Articles | Volume 22, issue 16
https://doi.org/10.5194/acp-22-10657-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue:
https://doi.org/10.5194/acp-22-10657-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
23 Aug 2022
Research article |
| 23 Aug 2022
| 23 Aug 2022
Atmospheric impacts of chlorinated very short-lived substances over the recent past – Part 1: Stratospheric chlorine budget and the role of transport
Lancaster Environment Centre, Lancaster University, Lancaster, UK
now at: Sibley School of Mechanical and Aerospace Engineering, Cornell
University, Ithaca, NY, USA
Ryan Hossaini
Lancaster Environment Centre, Lancaster University, Lancaster, UK
Centre of Excellence in Environmental Data Science, Lancaster University,
Lancaster UK
Martyn P. Chipperfield
School of Earth and Environment, University of Leeds, Leeds, UK
National Centre for Earth Observation (NCEO), University of Leeds, Leeds,
UK
N. Luke Abraham
Department of Chemistry, University of Cambridge, Cambridge, UK
National Centre for Atmospheric Science (NCAS), University of Cambridge, Cambridge, UK
Peter Braesicke
Institute of Meteorology and Climate Research (IMK), Karlsruhe Institute of Technology, Karlsruhe, Germany
Related authors
Sean M. Davis, William T. Ball, Yue Jia, Gabriel Chiodo, Justin A. Alsing, James Keeble, Hideharu Akiyoshi, Carlo Arosio, Ewa M. Bednarz, Andreas Chrysanthou, Melanie Coldewey-Egbers, Robert Damadeo, Sandip Dhomse, Mohamadou A. Diallo, Simone Dietmuller, Roland Eichinger, Stacey Frith, Birgit Hassler, Michaela I. Hegglin, Daan Hubert, Patrick Jöckel, Béatrice Josse, Natalya Kramarova, Diego Loyola, Eliane Maillard Barras, Marion Marchand, Olaf Morgenstern, David Plummer, Robert W. Portmann, Karen H. Rosenlof, Alexei Rozanov, Viktoria F. Sofieva, Johannes Staehelin, Timofei Sukhodolov, Kleareti Tourpali, Ronald J. Van der A, H. J. Ray Wang, Krzysztof Wargan, Shingo Watanabe, Mark Weber, Jeannette D. Wild, Yousuke Yamashita, and Jerry Ziemke
Atmos. Chem. Phys., 26, 13817–13843, https://doi.org/10.5194/acp-26-13817-2026, https://doi.org/10.5194/acp-26-13817-2026, 2026
Short summary
Short summary
This study investigates tropical ozone changes in models and satellite observations to determine how well they agree and whether observations can constrain model projections. At some levels, satellite records disagree significantly on the magnitude of ozone changes. While early and late 21st century trends are correlated across models, suggesting a potential emergent constraint, the spread in observations means they are unable to provide guidance on the credibility of model projections.
Martin B. Andrews, Neal Butchart, James A. Anstey, Ewa Bednarz, Dillon Elsbury, Jorge L. García-Franco, Vinay Kumar, Froila M. Palmeiro, Natasha E. Trencham, Kohei Yoshida, Zhaoyang Chai, Dong-Chan Hong, Kai Huang, Aleena M. Jaison, Yoshio Kawatani, Jeff R. Knight, Pu Lin, François Lott, Yixiong Lu, Hiroaki Naoe, Scott M. Osprey, Jadwiga H. Richter, Federico Serva, Seok-Woo Son, Qi Tang, Shingo Watanabe, and Jinbo Xie
Weather Clim. Dynam., 7, 1797–1820, https://doi.org/10.5194/wcd-7-1797-2026, https://doi.org/10.5194/wcd-7-1797-2026, 2026
Short summary
Short summary
The observed winds in the upper atmosphere over the equator have alternating easterly and westerly regions that descend towards the lower atmosphere before dissipating, with a period of approximately 28 months. This is known as the Quasi-Biennial Oscillation (QBO). The QBO is known to influence remote regions of the atmosphere. This paper details the results of multi-model experiments where the QBO is nudged towards the observed QBO allowing the assessment of these remote connections.
Daniele Visioni, Alan Robock, Alistair Duffey, Matthew Henry, Haruki Hirasawa, Walker Raymond Lee, Cindy Wang, Kelsey Roberts, Shingo Watanabe, Michelle Simões Reboita, Masahiro Sugiyama, Ben Kravitz, Jim Haywood, Simone Tilmes, Frédéric K. Bonou, Jack Chen, Timofei Sukhodolov, Sandro Vattioni, Andrin Jörimann, Diego Villanueva, Ryan Vella, Paul Farron, Ewa Bednarz, Ulrike Niemeier, Colleen Golja, and Juan A. Añel
Geosci. Model Dev., 19, 8469–8499, https://doi.org/10.5194/gmd-19-8469-2026, https://doi.org/10.5194/gmd-19-8469-2026, 2026
Short summary
Short summary
The Geoengineering Model Intercomparison Project is a coordinated international model intercomparison effort aiming to provide robust experimental protocols for simulations of various Solar Radiation Modification (SRM) methods. In this manuscript, we describe a list of novel experiments decided by the community, to be run by climate models to better understand sources of uncertainty in SRM. We also show and discuss some preliminary results from a few climate models.
Ewa M. Bednarz, Amy H. Butler, James M. Haywood, Matthew Henry, Andy Jones, Ben Kravitz, Walker R. Lee, Douglas G. MacMartin, Amanda C. Maycock, Takashi Sekiya, Shingo Watanabe, and Daniele Visioni
Atmos. Chem. Phys., 26, 12751–12770, https://doi.org/10.5194/acp-26-12751-2026, https://doi.org/10.5194/acp-26-12751-2026, 2026
Short summary
Short summary
An assessment of the potential impacts of Stratospheric Aerosol Injection, a proposed method to offset global warming, on stratospheric ozone projections over the 21st century using the new multi-model GeoMIP (Geoengineering Model Intercomparison Project) G6-1.5K-SAI (Stratospheric Aerosol Injection) experiment. We discuss drivers of the responses, identify areas of model agreement and disagreement and sources of uncertainty. Our results highlight the need to assess any projected SAI impacts in wider strategy and scenario dimension using a multi-model framework.
Walker Raymond Lee, Simone Tilmes, and Ewa M. Bednarz
Earth Syst. Dynam., 17, 1117–1134, https://doi.org/10.5194/esd-17-1117-2026, https://doi.org/10.5194/esd-17-1117-2026, 2026
Short summary
Short summary
We present climate model simulation of stratospheric aerosol injection, a proposed method of climate intervention where reflective particles are placed in the stratosphere to cool the planet. We design our simulated interventions to maintain certain surface temperature patterns, and show that the same temperatures can be maintained in different ways because of how the ocean transports heat. This has implications for how climate intervention model experiments are designed in the future.
Ewa M. Bednarz, Valentina Aquila, Amy H. Butler, Peter Colarco, Eric Fleming, Freja F. Østerstrøm, David Plummer, Ilaria Quaglia, William Randel, Michelle L. Santee, Takashi Sekiya, Simone Tilmes, Xinyue Wang, Shingo Watanabe, Wandi Yu, Jun Zhang, Yunqian Zhu, and Zhihong Zhuo
Atmos. Chem. Phys., 26, 11355–11370, https://doi.org/10.5194/acp-26-11355-2026, https://doi.org/10.5194/acp-26-11355-2026, 2026
Short summary
Short summary
The 2022 Hunga eruption injected unprecedented quantities of water vapor into the stratosphere, alongside modest amounts of aerosol precursors. We assess its impacts on stratospheric ozone layer using a multi-model ensemble of chemistry-climate simulations. The results confirm the eruption's role in modulating SH (Southern Hemisphere) mid and high latitudes ozone abundances in the short term, and discuss the different chemical and dynamical processes driving those changes as well as the role of natural variability.
Andrin Jörimann, Timofei Sukhodolov, Simone Tilmes, David Plummer, Shingo Watanabe, Hideharu Akiyoshi, Gabriel Chiodo, Daniele Visioni, Sandro Vattioni, Eugene Rozanov, Ewa Monika Bednarz, Béatrice Josse, Yousuke Yamashita, and Thomas Peter
Atmos. Chem. Phys., 26, 11207–11234, https://doi.org/10.5194/acp-26-11207-2026, https://doi.org/10.5194/acp-26-11207-2026, 2026
Short summary
Short summary
We study a future scenario where artificial stratospheric aerosol injections counter medium climate change, to understand possible negative side effects like ozone depletion. The injected aerosol layer is implemented uniformly in five climate models, which eliminates some uncertainty from model-specific aerosol evolution. The models agree well on where and how key thermodynamical (heating, circulation) and chemical processes change, however, the strength of the changes varies considerably.
Colleen Marie Golja, Marianna Linz, Ewa Monika Bednarz, Daniele Visioni, Ben Kravitz, John A. Dykema, Michelle E. Frazer, Anthony C. Jones, Isla R. Simpson, and Shingo Watanabe
EGUsphere, https://doi.org/10.5194/egusphere-2026-4200, https://doi.org/10.5194/egusphere-2026-4200, 2026
Short summary
Short summary
Adding reflective particles to the stratosphere has been proposed to cool the planet, but how the resulting lower-stratospheric heating affects the broader climate remains unclear. This study simulates idealized lower-stratospheric heating across five climate models finding large inter-model differences in the stratospheric and surface response. The results highlight ways in which these differences may be explained by biases in the stratospheric climatological mean state.
Ilaria Quaglia, Daniele Visioni, Ewa M. Bednarz, Yunqian Zhu, Georgiy Stenchikov, Valentina Aquila, Cheng-Cheng Liu, Graham W. Mann, Yifeng Peng, Takashi Sekiya, Simone Tilmes, Xinyue Wang, Shingo Watanabe, Pengfei Yu, Jun Zhang, Wandi Yu, and Zhihong Zhuo
Atmos. Chem. Phys., 26, 7677–7704, https://doi.org/10.5194/acp-26-7677-2026, https://doi.org/10.5194/acp-26-7677-2026, 2026
Short summary
Short summary
On January 15, 2022, the Hunga volcano eruption released unprecedented amounts of water vapor into the atmosphere alongside a modest amount of SO2. In this work we analyse results from multiple Earth system models. The models agree that the eruption led to small negative radiative forcing from sulfate aerosols and that the contribution from water vapor was minimal. Therefore, the Hunga eruption cannot explain the exceptional surface warming observed in 2023.
Walker Raymond Lee, Daniele Visioni, Benjamin Moore Wagman, Christopher Robert Wentland, Ben Kravitz, Shingo Watanabe, Takashi Sekiya, Andy Jones, Jim Haywood, Matthew Henry, and Ewa Monika Bednarz
Atmos. Chem. Phys., 26, 7463–7483, https://doi.org/10.5194/acp-26-7463-2026, https://doi.org/10.5194/acp-26-7463-2026, 2026
Short summary
Short summary
Stratospheric aerosol injection (SAI) is a proposed method of cooling the planet by introducing reflective particles called aerosols into the middle atmosphere to reflect sunlight back into space. We consider recent simulations of SAI from four different climate models. SAI cools the planet effectively in all four models; we examine the impacts on temperature and precipitation in each model and compare to previous experiments. Our simulations will help inform future research and policy.
Jared Farley, Douglas G. MacMartin, Daniele Visioni, Ben Kravitz, Ewa M. Bednarz, Alistair Duffey, Matthew Henry, and Ali Akherati
Geosci. Model Dev., 19, 1809–1831, https://doi.org/10.5194/gmd-19-1809-2026, https://doi.org/10.5194/gmd-19-1809-2026, 2026
Short summary
Short summary
As the climate changes, many are studying sunlight reflection as a potential method of cooling. Such climate intervention could be deployed in many possible ways, including in scenarios where not every actor agrees on the strategy of cooling. These scenarios are so diverse that to explore all of them using earth system models proves to be too costly. In this paper, we develop a simplified climate model that allows users to easily explore climate intervention scenarios of their choice.
Cindy Wang, Daniele Visioni, Glen Chua, and Ewa M. Bednarz
Atmos. Chem. Phys., 26, 1339–1357, https://doi.org/10.5194/acp-26-1339-2026, https://doi.org/10.5194/acp-26-1339-2026, 2026
Short summary
Short summary
Stratospheric aerosol injection is a proposed method to slow global warming by adding tiny reflective particles high up in the atmosphere to cool the planet. We study how this proposed method might affect air quality and human health using climate models. We find that the health impacts would likely be small and are mainly driven by changes in climate, not by the particles themselves.
Clara Orbe, Alison Ming, Gabriel Chiodo, Michael Prather, Mohamadou Diallo, Qi Tang, Andreas Chrysanthou, Hiroaki Naoe, Xin Zhou, Irina Thaler, Dillon Elsbury, Ewa Bednarz, Jonathon S. Wright, Aaron Match, Shingo Watanabe, James Anstey, Tobias Kerzenmacher, Stefan Versick, Marion Marchand, Feng Li, and James Keeble
Geosci. Model Dev., 19, 773–794, https://doi.org/10.5194/gmd-19-773-2026, https://doi.org/10.5194/gmd-19-773-2026, 2026
Short summary
Short summary
The quasi-biennial oscillation (QBO) is the main source of wind fluctuations in the tropical stratosphere, which can couple to surface climate. However, models do a poor job of simulating the QBO in the lower stratosphere, for reasons that remain unclear. One possibility is that models do not completely represent how ozone influences the QBO-associated wind variations. Here we propose a multi-model framework for assessing how ozone influences the QBO in recent past and future climates.
Ewa M. Bednarz, Amy H. Butler, Xinyue Wang, Zhihong Zhuo, Wandi Yu, Georgiy Stenchikov, Matthew Toohey, and Yunqian Zhu
Atmos. Chem. Phys., 26, 197–215, https://doi.org/10.5194/acp-26-197-2026, https://doi.org/10.5194/acp-26-197-2026, 2026
Short summary
Short summary
We investigate whether the 2022 Hunga eruption could affect surface climate via indirect pathways using large ensembles of Earth System Model simulations. These suggest that the eruption could have a non-negligible influence on regional surface climate, and we discuss the mechanisms via which such an influence could occur but also highlight that the forcing is relatively weak compared to natural climate variability which significantly hinders the detection of such impacts in the real world.
Zhihong Zhuo, Xinyue Wang, Yunqian Zhu, Wandi Yu, Ewa M. Bednarz, Eric Fleming, Peter R. Colarco, Shingo Watanabe, David Plummer, Georgiy Stenchikov, William Randel, Adam Bourassa, Valentina Aquila, Takashi Sekiya, Mark R. Schoeberl, Simone Tilmes, Jun Zhang, Paul J. Kushner, and Francesco S. R. Pausata
Atmos. Chem. Phys., 25, 13161–13176, https://doi.org/10.5194/acp-25-13161-2025, https://doi.org/10.5194/acp-25-13161-2025, 2025
Short summary
Short summary
The 2022 Hunga eruption caused unprecedented stratospheric water injection, triggering unique atmospheric impacts. This study combines observations and model simulations, projecting a stratospheric water vapor anomaly lasting 4–7 years, with significant temperature variations and ozone depletion in the upper atmosphere lasting 7–10 years. These findings offer critical insights into the role of stratospheric water vapor in shaping climate and atmospheric chemistry.
Yunqian Zhu, Hideharu Akiyoshi, Valentina Aquila, Elizabeth Asher, Ewa M. Bednarz, Slimane Bekki, Christoph Brühl, Amy H. Butler, Parker Case, Simon Chabrillat, Gabriel Chiodo, Margot Clyne, Peter R. Colarco, Sandip Dhomse, Lola Falletti, Eric Fleming, Ben Johnson, Andrin Jörimann, Mahesh Kovilakam, Gerbrand Koren, Ales Kuchar, Nicolas Lebas, Qing Liang, Cheng-Cheng Liu, Graham Mann, Michael Manyin, Marion Marchand, Olaf Morgenstern, Paul Newman, Luke D. Oman, Freja F. Østerstrøm, Yifeng Peng, David Plummer, Ilaria Quaglia, William Randel, Samuel Rémy, Takashi Sekiya, Stephen Steenrod, Timofei Sukhodolov, Simone Tilmes, Kostas Tsigaridis, Rei Ueyama, Daniele Visioni, Xinyue Wang, Shingo Watanabe, Yousuke Yamashita, Pengfei Yu, Wandi Yu, Jun Zhang, and Zhihong Zhuo
Geosci. Model Dev., 18, 5487–5512, https://doi.org/10.5194/gmd-18-5487-2025, https://doi.org/10.5194/gmd-18-5487-2025, 2025
Short summary
Short summary
To understand the climate impact of the 2022 Hunga volcanic eruption, we developed a climate model–observation comparison project. The paper describes the protocols and models that participate in the experiments. We designed several experiments to achieve our goals of this activity: (1) to evaluate the climate model performance and (2) to understand the Earth system responses to this eruption.
Ezra Brody, Yan Zhang, Douglas G. MacMartin, Daniele Visioni, Ben Kravitz, and Ewa M. Bednarz
Earth Syst. Dynam., 16, 1325–1341, https://doi.org/10.5194/esd-16-1325-2025, https://doi.org/10.5194/esd-16-1325-2025, 2025
Short summary
Short summary
Stratospheric aerosol injection (SAI) is being studied as a possible supplement to emission reduction to temporarily mitigate some of the risks associated with climate change. The latitudes at which SAI is done determine the effect on the climate. We try to find if there are combinations of latitudes that do a better job of counteracting climate change than existing strategies. We found that there are, but just how significant these improvements are depends on the amount of cooling.
Simone Tilmes, Ewa M. Bednarz, Andrin Jörimann, Daniele Visioni, Douglas E. Kinnison, Gabriel Chiodo, and David Plummer
Atmos. Chem. Phys., 25, 6001–6023, https://doi.org/10.5194/acp-25-6001-2025, https://doi.org/10.5194/acp-25-6001-2025, 2025
Short summary
Short summary
In this paper, we describe the details of a new multi-model intercomparison experiment to assess the effects of Stratospheric Aerosol Intervention (SAI) on stratospheric chemistry and dynamics and, therefore, ozone. Second, we discuss the advantages and differences of the more constrained experiment compared to fully interactive model experiments. This way, we advance the process-level understanding of the drivers of SAI-induced atmospheric responses.
Matthew Henry, Ewa M. Bednarz, and Jim Haywood
Atmos. Chem. Phys., 24, 13253–13268, https://doi.org/10.5194/acp-24-13253-2024, https://doi.org/10.5194/acp-24-13253-2024, 2024
Short summary
Short summary
Stratospheric aerosol injection (SAI) refers to a climate intervention by which aerosols are intentionally added to the high atmosphere to increase the amount of reflected sunlight and reduce Earth's temperature. The climate outcomes of SAI depend on the latitude of injection. While injecting aerosols at the Equator has undesirable side effects, injecting away from the Equator has different effects on temperature, rainfall, ozone, and atmospheric circulation, which are analysed in this work.
Yan Zhang, Douglas G. MacMartin, Daniele Visioni, Ewa M. Bednarz, and Ben Kravitz
Earth Syst. Dynam., 15, 191–213, https://doi.org/10.5194/esd-15-191-2024, https://doi.org/10.5194/esd-15-191-2024, 2024
Short summary
Short summary
Injecting SO2 into the lower stratosphere can temporarily reduce global mean temperature and mitigate some risks associated with climate change, but injecting it at different latitudes and seasons would have different impacts. This study introduces new stratospheric aerosol injection (SAI) strategies and explores the importance of the choice of SAI strategy, demonstrating that it notably affects the distribution of aerosol cloud, injection efficiency, and various surface climate impacts.
Ewa M. Bednarz, Ryan Hossaini, and Martyn P. Chipperfield
Atmos. Chem. Phys., 23, 13701–13711, https://doi.org/10.5194/acp-23-13701-2023, https://doi.org/10.5194/acp-23-13701-2023, 2023
Short summary
Short summary
We quantify, for the first time, the time-varying impact of uncontrolled emissions of chlorinated very short-lived substances (Cl-VSLSs) on stratospheric ozone using a state-of-the-art chemistry-climate model. We demonstrate that Cl-VSLSs already have a non-negligible impact on stratospheric ozone, including a local reduction of up to ~7 DU in Arctic ozone in the cold winter of 2019/20, and any so future growth in emissions will continue to offset some of the benefits of the Montreal Protocol.
Ewa M. Bednarz, Amy H. Butler, Daniele Visioni, Yan Zhang, Ben Kravitz, and Douglas G. MacMartin
Atmos. Chem. Phys., 23, 13665–13684, https://doi.org/10.5194/acp-23-13665-2023, https://doi.org/10.5194/acp-23-13665-2023, 2023
Short summary
Short summary
We use a state-of-the-art Earth system model and a set of stratospheric aerosol injection (SAI) strategies to achieve the same level of global mean surface cooling through different combinations of location and/or timing of the injection. We demonstrate that the choice of SAI strategy can lead to contrasting impacts on stratospheric and tropospheric temperatures, circulation, and chemistry (including stratospheric ozone), thereby leading to different impacts on regional surface climate.
Ewa M. Bednarz, Ryan Hossaini, N. Luke Abraham, and Martyn P. Chipperfield
Geosci. Model Dev., 16, 6187–6209, https://doi.org/10.5194/gmd-16-6187-2023, https://doi.org/10.5194/gmd-16-6187-2023, 2023
Short summary
Short summary
Development and performance of the new DEST chemistry scheme of UM–UKCA is described. The scheme extends the standard StratTrop scheme by including important updates to the halogen chemistry, thus allowing process-oriented studies of stratospheric ozone depletion and recovery, including impacts from both controlled long-lived ozone-depleting substances and emerging issues around uncontrolled, very short-lived substances. It will thus aid studies in support of future ozone assessment reports.
Matthew Henry, Jim Haywood, Andy Jones, Mohit Dalvi, Alice Wells, Daniele Visioni, Ewa M. Bednarz, Douglas G. MacMartin, Walker Lee, and Mari R. Tye
Atmos. Chem. Phys., 23, 13369–13385, https://doi.org/10.5194/acp-23-13369-2023, https://doi.org/10.5194/acp-23-13369-2023, 2023
Short summary
Short summary
Solar climate interventions, such as injecting sulfur in the stratosphere, may be used to offset some of the adverse impacts of global warming. We use two independently developed Earth system models to assess the uncertainties around stratospheric sulfur injections. The injection locations and amounts are optimized to maintain the same pattern of surface temperature. While both models show reduced warming, the change in rainfall patterns (even without sulfur injections) is uncertain.
Ewa M. Bednarz, Daniele Visioni, Ben Kravitz, Andy Jones, James M. Haywood, Jadwiga Richter, Douglas G. MacMartin, and Peter Braesicke
Atmos. Chem. Phys., 23, 687–709, https://doi.org/10.5194/acp-23-687-2023, https://doi.org/10.5194/acp-23-687-2023, 2023
Short summary
Short summary
Building on Part 1 of this two-part study, we demonstrate the role of biases in climatological circulation and specific aspects of model microphysics in driving the differences in simulated sulfate distributions amongst three Earth system models. We then characterize the simulated changes in stratospheric and free-tropospheric temperatures, ozone, water vapor, and large-scale circulation, elucidating the role of the above aspects in the surface responses discussed in Part 1.
Daniele Visioni, Ewa M. Bednarz, Walker R. Lee, Ben Kravitz, Andy Jones, Jim M. Haywood, and Douglas G. MacMartin
Atmos. Chem. Phys., 23, 663–685, https://doi.org/10.5194/acp-23-663-2023, https://doi.org/10.5194/acp-23-663-2023, 2023
Short summary
Short summary
The paper constitutes Part 1 of a study performing a first systematic inter-model comparison of the atmospheric responses to stratospheric sulfate aerosol injections (SAIs) at various latitudes as simulated by three state-of-the-art Earth system models. We identify similarities and differences in the modeled aerosol burden, investigate the differences in the aerosol approaches between the models, and ultimately show the differences produced in surface climate, temperature and precipitation.
Simone Tilmes, Daniele Visioni, Andy Jones, James Haywood, Roland Séférian, Pierre Nabat, Olivier Boucher, Ewa Monica Bednarz, and Ulrike Niemeier
Atmos. Chem. Phys., 22, 4557–4579, https://doi.org/10.5194/acp-22-4557-2022, https://doi.org/10.5194/acp-22-4557-2022, 2022
Short summary
Short summary
This study assesses the impacts of climate interventions, using stratospheric sulfate aerosol and solar dimming on stratospheric ozone, based on three Earth system models with interactive stratospheric chemistry. The climate interventions have been applied to a high emission (baseline) scenario in order to reach global surface temperatures of a medium emission scenario. We find significant increases and decreases in total column ozone, depending on regions and seasons.
Xuewei Hou, Ryan Hossaini, Oliver Wild, James Lee, and Ye Wang
EGUsphere, https://doi.org/10.5194/egusphere-2026-5718, https://doi.org/10.5194/egusphere-2026-5718, 2026
This preprint is open for discussion and under review for Geoscientific Model Development (GMD).
Short summary
Short summary
Methane affects both climate and atmospheric chemistry. We compared different ways of representing methane in a global model and found that simulating methane from its emissions better reproduces observed patterns and regional trends. More importantly, it captures the long-term response of methane and atmospheric oxidants to emission changes, which cannot be fully represented when methane concentrations are prescribed.
Isabelle Sangha, Nathan L. Abraham, Andrew Orr, Hua Lu, Michael C. Pitts, Lamont R. Poole, and Michael Weimer
Geosci. Model Dev., 19, 9857–9877, https://doi.org/10.5194/gmd-19-9857-2026, https://doi.org/10.5194/gmd-19-9857-2026, 2026
Short summary
Short summary
The UK Earth System Model is updated with an improved polar stratospheric cloud scheme. The performance of the scheme is evaluated against satellite data. While the model fails to form the full range of observed ice, the scheme improves its ability to represent different polar stratospheric cloud types and their variations. This brings the model closer to satellite observations and highlights the need for further development to capture the polar stratospheric clouds with high number densities.
Florentin Hiault, Emmanuel Mahieu, Pierre-Henri Lefebvre, Martyn P. Chipperfield, Zihao Wang, Martin K. Vollmer, Jeremy J. Harrison, and Diana Roos
EGUsphere, https://doi.org/10.5194/egusphere-2026-5290, https://doi.org/10.5194/egusphere-2026-5290, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
We derived a multi-decadal record of a potent greenhouse gas that is unintentionally released during the production of another industrial chemical. Using infrared measurements collected in the Swiss Alps from 1986 to 2024, we found that the amount of this gas in the atmosphere continued to increase despite efforts to reduce emissions. Comparisons with independent measurements confirmed the reliability of the method and the need for continued long-term monitoring.
Sean M. Davis, William T. Ball, Yue Jia, Gabriel Chiodo, Justin A. Alsing, James Keeble, Hideharu Akiyoshi, Carlo Arosio, Ewa M. Bednarz, Andreas Chrysanthou, Melanie Coldewey-Egbers, Robert Damadeo, Sandip Dhomse, Mohamadou A. Diallo, Simone Dietmuller, Roland Eichinger, Stacey Frith, Birgit Hassler, Michaela I. Hegglin, Daan Hubert, Patrick Jöckel, Béatrice Josse, Natalya Kramarova, Diego Loyola, Eliane Maillard Barras, Marion Marchand, Olaf Morgenstern, David Plummer, Robert W. Portmann, Karen H. Rosenlof, Alexei Rozanov, Viktoria F. Sofieva, Johannes Staehelin, Timofei Sukhodolov, Kleareti Tourpali, Ronald J. Van der A, H. J. Ray Wang, Krzysztof Wargan, Shingo Watanabe, Mark Weber, Jeannette D. Wild, Yousuke Yamashita, and Jerry Ziemke
Atmos. Chem. Phys., 26, 13817–13843, https://doi.org/10.5194/acp-26-13817-2026, https://doi.org/10.5194/acp-26-13817-2026, 2026
Short summary
Short summary
This study investigates tropical ozone changes in models and satellite observations to determine how well they agree and whether observations can constrain model projections. At some levels, satellite records disagree significantly on the magnitude of ozone changes. While early and late 21st century trends are correlated across models, suggesting a potential emergent constraint, the spread in observations means they are unable to provide guidance on the credibility of model projections.
Xuewei Hou, Ryan Hossaini, Oliver Wild, Andrea Mazzeo, Richard J. Pope, Ye Wang, Siyuan Wang, Yuanhong Zhao, James Lee, Bin Zhu, Tianliang Zhao, and Alok K. Pandey
Atmos. Chem. Phys., 26, 13767–13793, https://doi.org/10.5194/acp-26-13767-2026, https://doi.org/10.5194/acp-26-13767-2026, 2026
Short summary
Short summary
The atmosphere’s ability to remove pollutants and greenhouse gases is largely controlled by the hydroxyl radical, but the causes of its long-term changes remain uncertain. Using a global atmospheric model, we quantified the effects of emissions, weather, and key chemical processes on hydroxyl radical levels between 2000 and 2017. Our findings improve understanding of atmospheric self-cleansing and help reduce uncertainties in future climate assessments.
Ye Wang, Oliver Wild, Xuewei Hou, and Ryan Hossaini
EGUsphere, https://doi.org/10.5194/egusphere-2026-5371, https://doi.org/10.5194/egusphere-2026-5371, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
This study provides an assessment of the overall uncertainty in H2 soil deposition velocity from major soil parameters, quantifies the contribution of the soil sink to interannual variation in tropospheric H2 abundance, and projects the future H2 soil uptake from 2015 to 2100. This study demonstrated the major contribution of the soil sink to the interannual variability in H2 abundance, highlighted the importance of soil moisture in governing current and future soil sink.
Martin B. Andrews, Neal Butchart, James A. Anstey, Ewa Bednarz, Dillon Elsbury, Jorge L. García-Franco, Vinay Kumar, Froila M. Palmeiro, Natasha E. Trencham, Kohei Yoshida, Zhaoyang Chai, Dong-Chan Hong, Kai Huang, Aleena M. Jaison, Yoshio Kawatani, Jeff R. Knight, Pu Lin, François Lott, Yixiong Lu, Hiroaki Naoe, Scott M. Osprey, Jadwiga H. Richter, Federico Serva, Seok-Woo Son, Qi Tang, Shingo Watanabe, and Jinbo Xie
Weather Clim. Dynam., 7, 1797–1820, https://doi.org/10.5194/wcd-7-1797-2026, https://doi.org/10.5194/wcd-7-1797-2026, 2026
Short summary
Short summary
The observed winds in the upper atmosphere over the equator have alternating easterly and westerly regions that descend towards the lower atmosphere before dissipating, with a period of approximately 28 months. This is known as the Quasi-Biennial Oscillation (QBO). The QBO is known to influence remote regions of the atmosphere. This paper details the results of multi-model experiments where the QBO is nudged towards the observed QBO allowing the assessment of these remote connections.
Antonio G. Bruno, David P. Moore, Jeremy J. Harrison, Ailish Graham, Martyn P. Chipperfield, and Corinne Vigouroux
Atmos. Chem. Phys., 26, 12925–12952, https://doi.org/10.5194/acp-26-12925-2026, https://doi.org/10.5194/acp-26-12925-2026, 2026
Short summary
Short summary
Indonesian peatlands store vast carbon reserves, but can release large quantities of greenhouse gases and other species with significant environmental impacts, including hydrogen cyanide (HCN), when fires occur. Analyzing three major El Niño years with satellites and models, we found that emissions depend on local hydrological conditions, not just El Niño strength. Including soil moisture and burn depth can improve emission estimates and climate strategies.
Daniele Visioni, Alan Robock, Alistair Duffey, Matthew Henry, Haruki Hirasawa, Walker Raymond Lee, Cindy Wang, Kelsey Roberts, Shingo Watanabe, Michelle Simões Reboita, Masahiro Sugiyama, Ben Kravitz, Jim Haywood, Simone Tilmes, Frédéric K. Bonou, Jack Chen, Timofei Sukhodolov, Sandro Vattioni, Andrin Jörimann, Diego Villanueva, Ryan Vella, Paul Farron, Ewa Bednarz, Ulrike Niemeier, Colleen Golja, and Juan A. Añel
Geosci. Model Dev., 19, 8469–8499, https://doi.org/10.5194/gmd-19-8469-2026, https://doi.org/10.5194/gmd-19-8469-2026, 2026
Short summary
Short summary
The Geoengineering Model Intercomparison Project is a coordinated international model intercomparison effort aiming to provide robust experimental protocols for simulations of various Solar Radiation Modification (SRM) methods. In this manuscript, we describe a list of novel experiments decided by the community, to be run by climate models to better understand sources of uncertainty in SRM. We also show and discuss some preliminary results from a few climate models.
Ewa M. Bednarz, Amy H. Butler, James M. Haywood, Matthew Henry, Andy Jones, Ben Kravitz, Walker R. Lee, Douglas G. MacMartin, Amanda C. Maycock, Takashi Sekiya, Shingo Watanabe, and Daniele Visioni
Atmos. Chem. Phys., 26, 12751–12770, https://doi.org/10.5194/acp-26-12751-2026, https://doi.org/10.5194/acp-26-12751-2026, 2026
Short summary
Short summary
An assessment of the potential impacts of Stratospheric Aerosol Injection, a proposed method to offset global warming, on stratospheric ozone projections over the 21st century using the new multi-model GeoMIP (Geoengineering Model Intercomparison Project) G6-1.5K-SAI (Stratospheric Aerosol Injection) experiment. We discuss drivers of the responses, identify areas of model agreement and disagreement and sources of uncertainty. Our results highlight the need to assess any projected SAI impacts in wider strategy and scenario dimension using a multi-model framework.
Sandip S. Dhomse and Martyn P. Chipperfield
Earth Syst. Sci. Data, 18, 6171–6189, https://doi.org/10.5194/essd-18-6171-2026, https://doi.org/10.5194/essd-18-6171-2026, 2026
Short summary
Short summary
We have developed an innovative methodology that uses machine learning to
correcterrors in chemical models by using satellite data as a guide. In this latest update, we detail improvements to our process for creating a gap-free data of two major ozone-depleting substances: CFC-11 and CFC-12. By combining the strengths of both chemical models and satellites, we have produced a reliable, global dataset that allows researchers to track long-term trends and better evaluate the chemical models.
Walker Raymond Lee, Simone Tilmes, and Ewa M. Bednarz
Earth Syst. Dynam., 17, 1117–1134, https://doi.org/10.5194/esd-17-1117-2026, https://doi.org/10.5194/esd-17-1117-2026, 2026
Short summary
Short summary
We present climate model simulation of stratospheric aerosol injection, a proposed method of climate intervention where reflective particles are placed in the stratosphere to cool the planet. We design our simulated interventions to maintain certain surface temperature patterns, and show that the same temperatures can be maintained in different ways because of how the ocean transports heat. This has implications for how climate intervention model experiments are designed in the future.
Ewa M. Bednarz, Valentina Aquila, Amy H. Butler, Peter Colarco, Eric Fleming, Freja F. Østerstrøm, David Plummer, Ilaria Quaglia, William Randel, Michelle L. Santee, Takashi Sekiya, Simone Tilmes, Xinyue Wang, Shingo Watanabe, Wandi Yu, Jun Zhang, Yunqian Zhu, and Zhihong Zhuo
Atmos. Chem. Phys., 26, 11355–11370, https://doi.org/10.5194/acp-26-11355-2026, https://doi.org/10.5194/acp-26-11355-2026, 2026
Short summary
Short summary
The 2022 Hunga eruption injected unprecedented quantities of water vapor into the stratosphere, alongside modest amounts of aerosol precursors. We assess its impacts on stratospheric ozone layer using a multi-model ensemble of chemistry-climate simulations. The results confirm the eruption's role in modulating SH (Southern Hemisphere) mid and high latitudes ozone abundances in the short term, and discuss the different chemical and dynamical processes driving those changes as well as the role of natural variability.
Andrin Jörimann, Timofei Sukhodolov, Simone Tilmes, David Plummer, Shingo Watanabe, Hideharu Akiyoshi, Gabriel Chiodo, Daniele Visioni, Sandro Vattioni, Eugene Rozanov, Ewa Monika Bednarz, Béatrice Josse, Yousuke Yamashita, and Thomas Peter
Atmos. Chem. Phys., 26, 11207–11234, https://doi.org/10.5194/acp-26-11207-2026, https://doi.org/10.5194/acp-26-11207-2026, 2026
Short summary
Short summary
We study a future scenario where artificial stratospheric aerosol injections counter medium climate change, to understand possible negative side effects like ozone depletion. The injected aerosol layer is implemented uniformly in five climate models, which eliminates some uncertainty from model-specific aerosol evolution. The models agree well on where and how key thermodynamical (heating, circulation) and chemical processes change, however, the strength of the changes varies considerably.
Lucy Hart, Ryan Hossaini, Oliver Wild, Crispin Halsall, Martin K. Vollmer, and David Sherry
EGUsphere, https://doi.org/10.5194/egusphere-2026-4613, https://doi.org/10.5194/egusphere-2026-4613, 2026
Short summary
Short summary
HFO-1234yf is increasingly used in cars because of its low climate impact but once emitted to the atmosphere it forms trifluoroacetic acid (TFA), a chemical that remains on Earth permanently. We present the first global emission inventory of HFO-1234yf from cars and compare our results to atmospheric measurements. Using an atmospheric chemistry model, we found that TFA produced from this source is rapidly growing and most TFA is deposited outside of the region HFO-1234yf was emitted.
Colleen Marie Golja, Marianna Linz, Ewa Monika Bednarz, Daniele Visioni, Ben Kravitz, John A. Dykema, Michelle E. Frazer, Anthony C. Jones, Isla R. Simpson, and Shingo Watanabe
EGUsphere, https://doi.org/10.5194/egusphere-2026-4200, https://doi.org/10.5194/egusphere-2026-4200, 2026
Short summary
Short summary
Adding reflective particles to the stratosphere has been proposed to cool the planet, but how the resulting lower-stratospheric heating affects the broader climate remains unclear. This study simulates idealized lower-stratospheric heating across five climate models finding large inter-model differences in the stratospheric and surface response. The results highlight ways in which these differences may be explained by biases in the stratospheric climatological mean state.
Haotian He, Shujie Chang, Martyn P. Chipperfield, Sandip S. Dhomse, Wuhu Feng, Saffron G. Heddell, Yajuan Li, and Mark Weber
Atmos. Chem. Phys., 26, 9741–9756, https://doi.org/10.5194/acp-26-9741-2026, https://doi.org/10.5194/acp-26-9741-2026, 2026
Short summary
Short summary
Overall, in the long-term, Antarctic ozone evolution reflects the interplay of multiple processes, with dynamical drivers holding a particularly strong influence on recovery patterns. The Brewer-Dobson circulation perturbations play a significant role in the long-term ozone trend, requiring more research and continued attention to the ozone hole and dynamic processes to improve our understanding of long-term ozone variability and predict future changes in the Antarctic ozone hole.
Laura Gómez-Martín, Cristina Prados-Roman, Martyn P. Chipperfield, Michel Van Roozendael, Olga Puentedura, Monica Navarro-Comas, Hector Ochoa, and Margarita Yela
Atmos. Meas. Tech., 19, 4393–4413, https://doi.org/10.5194/amt-19-4393-2026, https://doi.org/10.5194/amt-19-4393-2026, 2026
Short summary
Short summary
The Antarctic ozone hole remains a critical global challenge. Accurately measuring the gases that cause it during twilights is difficult due to rapid chemical changes. We used advanced computer simulations to reproduce observations at 2 Antarctic stations to account for these fluctuations and the Earth's curvature. Our results improve the accuracy of atmospheric monitoring, helping scientists better track the recovery of the ozone layer and understand the complex chemistry driving its depletion.
Saffron Genise Heddell, Martyn P. Chipperfield, Graham W. Mann, Sandip S. Dhomse, Wuhu Feng, Xin Zhou, Masaru Yoshioka, and Anthony Jones
EGUsphere, https://doi.org/10.5194/egusphere-2026-3619, https://doi.org/10.5194/egusphere-2026-3619, 2026
Short summary
Short summary
The 2022 Hunga eruption injected extraordinary amounts of water vapour into the stratosphere. Using a global model, we find a 7 % chemical increase in 2023 Antarctic ozone hole area, a modest increase limited by the cold Antarctic temperatures causing efficient removal of the Hunga water by polar stratospheric clouds. The impact on ozone was larger in the warmer, more sunlit vortex edge region. We highlight the value of natural events as test-cases for potential changes in the stratosphere.
Evgenia Galytska, Birgit Hassler, Carlo Arosio, Martyn P. Chipperfield, Sandip S. Dhomse, Kimberlee Dubé, Wuhu Feng, Fernando Iglesias-Suarez, and Jakob Runge
Atmos. Chem. Phys., 26, 8185–8209, https://doi.org/10.5194/acp-26-8185-2026, https://doi.org/10.5194/acp-26-8185-2026, 2026
Short summary
Short summary
We explore how chemical and dynamical processes shape ozone in the tropical middle stratosphere using satellite data and a chemistry-transport model. We apply a framework to identify cause–effect relationships and estimate their strength. For 2004-2021 monthly data, we detect an indirect pathway controlling ozone variability, with effects increasing after two–three months. We further assess how different wind regimes influence this pathway.
Ilaria Quaglia, Daniele Visioni, Ewa M. Bednarz, Yunqian Zhu, Georgiy Stenchikov, Valentina Aquila, Cheng-Cheng Liu, Graham W. Mann, Yifeng Peng, Takashi Sekiya, Simone Tilmes, Xinyue Wang, Shingo Watanabe, Pengfei Yu, Jun Zhang, Wandi Yu, and Zhihong Zhuo
Atmos. Chem. Phys., 26, 7677–7704, https://doi.org/10.5194/acp-26-7677-2026, https://doi.org/10.5194/acp-26-7677-2026, 2026
Short summary
Short summary
On January 15, 2022, the Hunga volcano eruption released unprecedented amounts of water vapor into the atmosphere alongside a modest amount of SO2. In this work we analyse results from multiple Earth system models. The models agree that the eruption led to small negative radiative forcing from sulfate aerosols and that the contribution from water vapor was minimal. Therefore, the Hunga eruption cannot explain the exceptional surface warming observed in 2023.
Walker Raymond Lee, Daniele Visioni, Benjamin Moore Wagman, Christopher Robert Wentland, Ben Kravitz, Shingo Watanabe, Takashi Sekiya, Andy Jones, Jim Haywood, Matthew Henry, and Ewa Monika Bednarz
Atmos. Chem. Phys., 26, 7463–7483, https://doi.org/10.5194/acp-26-7463-2026, https://doi.org/10.5194/acp-26-7463-2026, 2026
Short summary
Short summary
Stratospheric aerosol injection (SAI) is a proposed method of cooling the planet by introducing reflective particles called aerosols into the middle atmosphere to reflect sunlight back into space. We consider recent simulations of SAI from four different climate models. SAI cools the planet effectively in all four models; we examine the impacts on temperature and precipitation in each model and compare to previous experiments. Our simulations will help inform future research and policy.
Martin R. Willett, Melissa E. Brooks, Andrew Bushell, Paul Earnshaw, Charline Marzin, Samantha Smith, Lorenzo Tomassini, Nathan Luke Abraham, Martin Best, John M. Edwards, Kalli Furtado, Catherine Hardacre, Alan J. Hewitt, Ben Johnson, Adrian Lock, Jane P. Mulcahy, James Manners, Alistair Sellar, Peter Sheridan, Warren Tennant, Kwinten Van Weverberg, Vidya Varma, and Michael Whitall
EGUsphere, https://doi.org/10.5194/egusphere-2026-2425, https://doi.org/10.5194/egusphere-2026-2425, 2026
Short summary
Short summary
Global Atmosphere and Land (GAL) configurations of the Unified Model (UM) and JULES are developed for use in any global atmospheric modelling application. We describe the latest version, GAL9. We compare GAL9 with its predecessor and show that it gives improved forecasts of weather and climate. GAL9 has been used for weather forecasts in the UK from early 2026 and it will be used to study the Earth's climate.
Man Mei Chim, Nathan Luke Abraham, Thomas J. Aubry, Ben Johnson, Hella Garny, Susan Solomon, and Anja Schmidt
Atmos. Chem. Phys., 26, 6781–6797, https://doi.org/10.5194/acp-26-6781-2026, https://doi.org/10.5194/acp-26-6781-2026, 2026
Short summary
Short summary
Sulfate aerosols from explosive eruptions can provide surfaces for chemical reactions destroying ozone. Assessing the effects of volcanic sulfate aerosols is crucial for understanding future ozone recovery. We find sporadic eruptions can induce a small delay in stratospheric ozone recovery by a few years over Antarctica and Southern Hemisphere mid-latitudes. Our results highlight the importance to continuously monitor atmospheric composition and processes to understand changes in ozone recovery.
Marta Abalos, Thomas Birner, Andreas Chrysanthou, Sean Davis, Alvaro de la Cámara, Sandip Dhomse, Hella Garny, Michaela I. Hegglin, Daan Hubert, Oksana Ivaniha, James Keeble, Marianna Linz, Daniele Minganti, Jessica Neu, David Plummer, Laura Saunders, Kasturi Shah, Gabriele Stiller, Kleareti Tourpali, Darryn Waugh, Nathan Luke Abraham, Hideharu Akiyoshi, Martyn P. Chipperfield, Patrick Jöckel, Béatrice Josse, Marion Marchand, Patrick Martineau, Olaf Morgenstern, Timofei Sukhodolov, Shingo Watanabe, and Yousuke Yamashita
Atmos. Chem. Phys., 26, 5249–5291, https://doi.org/10.5194/acp-26-5249-2026, https://doi.org/10.5194/acp-26-5249-2026, 2026
Short summary
Short summary
Accurate representation of stratospheric transport in Chemistry-Climate Models is essential for reliable climate projections. This study evaluates three generations of models using observational data and reanalyses, identifying persistent biases and their potential causes. Some biases persist or even worsen in newer models. These findings highlight key limitations and inform efforts to improve models and advance understanding through process-based studies and enhanced observations.
Xu-Cheng He, Nathan Luke Abraham, Han Ding, Maria R. Russo, Daniel P. Grosvenor, Yao Ge, Xuemei Wang, Anthony C. Jones, Pedro Campuzano-Jost, Benjamin Nault, Agnieszka Kupc, Donald Blake, Jose L. Jimenez, Christina J. Williamson, James Weber, Alexander T. Archibald, and Hamish Gordon
Atmos. Chem. Phys., 26, 3805–3851, https://doi.org/10.5194/acp-26-3805-2026, https://doi.org/10.5194/acp-26-3805-2026, 2026
Short summary
Short summary
Aerosols affect clouds and climate. However, current climate models still struggle to simulate them accurately. We used aircraft data from a global mission to evaluate how well the UK Earth System Model represents aerosols and their precursors. Our results show that the model misses key formation processes in clean ocean regions, suggesting that future improvements should focus on better representing how aerosols form naturally in the atmosphere.
Yuwen Li, Wuhu Feng, John M. C. Plane, Tijian Wang, and Martyn P. Chipperfield
Atmos. Chem. Phys., 26, 3621–3635, https://doi.org/10.5194/acp-26-3621-2026, https://doi.org/10.5194/acp-26-3621-2026, 2026
Short summary
Short summary
The space industry is growing rapidly, but its environmental effects remain uncertain. We used a global chemistry-climate model to study how chlorine released by rocket launches could affect the ozone layer and its recovery from past depletion. Even with large growth in launches, global ozone loss remains small but could locally slow the healing of the ozone layer. These findings highlight the need to consider rocket emissions in future environmental policies.
Jared Farley, Douglas G. MacMartin, Daniele Visioni, Ben Kravitz, Ewa M. Bednarz, Alistair Duffey, Matthew Henry, and Ali Akherati
Geosci. Model Dev., 19, 1809–1831, https://doi.org/10.5194/gmd-19-1809-2026, https://doi.org/10.5194/gmd-19-1809-2026, 2026
Short summary
Short summary
As the climate changes, many are studying sunlight reflection as a potential method of cooling. Such climate intervention could be deployed in many possible ways, including in scenarios where not every actor agrees on the strategy of cooling. These scenarios are so diverse that to explore all of them using earth system models proves to be too costly. In this paper, we develop a simplified climate model that allows users to easily explore climate intervention scenarios of their choice.
Megan A. J. Brown, Nicola J. Warwick, Nathan Luke Abraham, Paul T. Griffiths, Steve T. Rumbold, Gerd A. Folberth, Fiona M. O'Connor, Hannah Bryant, and Alex T. Archibald
Geosci. Model Dev., 19, 1537–1557, https://doi.org/10.5194/gmd-19-1537-2026, https://doi.org/10.5194/gmd-19-1537-2026, 2026
Short summary
Short summary
Hydrogen (H2) is an indirect greenhouse gas by increasing methane (CH4) lifetime. Interaction between H2 and CH4 is important for hydrogen’s global warming potential (GWP). Global models do not represent this interaction well; H2 or CH4 are prescribed at the surface. We implement an interactive H2 scheme into a global model coupled with interactive CH4. We simulate scenarios demonstrating its capability, improving model performance and more accurately representing H2-CH4 interaction.
Maria P. Velásquez-García, Richard J. Pope, Steven T. Turnock, Chetan Deva, David P. Moore, Guilherme Mataveli, Steve R. Arnold, Ruth M. Doherty, and Martyn P. Chipperfield
Biogeosciences, 23, 1341–1364, https://doi.org/10.5194/bg-23-1341-2026, https://doi.org/10.5194/bg-23-1341-2026, 2026
Short summary
Short summary
Incorporating fire simulation into climate models is crucial for accurately representing interactions between fires, ecosystems, and climate, thereby enhancing climate projections. In South America, the INFERNO (Interactive Fires and Emissions algorithm for Natural Environments) fire model broadly captures CO emissions in active fire zones, e.g., the Amazon Arc of Deforestation. Still, it tends to overestimate emissions in tree-rich ecosystems, where INFERNO is too sensitive to low soil moisture, and to underestimate emissions in less tree-abundant ecosystems.
Cindy Wang, Daniele Visioni, Glen Chua, and Ewa M. Bednarz
Atmos. Chem. Phys., 26, 1339–1357, https://doi.org/10.5194/acp-26-1339-2026, https://doi.org/10.5194/acp-26-1339-2026, 2026
Short summary
Short summary
Stratospheric aerosol injection is a proposed method to slow global warming by adding tiny reflective particles high up in the atmosphere to cool the planet. We study how this proposed method might affect air quality and human health using climate models. We find that the health impacts would likely be small and are mainly driven by changes in climate, not by the particles themselves.
Clara Orbe, Alison Ming, Gabriel Chiodo, Michael Prather, Mohamadou Diallo, Qi Tang, Andreas Chrysanthou, Hiroaki Naoe, Xin Zhou, Irina Thaler, Dillon Elsbury, Ewa Bednarz, Jonathon S. Wright, Aaron Match, Shingo Watanabe, James Anstey, Tobias Kerzenmacher, Stefan Versick, Marion Marchand, Feng Li, and James Keeble
Geosci. Model Dev., 19, 773–794, https://doi.org/10.5194/gmd-19-773-2026, https://doi.org/10.5194/gmd-19-773-2026, 2026
Short summary
Short summary
The quasi-biennial oscillation (QBO) is the main source of wind fluctuations in the tropical stratosphere, which can couple to surface climate. However, models do a poor job of simulating the QBO in the lower stratosphere, for reasons that remain unclear. One possibility is that models do not completely represent how ozone influences the QBO-associated wind variations. Here we propose a multi-model framework for assessing how ozone influences the QBO in recent past and future climates.
William J. Collins, John S. Daniel, Martyn P. Chipperfield, Martin Cussac, Makoto Deushi, Gregory Faluvegi, Paul Griffiths, Øivind Hodnebrog, Larry W. Horowitz, James Keeble, Douglas Kinnison, Vaishali Naik, Fiona M. O'Connor, Drew Shindell, Simone Tilmes, Kostas Tsigaridis, Zihao Wang, and James Weber
EGUsphere, https://doi.org/10.5194/egusphere-2025-6033, https://doi.org/10.5194/egusphere-2025-6033, 2026
Short summary
Short summary
Ozone depleting substances (ODSs) are also greenhouse gases that cause global warming. However, their destruction of ozone contributes a global cooling. We have used results from climate models that include atmospheric chemistry and found that the cooling effect of the ozone depletion diagnosed in the models was larger than that calculated using a standard method. We find that some ODSs have a net cooling effect whereas for others the warming effect is significantly reduced.
Ewa M. Bednarz, Amy H. Butler, Xinyue Wang, Zhihong Zhuo, Wandi Yu, Georgiy Stenchikov, Matthew Toohey, and Yunqian Zhu
Atmos. Chem. Phys., 26, 197–215, https://doi.org/10.5194/acp-26-197-2026, https://doi.org/10.5194/acp-26-197-2026, 2026
Short summary
Short summary
We investigate whether the 2022 Hunga eruption could affect surface climate via indirect pathways using large ensembles of Earth System Model simulations. These suggest that the eruption could have a non-negligible influence on regional surface climate, and we discuss the mechanisms via which such an influence could occur but also highlight that the forcing is relatively weak compared to natural climate variability which significantly hinders the detection of such impacts in the real world.
Douwang Li, Zhe Wang, Siyi Zhao, Jiankai Zhang, Wuhu Feng, and Martyn P. Chipperfield
Atmos. Chem. Phys., 26, 77–94, https://doi.org/10.5194/acp-26-77-2026, https://doi.org/10.5194/acp-26-77-2026, 2026
Short summary
Short summary
We find that wind variations at the equator (QBO) modulate the occurrence of Arctic polar stratospheric clouds (PSCs), which are key contributors to ozone depletion. During westerly QBO, the PSC occurrence is significantly greater than during easterly QBO. The QBO affects PSC mainly through temperature, while H2O and HNO3 have less effect. This suggests that future climate change may affect ozone recovery if it alters the QBO pattern. This study provides a new perspective on ozone prediction.
Michael P. Cartwright, Jeremy J. Harrison, David P. Moore, Richard J. Pope, Martyn P. Chipperfield, Chris Wilson, and Wuhu Feng
Atmos. Chem. Phys., 25, 15913–15934, https://doi.org/10.5194/acp-25-15913-2025, https://doi.org/10.5194/acp-25-15913-2025, 2025
Short summary
Short summary
We use satellite measurements to estimate quantities of a gas called carbonyl sulfide (OCS) in the atmosphere. OCS is consumed during photosynthesis, much like carbon dioxide (CO2). Our data is focused mostly over the global oceans for the year 2018, and we find it compares well with past satellite observations, ground-based measurements and modelled OCS. We hope to extend this measurement record and use it in data-driven tools in the future to better understand the carbon cycle globally.
Matilda A. Pimlott, Richard J. Pope, Brian J. Kerridge, Richard Siddans, Barry G. Latter, Wuhu Feng, and Martyn P. Chipperfield
Atmos. Chem. Phys., 25, 15991–16007, https://doi.org/10.5194/acp-25-15991-2025, https://doi.org/10.5194/acp-25-15991-2025, 2025
Short summary
Short summary
Tropospheric ozone (O3) is a harmful secondary atmospheric pollutant and an important greenhouse gas. Here, we present an in-depth analysis of lower-tropospheric sub-column O3 (LTCO3, surface – 6 km) records from three satellite products produced by the Rutherford Appleton Laboratory (RAL) over Europe between 1996 and 2017. Overall, we detect moderate negative trends in the satellite records, but corresponding model simulations and ozonesonde measurements show negligible trends.
Zhihong Zhuo, Xinyue Wang, Yunqian Zhu, Wandi Yu, Ewa M. Bednarz, Eric Fleming, Peter R. Colarco, Shingo Watanabe, David Plummer, Georgiy Stenchikov, William Randel, Adam Bourassa, Valentina Aquila, Takashi Sekiya, Mark R. Schoeberl, Simone Tilmes, Jun Zhang, Paul J. Kushner, and Francesco S. R. Pausata
Atmos. Chem. Phys., 25, 13161–13176, https://doi.org/10.5194/acp-25-13161-2025, https://doi.org/10.5194/acp-25-13161-2025, 2025
Short summary
Short summary
The 2022 Hunga eruption caused unprecedented stratospheric water injection, triggering unique atmospheric impacts. This study combines observations and model simulations, projecting a stratospheric water vapor anomaly lasting 4–7 years, with significant temperature variations and ozone depletion in the upper atmosphere lasting 7–10 years. These findings offer critical insights into the role of stratospheric water vapor in shaping climate and atmospheric chemistry.
Yunqian Zhu, Hideharu Akiyoshi, Valentina Aquila, Elizabeth Asher, Ewa M. Bednarz, Slimane Bekki, Christoph Brühl, Amy H. Butler, Parker Case, Simon Chabrillat, Gabriel Chiodo, Margot Clyne, Peter R. Colarco, Sandip Dhomse, Lola Falletti, Eric Fleming, Ben Johnson, Andrin Jörimann, Mahesh Kovilakam, Gerbrand Koren, Ales Kuchar, Nicolas Lebas, Qing Liang, Cheng-Cheng Liu, Graham Mann, Michael Manyin, Marion Marchand, Olaf Morgenstern, Paul Newman, Luke D. Oman, Freja F. Østerstrøm, Yifeng Peng, David Plummer, Ilaria Quaglia, William Randel, Samuel Rémy, Takashi Sekiya, Stephen Steenrod, Timofei Sukhodolov, Simone Tilmes, Kostas Tsigaridis, Rei Ueyama, Daniele Visioni, Xinyue Wang, Shingo Watanabe, Yousuke Yamashita, Pengfei Yu, Wandi Yu, Jun Zhang, and Zhihong Zhuo
Geosci. Model Dev., 18, 5487–5512, https://doi.org/10.5194/gmd-18-5487-2025, https://doi.org/10.5194/gmd-18-5487-2025, 2025
Short summary
Short summary
To understand the climate impact of the 2022 Hunga volcanic eruption, we developed a climate model–observation comparison project. The paper describes the protocols and models that participate in the experiments. We designed several experiments to achieve our goals of this activity: (1) to evaluate the climate model performance and (2) to understand the Earth system responses to this eruption.
William J. Collins, Fiona M. O'Connor, Rachael E. Byrom, Øivind Hodnebrog, Patrick Jöckel, Mariano Mertens, Gunnar Myhre, Matthias Nützel, Dirk Olivié, Ragnhild Bieltvedt Skeie, Laura Stecher, Larry W. Horowitz, Vaishali Naik, Gregory Faluvegi, Ulas Im, Lee T. Murray, Drew Shindell, Kostas Tsigaridis, Nathan Luke Abraham, and James Keeble
Atmos. Chem. Phys., 25, 9031–9060, https://doi.org/10.5194/acp-25-9031-2025, https://doi.org/10.5194/acp-25-9031-2025, 2025
Short summary
Short summary
We used 7 climate models that include atmospheric chemistry and find that in a scenario with weak controls on air quality, the warming effects (over 2015 to 2050) of decreases in ozone-depleting substances and increases in air quality pollutants are approximately equal and would make ozone the second highest contributor to warming over this period. We find that for stratospheric ozone recovery, the standard measure of climate effects underestimates a more comprehensive measure.
Ezra Brody, Yan Zhang, Douglas G. MacMartin, Daniele Visioni, Ben Kravitz, and Ewa M. Bednarz
Earth Syst. Dynam., 16, 1325–1341, https://doi.org/10.5194/esd-16-1325-2025, https://doi.org/10.5194/esd-16-1325-2025, 2025
Short summary
Short summary
Stratospheric aerosol injection (SAI) is being studied as a possible supplement to emission reduction to temporarily mitigate some of the risks associated with climate change. The latitudes at which SAI is done determine the effect on the climate. We try to find if there are combinations of latitudes that do a better job of counteracting climate change than existing strategies. We found that there are, but just how significant these improvements are depends on the amount of cooling.
Simone Tilmes, Ewa M. Bednarz, Andrin Jörimann, Daniele Visioni, Douglas E. Kinnison, Gabriel Chiodo, and David Plummer
Atmos. Chem. Phys., 25, 6001–6023, https://doi.org/10.5194/acp-25-6001-2025, https://doi.org/10.5194/acp-25-6001-2025, 2025
Short summary
Short summary
In this paper, we describe the details of a new multi-model intercomparison experiment to assess the effects of Stratospheric Aerosol Intervention (SAI) on stratospheric chemistry and dynamics and, therefore, ozone. Second, we discuss the advantages and differences of the more constrained experiment compared to fully interactive model experiments. This way, we advance the process-level understanding of the drivers of SAI-induced atmospheric responses.
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.
Matilda A. Pimlott, Richard J. Pope, Brian J. Kerridge, Richard Siddans, Barry G. Latter, Lucy J. Ventress, Wuhu Feng, and Martyn P. Chipperfield
Atmos. Chem. Phys., 25, 4391–4401, https://doi.org/10.5194/acp-25-4391-2025, https://doi.org/10.5194/acp-25-4391-2025, 2025
Short summary
Short summary
Globally, lockdowns were implemented to limit the spread of COVID-19, leading to a decrease in emissions of key air pollutants. Here, we use novel satellite data and a chemistry model to investigate the impact of the pandemic on tropospheric ozone (O3), a key pollutant, in 2020. Overall, we found substantial decreases of up to 20 %, two-thirds of which came from emission reductions, while one-third was due to a decrease in the stratospheric O3 flux into the troposphere.
Lena Feld, Pablo Schmid, Marios Mermigkas, Dimitrios Balis, Jochen Gross, Darko Dubravica, Carlos Alberti, Benedikt Herkommer, Stefan Versick, Roland Ruhnke, Frank Hase, and Peter Braesicke
EGUsphere, https://doi.org/10.5194/egusphere-2025-639, https://doi.org/10.5194/egusphere-2025-639, 2025
Short summary
Short summary
Our goal is to measure CO2 emissions from cities, to verify and improve our knowledge of reported anthropogenic emissions. We use atmospheric measurements and simulations of CO2 transport to find an independent estimate. This study investigates the CO2 emissions of the city of Thessaloniki, where the reported emissions differ. The data we collected indicates that the emissions are larger than stated by the ODIAC inventory, which we used for our simulations.
Jamal Makkor, Mathias Palm, Matthias Buschmann, Emmanuel Mahieu, Martyn P. Chipperfield, and Justus Notholt
Atmos. Meas. Tech., 18, 1105–1114, https://doi.org/10.5194/amt-18-1105-2025, https://doi.org/10.5194/amt-18-1105-2025, 2025
Short summary
Short summary
During the years 1950 and 1951, Marcel Migeotte took regular solar measurements in the form of paper rolls at the Jungfraujoch site. These historical spectra proved to be valuable for atmospheric research and needed to be saved for posterity. Therefore, a digitization method which used image-processing techniques was developed to extract them from the historical paper rolls. This allowed them to be saved in a machine-readable format that is easily accessible to the scientific community.
Tatiana Klimiuk, Patrick Ludwig, Antonio Sanchez-Benitez, Helge F. Goessling, Peter Braesicke, and Joaquim G. Pinto
Earth Syst. Dynam., 16, 239–255, https://doi.org/10.5194/esd-16-239-2025, https://doi.org/10.5194/esd-16-239-2025, 2025
Short summary
Short summary
Our study examines potential changes in heatwaves in central Europe due to global warming, using the 2019 summer heatwave as an example. By producing high-resolution storylines, we provide insights into how future heatwaves might spread, how they might persist for longer, and where stronger or weaker temperature increases may occur. This research helps us understand regional thermodynamic responses and highlights the importance of local strategies to protect communities from future heat events.
Lauren R. Marshall, Anja Schmidt, Andrew P. Schurer, Nathan Luke Abraham, Lucie J. Lücke, Rob Wilson, Kevin J. Anchukaitis, Gabriele C. Hegerl, Ben Johnson, Bette L. Otto-Bliesner, Esther C. Brady, Myriam Khodri, and Kohei Yoshida
Clim. Past, 21, 161–184, https://doi.org/10.5194/cp-21-161-2025, https://doi.org/10.5194/cp-21-161-2025, 2025
Short summary
Short summary
Large volcanic eruptions have caused temperature deviations over the past 1000 years; however, climate model results and reconstructions of surface cooling using tree rings do not match. We explore this mismatch using the latest models and find a better match to tree-ring reconstructions for some eruptions. Our results show that the way in which eruptions are simulated in models matters for the comparison to tree-rings, particularly regarding the spatial spread of volcanic aerosol.
Alex T. Archibald, Bablu Sinha, Maria R. Russo, Emily Matthews, Freya A. Squires, N. Luke Abraham, Stephane J.-B. Bauguitte, Thomas J. Bannan, Thomas G. Bell, David Berry, Lucy J. Carpenter, Hugh Coe, Andrew Coward, Peter Edwards, Daniel Feltham, Dwayne Heard, Jim Hopkins, James Keeble, Elizabeth C. Kent, Brian A. King, Isobel R. Lawrence, James Lee, Claire R. Macintosh, Alex Megann, Bengamin I. Moat, Katie Read, Chris Reed, Malcolm J. Roberts, Reinhard Schiemann, David Schroeder, Timothy J. Smyth, Loren Temple, Navaneeth Thamban, Lisa Whalley, Simon Williams, Huihui Wu, and Mingxi Yang
Earth Syst. Sci. Data, 17, 135–164, https://doi.org/10.5194/essd-17-135-2025, https://doi.org/10.5194/essd-17-135-2025, 2025
Short summary
Short summary
Here, we present an overview of the data generated as part of the North Atlantic Climate System Integrated Study (ACSIS) programme that are available through dedicated repositories at the Centre for Environmental Data Analysis (CEDA; www.ceda.ac.uk) and the British Oceanographic Data Centre (BODC; bodc.ac.uk). The datasets described here cover the North Atlantic Ocean, the atmosphere above (it including its composition), and Arctic sea ice.
Maria R. Russo, Sadie L. Bartholomew, David Hassell, Alex M. Mason, Erica Neininger, A. James Perman, David A. J. Sproson, Duncan Watson-Parris, and Nathan Luke Abraham
Geosci. Model Dev., 18, 181–191, https://doi.org/10.5194/gmd-18-181-2025, https://doi.org/10.5194/gmd-18-181-2025, 2025
Short summary
Short summary
Observational data and modelling capabilities have expanded in recent years, but there are still barriers preventing these two data sources from being used in synergy. Proper comparison requires generating, storing, and handling a large amount of data. This work describes the first step in the development of a new set of software tools, the VISION toolkit, which can enable the easy and efficient integration of observational and model data required for model evaluation.
Ryan Hossaini, David Sherry, Zihao Wang, Martyn P. Chipperfield, Wuhu Feng, David E. Oram, Karina E. Adcock, Stephen A. Montzka, Isobel J. Simpson, Andrea Mazzeo, Amber A. Leeson, Elliot Atlas, and Charles C.-K. Chou
Atmos. Chem. Phys., 24, 13457–13475, https://doi.org/10.5194/acp-24-13457-2024, https://doi.org/10.5194/acp-24-13457-2024, 2024
Short summary
Short summary
DCE (1,2-dichloroethane) is an industrial chemical used to produce PVC (polyvinyl chloride). We analysed DCE production data to estimate global DCE emissions (2002–2020). The emissions were included in an atmospheric model and evaluated by comparing simulated DCE to DCE measurements in the troposphere. We show that DCE contributes ozone-depleting Cl to the stratosphere and that this has increased with increasing DCE emissions. DCE’s impact on stratospheric O3 is currently small but non-zero.
Matthew Henry, Ewa M. Bednarz, and Jim Haywood
Atmos. Chem. Phys., 24, 13253–13268, https://doi.org/10.5194/acp-24-13253-2024, https://doi.org/10.5194/acp-24-13253-2024, 2024
Short summary
Short summary
Stratospheric aerosol injection (SAI) refers to a climate intervention by which aerosols are intentionally added to the high atmosphere to increase the amount of reflected sunlight and reduce Earth's temperature. The climate outcomes of SAI depend on the latitude of injection. While injecting aerosols at the Equator has undesirable side effects, injecting away from the Equator has different effects on temperature, rainfall, ozone, and atmospheric circulation, which are analysed in this work.
Chris Wilson, Brian J. Kerridge, Richard Siddans, David P. Moore, Lucy J. Ventress, Emily Dowd, Wuhu Feng, Martyn P. Chipperfield, and John J. Remedios
Atmos. Chem. Phys., 24, 10639–10653, https://doi.org/10.5194/acp-24-10639-2024, https://doi.org/10.5194/acp-24-10639-2024, 2024
Short summary
Short summary
The leaks from the Nord Stream gas pipelines in September 2022 released a large amount of methane (CH4) into the atmosphere. We provide observational data from a satellite instrument that shows a large CH4 plume over the North Sea off the coast of Scandinavia. We use this together with atmospheric models to quantify the CH4 leaked into the atmosphere from the pipelines. We find that 219–427 Gg CH4 was emitted, making this the largest individual fossil-fuel-related CH4 leak on record.
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.
Yang Li, Wuhu Feng, Xin Zhou, Yajuan Li, and Martyn P. Chipperfield
Atmos. Chem. Phys., 24, 8277–8293, https://doi.org/10.5194/acp-24-8277-2024, https://doi.org/10.5194/acp-24-8277-2024, 2024
Short summary
Short summary
The Tibetan Plateau (TP), the highest and largest plateau, experiences strong surface solar UV radiation, whose excess can cause harmful influences on local biota. Hence, it is critical to study TP ozone. We find ENSO, the strongest interannual phenomenon, tends to induce tropospheric temperature change and thus modulate tropopause variability, which in turn favours ozone change over the TP. Our results have implications for a better understanding of the interannual variability of TP ozone.
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.
Emily Dowd, Alistair J. Manning, Bryn Orth-Lashley, Marianne Girard, James France, Rebecca E. Fisher, Dave Lowry, Mathias Lanoisellé, Joseph R. Pitt, Kieran M. Stanley, Simon O'Doherty, Dickon Young, Glen Thistlethwaite, Martyn P. Chipperfield, Emanuel Gloor, and Chris Wilson
Atmos. Meas. Tech., 17, 1599–1615, https://doi.org/10.5194/amt-17-1599-2024, https://doi.org/10.5194/amt-17-1599-2024, 2024
Short summary
Short summary
We provide the first validation of the satellite-derived emission estimates using surface-based mobile greenhouse gas surveys of an active gas leak detected near Cheltenham, UK. GHGSat’s emission estimates broadly agree with the surface-based mobile survey and steps were taken to fix the leak, highlighting the importance of satellite data in identifying emissions and helping to reduce our human impact on climate change.
Yan Zhang, Douglas G. MacMartin, Daniele Visioni, Ewa M. Bednarz, and Ben Kravitz
Earth Syst. Dynam., 15, 191–213, https://doi.org/10.5194/esd-15-191-2024, https://doi.org/10.5194/esd-15-191-2024, 2024
Short summary
Short summary
Injecting SO2 into the lower stratosphere can temporarily reduce global mean temperature and mitigate some risks associated with climate change, but injecting it at different latitudes and seasons would have different impacts. This study introduces new stratospheric aerosol injection (SAI) strategies and explores the importance of the choice of SAI strategy, demonstrating that it notably affects the distribution of aerosol cloud, injection efficiency, and various surface climate impacts.
Lily Gouldsbrough, Ryan Hossaini, Emma Eastoe, Paul J. Young, and Massimo Vieno
Atmos. Chem. Phys., 24, 3163–3196, https://doi.org/10.5194/acp-24-3163-2024, https://doi.org/10.5194/acp-24-3163-2024, 2024
Short summary
Short summary
High-resolution spatial fields of surface ozone are used to understand spikes in ozone concentration and predict their impact on public health. Such fields are routinely output from complex mathematical models for atmospheric conditions. These outputs are on a coarse spatial resolution and the highest concentrations tend to be biased. Using a novel data-driven machine learning methodology, we show how such output can be corrected to produce fields with both lower bias and higher resolution.
Martyn P. Chipperfield and Slimane Bekki
Atmos. Chem. Phys., 24, 2783–2802, https://doi.org/10.5194/acp-24-2783-2024, https://doi.org/10.5194/acp-24-2783-2024, 2024
Short summary
Short summary
We give a personal perspective on recent issues related to the depletion of stratospheric ozone and some newly emerging challenges. We first provide a brief review of historic work on understanding the ozone layer and review ozone recovery from the effects of halogenated source gases and the Montreal Protocol. We then discuss the recent observations of ozone depletion from Australian fires in early 2020 and the Hunga Tonga–Hunga Ha'apai volcano in January 2022.
Ailish M. Graham, Richard J. Pope, Martyn P. Chipperfield, Sandip S. Dhomse, Matilda Pimlott, Wuhu Feng, Vikas Singh, Ying Chen, Oliver Wild, Ranjeet Sokhi, and Gufran Beig
Atmos. Chem. Phys., 24, 789–806, https://doi.org/10.5194/acp-24-789-2024, https://doi.org/10.5194/acp-24-789-2024, 2024
Short summary
Short summary
Our paper uses novel satellite datasets and high-resolution emissions datasets alongside a back-trajectory model to investigate the balance of local and external sources influencing NOx air pollution changes in Delhi. We find in the post-monsoon season that NOx from local and non-local transport emissions contributes most to poor air quality in Delhi. Therefore, air quality mitigation strategies in Delhi and surrounding regions are used to control this issue.
Andrea Pazmiño, Florence Goutail, Sophie Godin-Beekmann, Alain Hauchecorne, Jean-Pierre Pommereau, Martyn P. Chipperfield, Wuhu Feng, Franck Lefèvre, Audrey Lecouffe, Michel Van Roozendael, Nis Jepsen, Georg Hansen, Rigel Kivi, Kimberly Strong, and Kaley A. Walker
Atmos. Chem. Phys., 23, 15655–15670, https://doi.org/10.5194/acp-23-15655-2023, https://doi.org/10.5194/acp-23-15655-2023, 2023
Short summary
Short summary
The vortex-averaged ozone loss over the last 3 decades is evaluated for both polar regions using the passive ozone tracer of the chemical transport model TOMCAT/SLIMCAT and total ozone observations from the SAOZ network and MSR2 reanalysis. Three metrics were developed to compute ozone trends since 2000. The study confirms the ozone recovery in the Antarctic and shows a potential sign of quantitative detection of ozone recovery in the Arctic that needs to be robustly confirmed in the future.
Richard J. Pope, Brian J. Kerridge, Richard Siddans, Barry G. Latter, Martyn P. Chipperfield, Wuhu Feng, Matilda A. Pimlott, Sandip S. Dhomse, Christian Retscher, and Richard Rigby
Atmos. Chem. Phys., 23, 14933–14947, https://doi.org/10.5194/acp-23-14933-2023, https://doi.org/10.5194/acp-23-14933-2023, 2023
Short summary
Short summary
Ozone is a potent air pollutant, and we present the first study to investigate long-term changes in lower tropospheric column ozone (LTCO3) from space. We have constructed a merged LTCO3 dataset from GOME-1, SCIAMACHY and OMI between 1996 and 2017. Comparing LTCO3 between the 1996–2000 and 2013–2017 5-year averages, we find significant positive increases in the tropics/sub-tropics, while in the northern mid-latitudes, we find small-scale differences.
Ben A. Cala, Scott Archer-Nicholls, James Weber, N. Luke Abraham, Paul T. Griffiths, Lorrie Jacob, Y. Matthew Shin, Laura E. Revell, Matthew Woodhouse, and Alexander T. Archibald
Atmos. Chem. Phys., 23, 14735–14760, https://doi.org/10.5194/acp-23-14735-2023, https://doi.org/10.5194/acp-23-14735-2023, 2023
Short summary
Short summary
Dimethyl sulfide (DMS) is an important trace gas emitted from the ocean recognised as setting the sulfate aerosol background, but its oxidation is complex. As a result representation in chemistry-climate models is greatly simplified. We develop and compare a new mechanism to existing mechanisms via a series of global and box model experiments. Our studies show our updated DMS scheme is a significant improvement but significant variance exists between mechanisms.
Sandip S. Dhomse and Martyn P. Chipperfield
Earth Syst. Sci. Data, 15, 5105–5120, https://doi.org/10.5194/essd-15-5105-2023, https://doi.org/10.5194/essd-15-5105-2023, 2023
Short summary
Short summary
There are no long-term stratospheric profile data sets for two very important greenhouse gases: methane (CH4) and nitrous oxide (N2O). Along with radiative feedback, these species play an important role in controlling ozone loss in the stratosphere. Here, we use machine learning to fuse satellite measurements with a chemical model to construct long-term gap-free profile data sets for CH4 and N2O. We aim to construct similar data sets for other important trace gases (e.g. O3, Cly, NOy species).
Ewa M. Bednarz, Amy H. Butler, Daniele Visioni, Yan Zhang, Ben Kravitz, and Douglas G. MacMartin
Atmos. Chem. Phys., 23, 13665–13684, https://doi.org/10.5194/acp-23-13665-2023, https://doi.org/10.5194/acp-23-13665-2023, 2023
Short summary
Short summary
We use a state-of-the-art Earth system model and a set of stratospheric aerosol injection (SAI) strategies to achieve the same level of global mean surface cooling through different combinations of location and/or timing of the injection. We demonstrate that the choice of SAI strategy can lead to contrasting impacts on stratospheric and tropospheric temperatures, circulation, and chemistry (including stratospheric ozone), thereby leading to different impacts on regional surface climate.
Ewa M. Bednarz, Ryan Hossaini, and Martyn P. Chipperfield
Atmos. Chem. Phys., 23, 13701–13711, https://doi.org/10.5194/acp-23-13701-2023, https://doi.org/10.5194/acp-23-13701-2023, 2023
Short summary
Short summary
We quantify, for the first time, the time-varying impact of uncontrolled emissions of chlorinated very short-lived substances (Cl-VSLSs) on stratospheric ozone using a state-of-the-art chemistry-climate model. We demonstrate that Cl-VSLSs already have a non-negligible impact on stratospheric ozone, including a local reduction of up to ~7 DU in Arctic ozone in the cold winter of 2019/20, and any so future growth in emissions will continue to offset some of the benefits of the Montreal Protocol.
Ewa M. Bednarz, Ryan Hossaini, N. Luke Abraham, and Martyn P. Chipperfield
Geosci. Model Dev., 16, 6187–6209, https://doi.org/10.5194/gmd-16-6187-2023, https://doi.org/10.5194/gmd-16-6187-2023, 2023
Short summary
Short summary
Development and performance of the new DEST chemistry scheme of UM–UKCA is described. The scheme extends the standard StratTrop scheme by including important updates to the halogen chemistry, thus allowing process-oriented studies of stratospheric ozone depletion and recovery, including impacts from both controlled long-lived ozone-depleting substances and emerging issues around uncontrolled, very short-lived substances. It will thus aid studies in support of future ozone assessment reports.
Matthew Henry, Jim Haywood, Andy Jones, Mohit Dalvi, Alice Wells, Daniele Visioni, Ewa M. Bednarz, Douglas G. MacMartin, Walker Lee, and Mari R. Tye
Atmos. Chem. Phys., 23, 13369–13385, https://doi.org/10.5194/acp-23-13369-2023, https://doi.org/10.5194/acp-23-13369-2023, 2023
Short summary
Short summary
Solar climate interventions, such as injecting sulfur in the stratosphere, may be used to offset some of the adverse impacts of global warming. We use two independently developed Earth system models to assess the uncertainties around stratospheric sulfur injections. The injection locations and amounts are optimized to maintain the same pattern of surface temperature. While both models show reduced warming, the change in rainfall patterns (even without sulfur injections) is uncertain.
Richard J. Pope, Brian J. Kerridge, Martyn P. Chipperfield, Richard Siddans, Barry G. Latter, Lucy J. Ventress, Matilda A. Pimlott, Wuhu Feng, Edward Comyn-Platt, Garry D. Hayman, Stephen R. Arnold, and Ailish M. Graham
Atmos. Chem. Phys., 23, 13235–13253, https://doi.org/10.5194/acp-23-13235-2023, https://doi.org/10.5194/acp-23-13235-2023, 2023
Short summary
Short summary
In the summer of 2018, Europe experienced several persistent large-scale ozone (O3) pollution episodes. Satellite tropospheric O3 and surface O3 data recorded substantial enhancements in 2018 relative to other years. Targeted model simulations showed that meteorological processes and emissions controlled the elevated surface O3, while mid-tropospheric O3 enhancements were dominated by stratospheric O3 intrusion and advection of North Atlantic O3-rich air masses into Europe.
Monali Borthakur, Miriam Sinnhuber, Alexandra Laeng, Thomas Reddmann, Peter Braesicke, Gabriele Stiller, Thomas von Clarmann, Bernd Funke, Ilya Usoskin, Jan Maik Wissing, and Olesya Yakovchuk
Atmos. Chem. Phys., 23, 12985–13013, https://doi.org/10.5194/acp-23-12985-2023, https://doi.org/10.5194/acp-23-12985-2023, 2023
Short summary
Short summary
Reduced ozone levels resulting from ozone depletion mean more exposure to UV radiation, which has various effects on human health. We analysed solar events to see what influence it has on the chemistry of Earth's atmosphere and how this atmospheric chemistry change can affect the ozone. To do this, we used an atmospheric model considering only chemistry and compared it with satellite data. The focus was mainly on the contribution of chlorine, and we found about 10 %–20 % ozone loss due to that.
Yajuan Li, Sandip S. Dhomse, Martyn P. Chipperfield, Wuhu Feng, Jianchun Bian, Yuan Xia, and Dong Guo
Atmos. Chem. Phys., 23, 13029–13047, https://doi.org/10.5194/acp-23-13029-2023, https://doi.org/10.5194/acp-23-13029-2023, 2023
Short summary
Short summary
For the first time a regularized multivariate regression model is used to estimate stratospheric ozone trends. Regularized regression avoids the over-fitting issue due to correlation among explanatory variables. We demonstrate that there are considerable differences in satellite-based and chemical-model-based ozone trends, highlighting large uncertainties in our understanding about ozone variability. We argue that caution is needed when interpreting results with different methods and datasets.
Michael P. Cartwright, Richard J. Pope, Jeremy J. Harrison, Martyn P. Chipperfield, Chris Wilson, Wuhu Feng, David P. Moore, and Parvadha Suntharalingam
Atmos. Chem. Phys., 23, 10035–10056, https://doi.org/10.5194/acp-23-10035-2023, https://doi.org/10.5194/acp-23-10035-2023, 2023
Short summary
Short summary
A 3-D chemical transport model, TOMCAT, is used to simulate global atmospheric carbonyl sulfide (OCS) distribution. Modelled OCS compares well with satellite observations of OCS from limb-sounding satellite observations. Model simulations also compare adequately with surface and atmospheric observations and suitably capture the seasonality of OCS and background concentrations.
Luana S. Basso, Chris Wilson, Martyn P. Chipperfield, Graciela Tejada, Henrique L. G. Cassol, Egídio Arai, Mathew Williams, T. Luke Smallman, Wouter Peters, Stijn Naus, John B. Miller, and Manuel Gloor
Atmos. Chem. Phys., 23, 9685–9723, https://doi.org/10.5194/acp-23-9685-2023, https://doi.org/10.5194/acp-23-9685-2023, 2023
Short summary
Short summary
The Amazon’s carbon balance may have changed due to forest degradation, deforestation and warmer climate. We used an atmospheric model and atmospheric CO2 observations to quantify Amazonian carbon emissions (2010–2018). The region was a small carbon source to the atmosphere, mostly due to fire emissions. Forest uptake compensated for ~ 50 % of the fire emissions, meaning that the remaining forest is still a small carbon sink. We found no clear evidence of weakening carbon uptake over the period.
Emily Dowd, Chris Wilson, Martyn P. Chipperfield, Emanuel Gloor, Alistair Manning, and Ruth Doherty
Atmos. Chem. Phys., 23, 7363–7382, https://doi.org/10.5194/acp-23-7363-2023, https://doi.org/10.5194/acp-23-7363-2023, 2023
Short summary
Short summary
Surface observations of methane show that the seasonal cycle amplitude (SCA) of methane is decreasing in the northern high latitudes (NHLs) but increased globally (1995–2020). The NHL decrease is counterintuitive, as we expect the SCA to increase with increasing concentrations. We use a chemical transport model to investigate changes in SCA in the NHLs. We find well-mixed methane and changes in emissions from Canada, the Middle East, and Europe are the largest contributors to the SCA in NHLs.
Christian Scharun, Roland Ruhnke, and Peter Braesicke
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2023-91, https://doi.org/10.5194/gmd-2023-91, 2023
Publication in GMD not foreseen
Short summary
Short summary
The identification and quantification of greenhouse gas (GHG) emissions is an important task for monitoring mitigation strategies under climate change. With RICHARD 1.0, we developed a novel approach using spatiotemporal proxy data and a selection algorithm to detect GHG emission hotspots. By using a one year dataset of global climate model output we showed that RICHARD is able to determine and quantify the source strengths of GHG emission hotspots much more precisely than conventional methods.
Maria Rosa Russo, Brian John Kerridge, Nathan Luke Abraham, James Keeble, Barry Graham Latter, Richard Siddans, James Weber, Paul Thomas Griffiths, John Adrian Pyle, and Alexander Thomas Archibald
Atmos. Chem. Phys., 23, 6169–6196, https://doi.org/10.5194/acp-23-6169-2023, https://doi.org/10.5194/acp-23-6169-2023, 2023
Short summary
Short summary
Tropospheric ozone is an important component of the Earth system as it can affect both climate and air quality. In this work we use observed tropospheric ozone derived from satellite observations and compare it to tropospheric ozone from model simulations. Our aim is to investigate recent changes (2005–2018) in tropospheric ozone in the North Atlantic region and to understand what factors are driving such changes.
Peter Joyce, Cristina Ruiz Villena, Yahui Huang, Alex Webb, Manuel Gloor, Fabien H. Wagner, Martyn P. Chipperfield, Rocío Barrio Guilló, Chris Wilson, and Hartmut Boesch
Atmos. Meas. Tech., 16, 2627–2640, https://doi.org/10.5194/amt-16-2627-2023, https://doi.org/10.5194/amt-16-2627-2023, 2023
Short summary
Short summary
Methane emissions are responsible for a lot of the warming caused by the greenhouse effect, much of which comes from a small number of point sources. We can identify methane point sources by analysing satellite data, but it requires a lot of time invested by experts and is prone to very high errors. Here, we produce a neural network that can automatically identify methane point sources and estimate the mass of methane that is being released per hour and are able to do so with far smaller errors.
Scott Archer-Nicholls, Rachel Allen, Nathan L. Abraham, Paul T. Griffiths, and Alex T. Archibald
Atmos. Chem. Phys., 23, 5801–5813, https://doi.org/10.5194/acp-23-5801-2023, https://doi.org/10.5194/acp-23-5801-2023, 2023
Short summary
Short summary
The nitrate radical is a major oxidant at nighttime, but much less is known about it than about the other oxidants ozone and OH. We use Earth system model calculations to show how the nitrate radical has changed in abundance from 1850–2014 and to 2100 under a range of different climate and emission scenarios. Depending on the emissions and climate scenario, significant increases are projected with implications for the oxidation of volatile organic compounds and the formation of fine aerosol.
Antonio G. Bruno, Jeremy J. Harrison, Martyn P. Chipperfield, David P. Moore, Richard J. Pope, Christopher Wilson, Emmanuel Mahieu, and Justus Notholt
Atmos. Chem. Phys., 23, 4849–4861, https://doi.org/10.5194/acp-23-4849-2023, https://doi.org/10.5194/acp-23-4849-2023, 2023
Short summary
Short summary
A 3-D chemical transport model, TOMCAT; satellite data; and ground-based observations have been used to investigate hydrogen cyanide (HCN) variability. We found that the oxidation by O(1D) drives the HCN loss in the middle stratosphere and the currently JPL-recommended OH reaction rate overestimates HCN atmospheric loss. We also evaluated two different ocean uptake schemes. We found them to be unrealistic, and we need to scale these schemes to obtain good agreement with HCN observations.
Eric Förster, Harald Bönisch, Marco Neumaier, Florian Obersteiner, Andreas Zahn, Andreas Hilboll, Anna B. Kalisz Hedegaard, Nikos Daskalakis, Alexandros Panagiotis Poulidis, Mihalis Vrekoussis, Michael Lichtenstern, and Peter Braesicke
Atmos. Chem. Phys., 23, 1893–1918, https://doi.org/10.5194/acp-23-1893-2023, https://doi.org/10.5194/acp-23-1893-2023, 2023
Short summary
Short summary
The airborne megacity campaign EMeRGe provided an unprecedented amount of trace gas measurements. We combine measured volatile organic compounds (VOCs) with trajectory-modelled emission uptakes to identify potential source regions of pollution. We also characterise the chemical fingerprints (e.g. biomass burning and anthropogenic signatures) of the probed air masses to corroborate the contributing source regions. Our approach is the first large-scale study of VOCs originating from megacities.
Ewa M. Bednarz, Daniele Visioni, Ben Kravitz, Andy Jones, James M. Haywood, Jadwiga Richter, Douglas G. MacMartin, and Peter Braesicke
Atmos. Chem. Phys., 23, 687–709, https://doi.org/10.5194/acp-23-687-2023, https://doi.org/10.5194/acp-23-687-2023, 2023
Short summary
Short summary
Building on Part 1 of this two-part study, we demonstrate the role of biases in climatological circulation and specific aspects of model microphysics in driving the differences in simulated sulfate distributions amongst three Earth system models. We then characterize the simulated changes in stratospheric and free-tropospheric temperatures, ozone, water vapor, and large-scale circulation, elucidating the role of the above aspects in the surface responses discussed in Part 1.
Daniele Visioni, Ewa M. Bednarz, Walker R. Lee, Ben Kravitz, Andy Jones, Jim M. Haywood, and Douglas G. MacMartin
Atmos. Chem. Phys., 23, 663–685, https://doi.org/10.5194/acp-23-663-2023, https://doi.org/10.5194/acp-23-663-2023, 2023
Short summary
Short summary
The paper constitutes Part 1 of a study performing a first systematic inter-model comparison of the atmospheric responses to stratospheric sulfate aerosol injections (SAIs) at various latitudes as simulated by three state-of-the-art Earth system models. We identify similarities and differences in the modeled aerosol burden, investigate the differences in the aerosol approaches between the models, and ultimately show the differences produced in surface climate, temperature and precipitation.
Robert J. Parker, Chris Wilson, Edward Comyn-Platt, Garry Hayman, Toby R. Marthews, A. Anthony Bloom, Mark F. Lunt, Nicola Gedney, Simon J. Dadson, Joe McNorton, Neil Humpage, Hartmut Boesch, Martyn P. Chipperfield, Paul I. Palmer, and Dai Yamazaki
Biogeosciences, 19, 5779–5805, https://doi.org/10.5194/bg-19-5779-2022, https://doi.org/10.5194/bg-19-5779-2022, 2022
Short summary
Short summary
Wetlands are the largest natural source of methane, one of the most important climate gases. The JULES land surface model simulates these emissions. We use satellite data to evaluate how well JULES reproduces the methane seasonal cycle over different tropical wetlands. It performs well for most regions; however, it struggles for some African wetlands influenced heavily by river flooding. We explain the reasons for these deficiencies and highlight how future development will improve these areas.
Markus Jesswein, Rafael P. Fernandez, Lucas Berná, Alfonso Saiz-Lopez, Jens-Uwe Grooß, Ryan Hossaini, Eric C. Apel, Rebecca S. Hornbrook, Elliot L. Atlas, Donald R. Blake, Stephen Montzka, Timo Keber, Tanja Schuck, Thomas Wagenhäuser, and Andreas Engel
Atmos. Chem. Phys., 22, 15049–15070, https://doi.org/10.5194/acp-22-15049-2022, https://doi.org/10.5194/acp-22-15049-2022, 2022
Short summary
Short summary
This study presents the global and seasonal distribution of the two major brominated short-lived substances CH2Br2 and CHBr3 in the upper troposphere and lower stratosphere based on observations from several aircraft campaigns. They show similar seasonality for both hemispheres, except in the respective hemispheric autumn lower stratosphere. A comparison with the TOMCAT and CAM-Chem models shows good agreement in the annual mean but larger differences in the seasonal consideration.
Yajuan Li, Sandip S. Dhomse, Martyn P. Chipperfield, Wuhu Feng, Andreas Chrysanthou, Yuan Xia, and Dong Guo
Atmos. Chem. Phys., 22, 10635–10656, https://doi.org/10.5194/acp-22-10635-2022, https://doi.org/10.5194/acp-22-10635-2022, 2022
Short summary
Short summary
Chemical transport models forced with (re)analysis meteorological fields are ideally suited for interpreting the influence of important physical processes on the ozone variability. We use TOMCAT forced by ECMWF ERA-Interim and ERA5 reanalysis data sets to investigate the effects of reanalysis forcing fields on ozone changes. Our results show that models forced by ERA5 reanalyses may not yet be capable of reproducing observed changes in stratospheric ozone, particularly in the lower stratosphere.
Matilda A. Pimlott, Richard J. Pope, Brian J. Kerridge, Barry G. Latter, Diane S. Knappett, Dwayne E. Heard, Lucy J. Ventress, Richard Siddans, Wuhu Feng, and Martyn P. Chipperfield
Atmos. Chem. Phys., 22, 10467–10488, https://doi.org/10.5194/acp-22-10467-2022, https://doi.org/10.5194/acp-22-10467-2022, 2022
Short summary
Short summary
We present a new method to derive global information of the hydroxyl radical (OH), an important atmospheric oxidant. OH controls the lifetime of trace gases important to air quality and climate. We use satellite observations of ozone, carbon monoxide, methane and water vapour in a simple expression to derive OH around 3–4 km altitude. The derived OH compares well to model and aircraft OH data. We then apply the method to 10 years of satellite data to study the inter-annual variability of OH.
Simone Tilmes, Daniele Visioni, Andy Jones, James Haywood, Roland Séférian, Pierre Nabat, Olivier Boucher, Ewa Monica Bednarz, and Ulrike Niemeier
Atmos. Chem. Phys., 22, 4557–4579, https://doi.org/10.5194/acp-22-4557-2022, https://doi.org/10.5194/acp-22-4557-2022, 2022
Short summary
Short summary
This study assesses the impacts of climate interventions, using stratospheric sulfate aerosol and solar dimming on stratospheric ozone, based on three Earth system models with interactive stratospheric chemistry. The climate interventions have been applied to a high emission (baseline) scenario in order to reach global surface temperatures of a medium emission scenario. We find significant increases and decreases in total column ozone, depending on regions and seasons.
Beatriz M. Monge-Sanz, Alessio Bozzo, Nicholas Byrne, Martyn P. Chipperfield, Michail Diamantakis, Johannes Flemming, Lesley J. Gray, Robin J. Hogan, Luke Jones, Linus Magnusson, Inna Polichtchouk, Theodore G. Shepherd, Nils Wedi, and Antje Weisheimer
Atmos. Chem. Phys., 22, 4277–4302, https://doi.org/10.5194/acp-22-4277-2022, https://doi.org/10.5194/acp-22-4277-2022, 2022
Short summary
Short summary
The stratosphere is emerging as one of the keys to improve tropospheric weather and climate predictions. This study provides evidence of the role the stratospheric ozone layer plays in improving weather predictions at different timescales. Using a new ozone modelling approach suitable for high-resolution global models that provide operational forecasts from days to seasons, we find significant improvements in stratospheric meteorological fields and stratosphere–troposphere coupling.
Richard J. Pope, Rebecca Kelly, Eloise A. Marais, Ailish M. Graham, Chris Wilson, Jeremy J. Harrison, Savio J. A. Moniz, Mohamed Ghalaieny, Steve R. Arnold, and Martyn P. Chipperfield
Atmos. Chem. Phys., 22, 4323–4338, https://doi.org/10.5194/acp-22-4323-2022, https://doi.org/10.5194/acp-22-4323-2022, 2022
Short summary
Short summary
Nitrogen oxides (NOx) are potent air pollutants which directly impact on human health. In this study, we use satellite nitrogen dioxide (NO2) data to evaluate the spatial distribution and temporal evolution of the UK official NOx emissions inventory, with reasonable agreement. We also derived satellite-based NOx emissions for several UK cities. In the case of London and Birmingham, the NAEI NOx emissions are potentially too low by >50%.
Piera Raspollini, Enrico Arnone, Flavio Barbara, Massimo Bianchini, Bruno Carli, Simone Ceccherini, Martyn P. Chipperfield, Angelika Dehn, Stefano Della Fera, Bianca Maria Dinelli, Anu Dudhia, Jean-Marie Flaud, Marco Gai, Michael Kiefer, Manuel López-Puertas, David P. Moore, Alessandro Piro, John J. Remedios, Marco Ridolfi, Harjinder Sembhi, Luca Sgheri, and Nicola Zoppetti
Atmos. Meas. Tech., 15, 1871–1901, https://doi.org/10.5194/amt-15-1871-2022, https://doi.org/10.5194/amt-15-1871-2022, 2022
Short summary
Short summary
The MIPAS instrument onboard the ENVISAT satellite provided 10 years of measurements of the atmospheric emission al limb that allow for the retrieval of latitude- and altitude-resolved atmospheric composition. We describe the improvements implemented in the retrieval algorithm used for the full mission reanalysis, which allows for the generation of the global distributions of 21 atmospheric constituents plus temperature with increased accuracy with respect to previously generated data.
Florian Haenel, Wolfgang Woiwode, Jennifer Buchmüller, Felix Friedl-Vallon, Michael Höpfner, Sören Johansson, Farahnaz Khosrawi, Oliver Kirner, Anne Kleinert, Hermann Oelhaf, Johannes Orphal, Roland Ruhnke, Björn-Martin Sinnhuber, Jörn Ungermann, Michael Weimer, and Peter Braesicke
Atmos. Chem. Phys., 22, 2843–2870, https://doi.org/10.5194/acp-22-2843-2022, https://doi.org/10.5194/acp-22-2843-2022, 2022
Short summary
Short summary
We compare remote sensing observations of H2O, O3, HNO3 and clouds in the upper troposphere–lowermost stratosphere during an Arctic winter long-range research flight with simulations by two different state-of-the-art model systems. We find good agreement for dynamical structures, trace gas distributions and clouds. We investigate model biases and sensitivities, with the goal of aiding model development and improving our understanding of processes in the upper troposphere–lowermost stratosphere.
Sandip S. Dhomse, Martyn P. Chipperfield, Wuhu Feng, Ryan Hossaini, Graham W. Mann, Michelle L. Santee, and Mark Weber
Atmos. Chem. Phys., 22, 903–916, https://doi.org/10.5194/acp-22-903-2022, https://doi.org/10.5194/acp-22-903-2022, 2022
Short summary
Short summary
Solar flux variations associated with 11-year sunspot cycle is believed to exert important external climate forcing. As largest variations occur at shorter wavelengths such as ultra-violet part of the solar spectrum, associated changes in stratospheric ozone are thought to provide direct evidence for solar climate interaction. Until now, most of the studies reported double-peak structured solar cycle signal (SCS), but relatively new satellite data suggest only single-peak-structured SCS.
Sandip S. Dhomse, Carlo Arosio, Wuhu Feng, Alexei Rozanov, Mark Weber, and Martyn P. Chipperfield
Earth Syst. Sci. Data, 13, 5711–5729, https://doi.org/10.5194/essd-13-5711-2021, https://doi.org/10.5194/essd-13-5711-2021, 2021
Short summary
Short summary
High-quality long-term ozone profile data sets are key to estimating short- and long-term ozone variability. Almost all the satellite (and chemical model) data sets show some kind of bias with respect to each other. This is because of differences in measurement methodologies as well as simplified processes in the models. We use satellite data sets and chemical model output to generate 42 years of ozone profile data sets using a random-forest machine-learning algorithm that is named ML-TOMCAT.
Paul D. Hamer, Virginie Marécal, Ryan Hossaini, Michel Pirre, Gisèle Krysztofiak, Franziska Ziska, Andreas Engel, Stephan Sala, Timo Keber, Harald Bönisch, Elliot Atlas, Kirstin Krüger, Martyn Chipperfield, Valery Catoire, Azizan A. Samah, Marcel Dorf, Phang Siew Moi, Hans Schlager, and Klaus Pfeilsticker
Atmos. Chem. Phys., 21, 16955–16984, https://doi.org/10.5194/acp-21-16955-2021, https://doi.org/10.5194/acp-21-16955-2021, 2021
Short summary
Short summary
Bromoform is a stratospheric ozone-depleting gas released by seaweed and plankton transported to the stratosphere via convection in the tropics. We study the chemical interactions of bromoform and its derivatives within convective clouds using a cloud-scale model and observations. Our findings are that soluble bromine gases are efficiently washed out and removed within the convective clouds and that most bromine is transported vertically to the upper troposphere in the form of bromoform.
Christopher J. Diekmann, Matthias Schneider, Benjamin Ertl, Frank Hase, Omaira García, Farahnaz Khosrawi, Eliezer Sepúlveda, Peter Knippertz, and Peter Braesicke
Earth Syst. Sci. Data, 13, 5273–5292, https://doi.org/10.5194/essd-13-5273-2021, https://doi.org/10.5194/essd-13-5273-2021, 2021
Short summary
Short summary
The joint analysis of different stable water isotopes in water vapour is a powerful tool for investigating atmospheric moisture pathways. This paper presents a novel global and multi-annual dataset of H2O and HDO in mid-tropospheric water vapour by using data from the satellite sensor Metop/IASI. Due to its unique combination of coverage and resolution in space and time, this dataset is highly promising for studying the hydrological cycle and its representation in weather and climate models.
Anthony C. Jones, Adrian Hill, Samuel Remy, N. Luke Abraham, Mohit Dalvi, Catherine Hardacre, Alan J. Hewitt, Ben Johnson, Jane P. Mulcahy, and Steven T. Turnock
Atmos. Chem. Phys., 21, 15901–15927, https://doi.org/10.5194/acp-21-15901-2021, https://doi.org/10.5194/acp-21-15901-2021, 2021
Short summary
Short summary
Ammonium nitrate is hard to model because it forms and evaporates rapidly. One approach is to relate its equilibrium concentration to temperature, humidity, and the amount of nitric acid and ammonia gases. Using this approach, we limit the rate at which equilibrium is reached using various condensation rates in a climate model. We show that ammonium nitrate concentrations are highly sensitive to the condensation rate. Our results will help improve the representation of nitrate in climate models.
Meike K. Rotermund, Vera Bense, Martyn P. Chipperfield, Andreas Engel, Jens-Uwe Grooß, Peter Hoor, Tilman Hüneke, Timo Keber, Flora Kluge, Benjamin Schreiner, Tanja Schuck, Bärbel Vogel, Andreas Zahn, and Klaus Pfeilsticker
Atmos. Chem. Phys., 21, 15375–15407, https://doi.org/10.5194/acp-21-15375-2021, https://doi.org/10.5194/acp-21-15375-2021, 2021
Short summary
Short summary
Airborne total bromine (Brtot) and tracer measurements suggest Brtot-rich air masses persistently protruded into the lower stratosphere (LS), creating a high Brtot region over the North Atlantic in fall 2017. The main source is via isentropic transport by the Asian monsoon and to a lesser extent transport across the extratropical tropopause as quantified by a Lagrange model. The transport of Brtot via Central American hurricanes is also observed. Lastly, the impact of Brtot on LS O3 is assessed.
Cited articles
Archibald, A. T., O'Connor, F. M., Abraham, N. L., Archer-Nicholls, S., Chipperfield, M. P., Dalvi, M., Folberth, G. A., Dennison, F., Dhomse, S. S., Griffiths, P. T., Hardacre, C., Hewitt, A. J., Hill, R. S., Johnson, C. E., Keeble, J., Köhler, M. O., Morgenstern, O., Mulcahy, J. P., Ordóñez, C., Pope, R. J., Rumbold, S. T., Russo, M. R., Savage, N. H., Sellar, A., Stringer, M., Turnock, S. T., Wild, O., and Zeng, G.: Description and evaluation of the UKCA stratosphere–troposphere chemistry scheme (StratTrop vn 1.0) implemented in UKESM1, Geosci. Model Dev., 13, 1223–1266, https://doi.org/10.5194/gmd-13-1223-2020, 2020.
Bais, A. F., Lucas, R. M., Bornman, J. F., Williamson, C. E., Sulzberger, B., Austin, A. T., Wilson, S. R., Andrady, A. L., Bernhard, G., McKenzie, R. L., Aucamp, P. J., Madronich, S., Neale, R. E., Yazar, S., Young, A. R., de Gruijl, F. R., Norval, M., Takizawa, Y., Barnes, P. W., Robson, T. M., Robinson, S. A., Ballaré, C. L., Flint, S. D., Neale, P. J., Hylander, S., Rose, K. C., Wängberg, S.-Å., Häder, D.-P., Worrest, R. C., Zepp, R. G., Paul, N. D., Cory, R. M., Solomon, K. R., Longstreth, J., Pandey, K. K., Redhwi, H. H., Torikai, A., and Heikkilä, A. M.: Environmental effects of ozone
depletion, UV radiation and interactions with climate change: UNEP
Environmental Effects Assessment Panel, update 2017, Photochem. Photobio.
S., 17, 127–179, https://doi.org/10.1039/c7pp90043k, 2018.
Bednarz, E. M.: Data used in: Atmospheric impacts of chlorinated very short-lived substances over the recent past – Part 1: Stratospheric chlorine budget and the role of transport, by: Bednarz et al. (2022) (1.0) Zenodo [data set], https://doi.org/10.5281/zenodo.6993693, 2022.
Bednarz, E. M., Hossaini, R., Abraham, N. L., and Chipperfield, M. C.: Description
and evaluation of the new UM-UKCA Double Extended Stratospheric-Tropospheric
(DEST vn1.0) scheme for comprehensive modelling of halogen chemistry in the
stratosphere, in preparation, 2022.
Bernath, P. and Fernando, A. M.: Trends in stratospheric HCl from the ACE
satellite mission, J. Quant. Spectrosc. Ra., 217, 126–129, https://doi.org/10.1016/j.jqsrt.2018.05.027, 2018.
Boone, C. D., Walker, K. A., and Bernath, P. F.: Version 3 retrievals for the
Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS),
in: The Atmospheric Chemistry Experiment ACE at 10: A
solar occultation anthology, edited by: Bernath, P. F., 103–127, Hampton, VA, A. Deepak
Publishing, ISBN: 978-0-937194-54-9, 2013 (data available at: http://www.ace.uwaterloo.ca/data.php, last access: 18 July 2022).
Chipperfield, M. P., Hossaini, R., Montzka, S. A., Reimann, S., Sherry, D., and Tegtmeier, S.:
Renewed and emerging concerns over the production and emission of
ozone-depleting substances, Nat. Rev. Earth Environ., 1,
251–263, 2020.
Chrysanthou, A., Maycock, A. C., Chipperfield, M. P., Dhomse, S., Garny, H., Kinnison, D., Akiyoshi, H., Deushi, M., Garcia, R. R., Jöckel, P., Kirner, O., Pitari, G., Plummer, D. A., Revell, L., Rozanov, E., Stenke, A., Tanaka, T. Y., Visioni, D., and Yamashita, Y.: The effect of atmospheric nudging on the stratospheric residual circulation in chemistry–climate models, Atmos. Chem. Phys., 19, 11559–11586, https://doi.org/10.5194/acp-19-11559-2019, 2019.
Claxton, T., Hossaini, R., Wilson, C., Montzka, S. A., Chipperfield, M. P.,
Wild, O., Bednarz, E. M., Carpenter, L. J., Andrews, S. J., Hackenberg, S. C., Mühle, J., Oram, D., Park, S., Park, M.-K., Atlas, E., Navarro, M., Schauffler, S., Sherry, D., Vollmer, M., Schuck, T., Engel, A., Krummel, P. B., Maione, M., Arduini, J., Saito, T., Yokouchi, Y., O'Doherty, S., Young, D., and Lunder, C.: A synthesis inversion to constrain global emissions of two
very short lived chlorocarbons: dichloromethane, and perchloroethylene,
J. Geophys. Res.-Atmos., 125, e2019JD031818,
https://doi.org/10.1029/2019JD031818, 2020.
Dee, D. P., Uppala, S. M., Simmons, A. J., Berrisford, P., Poli, P.,
Kobayashi, S., Andrae, U., Balmaseda, M. A., Balsamo, G., Bauer, P.,
Bechtold, P., Beljaars, A. C. M., van de Berg, I., Biblot, J., Bormann, N.,
Delsol, C., Dragani, R., Fuentes, M., Greer, A. J., Haimberger, L., Healy,
S. B., Hersbach, H., Holm, E. V., Isaksen, L., Kallberg, P., Kohler, M.,
Matricardi, M., McNally, A. P., Mong-Sanz, B. M., Morcette, J.-J., Park,
B.-K., Peubey, C., de Rosnay, P., Tavolato, C., Thepaut, J. N., and Vitart,
F.: The ERA-Interim reanalysis: Configuration and performance of the data
assimilation system, Q. J. Roy. Meteor. Soc., 137, 553–597,
https://doi.org/10.1002/qj.828, 2011 (data available at: https://www.ecmwf.int/en/forecasts/datasets/reanalysis-datasets/era-interim, last access: 18 July 2022).
Dhomse, S. S., Kinnison, D., Chipperfield, M. P., Salawitch, R. J., Cionni, I., Hegglin, M. I., Abraham, N. L., Akiyoshi, H., Archibald, A. T., Bednarz, E. M., Bekki, S., Braesicke, P., Butchart, N., Dameris, M., Deushi, M., Frith, S., Hardiman, S. C., Hassler, B., Horowitz, L. W., Hu, R.-M., Jöckel, P., Josse, B., Kirner, O., Kremser, S., Langematz, U., Lewis, J., Marchand, M., Lin, M., Mancini, E., Marécal, V., Michou, M., Morgenstern, O., O'Connor, F. M., Oman, L., Pitari, G., Plummer, D. A., Pyle, J. A., Revell, L. E., Rozanov, E., Schofield, R., Stenke, A., Stone, K., Sudo, K., Tilmes, S., Visioni, D., Yamashita, Y., and Zeng, G.: Estimates of ozone return dates from Chemistry-Climate Model Initiative simulations, Atmos. Chem. Phys., 18, 8409–8438, https://doi.org/10.5194/acp-18-8409-2018, 2018.
Diallo, M., Ern, M., and Ploeger, F.: The advective Brewer–Dobson circulation in the ERA5 reanalysis: climatology, variability, and trends, Atmos. Chem. Phys., 21, 7515–7544, https://doi.org/10.5194/acp-21-7515-2021, 2021.
Durack, P. J. and Taylor, K. E.: PCMDI AMIP SST and sea-ice boundary
conditions version 1.1.0. Version 20160906, Earth System Grid Federation,
https://doi.org/10.22033/ESGF/input4MIPs.1120, 2016.
Engel, A., Rigby, M., Burkholder, J. B., Fernandez, R. P., Froidevaux, L.,
Hall, B. D., Hossaini, R., Saito, T., Vollmer, M. K., and Yao, B.: Update on ozone-depleting substances (ODSs) and other
gases of interest to the Montreal Protocol, in: Scientific assessment of
ozone depletion: 2018, Global Ozone Research and Monitorting
Project–Report No. 58, Chap. 1, Geneva, Switzerland: World Meterological
Organization, 2018.
Fang, X., Park, S., Saito, T., Tunnicliffe, R., Ganesan, A. L., Rigby, M.,
Li, S., Yokouchi, Y., Fraser, P. J., Harth, C. M., Krummel, P. B.,
Mühle, J., O'Doherty, S., Salameh, P. K., Simmonds, P. G., Weiss, R. F.,
Young, D., Lunt, M. F., Manning, A. J., Gressent, A., and Prinn, R. G.:
Rapid increase in ozone-depleting chloroform emissions from China, Nat.
Geosci., 12, 89–93, 2019.
Feng, Y., Bie, P., Wang, Z., Wang, L., and Zhang, J.: Bottom-up
anthropogenic dichloromethane emission estimates from China for the period
2005–2016 and predictions of future emissions, Atmos. Environ.,
186, 241–247, https://doi.org/10.1016/j.atmosenv.2018.05.039, 2018.
Fernandez, R. P., Barrera, J. A., López-Noreña, A. I., Kinnison, D.
E., Nicely, J., Salawitch, R. J., Wales, P. A., Toselli, B. M., Tilmes, S., Lamarque, J.-F., Cuevas, C. A., and Saiz-Lopez, A.: Intercomparison between surrogate,
explicit and full treatments of VSL bromine chemistry within the CAM-Chem
chemistry-climate model, Geophys. Res. Lett., 48, e2020GL091125, https://doi.org/10.1029/2020GL091125,
2021.
Froidevaux, L., Anderson, J., Wang, H.-J., Fuller, R. A., Schwartz, M. J., Santee, M. L., Livesey, N. J., Pumphrey, H. C., Bernath, P. F., Russell III, J. M., and McCormick, M. P.: Global OZone Chemistry And Related trace gas Data records for the Stratosphere (GOZCARDS): methodology and sample results with a focus on HCl, H2O, and O3, Atmos. Chem. Phys., 15, 10471–10507, https://doi.org/10.5194/acp-15-10471-2015, 2015.
Fu, D., Boone, C. D., Bernath, P. F., Walker, K. A., Nassar, R., Manney, G. L., and McLeod, S. D.: Global phosgene observations from the Atmospheric Chemistry Experiment (ACE) mission, Geophys. Res. Lett., 34, L17815, https://doi.org/10.1029/2007GL029942, 2007.
Harrison, J. J., Chipperfield, M. P., Hossaini, R., Boone, C. D., Dhomse,
S., Feng, W., and Bernath, P. F.: Phosgene in the upper troposphere and
lower stratosphere: A marker for product gas injection due to
chlorine-containing very short-lived substances, Geophys. Res.
Lett., 46, 1032–1039, https://doi.org/10.1029/2018GL079784, 2019.
Hersbach, H., Bell, B., Berrisford, P., Hirahara, S., Horányi, A., Muñoz-Sabater, J., Nicolas, J., Peubey, C., Radu, R., Schepers, D., Simmons, A., Soci, C., Abdalla, S., Abellan, X., Balsamo, G., Bechtold, P., Biavati, G., Bidlot, J., Bonavita, M., De Chiara, G., Dahlgren, P., Dee, D., Diamantakis, M., Dragani, R., Flemming, J., Forbes, R., Fuentes, M., Geer, A., Haimberger, L., Healy, S., Hogan, R. J., Hólm, E., Janisková, M., Keeley, S., Laloyaux, P., Lopez, P., Lupu, C., Radnoti, G., de Rosnay, P., Rozum, I., Vamborg, F., Villaume, S., and Thépaut, J.-N.: The ERA5 global reanalysis, Q. J.
Roy. Meteor. Soc., 146, 1999–2049, https://doi.org/10.1002/qj.3803, 2020 (data available at: https://www.ecmwf.int/en/forecasts/datasets/reanalysis-datasets/era5, last access: 12 August 2022).
Hossaini, R., Chipperfield, M. P., Montzka, S. A., Rap, A., Dhomse, S., and
Feng, W.: Efficiency of short-lived halogens at influencing climate through
depletion of stratospheric ozone, Nat. Geosci., 8, 186–190,
https://doi.org/10.1038/ngeo2363, 2015.
Hossaini, R., Patra, P. K., Leeson, A. A., Krysztofiak, G., Abraham, N. L., Andrews, S. J., Archibald, A. T., Aschmann, J., Atlas, E. L., Belikov, D. A., Bönisch, H., Carpenter, L. J., Dhomse, S., Dorf, M., Engel, A., Feng, W., Fuhlbrügge, S., Griffiths, P. T., Harris, N. R. P., Hommel, R., Keber, T., Krüger, K., Lennartz, S. T., Maksyutov, S., Mantle, H., Mills, G. P., Miller, B., Montzka, S. A., Moore, F., Navarro, M. A., Oram, D. E., Pfeilsticker, K., Pyle, J. A., Quack, B., Robinson, A. D., Saikawa, E., Saiz-Lopez, A., Sala, S., Sinnhuber, B.-M., Taguchi, S., Tegtmeier, S., Lidster, R. T., Wilson, C., and Ziska, F.: A multi-model intercomparison of halogenated very short-lived substances (TransCom-VSLS): linking oceanic emissions and tropospheric transport for a reconciled estimate of the stratospheric source gas injection of bromine, Atmos. Chem. Phys., 16, 9163–9187, https://doi.org/10.5194/acp-16-9163-2016, 2016a.
Hossaini, R., Chipperfield, M. P., Saiz-Lopez, A., Fernandez, R., Monks, S.,
Feng, W., Brauer, P., and von Glasow, R.: A global model of tropospheric
chlorine chemistry: Organic versus inorganic sources and impact on methane
oxidation, J. Geophys. Res.-Atmos., 121, 14271–14297, https://doi.org/10.1002/2016JD025756, 2016b.
Hossaini, R., Atlas, E., Dhomse, S. S., Chipperfield, M. P., Bernath, P. F., Fernando, A. M., Mühle, J., Leeson, A. A., Montzka, S. A., Feng, W., Harrison, J. J., Krummel, P., Vollmer, M. K., Reimann, S., O'Doherty, S., Young, D., Maione, M., Arduini, J., and Lunder, C. R.: Recent trends in stratospheric chlorine from very
short-lived substances, J. Geophys. Res.-Atmos., 124,
2318–2335, https://doi.org/10.1029/2018JD029400, 2019.
Keber, T., Bönisch, H., Hartick, C., Hauck, M., Lefrancois, F., Obersteiner, F., Ringsdorf, A., Schohl, N., Schuck, T., Hossaini, R., Graf, P., Jöckel, P., and Engel, A.: Bromine from short-lived source gases in the extratropical northern hemispheric upper troposphere and lower stratosphere (UTLS), Atmos. Chem. Phys., 20, 4105–4132, https://doi.org/10.5194/acp-20-4105-2020, 2020.
Laube, J. C., Engel, A., Bönisch, H., Möbius, T., Worton, D. R., Sturges, W. T., Grunow, K., and Schmidt, U.: Contribution of very short-lived organic substances to stratospheric chlorine and bromine in the tropics – a case study, Atmos. Chem. Phys., 8, 7325–7334, https://doi.org/10.5194/acp-8-7325-2008, 2008.
Leedham Elvidge, E. C., Oram, D. E., Laube, J. C., Baker, A. K., Montzka, S. A., Humphrey, S., O'Sullivan, D. A., and Brenninkmeijer, C. A. M.: Increasing concentrations of dichloromethane, CH2Cl2, inferred from CARIBIC air samples collected 1998–2012, Atmos. Chem. Phys., 15, 1939–1958, https://doi.org/10.5194/acp-15-1939-2015, 2015.
Mahieu, E., Chipperfield, M. P., Notholt, J., Reddmann, T., Anderson, J., Bernath, P. F., Blumenstock, T., Coffey, M. T., Dhomse, S. S., Feng, W., Franco, B., Froidevaux, L., Griffith, D. W. T., Hannigan, J. W., Hase, F., Hossaini, R., Jones, N. B., Morino, I., Murata, I., Nakajima, H., Palm, M., Paton-Walsh, C., Russell III, J. M., Schneider, M., Servais, C., Smale, D., Walker, K. A.: Recent Northern Hemisphere
stratospheric HCl increase due to atmospheric circulation changes, Nature,
515, 104–107, https://doi.org/10.1038/nature13857, 2014.
Meinshausen, M., Vogel, E., Nauels, A., Lorbacher, K., Meinshausen, N., Etheridge, D. M., Fraser, P. J., Montzka, S. A., Rayner, P. J., Trudinger, C. M., Krummel, P. B., Beyerle, U., Canadell, J. G., Daniel, J. S., Enting, I. G., Law, R. M., Lunder, C. R., O'Doherty, S., Prinn, R. G., Reimann, S., Rubino, M., Velders, G. J. M., Vollmer, M. K., Wang, R. H. J., and Weiss, R.: Historical greenhouse gas concentrations for climate modelling (CMIP6), Geosci. Model Dev., 10, 2057–2116, https://doi.org/10.5194/gmd-10-2057-2017, 2017.
Meinshausen, M., Nicholls, Z. R. J., Lewis, J., Gidden, M. J., Vogel, E., Freund, M., Beyerle, U., Gessner, C., Nauels, A., Bauer, N., Canadell, J. G., Daniel, J. S., John, A., Krummel, P. B., Luderer, G., Meinshausen, N., Montzka, S. A., Rayner, P. J., Reimann, S., Smith, S. J., van den Berg, M., Velders, G. J. M., Vollmer, M. K., and Wang, R. H. J.: The shared socio-economic pathway (SSP) greenhouse gas concentrations and their extensions to 2500, Geosci. Model Dev., 13, 3571–3605, https://doi.org/10.5194/gmd-13-3571-2020, 2020.
Morgenstern, O., Braesicke, P., O'Connor, F. M., Bushell, A. C., Johnson, C. E., Osprey, S. M., and Pyle, J. A.: Evaluation of the new UKCA climate-composition model – Part 1: The stratosphere, Geosci. Model Dev., 2, 43–57, https://doi.org/10.5194/gmd-2-43-2009, 2009.
Neu, J., Flury, T., Manney, G., Santee, M. L., Livesey, N. J., and Worden, J.: Tropospheric ozone variations governed
by changes in stratospheric circulation, Nat. Geosci., 7, 340–344, 2014.
Nowack, P., Luke Abraham, N., Maycock, A. C., Braesicke, P., Gregory, J. M., Joshi, M. M., Osprey, A., and Pyle, J. A.: A large ozone-circulation
feedback and its implications for global warming assessments, Nat. Clim.
Change, 5, 41–45, https://doi.org/10.1038/nclimate2451, 2015.
Oman, L. D., Douglass, A. R., Salawitch, R. J., Canty, T. P., Ziemke, J. R.,
and Manyin, M.: The effect of representing bromine from VSLS on the
simulation and evolution of Antarctic ozone, Geophys. Res. Lett., 43,
9869–9876, https://doi.org/10.1002/2016gl070471, 2016.
Oram, D. E., Ashfold, M. J., Laube, J. C., Gooch, L. J., Humphrey, S., Sturges, W. T., Leedham-Elvidge, E., Forster, G. L., Harris, N. R. P., Mead, M. I., Samah, A. A., Phang, S. M., Ou-Yang, C.-F., Lin, N.-H., Wang, J.-L., Baker, A. K., Brenninkmeijer, C. A. M., and Sherry, D.: A growing threat to the ozone layer from short-lived anthropogenic chlorocarbons, Atmos. Chem. Phys., 17, 11929–11941, https://doi.org/10.5194/acp-17-11929-2017, 2017.
Orbe, C., Yang, H., Waugh, D. W., Zeng, G., Morgenstern , O., Kinnison, D. E., Lamarque, J.-F., Tilmes, S., Plummer, D. A., Scinocca, J. F., Josse, B., Marecal, V., Jöckel, P., Oman, L. D., Strahan, S. E., Deushi, M., Tanaka, T. Y., Yoshida, K., Akiyoshi, H., Yamashita, Y., Stenke, A., Revell, L., Sukhodolov, T., Rozanov, E., Pitari, G., Visioni, D., Stone, K. A., Schofield, R., and Banerjee, A.: Large-scale tropospheric transport in the Chemistry–Climate Model Initiative (CCMI) simulations, Atmos. Chem. Phys., 18, 7217–7235, https://doi.org/10.5194/acp-18-7217-2018, 2018.
Ordóñez, C., Lamarque, J.-F., Tilmes, S., Kinnison, D. E., Atlas, E. L., Blake, D. R., Sousa Santos, G., Brasseur, G., and Saiz-Lopez, A.: Bromine and iodine chemistry in a global chemistry-climate model: description and evaluation of very short-lived oceanic sources, Atmos. Chem. Phys., 12, 1423–1447, https://doi.org/10.5194/acp-12-1423-2012, 2012.
Ploeger, F., Riese, M., Haenel, F., Konopka, P., Müller, R., and Stiller, G.:
Variability of stratospheric mean age of air and of the local effects of
residual circulation and eddy mixing, J. Geophys. Res.-Atmos., 120,
716–733, https://doi.org/10.1002/2014JD022468, 2015.
Ploeger, F., Diallo, M., Charlesworth, E., Konopka, P., Legras, B., Laube, J. C., Grooß, J.-U., Günther, G., Engel, A., and Riese, M.: The stratospheric Brewer–Dobson circulation inferred from age of air in the ERA5 reanalysis, Atmos. Chem. Phys., 21, 8393–8412, https://doi.org/10.5194/acp-21-8393-2021, 2021.
Quack, B. and Wallace, D. W. R.: Air-sea flux of bromoform: Controls,
rates, and implications, Global Biogeochem. Cy., 17, 1023,
https://doi.org/10.1029/2002GB001890, 2003.
Reynolds, R. W. and Smith, T. M.: Improved global sea surface temperature
analyses using optimum interpolation, J. Climate, 7, 929–948, 1994.
Sellar, A. A., Jones, C. G., Mulcahy, J. P., Tang, Y., Yool, A., Wiltshire,
A., O'Connor, F. M., Stringer, M., Hill, R., Palmieri, J., Woodward, S., de
Mora, L., Kuhlbrodt, T., Rumbold, S. T., Kelley, D. I., Ellis, R., Johnson,
C. E., Walton, J., Abraham, N. L., Andrews, M. B., Andrews, T., Archibald,
A. T., Berthou, S., Burke, E., Blockley, E., Carslaw, K., Dalvi, M.,
Edwards, J., Folberth, G. A., Gedney, N., Griffiths, P. T., Harper, A. B.,
Hendry, M. A., Hewitt, A. J., Johnson, B., Jones, A., Jones, C. D., Keeble,
J., Liddicoat, S., Morgenstern, O., Parker, R. J., Predoi, V., Robertson,
E., Siahaan, A., Smith, R. S., Swaminathan, R., Woodhouse, M. T., Zeng, G.,
and Zerroukat, M.: UKESM1: Description and evaluation of the U.K. Earth
System Model, J. Adv. Model. Earth Sy., 11, 4513–4558,
https://doi.org/10.1029/2019MS001739, 2019.
Sellar, A., Walton, J., Jones, C. G., Abraham, N. L., Andrejczuk, M.,
Andrews, M. B., Andrews, T., Archibald, A. T., de Mora, L., Dyson, H.,
Elkington, M., Ellis, R., Florek, P., Good, P., Gohar, L., Haddad, S.,
Hardiman, S. C., Hogan, E., Iwi, A., Jones, C. D., Johnson, B., Kelley, D.
I., Kettleborough, J., Knight, J. R., Köhler, M. O., Kuhlbrodt, T.,
Liddicoat, S., Linova-Pavlova, I., Mizielinski, M. S., Morgenstern, O.,
Mulcahy, J., Neininger, E., O'Connor, F. M., Petrie, R., Ridley, J., Rioual,
J.-C., Roberts, M., Robertson, E., Rumbold, S., Seddon, J., Shepherd, H.,
Shim, S., Stephens, A., Teixeira, J. C., Tang, Y., Williams, J., and Wiltshire,
A.: Implementation of UK Earth system models for CMIP, J. Adv. Model.
Earth Sy., 12, e2019MS001946, https://doi.org/10.1029/2019MS001946, 2020.
Son, S. W., Tandon, N. F., Polvani, L. M., and Waugh, D. W.: Ozone hole and
Southern Hemisphere climate change, Geophys. Res. Lett., 36, L15705,
https://doi.org/10.1029/2009gl038671, 2009.
Stiller, G. P., Harrison, J. J., Haenel, F. J., Glatthor, N., Kellmann, S., and von Clarmann, T.: Improved global distributions of SF6 and mean age of stratospheric air by use of new spectroscopic data, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2660, https://doi.org/10.5194/egusphere-egu2020-2660, 2020.
Sturges, W., Oram, D., Carpenter, L., Penkett, S., and Engel, A.: Bromoform
as a source of stratospheric bromine, Geophys. Res. Lett., 27, 2081–2084,
https://doi.org/10.1029/2000GL011444, 2000.
Telford, P. J., Braesicke, P., Morgenstern, O., and Pyle, J. A.: Technical Note: Description and assessment of a nudged version of the new dynamics Unified Model, Atmos. Chem. Phys., 8, 1701–1712, https://doi.org/10.5194/acp-8-1701-2008, 2008.
Thomason, L. W., Ernest, N., Millán, L., Rieger, L., Bourassa, A., Vernier, J.-P., Manney, G., Luo, B., Arfeuille, F., and Peter, T.: A global space-based stratospheric aerosol climatology: 1979–2016, Earth Syst. Sci. Data, 10, 469–492, https://doi.org/10.5194/essd-10-469-2018, 2018.
Wales, P. A., Salawitch, R. J., Nicely, J. M., Anderson, D. C., Canty, T. P., Baidar, S., Dix, B., Koenig, T. K., Volkamer, R., Chen, D., Huey, L. G., Tanner, D. J., Cuevas, C. A., Fernandez, R. P., Kinnison, D. E., Lamarque, J.-F., Saiz-Lopez, A., Atlas, E. L., Hall, S. R., Navarro, M. A., Pan, L. L., Schauffler, S. M., Stell, M., Tilmes, S., Ullmann, K., Weinheimer, A. J., Akiyoshi, H., Chipperfield, M. P., Deushi, M., Dhomse, S. S., Feng, W., Graf, P., Hossaini, R., Jöckel, P., Mancini, E., Michou, M., Morgenstern, O., Oman, L. D., Pitari, G., Plummer, D. A., Revell, L. E., Rozanov, E., Saint-Martin, D., Schofield, R., Stenke, A., Stone, K. A., Visioni, D., Yamashita, Y., and Zeng, G.: Stratospheric injection of brominated very
short-lived substances: Aircraft observations in the Western Pacific and
representation in global models, J. Geophys. Res.-Atmos., 123, 5690–5719,
https://doi.org/10.1029/2017JD027978, 2018.
Walters, D., Baran, A. J., Boutle, I., Brooks, M., Earnshaw, P., Edwards, J., Furtado, K., Hill, P., Lock, A., Manners, J., Morcrette, C., Mulcahy, J., Sanchez, C., Smith, C., Stratton, R., Tennant, W., Tomassini, L., Van Weverberg, K., Vosper, S., Willett, M., Browse, J., Bushell, A., Carslaw, K., Dalvi, M., Essery, R., Gedney, N., Hardiman, S., Johnson, B., Johnson, C., Jones, A., Jones, C., Mann, G., Milton, S., Rumbold, H., Sellar, A., Ujiie, M., Whitall, M., Williams, K., and Zerroukat, M.: The Met Office Unified Model Global Atmosphere 7.0/7.1 and JULES Global Land 7.0 configurations, Geosci. Model Dev., 12, 1909–1963, https://doi.org/10.5194/gmd-12-1909-2019, 2019.
Wargan, K., Orbe, C., Pawson, S., Ziemke, J. R., Oman, L. D., Olsen, M. A., Coy, L., and Knowland, K. E.: Recent decline in extratropical lower stratospheric ozone attributed
to circulation changes, Geophys. Res. Lett., 45, 5166–5176,
https://doi.org/10.1029/2018GL077406, 2018.
Wofsy, S. C.: HIAPER Pole-to-Pole Observations (HIPPO): fine-grained,
global-scale measurements of climatically important atmospheric gases and
aerosols, Philos. T. Roy. Soc. A, 369, 2073–2086,
https://doi.org/10.1098/rsta.2010.0313, 2011.
WMO (World Meteorological Organization): Scientific Assessment of Ozone
Depletion: 2018, Global Ozone Research and Monitoring Project-Report No. 58,
World Meteorological Organization, Geneva, Switzerland, 2018.
Short summary
Atmospheric impacts of chlorinated very short-lived substances (Cl-VSLS) over the first two decades of the 21st century are assessed using the UM-UKCA chemistry–climate model. Stratospheric input of Cl from Cl-VSLS is estimated at ~130 ppt in 2019. The use of model set-up with constrained meteorology significantly increases the abundance of Cl-VSLS in the lower stratosphere relative to the free-running set-up. The growth in Cl-VSLS emissions significantly impacted recent HCl and COCl2 trends.
Atmospheric impacts of chlorinated very short-lived substances (Cl-VSLS) over the first two...
Altmetrics
Final-revised paper
Preprint