le Flochmoen
Laboratoire d'Aérologie, Université de Toulouse, CNRS, UPS, Toulouse, France
Related authors
Antonio Donateo, Gianluca Pappaccogli, Federico Scoto, Maurizio Busetto, Francesca Lucia Lovisco, Natalie Brett, Douglas Keller, Brice Barret, Elsa Dieudonné, Roman Pohorsky, Andrea Baccarini, Slimane Bekki, Jean-Christophe Raut, Julia Schmale, Kathy S. Law, Steve R. Arnold, Gilberto Javier Fochesatto, William R. Simpson, and Stefano Decesari
EGUsphere, https://doi.org/10.5194/egusphere-2025-1366, https://doi.org/10.5194/egusphere-2025-1366, 2025
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
A study in Fairbanks, Alaska, measured winter aerosol fluxes on snow. Both emission and deposition occurred, with larger particles settling faster. Weather influenced dispersion and deposition, while wind-driven turbulence enhanced deposition despite stable conditions. Results show aerosol accumulation in snow impacts pollution and snowmelt. Findings help improve aerosol models and pollution studies in cold cities.
Roman Pohorsky, Andrea Baccarini, Natalie Brett, Brice Barret, Slimane Bekki, Gianluca Pappaccogli, Elsa Dieudonné, Brice Temime-Roussel, Barbara D'Anna, Meeta Cesler-Maloney, Antonio Donateo, Stefano Decesari, Kathy S. Law, William R. Simpson, Javier Fochesatto, Steve R. Arnold, and Julia Schmale
Atmos. Chem. Phys., 25, 3687–3715, https://doi.org/10.5194/acp-25-3687-2025, https://doi.org/10.5194/acp-25-3687-2025, 2025
Short summary
Short summary
This study presents an analysis of vertical measurements of pollution in an Alaskan city during winter. It investigates the relationship between the atmospheric structure and the layering of aerosols and trace gases. Results indicate an overall very shallow surface mixing layer. The height of this layer is strongly influenced by a local shallow wind. The study also provides information on the pollution chemical composition at different altitudes, including pollution signatures from power plants.
Brice Barret, Patrice Medina, Natalie Brett, Roman Pohorsky, Kathy S. Law, Slimane Bekki, Gilberto J. Fochesatto, Julia Schmale, Steve R. Arnold, Andrea Baccarini, Maurizio Busetto, Meeta Cesler-Maloney, Barbara D'Anna, Stefano Decesari, Jingqiu Mao, Gianluca Pappaccogli, Joel Savarino, Federico Scoto, and William R. Simpson
Atmos. Meas. Tech., 18, 1163–1184, https://doi.org/10.5194/amt-18-1163-2025, https://doi.org/10.5194/amt-18-1163-2025, 2025
Short summary
Short summary
The Fairbanks area experiences severe pollution episodes in winter because of enhanced emissions of pollutants trapped near the surface by strong temperature inversions. Low-cost sensors were deployed on board a car and a tethered balloon to measure the concentrations of gaseous pollutants (CO, O3, and NOx) in Fairbanks during winter 2022. Data calibration with reference measurements and machine learning methods enabled us to document pollution at the surface and power plant plumes aloft.
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
Short summary
Short summary
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.
Brice Barret, Pierre Loicq, Eric Le Flochmoën, Yasmine Bennouna, Juliette Hadji-Lazaro, Daniel Hurtmans, and Bastien Sauvage
Atmos. Meas. Tech., 18, 129–149, https://doi.org/10.5194/amt-18-129-2025, https://doi.org/10.5194/amt-18-129-2025, 2025
Short summary
Short summary
Profiles of carbon monoxide (CO) retrieved from the Infrared Atmospheric Sounding Interferometer (IASI) with the SOftware for a Fast Retrieval of IASI Data (SOFRID) and Fast Optimal Retrievals on Layers for IASI (FORLI) are validated with 8500 observations at 33 airports from the In-service Aircraft for a Global Observing System (IAGOS) for 2008–2019. IASI retrievals underestimate CO, with stronger bias in the middle to upper troposphere for SOFRID and in the lower troposphere for FORLI.
Amna Ijaz, Brice Temime-Roussel, Benjamin Chazeau, Sarah Albertin, Stephen R. Arnold, Brice Barrett, Slimane Bekki, Natalie Brett, Meeta Cesler-Maloney, Elsa Dieudonne, Kayane K. Dingilian, Javier G. Fochesatto, Jingqiu Mao, Allison Moon, Joel Savarino, William Simpson, Rodney J. Weber, Kathy S. Law, and Barbara D'Anna
EGUsphere, https://doi.org/10.5194/egusphere-2024-3789, https://doi.org/10.5194/egusphere-2024-3789, 2024
Short summary
Short summary
Fairbanks is among the most polluted cities with the highest particulate matter (PM) levels in the US during winters. Highly time-resolved measurements of the sub-micron PM elucidated residential heating with wood and oil and hydrocarbon-like organics from traffic, as well as sulphur-containing organic aerosol, to be the key pollution sources. Remarkable differences existed between complementary instruments, warranting the deployment of multiple tools at sites with wide-ranging influences.
Suvarna Fadnavis, Yasin Elshorbany, Jerald Ziemke, Brice Barret, Alexandru Rap, P. R. Satheesh Chandran, Richard Pope, Vijay Sagar, Domenico Taraborrelli, Eric Le Flochmoen, Juan Cuesta, Catherine Wespes, Folkert Boersma, Isolde Glissenaar, Isabelle De Smedt, Michel Van Roozendael, Hervé Petetin, and Isidora Anglou
EGUsphere, https://doi.org/10.5194/egusphere-2024-3050, https://doi.org/10.5194/egusphere-2024-3050, 2024
Short summary
Short summary
Satellites and model simulations show enhancement in tropospheric ozone, which is highly impacted by human-produced Nitrous oxides compared to volatile organic compounds. The increased amount of ozone enhances ozone radiative forcing. The ozone enhancement and associated radiative forcing are highest over South and East Asia. The emissions of Nitrous oxides show a higher influence in shifting ozone photochemical regimes than volatile organic compounds.
Richard J. Pope, Fiona M. O'Connor, Mohit Dalvi, Brian J. Kerridge, Richard Siddans, Barry G. Latter, Brice Barret, Eric Le Flochmoen, Anne Boynard, Martyn P. Chipperfield, Wuhu Feng, Matilda A. Pimlott, Sandip S. Dhomse, Christian Retscher, Catherine Wespes, and Richard Rigby
Atmos. Chem. Phys., 24, 9177–9195, https://doi.org/10.5194/acp-24-9177-2024, https://doi.org/10.5194/acp-24-9177-2024, 2024
Short summary
Short summary
Ozone is a potent air pollutant in the lower troposphere, with adverse impacts on human health. Satellite records of tropospheric ozone currently show large-scale inconsistencies in long-term trends. Our detailed study of the potential factors (e.g. satellite errors, where the satellite can observe ozone) potentially driving these inconsistencies found that, in North America, Europe, and East Asia, the underlying trends are typically small with large uncertainties.
Richard J. Pope, Alexandru Rap, Matilda A. Pimlott, Brice Barret, Eric Le Flochmoen, Brian J. Kerridge, Richard Siddans, Barry G. Latter, Lucy J. Ventress, Anne Boynard, Christian Retscher, Wuhu Feng, Richard Rigby, Sandip S. Dhomse, Catherine Wespes, and Martyn P. Chipperfield
Atmos. Chem. Phys., 24, 3613–3626, https://doi.org/10.5194/acp-24-3613-2024, https://doi.org/10.5194/acp-24-3613-2024, 2024
Short summary
Short summary
Tropospheric ozone is an important short-lived climate forcer which influences the incoming solar short-wave radiation and the outgoing long-wave radiation in the atmosphere (8–15 km) where the balance between the two yields a net positive (i.e. warming) effect at the surface. Overall, we find that the tropospheric ozone radiative effect ranges between 1.21 and 1.26 W m−2 with a negligible trend (2008–2017), suggesting that tropospheric ozone influences on climate have remained stable with time.
Maria Tsivlidou, Bastien Sauvage, Yasmine Bennouna, Romain Blot, Damien Boulanger, Hannah Clark, Eric Le Flochmoën, Philippe Nédélec, Valérie Thouret, Pawel Wolff, and Brice Barret
Atmos. Chem. Phys., 23, 14039–14063, https://doi.org/10.5194/acp-23-14039-2023, https://doi.org/10.5194/acp-23-14039-2023, 2023
Short summary
Short summary
The tropics are a region where the ozone increase has been most apparent since 1980 and where observations are sparse. Using aircraft, satellite, and model data, we document the characteristics of tropospheric ozone and CO over the whole tropics for the last 2 decades. We explore the origin of the observed CO anomalies and investigate transport processes driving the tropical CO and O3 distribution. Our study highlights the importance of anthropogenic emissions, mostly over the northern tropics.
Hannah Clark, Yasmine Bennouna, Maria Tsivlidou, Pawel Wolff, Bastien Sauvage, Brice Barret, Eric Le Flochmoën, Romain Blot, Damien Boulanger, Jean-Marc Cousin, Philippe Nédélec, Andreas Petzold, and Valérie Thouret
Atmos. Chem. Phys., 21, 16237–16256, https://doi.org/10.5194/acp-21-16237-2021, https://doi.org/10.5194/acp-21-16237-2021, 2021
Short summary
Short summary
We examined 27 years of IAGOS (In-service Aircraft for a Global Observing System) profiles at Frankfurt to see if there were unusual features during the spring of 2020 related to COVID-19 lockdowns in Europe. Increased ozone near the surface was partly linked to the reduction in emissions. Carbon monoxide decreased near the surface, but the impact of the lockdowns was offset by polluted air masses from elsewhere. There were small reductions in ozone and carbon monoxide in the free troposphere.
Victor Lannuque, Bastien Sauvage, Brice Barret, Hannah Clark, Gilles Athier, Damien Boulanger, Jean-Pierre Cammas, Jean-Marc Cousin, Alain Fontaine, Eric Le Flochmoën, Philippe Nédélec, Hervé Petetin, Isabelle Pfaffenzeller, Susanne Rohs, Herman G. J. Smit, Pawel Wolff, and Valérie Thouret
Atmos. Chem. Phys., 21, 14535–14555, https://doi.org/10.5194/acp-21-14535-2021, https://doi.org/10.5194/acp-21-14535-2021, 2021
Short summary
Short summary
The African intertropical troposphere is one of the world areas where the increase in ozone mixing ratio has been most pronounced since 1980 and where high carbon monoxide mixing ratios are found in altitude. In this article, IAGOS aircraft measurements, IASI satellite instrument observations, and SOFT-IO model products are used to explore the seasonal distribution variations and the origin of ozone and carbon monoxide over the African upper troposphere.
Keun-Ok Lee, Brice Barret, Eric L. Flochmoën, Pierre Tulet, Silvia Bucci, Marc von Hobe, Corinna Kloss, Bernard Legras, Maud Leriche, Bastien Sauvage, Fabrizio Ravegnani, and Alexey Ulanovsky
Atmos. Chem. Phys., 21, 3255–3274, https://doi.org/10.5194/acp-21-3255-2021, https://doi.org/10.5194/acp-21-3255-2021, 2021
Short summary
Short summary
This paper focuses on the emission sources and pathways of pollution from the boundary layer to the Asian monsoon anticyclone (AMA) during the StratoClim aircraft campaign period. Simulations with the Meso-NH cloud-chemistry model at a horizontal resolution of 15 km are performed over the Asian region to characterize the impact of monsoon deep convection on the composition of AMA and on the formation of the Asian tropopause aerosol layer during the StratoClim campaign.
Brice Barret, Emanuele Emili, and Eric Le Flochmoen
Atmos. Meas. Tech., 13, 5237–5257, https://doi.org/10.5194/amt-13-5237-2020, https://doi.org/10.5194/amt-13-5237-2020, 2020
Short summary
Short summary
The IASI satellite sensor is used to document the variability and evolution of tropospheric ozone (O3). IASI O3 retrievals generally use a single a priori profile which can be responsible for biases and too-low variability. We have therefore implemented a dynamical a priori profile based on pixel location, month and tropopause height. Comparison with 10 years of global ozonesonde profiles shows large improvements in the retrieved tropospheric O3, with biases corrected and enhanced variabilities.
Corinna Kloss, Gwenaël Berthet, Pasquale Sellitto, Felix Ploeger, Silvia Bucci, Sergey Khaykin, Fabrice Jégou, Ghassan Taha, Larry W. Thomason, Brice Barret, Eric Le Flochmoen, Marc von Hobe, Adriana Bossolasco, Nelson Bègue, and Bernard Legras
Atmos. Chem. Phys., 19, 13547–13567, https://doi.org/10.5194/acp-19-13547-2019, https://doi.org/10.5194/acp-19-13547-2019, 2019
Short summary
Short summary
With satellite measurements and transport models, we show that a plume resulting from strong Canadian fires in July/August 2017 was not only distributed throughout the northern/higher latitudes, but also reached the faraway tropics, aided by the circulation of Asian monsoon anticyclone. The regional climate impact in the wider Asian monsoon area in September exceeds the impact of the Asian tropopause aerosol layer by a factor of ~ 3 and compares to that of an advected moderate volcanic eruption.
Emanuele Emili, Brice Barret, Eric Le Flochmoën, and Daniel Cariolle
Atmos. Meas. Tech., 12, 3963–3984, https://doi.org/10.5194/amt-12-3963-2019, https://doi.org/10.5194/amt-12-3963-2019, 2019
Short summary
Short summary
We examine the differences between assimilating ozone profiles retrieved from IASI or the corresponding infrared spectra in a chemical transport model. This allows the impact of the retrieval's prior information on ozone reanalyses to be quantified. We found that significant differences can arise between the two approaches, depending on the latitude. An improved O3 variability is obtained assimilating IASI radiances directly. The implications for coupled Earth system models are discussed.
Hélène Peiro, Emanuele Emili, Daniel Cariolle, Brice Barret, and Eric Le Flochmoën
Atmos. Chem. Phys., 18, 6939–6958, https://doi.org/10.5194/acp-18-6939-2018, https://doi.org/10.5194/acp-18-6939-2018, 2018
Short summary
Short summary
Tropospheric ozone (O3) is the third most important greenhouse gas. Several sensors on satellites measure O3 concentration like the infrared sounding IASI of MetOp satellites with a spatiotemporal coverage never reached so far. The assimilation of tropospheric IASI data within the chemistry transport model MOCAGE gives a good representation of O3 variability over the tropics linked with ENSO and the Walker circulation. IASI assimilation can contribute to the long-term monitoring of O3.
François Gheusi, Pierre Durand, Nicolas Verdier, François Dulac, Jean-Luc Attié, Philippe Commun, Brice Barret, Claude Basdevant, Antoine Clenet, Solène Derrien, Alexis Doerenbecher, Laaziz El Amraoui, Alain Fontaine, Emeric Hache, Corinne Jambert, Elodie Jaumouillé, Yves Meyerfeld, Laurent Roblou, and Flore Tocquer
Atmos. Meas. Tech., 9, 5811–5832, https://doi.org/10.5194/amt-9-5811-2016, https://doi.org/10.5194/amt-9-5811-2016, 2016
Short summary
Short summary
Boundary-layer pressurised balloons allow for horizontal multi-day flights in the lower atmosphere, carrying light scientific payloads. Ozonesondes, usually used for balloon soundings have too short a lifetime for such flights. An adaptation is proposed, whereby conventional sondes are operated with short measurement phases alternating with longer periods of dormancy. The sondes were operated over the western Mediterranean, offering an original perspective on tropospheric ozone.
Sarah Safieddine, Anne Boynard, Nan Hao, Fuxiang Huang, Lili Wang, Dongsheng Ji, Brice Barret, Sachin D. Ghude, Pierre-François Coheur, Daniel Hurtmans, and Cathy Clerbaux
Atmos. Chem. Phys., 16, 10489–10500, https://doi.org/10.5194/acp-16-10489-2016, https://doi.org/10.5194/acp-16-10489-2016, 2016
Short summary
Short summary
The Asian Summer Monsoon has implication on the weather and climate system as well as pollutants concentration over the monsoon regions leading to effects on the global air quality. Our results, combining satellite, aircraft and ground station data, show that tropospheric ozone, decrease during the period May–August over East and South Asia due to the Monsoon. The magnitude of this drop depends largely on meteorology and geographic location.
C. Crevoisier, C. Clerbaux, V. Guidard, T. Phulpin, R. Armante, B. Barret, C. Camy-Peyret, J.-P. Chaboureau, P.-F. Coheur, L. Crépeau, G. Dufour, L. Labonnote, L. Lavanant, J. Hadji-Lazaro, H. Herbin, N. Jacquinet-Husson, S. Payan, E. Péquignot, C. Pierangelo, P. Sellitto, and C. Stubenrauch
Atmos. Meas. Tech., 7, 4367–4385, https://doi.org/10.5194/amt-7-4367-2014, https://doi.org/10.5194/amt-7-4367-2014, 2014
E. Emili, B. Barret, S. Massart, E. Le Flochmoen, A. Piacentini, L. El Amraoui, O. Pannekoucke, and D. Cariolle
Atmos. Chem. Phys., 14, 177–198, https://doi.org/10.5194/acp-14-177-2014, https://doi.org/10.5194/acp-14-177-2014, 2014
Antonio Donateo, Gianluca Pappaccogli, Federico Scoto, Maurizio Busetto, Francesca Lucia Lovisco, Natalie Brett, Douglas Keller, Brice Barret, Elsa Dieudonné, Roman Pohorsky, Andrea Baccarini, Slimane Bekki, Jean-Christophe Raut, Julia Schmale, Kathy S. Law, Steve R. Arnold, Gilberto Javier Fochesatto, William R. Simpson, and Stefano Decesari
EGUsphere, https://doi.org/10.5194/egusphere-2025-1366, https://doi.org/10.5194/egusphere-2025-1366, 2025
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
A study in Fairbanks, Alaska, measured winter aerosol fluxes on snow. Both emission and deposition occurred, with larger particles settling faster. Weather influenced dispersion and deposition, while wind-driven turbulence enhanced deposition despite stable conditions. Results show aerosol accumulation in snow impacts pollution and snowmelt. Findings help improve aerosol models and pollution studies in cold cities.
Roman Pohorsky, Andrea Baccarini, Natalie Brett, Brice Barret, Slimane Bekki, Gianluca Pappaccogli, Elsa Dieudonné, Brice Temime-Roussel, Barbara D'Anna, Meeta Cesler-Maloney, Antonio Donateo, Stefano Decesari, Kathy S. Law, William R. Simpson, Javier Fochesatto, Steve R. Arnold, and Julia Schmale
Atmos. Chem. Phys., 25, 3687–3715, https://doi.org/10.5194/acp-25-3687-2025, https://doi.org/10.5194/acp-25-3687-2025, 2025
Short summary
Short summary
This study presents an analysis of vertical measurements of pollution in an Alaskan city during winter. It investigates the relationship between the atmospheric structure and the layering of aerosols and trace gases. Results indicate an overall very shallow surface mixing layer. The height of this layer is strongly influenced by a local shallow wind. The study also provides information on the pollution chemical composition at different altitudes, including pollution signatures from power plants.
Brice Barret, Patrice Medina, Natalie Brett, Roman Pohorsky, Kathy S. Law, Slimane Bekki, Gilberto J. Fochesatto, Julia Schmale, Steve R. Arnold, Andrea Baccarini, Maurizio Busetto, Meeta Cesler-Maloney, Barbara D'Anna, Stefano Decesari, Jingqiu Mao, Gianluca Pappaccogli, Joel Savarino, Federico Scoto, and William R. Simpson
Atmos. Meas. Tech., 18, 1163–1184, https://doi.org/10.5194/amt-18-1163-2025, https://doi.org/10.5194/amt-18-1163-2025, 2025
Short summary
Short summary
The Fairbanks area experiences severe pollution episodes in winter because of enhanced emissions of pollutants trapped near the surface by strong temperature inversions. Low-cost sensors were deployed on board a car and a tethered balloon to measure the concentrations of gaseous pollutants (CO, O3, and NOx) in Fairbanks during winter 2022. Data calibration with reference measurements and machine learning methods enabled us to document pollution at the surface and power plant plumes aloft.
Anne M. Thompson, Ryan M. Stauffer, Debra E. Kollonige, Jerald R. Ziemke, Maria Cazorla, Pawel Wolff, and Bastien Sauvage
EGUsphere, https://doi.org/10.5194/egusphere-2024-3761, https://doi.org/10.5194/egusphere-2024-3761, 2025
Short summary
Short summary
This paper uses tropical ozone profiles from balloon borne instruments and aircraft to show that ozone in the free troposphere is not growing fast except over equatorial SE Asia.
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
Short summary
Short summary
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.
Pasquale Sellitto, Audrey Gaudel, and Bastien Sauvage
EGUsphere, https://doi.org/10.5194/egusphere-2024-3748, https://doi.org/10.5194/egusphere-2024-3748, 2025
Short summary
Short summary
Tropospheric ozone is a potent greenhouse gas; its anthropogenic levels rise contributes to climate change. We evaluate tropospheric ozone trends and climate impacts with aircraft data and a radiative model, comparing the baseline period (1994–2004) to 2011–2016 and 2019. Tropospheric ozone levels increased significantly but with a smaller trend in 2019 than in 2011–2016. However, ozone radiative forcing did not decrease between these periods because of different vertical distribution evolutions
Eric Martial Yao, Fabien Solmon, Marcellin Adon, Claire Delon, Corinne Galy-Lacaux, Graziano Giuliani, Bastien Sauvage, and Véronique Yoboue
EGUsphere, https://doi.org/10.5194/egusphere-2024-3179, https://doi.org/10.5194/egusphere-2024-3179, 2025
Short summary
Short summary
As climate change and human activities intensify in Africa, understanding how air pollution, climate, and natural cycles interact is crucial. This study explores how nitrogen oxide emissions from African soils, especially in dry regions, contribute to atmospheric pollution. By using a climate-chemistry model, we show that considering these emissions improves predictions of nitrogen dioxide, nitric acid and ozone, although some discrepancies remain compared to observations.
Brice Barret, Pierre Loicq, Eric Le Flochmoën, Yasmine Bennouna, Juliette Hadji-Lazaro, Daniel Hurtmans, and Bastien Sauvage
Atmos. Meas. Tech., 18, 129–149, https://doi.org/10.5194/amt-18-129-2025, https://doi.org/10.5194/amt-18-129-2025, 2025
Short summary
Short summary
Profiles of carbon monoxide (CO) retrieved from the Infrared Atmospheric Sounding Interferometer (IASI) with the SOftware for a Fast Retrieval of IASI Data (SOFRID) and Fast Optimal Retrievals on Layers for IASI (FORLI) are validated with 8500 observations at 33 airports from the In-service Aircraft for a Global Observing System (IAGOS) for 2008–2019. IASI retrievals underestimate CO, with stronger bias in the middle to upper troposphere for SOFRID and in the lower troposphere for FORLI.
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
Short summary
Short summary
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
Short summary
Short summary
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.
Amna Ijaz, Brice Temime-Roussel, Benjamin Chazeau, Sarah Albertin, Stephen R. Arnold, Brice Barrett, Slimane Bekki, Natalie Brett, Meeta Cesler-Maloney, Elsa Dieudonne, Kayane K. Dingilian, Javier G. Fochesatto, Jingqiu Mao, Allison Moon, Joel Savarino, William Simpson, Rodney J. Weber, Kathy S. Law, and Barbara D'Anna
EGUsphere, https://doi.org/10.5194/egusphere-2024-3789, https://doi.org/10.5194/egusphere-2024-3789, 2024
Short summary
Short summary
Fairbanks is among the most polluted cities with the highest particulate matter (PM) levels in the US during winters. Highly time-resolved measurements of the sub-micron PM elucidated residential heating with wood and oil and hydrocarbon-like organics from traffic, as well as sulphur-containing organic aerosol, to be the key pollution sources. Remarkable differences existed between complementary instruments, warranting the deployment of multiple tools at sites with wide-ranging influences.
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
Short summary
Short summary
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.
Suvarna Fadnavis, Yasin Elshorbany, Jerald Ziemke, Brice Barret, Alexandru Rap, P. R. Satheesh Chandran, Richard Pope, Vijay Sagar, Domenico Taraborrelli, Eric Le Flochmoen, Juan Cuesta, Catherine Wespes, Folkert Boersma, Isolde Glissenaar, Isabelle De Smedt, Michel Van Roozendael, Hervé Petetin, and Isidora Anglou
EGUsphere, https://doi.org/10.5194/egusphere-2024-3050, https://doi.org/10.5194/egusphere-2024-3050, 2024
Short summary
Short summary
Satellites and model simulations show enhancement in tropospheric ozone, which is highly impacted by human-produced Nitrous oxides compared to volatile organic compounds. The increased amount of ozone enhances ozone radiative forcing. The ozone enhancement and associated radiative forcing are highest over South and East Asia. The emissions of Nitrous oxides show a higher influence in shifting ozone photochemical regimes than volatile organic compounds.
Audrey Gaudel, Ilann Bourgeois, Meng Li, Kai-Lan Chang, Jerald Ziemke, Bastien Sauvage, Ryan M. Stauffer, Anne M. Thompson, Debra E. Kollonige, Nadia Smith, Daan Hubert, Arno Keppens, Juan Cuesta, Klaus-Peter Heue, Pepijn Veefkind, Kenneth Aikin, Jeff Peischl, Chelsea R. Thompson, Thomas B. Ryerson, Gregory J. Frost, Brian C. McDonald, and Owen R. Cooper
Atmos. Chem. Phys., 24, 9975–10000, https://doi.org/10.5194/acp-24-9975-2024, https://doi.org/10.5194/acp-24-9975-2024, 2024
Short summary
Short summary
The study examines tropical tropospheric ozone changes. In situ data from 1994–2019 display increased ozone, notably over India, Southeast Asia, and Malaysia and Indonesia. Sparse in situ data limit trend detection for the 15-year period. In situ and satellite data, with limited sampling, struggle to consistently detect trends. Continuous observations are vital over the tropical Pacific Ocean, Indian Ocean, western Africa, and South Asia for accurate ozone trend estimation in these regions.
Henk Eskes, Athanasios Tsikerdekis, Melanie Ades, Mihai Alexe, Anna Carlin Benedictow, Yasmine Bennouna, Lewis Blake, Idir Bouarar, Simon Chabrillat, Richard Engelen, Quentin Errera, Johannes Flemming, Sebastien Garrigues, Jan Griesfeller, Vincent Huijnen, Luka Ilić, Antje Inness, John Kapsomenakis, Zak Kipling, Bavo Langerock, Augustin Mortier, Mark Parrington, Isabelle Pison, Mikko Pitkänen, Samuel Remy, Andreas Richter, Anja Schoenhardt, Michael Schulz, Valerie Thouret, Thorsten Warneke, Christos Zerefos, and Vincent-Henri Peuch
Atmos. Chem. Phys., 24, 9475–9514, https://doi.org/10.5194/acp-24-9475-2024, https://doi.org/10.5194/acp-24-9475-2024, 2024
Short summary
Short summary
The Copernicus Atmosphere Monitoring Service (CAMS) provides global analyses and forecasts of aerosols and trace gases in the atmosphere. On 27 June 2023 a major upgrade, Cy48R1, became operational. Comparisons with in situ, surface remote sensing, aircraft, and balloon and satellite observations show that the new CAMS system is a significant improvement. The results quantify the skill of CAMS to forecast impactful events, such as wildfires, dust storms and air pollution peaks.
Richard J. Pope, Fiona M. O'Connor, Mohit Dalvi, Brian J. Kerridge, Richard Siddans, Barry G. Latter, Brice Barret, Eric Le Flochmoen, Anne Boynard, Martyn P. Chipperfield, Wuhu Feng, Matilda A. Pimlott, Sandip S. Dhomse, Christian Retscher, Catherine Wespes, and Richard Rigby
Atmos. Chem. Phys., 24, 9177–9195, https://doi.org/10.5194/acp-24-9177-2024, https://doi.org/10.5194/acp-24-9177-2024, 2024
Short summary
Short summary
Ozone is a potent air pollutant in the lower troposphere, with adverse impacts on human health. Satellite records of tropospheric ozone currently show large-scale inconsistencies in long-term trends. Our detailed study of the potential factors (e.g. satellite errors, where the satellite can observe ozone) potentially driving these inconsistencies found that, in North America, Europe, and East Asia, the underlying trends are typically small with large uncertainties.
Richard J. Pope, Alexandru Rap, Matilda A. Pimlott, Brice Barret, Eric Le Flochmoen, Brian J. Kerridge, Richard Siddans, Barry G. Latter, Lucy J. Ventress, Anne Boynard, Christian Retscher, Wuhu Feng, Richard Rigby, Sandip S. Dhomse, Catherine Wespes, and Martyn P. Chipperfield
Atmos. Chem. Phys., 24, 3613–3626, https://doi.org/10.5194/acp-24-3613-2024, https://doi.org/10.5194/acp-24-3613-2024, 2024
Short summary
Short summary
Tropospheric ozone is an important short-lived climate forcer which influences the incoming solar short-wave radiation and the outgoing long-wave radiation in the atmosphere (8–15 km) where the balance between the two yields a net positive (i.e. warming) effect at the surface. Overall, we find that the tropospheric ozone radiative effect ranges between 1.21 and 1.26 W m−2 with a negligible trend (2008–2017), suggesting that tropospheric ozone influences on climate have remained stable with time.
Yann Cohen, Didier Hauglustaine, Bastien Sauvage, Susanne Rohs, Patrick Konjari, Ulrich Bundke, Andreas Petzold, Valérie Thouret, Andreas Zahn, and Helmut Ziereis
Atmos. Chem. Phys., 23, 14973–15009, https://doi.org/10.5194/acp-23-14973-2023, https://doi.org/10.5194/acp-23-14973-2023, 2023
Short summary
Short summary
The upper troposphere–lower stratosphere (UTLS) is a key region regarding the lower atmospheric composition. This study consists of a comprehensive evaluation of an up-to-date chemistry–climate model in this layer, using regular in situ measurements based on passenger aircraft. For this purpose, a specific software (Interpol-IAGOS) has been updated and made publicly available. The model reproduces the carbon monoxide peaks due to biomass burning over the continental tropics particularly well.
Maria Tsivlidou, Bastien Sauvage, Yasmine Bennouna, Romain Blot, Damien Boulanger, Hannah Clark, Eric Le Flochmoën, Philippe Nédélec, Valérie Thouret, Pawel Wolff, and Brice Barret
Atmos. Chem. Phys., 23, 14039–14063, https://doi.org/10.5194/acp-23-14039-2023, https://doi.org/10.5194/acp-23-14039-2023, 2023
Short summary
Short summary
The tropics are a region where the ozone increase has been most apparent since 1980 and where observations are sparse. Using aircraft, satellite, and model data, we document the characteristics of tropospheric ozone and CO over the whole tropics for the last 2 decades. We explore the origin of the observed CO anomalies and investigate transport processes driving the tropical CO and O3 distribution. Our study highlights the importance of anthropogenic emissions, mostly over the northern tropics.
Haolin Wang, Xiao Lu, Daniel J. Jacob, Owen R. Cooper, Kai-Lan Chang, Ke Li, Meng Gao, Yiming Liu, Bosi Sheng, Kai Wu, Tongwen Wu, Jie Zhang, Bastien Sauvage, Philippe Nédélec, Romain Blot, and Shaojia Fan
Atmos. Chem. Phys., 22, 13753–13782, https://doi.org/10.5194/acp-22-13753-2022, https://doi.org/10.5194/acp-22-13753-2022, 2022
Short summary
Short summary
We report significant global tropospheric ozone increases in 1995–2017 based on extensive aircraft and ozonesonde observations. Using GEOS-Chem (Goddard Earth Observing System chemistry model) multi-decadal global simulations, we find that changes in global anthropogenic emissions, in particular the rapid increases in aircraft emissions, contribute significantly to the increases in tropospheric ozone and resulting radiative impact.
Graciela B. Raga, Darrel Baumgardner, Blanca Rios, Yanet Díaz-Esteban, Alejandro Jaramillo, Martin Gallagher, Bastien Sauvage, Pawel Wolff, and Gary Lloyd
Atmos. Chem. Phys., 22, 2269–2292, https://doi.org/10.5194/acp-22-2269-2022, https://doi.org/10.5194/acp-22-2269-2022, 2022
Short summary
Short summary
The In-Service Aircraft for a Global Observing System (IAGOS) is a small fleet of commercial aircraft that carry a suite of meteorological, gas, aerosol, and cloud sensors and have been measuring worldwide for almost 9 years, since late 2011. Extreme ice events (EIEs) have been identified from the IAGOS cloud measurements and linked to surface emissions for biomass and fossil fuel consumption. The results reported here are highly relevant for climate change and flight operations forecasting.
Hannah Clark, Yasmine Bennouna, Maria Tsivlidou, Pawel Wolff, Bastien Sauvage, Brice Barret, Eric Le Flochmoën, Romain Blot, Damien Boulanger, Jean-Marc Cousin, Philippe Nédélec, Andreas Petzold, and Valérie Thouret
Atmos. Chem. Phys., 21, 16237–16256, https://doi.org/10.5194/acp-21-16237-2021, https://doi.org/10.5194/acp-21-16237-2021, 2021
Short summary
Short summary
We examined 27 years of IAGOS (In-service Aircraft for a Global Observing System) profiles at Frankfurt to see if there were unusual features during the spring of 2020 related to COVID-19 lockdowns in Europe. Increased ozone near the surface was partly linked to the reduction in emissions. Carbon monoxide decreased near the surface, but the impact of the lockdowns was offset by polluted air masses from elsewhere. There were small reductions in ozone and carbon monoxide in the free troposphere.
Victor Lannuque, Bastien Sauvage, Brice Barret, Hannah Clark, Gilles Athier, Damien Boulanger, Jean-Pierre Cammas, Jean-Marc Cousin, Alain Fontaine, Eric Le Flochmoën, Philippe Nédélec, Hervé Petetin, Isabelle Pfaffenzeller, Susanne Rohs, Herman G. J. Smit, Pawel Wolff, and Valérie Thouret
Atmos. Chem. Phys., 21, 14535–14555, https://doi.org/10.5194/acp-21-14535-2021, https://doi.org/10.5194/acp-21-14535-2021, 2021
Short summary
Short summary
The African intertropical troposphere is one of the world areas where the increase in ozone mixing ratio has been most pronounced since 1980 and where high carbon monoxide mixing ratios are found in altitude. In this article, IAGOS aircraft measurements, IASI satellite instrument observations, and SOFT-IO model products are used to explore the seasonal distribution variations and the origin of ozone and carbon monoxide over the African upper troposphere.
Romain Blot, Philippe Nedelec, Damien Boulanger, Pawel Wolff, Bastien Sauvage, Jean-Marc Cousin, Gilles Athier, Andreas Zahn, Florian Obersteiner, Dieter Scharffe, Hervé Petetin, Yasmine Bennouna, Hannah Clark, and Valérie Thouret
Atmos. Meas. Tech., 14, 3935–3951, https://doi.org/10.5194/amt-14-3935-2021, https://doi.org/10.5194/amt-14-3935-2021, 2021
Short summary
Short summary
A lack of information about temporal changes in measurement uncertainties is an area of concern for long-term trend studies of the key compounds which have a direct or indirect impact on climate change. The IAGOS program has measured O3 and CO within the troposphere and lower stratosphere for more than 25 years. In this study, we demonstrated that the IAGOS database can be treated as one continuous program and is therefore appropriate for studies of long-term trends.
Keun-Ok Lee, Brice Barret, Eric L. Flochmoën, Pierre Tulet, Silvia Bucci, Marc von Hobe, Corinna Kloss, Bernard Legras, Maud Leriche, Bastien Sauvage, Fabrizio Ravegnani, and Alexey Ulanovsky
Atmos. Chem. Phys., 21, 3255–3274, https://doi.org/10.5194/acp-21-3255-2021, https://doi.org/10.5194/acp-21-3255-2021, 2021
Short summary
Short summary
This paper focuses on the emission sources and pathways of pollution from the boundary layer to the Asian monsoon anticyclone (AMA) during the StratoClim aircraft campaign period. Simulations with the Meso-NH cloud-chemistry model at a horizontal resolution of 15 km are performed over the Asian region to characterize the impact of monsoon deep convection on the composition of AMA and on the formation of the Asian tropopause aerosol layer during the StratoClim campaign.
Brice Barret, Emanuele Emili, and Eric Le Flochmoen
Atmos. Meas. Tech., 13, 5237–5257, https://doi.org/10.5194/amt-13-5237-2020, https://doi.org/10.5194/amt-13-5237-2020, 2020
Short summary
Short summary
The IASI satellite sensor is used to document the variability and evolution of tropospheric ozone (O3). IASI O3 retrievals generally use a single a priori profile which can be responsible for biases and too-low variability. We have therefore implemented a dynamical a priori profile based on pixel location, month and tropopause height. Comparison with 10 years of global ozonesonde profiles shows large improvements in the retrieved tropospheric O3, with biases corrected and enhanced variabilities.
Martin Cussac, Virginie Marécal, Valérie Thouret, Béatrice Josse, and Bastien Sauvage
Atmos. Chem. Phys., 20, 9393–9417, https://doi.org/10.5194/acp-20-9393-2020, https://doi.org/10.5194/acp-20-9393-2020, 2020
Short summary
Short summary
Biomass burning emissions are a major source of carbon monoxide in the atmosphere. Here, the vertical transport that these emissions can undergo until the upper troposphere is investigated, as well as their contribution to carbon monoxide concentrations. It was found that boreal forest emissions were specific to the occurrence of pyroconvection directly above the fires, whereas biomass burning emissions from other regions of the globe relied more on the occurrence of deep convection.
Frank Roux, Hannah Clark, Kuo-Ying Wang, Susanne Rohs, Bastien Sauvage, and Philippe Nédélec
Atmos. Chem. Phys., 20, 3945–3963, https://doi.org/10.5194/acp-20-3945-2020, https://doi.org/10.5194/acp-20-3945-2020, 2020
Short summary
Short summary
Ozone, carbon monoxide and relative humidity were measured by two China Airlines aircraft equipped with IAGOS instruments during the summer of 2016. We examined landing and take-off profiles near Taipei (Taiwan), in the vicinity of three typhoons, in relation to ERA-5 meteorological reanalyses. Upstream of the storms, these data suggest that air is transported downwards from the stratosphere. Downstream, the troposphere is cleaner and moister due to the uplift of marine boundary layer air.
Philipp Reutter, Patrick Neis, Susanne Rohs, and Bastien Sauvage
Atmos. Chem. Phys., 20, 787–804, https://doi.org/10.5194/acp-20-787-2020, https://doi.org/10.5194/acp-20-787-2020, 2020
Short summary
Short summary
This study compares in situ measurements of temperature and humidity in the upper troposphere and lower stratosphere with reanalysis data from the ECMWF ERA-Interim data set. It is shown that temperature compares well between both data sets. However, extreme values of relative humidity with respect to ice (RHi) are missing in ERA-Interim, and hence the number and size of ice supersaturated regions differ strongly between both data sets.
Corinna Kloss, Gwenaël Berthet, Pasquale Sellitto, Felix Ploeger, Silvia Bucci, Sergey Khaykin, Fabrice Jégou, Ghassan Taha, Larry W. Thomason, Brice Barret, Eric Le Flochmoen, Marc von Hobe, Adriana Bossolasco, Nelson Bègue, and Bernard Legras
Atmos. Chem. Phys., 19, 13547–13567, https://doi.org/10.5194/acp-19-13547-2019, https://doi.org/10.5194/acp-19-13547-2019, 2019
Short summary
Short summary
With satellite measurements and transport models, we show that a plume resulting from strong Canadian fires in July/August 2017 was not only distributed throughout the northern/higher latitudes, but also reached the faraway tropics, aided by the circulation of Asian monsoon anticyclone. The regional climate impact in the wider Asian monsoon area in September exceeds the impact of the Asian tropopause aerosol layer by a factor of ~ 3 and compares to that of an advected moderate volcanic eruption.
Emanuele Emili, Brice Barret, Eric Le Flochmoën, and Daniel Cariolle
Atmos. Meas. Tech., 12, 3963–3984, https://doi.org/10.5194/amt-12-3963-2019, https://doi.org/10.5194/amt-12-3963-2019, 2019
Short summary
Short summary
We examine the differences between assimilating ozone profiles retrieved from IASI or the corresponding infrared spectra in a chemical transport model. This allows the impact of the retrieval's prior information on ozone reanalyses to be quantified. We found that significant differences can arise between the two approaches, depending on the latitude. An improved O3 variability is obtained assimilating IASI radiances directly. The implications for coupled Earth system models are discussed.
Hervé Petetin, Bastien Sauvage, Mark Parrington, Hannah Clark, Alain Fontaine, Gilles Athier, Romain Blot, Damien Boulanger, Jean-Marc Cousin, Philippe Nédélec, and Valérie Thouret
Atmos. Chem. Phys., 18, 17277–17306, https://doi.org/10.5194/acp-18-17277-2018, https://doi.org/10.5194/acp-18-17277-2018, 2018
Short summary
Short summary
This study derives a climatology of the impact of biomass burning versus anthropogenic emissions on the strongest CO plumes observed in the troposphere based on a dataset of about 30 000 in situ vertical profiles, combined with Lagrangian simulations coupled to CO emission. Results demonstrate the large contribution of biomass burning to the strongest CO plumes encountered in the troposphere in many locations of the world.
Hervé Petetin, Bastien Sauvage, Herman G. J. Smit, François Gheusi, Fabienne Lohou, Romain Blot, Hannah Clark, Gilles Athier, Damien Boulanger, Jean-Marc Cousin, Philippe Nedelec, Patrick Neis, Susanne Rohs, and Valérie Thouret
Atmos. Chem. Phys., 18, 9561–9581, https://doi.org/10.5194/acp-18-9561-2018, https://doi.org/10.5194/acp-18-9561-2018, 2018
Short summary
Short summary
Based on the numerous profiles available since 1994, this paper investigates the vertical stratification of ozone, carbon monoxide and relative humidity in the lower part of the troposphere (planetary boundary layer, lower free troposphere). Such a characterization of the vertical distribution of pollution is notably important for better understanding vertical exchanges and evaluating models on the vertical dimension.
Hélène Peiro, Emanuele Emili, Daniel Cariolle, Brice Barret, and Eric Le Flochmoën
Atmos. Chem. Phys., 18, 6939–6958, https://doi.org/10.5194/acp-18-6939-2018, https://doi.org/10.5194/acp-18-6939-2018, 2018
Short summary
Short summary
Tropospheric ozone (O3) is the third most important greenhouse gas. Several sensors on satellites measure O3 concentration like the infrared sounding IASI of MetOp satellites with a spatiotemporal coverage never reached so far. The assimilation of tropospheric IASI data within the chemistry transport model MOCAGE gives a good representation of O3 variability over the tropics linked with ENSO and the Walker circulation. IASI assimilation can contribute to the long-term monitoring of O3.
Yann Cohen, Hervé Petetin, Valérie Thouret, Virginie Marécal, Béatrice Josse, Hannah Clark, Bastien Sauvage, Alain Fontaine, Gilles Athier, Romain Blot, Damien Boulanger, Jean-Marc Cousin, and Philippe Nédélec
Atmos. Chem. Phys., 18, 5415–5453, https://doi.org/10.5194/acp-18-5415-2018, https://doi.org/10.5194/acp-18-5415-2018, 2018
Short summary
Short summary
Measurements of ozone and carbon monoxide were performed during 1994–2013 around the tropopause on board commercial aircraft. Seasonal cycles and trends were calculated above eight well-sampled regions in Northern Hemisphere midlatitudes. CO shows decreasing concentrations over the last 10 years, thus reflecting the impact of the legislation on anthropogenic emissions. Ozone amounts increased over the 20 years in the upper troposphere during different seasons, depending on the longitudes.
Bastien Sauvage, Alain Fontaine, Sabine Eckhardt, Antoine Auby, Damien Boulanger, Hervé Petetin, Ronan Paugam, Gilles Athier, Jean-Marc Cousin, Sabine Darras, Philippe Nédélec, Andreas Stohl, Solène Turquety, Jean-Pierre Cammas, and Valérie Thouret
Atmos. Chem. Phys., 17, 15271–15292, https://doi.org/10.5194/acp-17-15271-2017, https://doi.org/10.5194/acp-17-15271-2017, 2017
Short summary
Short summary
We provide the scientific community with a SOFT-IO tool based on the coupling of Lagrangian modeling with emission inventories and aircraft CO measurements, which is able to calculate the contribution of the sources and geographical origins of CO measurements, with good performances. Calculated CO added-value products will help scientists in interpreting large IAGOS CO data set. SOFT-IO could further be applied to other CO data sets or used to help validate emission inventories.
Marine Claeys, Greg Roberts, Marc Mallet, Jovanna Arndt, Karine Sellegri, Jean Sciare, John Wenger, and Bastien Sauvage
Atmos. Chem. Phys., 17, 7891–7915, https://doi.org/10.5194/acp-17-7891-2017, https://doi.org/10.5194/acp-17-7891-2017, 2017
Short summary
Short summary
Over a period of 5 days (summer 2013), the mass concentration of primary marine aerosols was dominant compared to other aerosols measured at a ground-based measuring site on Corsica. The characteristics of primary marine aerosols such as their size distribution, their optical properties and their direct radiative effect were studied as a function of their ageing and region of emission. These characteristics were compared to two other periods dominated by different aerosol regimes.
Hervé Petetin, Valérie Thouret, Alain Fontaine, Bastien Sauvage, Giles Athier, Romain Blot, Damien Boulanger, Jean-Marc Cousin, and Philippe Nédélec
Atmos. Chem. Phys., 16, 15147–15163, https://doi.org/10.5194/acp-16-15147-2016, https://doi.org/10.5194/acp-16-15147-2016, 2016
Short summary
Short summary
Ozone (O3) and carbon monoxide (CO) are two compounds of major importance in the atmosphere. In this paper we investigated their variability and trends at Frankfurt based on the MOZAIC–IAGOS dataset, a unique dataset of about 21 300 vertical profiles recorded by commercial aircraft. The CO concentrations have been decreasing since 2002, while no strong tendency is observed for O3 since 1994. However, the O3 seasonal variations are changing, with the spring maximum occurring earlier and earlier.
François Gheusi, Pierre Durand, Nicolas Verdier, François Dulac, Jean-Luc Attié, Philippe Commun, Brice Barret, Claude Basdevant, Antoine Clenet, Solène Derrien, Alexis Doerenbecher, Laaziz El Amraoui, Alain Fontaine, Emeric Hache, Corinne Jambert, Elodie Jaumouillé, Yves Meyerfeld, Laurent Roblou, and Flore Tocquer
Atmos. Meas. Tech., 9, 5811–5832, https://doi.org/10.5194/amt-9-5811-2016, https://doi.org/10.5194/amt-9-5811-2016, 2016
Short summary
Short summary
Boundary-layer pressurised balloons allow for horizontal multi-day flights in the lower atmosphere, carrying light scientific payloads. Ozonesondes, usually used for balloon soundings have too short a lifetime for such flights. An adaptation is proposed, whereby conventional sondes are operated with short measurement phases alternating with longer periods of dormancy. The sondes were operated over the western Mediterranean, offering an original perspective on tropospheric ozone.
Sarah Safieddine, Anne Boynard, Nan Hao, Fuxiang Huang, Lili Wang, Dongsheng Ji, Brice Barret, Sachin D. Ghude, Pierre-François Coheur, Daniel Hurtmans, and Cathy Clerbaux
Atmos. Chem. Phys., 16, 10489–10500, https://doi.org/10.5194/acp-16-10489-2016, https://doi.org/10.5194/acp-16-10489-2016, 2016
Short summary
Short summary
The Asian Summer Monsoon has implication on the weather and climate system as well as pollutants concentration over the monsoon regions leading to effects on the global air quality. Our results, combining satellite, aircraft and ground station data, show that tropospheric ozone, decrease during the period May–August over East and South Asia due to the Monsoon. The magnitude of this drop depends largely on meteorology and geographic location.
Alicia Gressent, Bastien Sauvage, Daniel Cariolle, Mathew Evans, Maud Leriche, Céline Mari, and Valérie Thouret
Atmos. Chem. Phys., 16, 5867–5889, https://doi.org/10.5194/acp-16-5867-2016, https://doi.org/10.5194/acp-16-5867-2016, 2016
Short summary
Short summary
In chemical transport models, NOx emitted by lightning (LNOx) is instantaneously diluted into the grid. A plume-in-grid parameterization to account for the sub-grid chemistry of LNOx is presented. This approach was implemented into the GEOS-Chem model and leads to a relative increase of NOx and O3 (18 % and 2 %, respectively, in July) on a large scale downwind of lightning emissions and a relative decrease (25 % and 8 %, respectively, over central Africa in July) over the regions of emissions.
Xuewu Fu, Nicolas Marusczak, Lars-Eric Heimbürger, Bastien Sauvage, François Gheusi, Eric M. Prestbo, and Jeroen E. Sonke
Atmos. Chem. Phys., 16, 5623–5639, https://doi.org/10.5194/acp-16-5623-2016, https://doi.org/10.5194/acp-16-5623-2016, 2016
J.-F. Léon, P. Augustin, M. Mallet, T. Bourrianne, V. Pont, F. Dulac, M. Fourmentin, D. Lambert, and B. Sauvage
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-15-9507-2015, https://doi.org/10.5194/acpd-15-9507-2015, 2015
Preprint withdrawn
Short summary
Short summary
This paper presents the aerosol vertical distribution observed by lidar soundings in Corsica (western Mediterranean) between February 2012 and August 2013. A seasonal cycle is observed in the extinction coefficient profiles and aerosol optical thickness with minima in winter and maxima in spring-summer. Less than 10% of the daily observations show high AOD corresponding to the large-scale advection of desert dust from Northern Africa or pollution aerosols from Europe.
C. Crevoisier, C. Clerbaux, V. Guidard, T. Phulpin, R. Armante, B. Barret, C. Camy-Peyret, J.-P. Chaboureau, P.-F. Coheur, L. Crépeau, G. Dufour, L. Labonnote, L. Lavanant, J. Hadji-Lazaro, H. Herbin, N. Jacquinet-Husson, S. Payan, E. Péquignot, C. Pierangelo, P. Sellitto, and C. Stubenrauch
Atmos. Meas. Tech., 7, 4367–4385, https://doi.org/10.5194/amt-7-4367-2014, https://doi.org/10.5194/amt-7-4367-2014, 2014
E. Emili, B. Barret, S. Massart, E. Le Flochmoen, A. Piacentini, L. El Amraoui, O. Pannekoucke, and D. Cariolle
Atmos. Chem. Phys., 14, 177–198, https://doi.org/10.5194/acp-14-177-2014, https://doi.org/10.5194/acp-14-177-2014, 2014
Related subject area
Subject: Gases | Research Activity: Atmospheric Modelling and Data Analysis | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
Representing improved tropospheric ozone distribution over the Northern Hemisphere by including lightning NOx emissions in CHIMERE
Assessing the ability to quantify the decrease in NOx anthropogenic emissions in 2019 compared to 2005 using OMI and TROPOMI satellite observations
Tracking daily NOx emissions from an urban agglomeration based on TROPOMI NO2 and a local ensemble transform Kalman filter
Evaluation of O3, H2O, CO, and NOy climatologies simulated by four global models in the upper troposphere–lower stratosphere with IAGOS measurements
Source contribution to ozone pollution during June 2021 fire events in Arizona: insights from WRF-Chem-tagged O3 and CO
High-resolution mapping of on-road vehicle emissions with real-time traffic datasets based on big data
Sensitivity of climate–chemistry model simulated atmospheric composition to the application of an inverse relationship between NOx emission and lightning flash frequency
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
Shifts in global atmospheric oxidant chemistry from land cover change
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
A New Parameterization of Photolysis Rates for Oxygenated Volatile Organic Compounds (OVOCs)
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
Simulated photochemical response to observational constraints on aerosol vertical distribution over North China
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
The 21st-century wetting inhibits growing surface ozone in Northwestern China
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
The impact of sea spray aerosol on photochemical ozone formation over eastern China: heterogeneous reaction of chlorine particles and radiative effect
Insights into ozone pollution control in urban areas by decoupling meteorological factors based on machine learning
Improving the computation efficiency of a source-oriented chemical mechanism for the simultaneous source apportionment of ozone and secondary particulate pollutants
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
Climate-driven biogenic emissions alleviate the impact of man-made emission reduction on O3 control in Pearl River Delta region, southern China
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
Sanhita Ghosh, Arineh Cholakian, Sylvain Mailler, and Laurent Menut
Atmos. Chem. Phys., 25, 6273–6297, https://doi.org/10.5194/acp-25-6273-2025, https://doi.org/10.5194/acp-25-6273-2025, 2025
Short summary
Short summary
In this study, we evaluate the present state of modelling lightning flashes over the Northern Hemisphere, using the classical CTH (cloud-top height) scheme and the ICEFLUX scheme with the CHIMERE model. Our study provides a comprehensive 3D comparison of model outputs to assess the robustness and applicability of these schemes. An improvement in O3 distribution in the tropical free troposphere is observed due to inclusion of LNOx (nitrogen oxide emissions from lightning) in the model. Inclusion of LNOx also reduces the lifetime of trace gas CH4.
Audrey Fortems-Cheiney, Grégoire Broquet, Elise Potier, Antoine Berchet, Isabelle Pison, Adrien Martinez, Robin Plauchu, Rimal Abeed, Aurélien Sicsik-Paré, Gaelle Dufour, Adriana Coman, Dilek Savas, Guillaume Siour, Henk Eskes, Hugo A. C. Denier van der Gon, and Stijn N. C. Dellaert
Atmos. Chem. Phys., 25, 6047–6068, https://doi.org/10.5194/acp-25-6047-2025, https://doi.org/10.5194/acp-25-6047-2025, 2025
Short summary
Short summary
This study assesses the potential of the Ozone Monitoring Instrument (OMI) and the TROPOspheric Monitoring Instrument (TROPOMI) satellite observations to inform about the decrease in anthropogenic emissions of nitrogen oxides (NOx) in 2019 compared with 2005 at regional to national scales in Europe. Both the OMI and TROPOMI inversions show decreases in European NOx anthropogenic emission budgets in 2019 compared to 2005 but with different magnitudes.
Yawen Kong, Bo Zheng, and Yuxi Liu
Atmos. Chem. Phys., 25, 5959–5976, https://doi.org/10.5194/acp-25-5959-2025, https://doi.org/10.5194/acp-25-5959-2025, 2025
Short summary
Short summary
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 lockdowns) and improve fine-scale air quality modeling.
Yann Cohen, Didier Hauglustaine, Nicolas Bellouin, Marianne Tronstad Lund, Sigrun Matthes, Agnieszka Skowron, Robin Thor, Ulrich Bundke, Andreas Petzold, Susanne Rohs, Valérie Thouret, Andreas Zahn, and Helmut Ziereis
Atmos. Chem. Phys., 25, 5793–5836, https://doi.org/10.5194/acp-25-5793-2025, https://doi.org/10.5194/acp-25-5793-2025, 2025
Short summary
Short summary
The chemical composition of the atmosphere near the tropopause is a key parameter for evaluating the climate impact of subsonic aviation pollutants. This study uses in situ data collected aboard passenger aircraft to assess the ability of four chemistry–climate models to reproduce (bi-)decadal climatologies of ozone, carbon monoxide, water vapour, and reactive nitrogen in this region. The models reproduce the very distinct ozone seasonality in the upper troposphere and in the lower stratosphere well.
Yafang Guo, Mohammad Amin Mirrezaei, Armin Sorooshian, and Avelino F. Arellano
Atmos. Chem. Phys., 25, 5591–5616, https://doi.org/10.5194/acp-25-5591-2025, https://doi.org/10.5194/acp-25-5591-2025, 2025
Short summary
Short summary
We assess the contributions of fire and anthropogenic emissions to O3 levels in Phoenix, Arizona, during a period of intense heat and drought conditions. We find that fire exacerbates O3 pollution and that interactions between weather, climate, and air chemistry are important to consider. This has implications for activities related to formulating emission reduction strategies in areas that are currently understudied yet becoming relevant due to reports of increasing global aridity.
Yujia Wang, Hongbin Wang, Bo Zhang, Peng Liu, Xinfeng Wang, Shuchun Si, Likun Xue, Qingzhu Zhang, and Qiao Wang
Atmos. Chem. Phys., 25, 5537–5555, https://doi.org/10.5194/acp-25-5537-2025, https://doi.org/10.5194/acp-25-5537-2025, 2025
Short summary
Short summary
This study established a bottom-up approach that employs real-time traffic flows and interpolation to obtain a spatially continuous on-road vehicle emission mapping for the main urban area of Jinan. The diurnal variation, spatial distribution, and emission hotspots were analyzed with clustering and hotspot analysis, showing unique fine-scale variation characteristics of on-road vehicle emissions. Future scenario analysis demonstrates remarkable benefits of electrification on emission reduction.
Francisco J. Pérez-Invernón, Francisco J. Gordillo-Vázquez, Heidi Huntrieser, Patrick Jöckel, and Eric J. Bucsela
Atmos. Chem. Phys., 25, 5557–5575, https://doi.org/10.5194/acp-25-5557-2025, https://doi.org/10.5194/acp-25-5557-2025, 2025
Short summary
Short summary
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.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Ryan Vella, Sergey Gromov, Clara M. Nussbaumer, Laura Stecher, Matthias Kohl, Samuel Ruhl, Holger Tost, Jos Lelieveld, and Andrea Pozzer
EGUsphere, https://doi.org/10.5194/egusphere-2025-1800, https://doi.org/10.5194/egusphere-2025-1800, 2025
Short summary
Short summary
We evaluated how replacing forests with farmland and grazing areas affects atmospheric composition. Using a global climate-chemistry model, we found that deforestation reduces BVOCs, increases farming pollutants, and shifts ozone chemistry. These changes lead to a small cooling effect on the climate. Restoring natural vegetation could reverse some of these effects.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Yuwen Peng, Bin Yuan, Sihang Wang, Xin Song, Zhe Peng, Wenjie Wang, Suxia Yang, Jipeng Qi, Xianjun He, Yibo Huangfu, Xiao-Bing Li, and Min Shao
EGUsphere, https://doi.org/10.5194/egusphere-2025-1649, https://doi.org/10.5194/egusphere-2025-1649, 2025
Short summary
Short summary
A structural-based parameterization for the photolysis rates of oxygenated volatile organic compounds (OVOCs) was integrated into an updated chemical mechanism. This method links photolysis rates to species' structure, bypassing limitations of insufficient quantum yield data. Box model results show that non-HCHO OVOCs, particularly multifunctional carbonyl compounds, significantly contribute to radical production, with alkene and aromatic oxidation products playing key roles.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Xi Chen, Ke Li, Ting Yang, Xipeng Jin, Lei Chen, Yang Yang, Shuman Zhao, Bo Hu, Bin Zhu, Zifa Wang, and Hong Liao
EGUsphere, https://doi.org/10.5194/egusphere-2025-430, https://doi.org/10.5194/egusphere-2025-430, 2025
Short summary
Short summary
Aerosol vertical distribution that plays a crucial role in aerosol-photolysis interaction (API) remains underrepresented in chemical models. We integrated lidar and radiosonde observations to constrain the simulated aerosol profiles over North China and quantified the photochemical responses. The increased photolysis rates in the lower layers led to increased ozone and accounted for a 36 %–56 % reduction in API effects, resulting in enhanced atmospheric oxidizing capacity and aerosol formation.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Xiaodong Zhang, Yu Yan, Ning Zhang, Wenpeng Wang, Huabing Suo, Xiaohu Jian, Chao Wang, Haibo Ma, Hong Gao, Zhaoli Yang, Tao Huang, and Jianmin Ma
EGUsphere, https://doi.org/10.5194/egusphere-2025-258, https://doi.org/10.5194/egusphere-2025-258, 2025
Short summary
Short summary
This study performed comprehensive sensitivity model simulations to explore the surface O3 responses to historical and projected climate change in Northwestern China (NW). Our results reveal that substantial wetting trends since the 21st century have mitigated O3 growth in this region, with the influence of wetting on O3 evolution outweighing the warming effect. These findings should be taken into account in future policymaking aimed at scientifically reducing O3 pollution in NW.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Yingying Hong, Yuqi Zhu, Yuxuan Huang, Yiming Liu, Chuqi Xiong, and Qi Fan
EGUsphere, https://doi.org/10.5194/egusphere-2024-4132, https://doi.org/10.5194/egusphere-2024-4132, 2025
Short summary
Short summary
This study investigates the impact of sea spray aerosol on ozone formation across Eastern China, highlighting its complex influence through both chemical reactions and radiative effects, which vary seasonally and geographically.
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
Short summary
Short summary
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.
Qixiang Xu, Fangcheng Su, Ke Wang, Ruiqin Zhang, Qi Ying, and Michael J. Kleeman
EGUsphere, https://doi.org/10.5194/egusphere-2025-44, https://doi.org/10.5194/egusphere-2025-44, 2025
Short summary
Short summary
This manuscript introduces a novel approach for improving the computational efficiency and scalability of source-oriented chemical mechanisms by simplifying the representation of reactions involving source-tagged species and implementing a source-oriented Euler Backward Iterative (EBI) solver. These advancements reduce simulation times by up to 74 % while maintaining accuracy, offering significant practical benefits for long-term source apportionment studies.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Nan Wang, Song Liu, Jiawei Xu, Yanyu Wang, Chun Li, Hua Lu, and Fumo Yang
EGUsphere, https://doi.org/10.5194/egusphere-2024-3771, https://doi.org/10.5194/egusphere-2024-3771, 2025
Short summary
Short summary
We found that climate warming and changes in vegetation have increased biogenic volatile organic compound emissions in the Pearl River Delta region. These increasing natural emissions, mainly due to climate warming, are weakening the benefits of reducing man-made emission control, leading to higher ozone levels. This work helps us understand how climate change influences air quality and provides important insights for improving pollution control strategies in the future.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Cited articles
Barret, B., Turquety, S., Hurtmans, D., Clerbaux, C., Hadji-Lazaro, J., Bey, I., Auvray, M., and Coheur, P.-F.: Global carbon monoxide vertical distributions from spaceborne high-resolution FTIR nadir measurements, Atmos. Chem. Phys., 5, 2901–2914, https://doi.org/10.5194/acp-5-2901-2005, 2005.
Barret, B., Ricaud, P., Mari, C., Attié, J.-L., Bousserez, N., Josse, B., Le Flochmoën, E., Livesey, N. J., Massart, S., Peuch, V.-H., Piacentini, A., Sauvage, B., Thouret, V., and Cammas, J.-P.: Transport pathways of CO in the African upper troposphere during the monsoon season: a study based upon the assimilation of spaceborne observations, Atmos. Chem. Phys., 8, 3231–3246, https://doi.org/10.5194/acp-8-3231-2008, 2008.
Barret, B., Williams, J. E., Bouarar, I., Yang, X., Josse, B., Law, K., Pham, M., Le Flochmoën, E., Liousse, C., Peuch, V. H., Carver, G. D., Pyle, J. A., Sauvage, B., van Velthoven, P., Schlager, H., Mari, C., and Cammas, J.-P.: Impact of West African Monsoon convective transport and lightning NOx production upon the upper tropospheric composition: a multi-model study, Atmos. Chem. Phys., 10, 5719–5738, https://doi.org/10.5194/acp-10-5719-2010, 2010.
Barret, B., Le Flochmoen, E., Sauvage, B., Pavelin, E., Matricardi, M., and Cammas, J. P.: The detection of post-monsoon tropospheric ozone variability over south Asia using IASI data, Atmos. Chem. Phys., 11, 9533–9548, https://doi.org/10.5194/acp-11-9533-2011, 2011.
Bergman, J. W., Fierli, F., Jensen, E. J., Honomichl, S., and Pan, L. L.: Boundary layer sources for the Asian anticyclone: Regional contributions to a vertical conduit, J. Geophys. Res.-Atmos., 118, 2560–2575, https://doi.org/10.1002/jgrd.50142, 2013.
Bey, I., Jacob, D. J., Logan, J. A., and Yantosca, R. M.: Asian chemical outflow to the Pacific in spring: Origins, pathways, and budgets, J. Geophys. Res.-Atmos., 106, 23097–23113, https://doi.org/10.1029/2001jd000806, 2001.
Chen, W.-T., Liao, H., and Seinfeld, J. H.: Future climate impacts of direct radiative forcing of anthropogenic aerosols, tropospheric ozone, and long-lived greenhouse gases, J. Geophys. Res.-Atmos., 112, D14209, https://doi.org/10.1029/2006jd008051, 2007.
Clerbaux, C., Boynard, A., Clarisse, L., George, M., Hadji-Lazaro, J., Herbin, H., Hurtmans, D., Pommier, M., Razavi, A., Turquety, S., Wespes, C., and Coheur, P.-F.: Monitoring of atmospheric composition using the thermal infrared IASI/MetOp sounder, Atmos. Chem. Phys., 9, 6041–6054, https://doi.org/10.5194/acp-9-6041-2009, 2009.
Cristofanelli, P., Bracci, A., Sprenger, M., Marinoni, A., Bonafè, U., Calzolari, F., Duchi, R., Laj, P., Pichon, J. M., Roccato, F., Venzac, H., Vuillermoz, E., and Bonasoni, P.: Tropospheric ozone variations at the Nepal Climate Observatory-Pyramid (Himalayas, 5079 m a.s.l.) and influence of deep stratospheric intrusion events, Atmos. Chem. Phys., 10, 6537–6549, https://doi.org/10.5194/acp-10-6537-2010, 2010.
De Wachter, E., Barret, B., Le Flochmoën, E., Pavelin, E., Matricardi, M., Clerbaux, C., Hadji-Lazaro, J., George, M., Hurtmans, D., Coheur, P.-F., Nedelec, P., and Cammas, J. P.: Retrieval of MetOp-A/IASI CO profiles and validation with MOZAIC data, Atmos. Meas. Tech., 5, 2843–2857, https://doi.org/10.5194/amt-5-2843-2012, 2012.
Doherty, R. M., Stevenson, D. S., Collins, W. J., and Sanderson, M. G.: Influence of convective transport on tropospheric ozone and its precursors in a chemistry-climate model, Atmos. Chem. Phys., 5, 3205–3218, https://doi.org/10.5194/acp-5-3205-2005, 2005.
Dufour, G., Eremenko, M., Griesfeller, A., Barret, B., LeFlochmoën, E., Clerbaux, C., Hadji-Lazaro, J., Coheur, P.-F., and Hurtmans, D.: Validation of three different scientific ozone products retrieved from IASI spectra using ozonesondes, Atmos. Meas. Tech., 5, 611–630, https://doi.org/10.5194/amt-5-611-2012, 2012.
Eastham, S. D., Weisenstein, D. K., and Barrett, S. R. H.: Development and evaluation of the unified tropospheric-stratospheric chemistry extension (UCX) for the global chemistry-transport model GEOS-Chem, Atmos. Environ., 89, 52–63, https://doi.org/10.1016/j.atmosenv.2014.02.001, 2014.
Eremenko, M., Dufour, G., Foret, G., Keim, C., Orphal, J., Beekmann, M., Bergametti, G., and Flaud, J. M.: Tropospheric ozone distributions over Europe during the heat wave in July 2007 observed from infrared nadir spectra recorded by IASI, Geophys. Res. Lett., 35, L18805, https://doi.org/10.1029/2008gl034803, 2008.
Fiore, A., Jacob, D., Bey, I., Yantosca, R., Field, B., Fusco, A., and Wilkinson, J.: Background ozone over the United States in summer: Origin, trend, and contribution to pollution episodes, J. Geophys. Res.-Atmos., 107, ACH11-1–ACH11-25, https://doi.org/10.1029/2001JD000982, 2002.
Garny, H. and Randel, W.: Dynamic variability of the Asian monsoon anticyclone observed in potential vorticity and correlations with tracer distributions, J. Geophys. Res.-Atmos., 118, 13421–13433, https://doi.org/10.1002/2013JD020908, 2013.
George, M., Clerbaux, C., Hurtmans, D., Turquety, S., Coheur, P.-F., Pommier, M., Hadji-Lazaro, J., Edwards, D. P., Worden, H., Luo, M., Rinsland, C., and McMillan, W.: Carbon monoxide distributions from the IASI/METOP mission: evaluation with other space-borne remote sensors, Atmos. Chem. Phys., 9, 8317–8330, https://doi.org/10.5194/acp-9-8317-2009, 2009.
Heath, N. K. and Fuelberg, H. E.: Using a WRF simulation to examine regions where convection impacts the Asian summer monsoon anticyclone, Atmos. Chem. Phys., 14, 2055–2070, https://doi.org/10.5194/acp-14-2055-2014, 2014.
Hoskins, B. J. and Rodwell, M. J.: A Model of the Asian Summer Monsoon. Part I: The Global Scale, J. Atmos. Sci., 52, 1329–1340, 1995.
Jacob, D. J., Heikes, B. G., Fan, S. M., Logan, J. A., Mauzerall, D. L., Bradshaw, J. D., Singh, H. B., Gregory, G. L., Talbot, R. W., Blake, D. R., and Sachse, G. W.: Origin of ozone and NOx in the tropical troposphere: A photochemical analysis of aircraft observations over the South Atlantic basin, J. Geophys. Res.-Atmos., 101, 24235–24250, https://doi.org/10.1029/96jd00336, 1996.
Kar, J., Bremer, H., Drummond, J. R., Rochon, Y. J., Jones, D. B. A., Nichitiu, F., Zou, J., Liu, J., Gille, J. C., Edwards, D. P., Deeter, M. N., Francis, G., Ziskin, D., and Warner, J.: Evidence of vertical transport of carbon monoxide from Measurements of Pollution in the Troposphere (MOPITT), Geophys. Res. Lett., 31, L23105, https://doi.org/10.1029/2004gl021128, 2004.
Kunhikrishnan, T., Lawrence, M. G., von Kuhlmann, R., Richter, A., Ladstatter-Weissenmayer, A., and Burrows, J. P.: Analysis of tropospheric NOx over Asia using the model of atmospheric transport and chemistry (MATCH-MPIC) and GOME-satellite observations, Atmos. Environ., 38, 581–596, https://doi.org/10.1016/j.atmosenv.2003.09.074, 2004.
Kunhikrishnan, T., Lawrence, M. G., von Kuhlmann, R., Wenig, M. O., Asman, W. A. H., Richter, A., and Burrows, J. P.: Regional NOx emission strength for the Indian subcontinent and the impact of emissions from India and neighboring countries on regional O-3 chemistry, J. Geophys. Res.-Atmos., 111, D15301, https://doi.org/10.1029/2005jd006036, 2006.
Lawrence, M. G., von Kuhlmann, R., Salzmann, M., and Rasch, P. J.: The balance of effects of deep convective mixing on tropospheric ozone, Geophys. Res. Lett., 30, 1940, https://doi.org/10.1029/2003gl017644, 2003.
Li, Q. B., Jacob, D. J., Logan, J. A., Bey, I., Yantosca, R. M., Liu, H. Y., Martin, R. V., Fiore, A. M., Field, B. D., Duncan, B. N., and Thouret, V.: A tropospheric ozone maximum over the Middle East, Geophys. Res. Lett., 28, 3235–3238, https://doi.org/10.1029/2001gl013134, 2001.
Li, Q. B., Jiang, J. H., Wu, D. L., Read, W. G., Livesey, N. J., Waters, J. W., Zhang, Y. S., Wang, B., Filipiak, M. J., Davis, C. P., Turquety, S., Wu, S. L., Park, R. J., Yantosca, R. M., and Jacob, D. J.: Convective outflow of South Asian pollution: A global CTM simulation compared with EOS MLS observations, Geophys. Res. Lett., 32, L14826, https://doi.org/10.1029/2005gl022762, 2005.
Liousse, C., Guillaume, B., Grégoire, J. M., Mallet, M., Galy, C., Pont, V., Akpo, A., Bedou, M., Castéra, P., Dungall, L., Gardrat, E., Granier, C., Konaré, A., Malavelle, F., Mariscal, A., Mieville, A., Rosset, R., Serça, D., Solmon, F., Tummon, F., Assamoi, E., Yoboué, V., and Van Velthoven, P.: Updated African biomass burning emission inventories in the framework of the AMMA-IDAF program, with an evaluation of combustion aerosols, Atmos. Chem. Phys., 10, 9631–9646, https://doi.org/10.5194/acp-10-9631-2010, 2010.
Liu, J., Logan, J. A., Jones, D. B. A., Livesey, N. J., Megretskaia, I., Carouge, C., and Nedelec, P.: Analysis of CO in the tropical troposphere using Aura satellite data and the GEOS-Chem model: insights into transport characteristics of the GEOS meteorological products, Atmos. Chem. Phys., 10, 12207–12232, https://doi.org/10.5194/acp-10-12207-2010, 2010.
Liu, J., Logan, J. A., Murray, L. T., Pumphrey, H. C., Schwartz, M. J., and Megretskaia, I. A.: Transport analysis and source attribution of seasonal and interannual variability of CO in the tropical upper troposphere and lower stratosphere, Atmos. Chem. Phys., 13, 129–146, https://doi.org/10.5194/acp-13-129-2013, 2013.
Liu, J. J., Jones, D. B. A., Worden, J. R., Noone, D., Parrington, M., and Kar, J.: Analysis of the summertime buildup of tropospheric ozone abundances over the Middle East and North Africa as observed by the Tropospheric Emission Spectrometer instrument, J. Geophys. Res.-Atmos., 114, D05304, https://doi.org/10.1029/2008jd010993, 2009.
Marenco, A., Thouret, V., Nedelec, P., Smit, H., Helten, M., Kley, D., Karcher, F., Simon, P., Law, K., Pyle, J., Poschmann, G., Von Wrede, R., Hume, C., and Cook, T.: Measurement of ozone and water vapor by Airbus in-service aircraft: The MOZAIC airborne program, An overview, J. Geophys. Res.-Atmos., 103, 25631–25642, https://doi.org/10.1029/98jd00977, 1998.
Martin, R. V., Jacob, D., Logan, J., Bey, I., Yantosca, R., Staudt, A., Li, Q., Fiore, A., Duncan, B., Liu, H., Ginoux, P., and Thouret, V.: Interpretation of TOMS observations of tropical tropospheric ozone with a global model and in-situ observations, J. Geophys. Res.-Atmos., 107, ACH 4-1–ACH 4-27, https://doi.org/10.1029/2001JD001480, 2002.
Martin, R. V., Sauvage, B., Folkins, I., Sioris, C. E., Boone, C., Bernath, P., and Ziemke, J.: Space-based constraints on the production of nitric oxide by lightning, J. Geophys. Res.-Atmos., 112, D09309, https://doi.org/10.1029/2006jd007831, 2007.
McLinden, C. A., Olsen, S. C., Hannegan, B., Wild, O., Prather, M. J., and Sundet, J.: Stratospheric ozone in 3-D models: A simple chemistry and the cross-tropopause flux, J. Geophys. Res.-Atmos., 105, 14653–14665, https://doi.org/10.1029/2000jd900124, 2000.
Moorthi, S. and Suarez, M. J.: Relaxed Arakawa-Schubert – A parameterization of moist convection for general-circulation models, Mon. Weather Rev., 120, 978–1002, https://doi.org/10.1175/1520-0493(1992)120<0978:rasapo>2.0.co;2, 1992.
Murray, L., Jacob, D., Logan, J., Hudman, R., and Koshah, W.: Optimized regional and interannual variability of lightning in a global chemical transport model constrained by LIS/OTD satellite data, J. Geophys. Res.-Atmos., 117, D20307, https://doi.org/10.1029/2012JD017934, 2012.
Nassar, R., Logan, J. A., Megretskaia, I. A., Murray, L. T., Zhang, L., and Jones, D. B. A.: Analysis of tropical tropospheric ozone, carbon monoxide, and water vapor during the 2006 El Nino using TES observations and the GEOS-Chem model, J. Geophys. Res.-Atmos., 114, D17304, https://doi.org/10.1029/2009jd011760, 2009.
Nedelec, P., Cammas, J.-P., Thouret, V., Athier, G., Cousin, J.-M., Legrand, C., Abonnel, C., Lecoeur, F., Cayez, G., and Marizy, C.: An improved infrared carbon monoxide analyser for routine measurements aboard commercial Airbus aircraft: technical validation and first scientific results of the MOZAIC III programme, Atmos. Chem. Phys., 3, 1551–1564, https://doi.org/10.5194/acp-3-1551-2003, 2003.
Park, M., Randel, W. J., Gettelman, A., Massie, S. T., and Jiang, J. H.: Transport above the Asian summer monsoon anticyclone inferred from Aura Microwave Limb Sounder tracers, J. Geophys. Res.-Atmos., 112, D16309, https://doi.org/10.1029/2006jd008294, 2007.
Park, M., Randel, W. J., Emmons, L. K., Bernath, P. F., Walker, K. A., and Boone, C. D.: Chemical isolation in the Asian monsoon anticyclone observed in Atmospheric Chemistry Experiment (ACE-FTS) data, Atmos. Chem. Phys., 8, 757–764, https://doi.org/10.5194/acp-8-757-2008, 2008.
Park, M., Randel, W. J., Emmons, L. K., and Livesey, N. J.: Transport pathways of carbon monoxide in the Asian summer monsoon diagnosed from Model of Ozone and Related Tracers (MOZART), J. Geophys. Res.-Atmos., 114, D08303, https://doi.org/10.1029/2008jd010621, 2009.
Ploeger, F., Gottschling, C., Griessbach, S., Grooß, J.-U., Guenther, G., Konopka, P., Müller, R., Riese, M., Stroh, F., Tao, M., Ungermann, J., Vogel, B., and von Hobe, M.: A potential vorticity-based determination of the transport barrier in the Asian summer monsoon anticyclone, Atmos. Chem. Phys., 15, 13145–13159, https://doi.org/10.5194/acp-15-13145-2015, 2015.
Popovic, J. M. and Plumb, R. A.: Eddy shedding from the upper-tropospheric Asian monsoon anticyclone, J. Atmos. Sci., 58, 93–104, https://doi.org/10.1175/1520-0469(2001)058<0093:esftut>2.0.co;2, 2001.
Price, C. and Rind, D.: Modeling global lightning distributions in a general circulation model, Mon. Weather Rev., 122, 1930–1939, https://doi.org/10.1175/1520-0493(1994)122<1930:MGLDIA>2.0.CO;2, 1994.
Randel, W. J. and Park, M.: Deep convective influence on the Asian summer monsoon anticyclone and associated tracer variability observed with Atmospheric Infrared Sounder (AIRS), J. Geophys. Res.-Atmos., 111, D12314, https://doi.org/10.1029/2005jd006490, 2006.
Randel, W. J., Park, M., Emmons, L., Kinnison, D., Bernath, P., Walker, K. A., Boone, C., and Pumphrey, H.: Asian Monsoon Transport of Pollution to the Stratosphere, Science, 328, 611–613, https://doi.org/10.1126/science.1182274, 2010.
Rodgers, C. D.: Inverse methods for atmospheric sounding: Theory and Practice, Series on Atmospheric, Oceanic and Planetary Physics – Vol. 2, World Scientific, Singapore, New Jersey, London, Hong Kong, 238 pp., 2000.
Sauvage, B., Thouret, V., Cammas, J.-P., Gheusi, F., Athier, G., and Nédélec, P.: Tropospheric ozone over Equatorial Africa: regional aspects from the MOZAIC data, Atmos. Chem. Phys., 5, 311–335, https://doi.org/10.5194/acp-5-311-2005, 2005.
Sauvage, B., Martin, R. V., van Donkelaar, A., Liu, X., Chance, K., Jaeglé, L., Palmer, P. I., Wu, S., and Fu, T.-M.: Remote sensed and in situ constraints on processes affecting tropical tropospheric ozone, Atmos. Chem. Phys., 7, 815–838, https://doi.org/10.5194/acp-7-815-2007, 2007a.
Sauvage, B., Martin, R. V., van Donkelaar, A., and Ziemke, J. R.: Quantification of the factors controlling tropical tropospheric ozone and the South Atlantic maximum, J. Geophys. Res.-Atmos., 112, D11309, https://doi.org/10.1029/2006jd008008, 2007b.
Schumann, U. and Huntrieser, H.: The global lightning-induced nitrogen oxides source, Atmos. Chem. Phys., 7, 3823–3907, https://doi.org/10.5194/acp-7-3823-2007, 2007.
Shindell, D. T., Faluvegi, G., Stevenson, D. S., Krol, M. C., Emmons, L. K., Lamarque, J. F., Petron, G., Dentener, F. J., Ellingsen, K., Schultz, M. G., Wild, O., Amann, M., Atherton, C. S., Bergmann, D. J., Bey, I., Butler, T., Cofala, J., Collins, W. J., Derwent, R. G., Doherty, R. M., Drevet, J., Eskes, H. J., Fiore, A. M., Gauss, M., Hauglustaine, D. A., Horowitz, L. W., Isaksen, I. S. A., Lawrence, M. G., Montanaro, V., Mueller, J. F., Pitari, G., Prather, M. J., Pyle, J. A., Rast, S., Rodriguez, J. M., Sanderson, M. G., Savage, N. H., Strahan, S. E., Sudo, K., Szopa, S., Unger, N., van Noije, T. P. C., and Zeng, G.: Multimodel simulations of carbon monoxide: Comparison with observations and projected near-future changes, J. Geophys. Res.-Atmos., 111, D19306, https://doi.org/10.1029/2006jd007100, 2006.
Streets, D. G., Yu, C., Bergin, M. H., Wang, X. M., and Carmichael, G. R.: Modeling study of air pollution due to the manufacture of export goods in China's Pearl River Delta, Environ. Sci. Technol., 40, 2099–2107, https://doi.org/10.1021/es051275n, 2006.
Thouret, V., Marenco, A., Logan, J. A., Nedelec, P., and Grouhel, C.: Comparisons of ozone measurements from the MOZAIC airborne program and the ozone sounding network at eight locations, J. Geophys. Res.-Atmos., 103, 25695–25720, https://doi.org/10.1029/98jd02243, 1998.
Tocquer, F., Barret, B., Mari, C., Le Flochmoen, E., Cammas, J.-P., and Sauvage, B.: An upper tropospheric “ozone river” from Africa to India during the 2008 Asian post-monsoon season, Tellus B, 67, 25350, https://doi.org/10.3402/tellusb.v67.25350, 2015.
van der Werf, G. R., Randerson, J. T., Giglio, L., Collatz, G. J., Mu, M., Kasibhatla, P. S., Morton, D. C., DeFries, R. S., Jin, Y., and van Leeuwen, T. T.: Global fire emissions and the contribution of deforestation, savanna, forest, agricultural, and peat fires (1997–2009), Atmos. Chem. Phys., 10, 11707–11735, https://doi.org/10.5194/acp-10-11707-2010, 2010.
Vogel, B., Günther, G., Müller, R., Grooß, J.-U., and Riese, M.: Impact of different Asian source regions on the composition of the Asian monsoon anticyclone and of the extratropical lowermost stratosphere, Atmos. Chem. Phys., 15, 13699–13716, https://doi.org/10.5194/acp-15-13699-2015, 2015.
Wu, S., Mickley, L., Jacob, D., Logan, J., Yantosca, R., and Rind, D.: Why are there large differences between models in global budgets of tropospheric ozone?, J. Geophys. Atmos., 112, D05302, https://doi.org/10.1029/2006JD007801, 2007.
Yamasoe, M. A., Sauvage, B., Thouret, V., Nédélec, P., Le Flochmoen, E., and Barret, B.: Analysis of tropospheric ozone and carbon monoxide profiles over South America based on MOZAIC/IAGOS database and model simulations, Tellus B, 67, 27884, https://doi.org/10.3402/tellusb.v67.27884, 2015.
Yan, R. and Bian, J.: Tracing the boundary layer sources of carbon monoxide in the Asian summer monsoon anticyclone using WRF-Chem, Adv. Atmos. Sci., 32, 943–951, https://doi.org/10.1007/s00376-014-4130-3, 2015.
Zhang, Q., Wu, G., and Qian, Y.: Asia high and its relationship to the climate anomaly over East Asia in summer, J. Meteorol. Soc. Jpn., 80, 733–744, 2002.
Short summary
During the Asian Monsoon, pollutants are uplifted to the upper troposphere where they are trapped within the large scale Asian monsoon anticyclone. Among these pollutants are O3 precursors such as nitrogen oxides (NOx) and carbon monoxide (CO). Based on satellite observations and model simulations, we have estimated the impact of anthropogenic and natural sources on O3 in the monsoon anticyclone. Our results show that Asian pollution and LiNOx have comparable contributions.
During the Asian Monsoon, pollutants are uplifted to the upper troposphere where they are...
Altmetrics
Final-revised paper
Preprint