Articles | Volume 20, issue 21
https://doi.org/10.5194/acp-20-12483-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-20-12483-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
31 Oct 2020
Research article |
| 31 Oct 2020
| 31 Oct 2020
Polar stratospheric clouds initiated by mountain waves in a global chemistry–climate model: a missing piece in fully modelling polar stratospheric ozone depletion
Andrew Orr
CORRESPONDING AUTHOR
British Antarctic Survey, Cambridge, UK
J. Scott Hosking
British Antarctic Survey, Cambridge, UK
Aymeric Delon
Ecole normale supérieure Paris-Saclay, Paris, France
Lars Hoffmann
Forschungszentrum Jülich, Jülich Supercomputing Centre,
Jülich, Germany
Reinhold Spang
Forschungszentrum Jülich, Institut für Energie und
Klimaforschung, Stratosphäre, IEK-7, Jülich, Germany
Tracy Moffat-Griffin
British Antarctic Survey, Cambridge, UK
James Keeble
National Centre for Atmospheric Science (NCAS), University of
Cambridge, Cambridge, UK
Department of Chemistry, University of Cambridge, Cambridge, UK
Nathan Luke Abraham
National Centre for Atmospheric Science (NCAS), University of
Cambridge, Cambridge, UK
Department of Chemistry, University of Cambridge, Cambridge, UK
Peter Braesicke
Karlsruher Institut für Technologie, Institut für Meteorologie und Klimaforschung, Karlsruhe, Germany
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Robin S. Smith, Tarkan A. Bilge, Thomas J. Bracegirdle, Paul R. Holland, Till Kuhlbrodt, Charlotte Lang, Spencer Liddicoat, Tom Mitcham, Jane Mulcahy, Kaitlin A. Naughten, Andrew Orr, Julien Palmieri, Antony J. Payne, Steven Rumbold, Marc Stringer, Ranjini Swaminathan, Sarah Taylor, Jeremy Walton, and Colin Jones
Earth Syst. Dynam., 17, 475–493, https://doi.org/10.5194/esd-17-475-2026, https://doi.org/10.5194/esd-17-475-2026, 2026
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This study investigates how tropical ozone levels have changed since 2000 in chemistry climate models and satellite observations to determine how well they agree with one another, and to see if current trends can help predict future levels. At some, satellite records disagree significantly on the magnitude of ozone changes. The study shows a connection between recent ozone trends and future ozone levels, suggesting that satellite measurements could help constrain future ozone changes.
Isabelle Sangha, Nathan Luke Abraham, Andrew Orr, Hua Lu, Michael C. Pitts, Lamont R. Poole, and Michael Weimer
EGUsphere, https://doi.org/10.5194/egusphere-2026-128, https://doi.org/10.5194/egusphere-2026-128, 2026
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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 observed wave ice still fails to form in the model, 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 cloud formation in mountain waves.
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
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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.
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
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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
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Hamish D. Pritchard, Edward C. King, David J. Goodger, Douglas Boyle, Daniel N. Goldberg, Beatriz Recinos, Andrew Orr, and Dhananjay Regmi
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We present a new and uniquely extensive dataset of glacier thickness from the Khumbu Himal around Mount Everest that stretches for 119 km, doubling the extent of thickness measurements in High Mountain Asia. Such measurements are key inputs for models that estimate how much ice is stored on the whole mountain range scale and for models that predict how this ice reserve will change in future, and what impact this will have on water supply for the large populations living downstream.
Jingyu Wang, Gabriel Chiodo, Blanca Ayarzagüena, William T. Ball, Mohamadou Diallo, Birgit Hassler, James Keeble, Peer Nowack, Clara Orbe, Sandro Vattioni, and Timofei Sukhodolov
Atmos. Chem. Phys., 25, 17819–17844, https://doi.org/10.5194/acp-25-17819-2025, https://doi.org/10.5194/acp-25-17819-2025, 2025
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We analyzed the ozone response under elevated CO2 using the data from CMIP6 DECK experiments. We then examined the relations between ozone response and changes in temperature and circulation to identify the drivers of ozone change. The climate feedback of ozone is investigated through offline calculations and by comparing models with and without interactive chemistry. We find that ozone–climate interactions are important for Earth system models and thus should be considered in future model development.
Peter G. Berthelemy, Corwin J. Wright, Neil P. Hindley, Phoebe E. Noble, and Lars Hoffmann
Atmos. Chem. Phys., 25, 17595–17611, https://doi.org/10.5194/acp-25-17595-2025, https://doi.org/10.5194/acp-25-17595-2025, 2025
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Atmospheric gravity waves are one of the key mechanisms for moving energy upwards through the atmosphere. We use temperature data to see them from a satellite, and here have made a new method to automatically detect them. This works by seeing if points next to each other are from the same wave. This is useful for creating larger gravity wave datasets without noise, which can then be used by climate forecasters to improve their understanding of the atmosphere.
Arno Keppens, Daan Hubert, José Granville, Oindrila Nath, Jean-Christopher Lambert, Catherine Wespes, Pierre-François Coheur, Cathy Clerbaux, Anne Boynard, Richard Siddans, Barry Latter, Brian Kerridge, Serena Di Pede, Pepijn Veefkind, Juan Cuesta, Gaelle Dufour, Klaus-Peter Heue, Melanie Coldewey-Egbers, Diego Loyola, Andrea Orfanoz-Cheuquelaf, Swathi Maratt Satheesan, Kai-Uwe Eichmann, Alexei Rozanov, Viktoria F. Sofieva, Jerald R. Ziemke, Antje Inness, Roeland Van Malderen, and Lars Hoffmann
Atmos. Meas. Tech., 18, 6893–6916, https://doi.org/10.5194/amt-18-6893-2025, https://doi.org/10.5194/amt-18-6893-2025, 2025
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The first Tropospheric Ozone Assessment Report (TOAR) encountered discrepancies between several satellite sensors’ estimates of the distribution and change of ozone in the free troposphere. Therefore, contributing to the second TOAR, we harmonise as much as possible the observational perspective of sixteen tropospheric ozone products from satellites. This only partially accounts for the observed discrepancies, with a reduction of 10–40 % of the inter-product dispersion upon harmonisation.
Martina Krämer, Nicole Spelten, Christian Rolf, and Reinhold Spang
Atmos. Chem. Phys., 25, 13563–13583, https://doi.org/10.5194/acp-25-13563-2025, https://doi.org/10.5194/acp-25-13563-2025, 2025
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The size and number of cirrus ice crystals is one parameter influencing the still uncertain effect of cirrus clouds on climate. Here, the occurrence of ice particle sizes and concentrations with varying temperature and cloud microphysical thickness is analyzed as well as whether they formed in-situ or were transported upwards as frozen droplets from further below. The analyses are based on a large database of airborne measurements and extensive simulations.
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
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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.
Ales Kuchar, Gunter Stober, Dimitry Pokhotelov, Huixin Liu, Han-Li Liu, Manfred Ern, Damian Murphy, Diego Janches, Tracy Moffat-Griffin, Nicholas Mitchell, and Christoph Jacobi
EGUsphere, https://doi.org/10.5194/egusphere-2025-2827, https://doi.org/10.5194/egusphere-2025-2827, 2025
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We studied how the healing of the Antarctic ozone layer is affecting winds high above the South Pole. Using ground-based radar, satellite data, and computer models, we found that winds in the upper atmosphere have become stronger over the past two decades. These changes appear to be linked to shifts in the lower atmosphere caused by ozone recovery. Our results show that human efforts to repair the ozone layer are also influencing climate patterns far above Earth’s surface.
Gabriel Augusto Giongo, Cristiano Max Wrasse, Pierre-Dominique Pautet, José Valentin Bageston, Prosper Kwamla Nyassor, Cosme Alexandre Oliveira Barros Figueiredo, Anderson Vestena Bilibio, Tracy Moffat-Griffin, Damian John Murphy, Toyese Tunde Ayorinde, Delano Gobbi, and Hisao Takahashi
EGUsphere, https://doi.org/10.5194/egusphere-2025-3114, https://doi.org/10.5194/egusphere-2025-3114, 2025
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This work analyzes the medium-scale atmospheric gravity waves observed by ground-based airglow imaging over the Antarctic continent. Medium-scale gravity waves refer to waves larger than 50 km of horizontal wavelength, and have not been analyzed in that region so far. Wave parameters and horizontal propagation characteristics were obtained by a recently improved methodology and are described thoroughly.
Marc Girona-Mata, Andrew Orr, Martin Widmann, Daniel Bannister, Ghulam Hussain Dars, Scott Hosking, Jesse Norris, David Ocio, Tony Phillips, Jakob Steiner, and Richard E. Turner
Hydrol. Earth Syst. Sci., 29, 3073–3100, https://doi.org/10.5194/hess-29-3073-2025, https://doi.org/10.5194/hess-29-3073-2025, 2025
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We introduce a novel method for improving daily precipitation maps in mountain regions and pilot it across three basins in the Hindu Kush Himalaya (HKH). The approach leverages climate model and weather station data, along with statistical or machine learning techniques. Our results show that this approach outperforms traditional methods, especially in remote ungauged areas, suggesting that it could be used to improve precipitation maps across much of the HKH, as well as other mountain regions.
Farahnaz Khosrawi and Lars Hoffmann
EGUsphere, https://doi.org/10.5194/egusphere-2025-3147, https://doi.org/10.5194/egusphere-2025-3147, 2025
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Computer performance has increased immensely in recent years, but the ability to store data has only increased slightly. This presents scientists with major challenges. Many compression methods have been developed in recent years with which data can be stored either lossless or lossy. Here we test three of these methods: two lossy compression methods and one lossless compressor. Our study shows that compression is a valuable tool to cope with the high demand of disk space from these data sets.
Arthur Gauthier, Claudia Borries, Alexander Kozlovsky, Diego Janches, Peter Brown, Denis Vida, Christoph Jacobi, Damian Murphy, Masaki Tsutsumi, Njål Gulbrandsen, Satonori Nozawa, Mark Lester, Johan Kero, Nicholas Mitchell, Tracy Moffat-Griffin, and Gunter Stober
Ann. Geophys., 43, 427–440, https://doi.org/10.5194/angeo-43-427-2025, https://doi.org/10.5194/angeo-43-427-2025, 2025
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This study focuses on a TIMED Doppler Interferometer (TIDI)–meteor radar (MR) comparison of zonal and meridional winds and their dependence on local time and latitude. The correlation calculation between TIDI wind measurements and MR winds shows good agreement. A TIDI–MR seasonal comparison and analysis of the altitude–latitude dependence for winds are performed. TIDI reproduces the mean circulation well when compared with MRs and may be a useful lower boundary for general circulation models.
Mingzhao Liu, Lars Hoffmann, Jens-Uwe Grooß, Zhongyin Cai, Sabine Grießbach, and Yi Heng
Atmos. Chem. Phys., 25, 4403–4418, https://doi.org/10.5194/acp-25-4403-2025, https://doi.org/10.5194/acp-25-4403-2025, 2025
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We studied the transport and chemical decomposition of volcanic SO2, focusing on the 2019 Raikoke event. By comparing two different chemistry modeling schemes, we found that including complex chemical reactions leads to a more accurate prediction of how long SO2 stays in the atmosphere. This research helps improve our understanding of volcanic pollution and its impact on air quality and climate, providing better tools for scientists to track and predict the movement of these pollutants.
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
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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.
Ella Gilbert, Denis Pishniak, José Abraham Torres, Andrew Orr, Michelle Maclennan, Nander Wever, and Kristiina Verro
The Cryosphere, 19, 597–618, https://doi.org/10.5194/tc-19-597-2025, https://doi.org/10.5194/tc-19-597-2025, 2025
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We use three sophisticated climate models to examine extreme precipitation in a critical region of West Antarctica. We found that rainfall probably occurred during the two cases we examined and that it was generated by the interaction of air with steep topography. Our results show that kilometre-scale models are useful tools for exploring extreme precipitation in this region and that more observations of rainfall are needed.
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
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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
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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
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Here, we present an overview of the data generated as part of the North Atlantic Climate System Integrated Study (ACSIS) programme that are available through dedicated repositories at the Centre for Environmental Data Analysis (CEDA; www.ceda.ac.uk) and the British Oceanographic Data Centre (BODC; bodc.ac.uk). The datasets described here cover the North Atlantic Ocean, the atmosphere above (it including its composition), and Arctic sea ice.
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
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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.
Kenza Tazi, Andrew Orr, Javier Hernandez-González, Scott Hosking, and Richard E. Turner
Hydrol. Earth Syst. Sci., 28, 4903–4925, https://doi.org/10.5194/hess-28-4903-2024, https://doi.org/10.5194/hess-28-4903-2024, 2024
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This work aims to improve the understanding of precipitation patterns in High-mountain Asia, a crucial water source for around 1.9 billion people. Through a novel machine learning method, we generate high-resolution precipitation predictions, including the likelihoods of floods and droughts. Compared to state-of-the-art methods, our method is simpler to implement and more suitable for small datasets. The method also shows accuracy comparable to or better than existing benchmark datasets.
Ling Zou, Reinhold Spang, Sabine Griessbach, Lars Hoffmann, Farahnaz Khosrawi, Rolf Müller, and Ines Tritscher
Atmos. Chem. Phys., 24, 11759–11774, https://doi.org/10.5194/acp-24-11759-2024, https://doi.org/10.5194/acp-24-11759-2024, 2024
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This study provided estimates of the occurrence of ice polar stratospheric clouds (PSCs) observed by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) and their connection with temperatures above the frost point (Tice) using a Lagrangian model derived from ERA5. We found that ice PSCs above Tice with temperature fluctuations along the backward trajectory are 33 % in the Arctic and 9 % in the Antarctic. This quantitative assessment enhances our understanding of ice PSCs.
Xavier J. Levine, Ryan S. Williams, Gareth Marshall, Andrew Orr, Lise Seland Graff, Dörthe Handorf, Alexey Karpechko, Raphael Köhler, René R. Wijngaard, Nadine Johnston, Hanna Lee, Lars Nieradzik, and Priscilla A. Mooney
Earth Syst. Dynam., 15, 1161–1177, https://doi.org/10.5194/esd-15-1161-2024, https://doi.org/10.5194/esd-15-1161-2024, 2024
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While the most recent climate projections agree that the Arctic is warming, differences remain in how much and in other climate variables such as precipitation. This presents a challenge for stakeholders who need to develop mitigation and adaptation strategies. We tackle this problem by using the storyline approach to generate four plausible and actionable realisations of end-of-century climate change for the Arctic, spanning its most likely range of variability.
Nicolaj Hansen, Andrew Orr, Xun Zou, Fredrik Boberg, Thomas J. Bracegirdle, Ella Gilbert, Peter L. Langen, Matthew A. Lazzara, Ruth Mottram, Tony Phillips, Ruth Price, Sebastian B. Simonsen, and Stuart Webster
The Cryosphere, 18, 2897–2916, https://doi.org/10.5194/tc-18-2897-2024, https://doi.org/10.5194/tc-18-2897-2024, 2024
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We investigated a melt event over the Ross Ice Shelf. We use regional climate models and a firn model to simulate the melt and compare the results with satellite data. We find that the firn model aligned well with observed melt days in certain parts of the ice shelf. The firn model had challenges accurately simulating the melt extent in the western sector. We identified potential reasons for these discrepancies, pointing to limitations in the models related to representing the cloud properties.
Jan Clemens, Lars Hoffmann, Bärbel Vogel, Sabine Grießbach, and Nicole Thomas
Geosci. Model Dev., 17, 4467–4493, https://doi.org/10.5194/gmd-17-4467-2024, https://doi.org/10.5194/gmd-17-4467-2024, 2024
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Lagrangian transport models simulate the transport of air masses in the atmosphere. For example, one model (CLaMS) is well suited to calculating transport as it uses a special coordinate system and special vertical wind. However, it only runs inefficiently on modern supercomputers. Hence, we have implemented the benefits of CLaMS into a new model (MPTRAC), which is already highly efficient on modern supercomputers. Finally, in extensive tests, we showed that CLaMS and MPTRAC agree very well.
Lars Hoffmann, Kaveh Haghighi Mood, Andreas Herten, Markus Hrywniak, Jiri Kraus, Jan Clemens, and Mingzhao Liu
Geosci. Model Dev., 17, 4077–4094, https://doi.org/10.5194/gmd-17-4077-2024, https://doi.org/10.5194/gmd-17-4077-2024, 2024
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Lagrangian particle dispersion models are key for studying atmospheric transport but can be computationally intensive. To speed up simulations, the MPTRAC model was ported to graphics processing units (GPUs). Performance optimization of data structures and memory alignment resulted in runtime improvements of up to 75 % on NVIDIA A100 GPUs for ERA5-based simulations with 100 million particles. These optimizations make the MPTRAC model well suited for future high-performance computing systems.
Gunter Stober, Sharon L. Vadas, Erich Becker, Alan Liu, Alexander Kozlovsky, Diego Janches, Zishun Qiao, Witali Krochin, Guochun Shi, Wen Yi, Jie Zeng, Peter Brown, Denis Vida, Neil Hindley, Christoph Jacobi, Damian Murphy, Ricardo Buriti, Vania Andrioli, Paulo Batista, John Marino, Scott Palo, Denise Thorsen, Masaki Tsutsumi, Njål Gulbrandsen, Satonori Nozawa, Mark Lester, Kathrin Baumgarten, Johan Kero, Evgenia Belova, Nicholas Mitchell, Tracy Moffat-Griffin, and Na Li
Atmos. Chem. Phys., 24, 4851–4873, https://doi.org/10.5194/acp-24-4851-2024, https://doi.org/10.5194/acp-24-4851-2024, 2024
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On 15 January 2022, the Hunga Tonga-Hunga Ha‘apai volcano exploded in a vigorous eruption, causing many atmospheric phenomena reaching from the surface up to space. In this study, we investigate how the mesospheric winds were affected by the volcanogenic gravity waves and estimated their propagation direction and speed. The interplay between model and observations permits us to gain new insights into the vertical coupling through atmospheric gravity waves.
Irene Bartolomé García, Odran Sourdeval, Reinhold Spang, and Martina Krämer
Atmos. Chem. Phys., 24, 1699–1716, https://doi.org/10.5194/acp-24-1699-2024, https://doi.org/10.5194/acp-24-1699-2024, 2024
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How many ice crystals of each size are in a cloud is a key parameter for the retrieval of cloud properties. The distribution of ice crystals is obtained from in situ measurements and used to create parameterizations that can be used when analyzing the remote-sensing data. Current parameterizations are based on data sets that do not include reliable measurements of small crystals, but in our study we use a data set that includes very small ice crystals to improve these parameterizations.
Reinhold Spang, Rolf Müller, and Alexandru Rap
Atmos. Chem. Phys., 24, 1213–1230, https://doi.org/10.5194/acp-24-1213-2024, https://doi.org/10.5194/acp-24-1213-2024, 2024
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Cirrus clouds play an important role in the radiation budget of the Earth. Despite recent progress in their observation, the radiative impact of ultra-thin cirrus clouds (UTC) in the tropopause region and in the lowermost stratosphere remains poorly constrained. Sensitivity model simulations with different ice parameters provide an uncertainty range for the radiative effect of UTCs. There is a need for better observed UTCs to enable the simulation of their potentially large effect on climate.
Jan Clemens, Bärbel Vogel, Lars Hoffmann, Sabine Griessbach, Nicole Thomas, Suvarna Fadnavis, Rolf Müller, Thomas Peter, and Felix Ploeger
Atmos. Chem. Phys., 24, 763–787, https://doi.org/10.5194/acp-24-763-2024, https://doi.org/10.5194/acp-24-763-2024, 2024
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The source regions of the Asian tropopause aerosol layer (ATAL) are debated. We use balloon-borne measurements of the layer above Nainital (India) in August 2016 and atmospheric transport models to find ATAL source regions. Most air originated from the Tibetan plateau. However, the measured ATAL was stronger when more air originated from the Indo-Gangetic Plain and weaker when more air originated from the Pacific. Hence, the results indicate important anthropogenic contributions to the ATAL.
Abhiraj Bishnoi, Olaf Stein, Catrin I. Meyer, René Redler, Norbert Eicker, Helmuth Haak, Lars Hoffmann, Daniel Klocke, Luis Kornblueh, and Estela Suarez
Geosci. Model Dev., 17, 261–273, https://doi.org/10.5194/gmd-17-261-2024, https://doi.org/10.5194/gmd-17-261-2024, 2024
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We enabled the weather and climate model ICON to run in a high-resolution coupled atmosphere–ocean setup on the JUWELS supercomputer, where the ocean and the model I/O runs on the CPU Cluster, while the atmosphere is running simultaneously on GPUs. Compared to a simulation performed on CPUs only, our approach reduces energy consumption by 45 % with comparable runtimes. The experiments serve as preparation for efficient computing of kilometer-scale climate models on future supercomputing systems.
Bärbel Vogel, C. Michael Volk, Johannes Wintel, Valentin Lauther, Jan Clemens, Jens-Uwe Grooß, Gebhard Günther, Lars Hoffmann, Johannes C. Laube, Rolf Müller, Felix Ploeger, and Fred Stroh
Atmos. Chem. Phys., 24, 317–343, https://doi.org/10.5194/acp-24-317-2024, https://doi.org/10.5194/acp-24-317-2024, 2024
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Over the Indian subcontinent, polluted air is rapidly uplifted to higher altitudes during the Asian monsoon season. We present an assessment of vertical transport in this region using different wind data provided by the European Centre for Medium-Range Weather Forecasts (ECMWF), as well as high-resolution aircraft measurements. In general, our findings confirm that the newest ECMWF reanalysis product, ERA5, yields a better representation of transport compared to the predecessor, ERA-Interim.
Xue Wu, Lars Hoffmann, Corwin J. Wright, Neil P. Hindley, M. Joan Alexander, Silvio Kalisch, Xin Wang, Bing Chen, Yinan Wang, and Daren Lyu
EGUsphere, https://doi.org/10.5194/egusphere-2023-3008, https://doi.org/10.5194/egusphere-2023-3008, 2024
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This study identified a noteworthy time-lagged correlation between hurricane intensity and stratospheric gravity wave intensities during hurricane intensification. Meanwhile, the study reveals distinct frequencies, horizontal wavelengths, and vertical wavelengths in the inner core region during hurricane intensification, offering essential insights for monitoring hurricane intensity via satellite observations of stratospheric gravity waves.
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
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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.
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
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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.
Nicola J. Warwick, Alex T. Archibald, Paul T. Griffiths, James Keeble, Fiona M. O'Connor, John A. Pyle, and Keith P. Shine
Atmos. Chem. Phys., 23, 13451–13467, https://doi.org/10.5194/acp-23-13451-2023, https://doi.org/10.5194/acp-23-13451-2023, 2023
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A chemistry–climate model has been used to explore the atmospheric response to changes in emissions of hydrogen and other species associated with a shift from fossil fuel to hydrogen use. Leakage of hydrogen results in indirect global warming, offsetting greenhouse gas emission reductions from reduced fossil fuel use. To maximise the benefit of hydrogen as an energy source, hydrogen leakage and emissions of methane, carbon monoxide and nitrogen oxides should be minimised.
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
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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.
Marina Friedel, Gabriel Chiodo, Timofei Sukhodolov, James Keeble, Thomas Peter, Svenja Seeber, Andrea Stenke, Hideharu Akiyoshi, Eugene Rozanov, David Plummer, Patrick Jöckel, Guang Zeng, Olaf Morgenstern, and Béatrice Josse
Atmos. Chem. Phys., 23, 10235–10254, https://doi.org/10.5194/acp-23-10235-2023, https://doi.org/10.5194/acp-23-10235-2023, 2023
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Previously, it has been suggested that springtime Arctic ozone depletion might worsen in the coming decades due to climate change, which might counteract the effect of reduced ozone-depleting substances. Here, we show with different chemistry–climate models that springtime Arctic ozone depletion will likely decrease in the future. Further, we explain why models show a large spread in the projected development of Arctic ozone depletion and use the model spread to constrain future projections.
Mingzhao Liu, Lars Hoffmann, Sabine Griessbach, Zhongyin Cai, Yi Heng, and Xue Wu
Geosci. Model Dev., 16, 5197–5217, https://doi.org/10.5194/gmd-16-5197-2023, https://doi.org/10.5194/gmd-16-5197-2023, 2023
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We introduce new and revised chemistry and physics modules in the Massive-Parallel Trajectory Calculations (MPTRAC) Lagrangian transport model aiming to improve the representation of volcanic SO2 transport and depletion. We test these modules in a case study of the Ambae eruption in July 2018 in which the SO2 plume underwent wet removal and convection. The lifetime of SO2 shows highly variable and complex dependencies on the atmospheric conditions at different release heights.
Raghul Parthipan, Hannah M. Christensen, J. Scott Hosking, and Damon J. Wischik
Geosci. Model Dev., 16, 4501–4519, https://doi.org/10.5194/gmd-16-4501-2023, https://doi.org/10.5194/gmd-16-4501-2023, 2023
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How can we create better climate models? We tackle this by proposing a data-driven successor to the existing approach for capturing key temporal trends in climate models. We combine probability, allowing us to represent uncertainty, with machine learning, a technique to learn relationships from data which are undiscoverable to humans. Our model is often superior to existing baselines when tested in a simple atmospheric simulation.
Laura J. Wilcox, Robert J. Allen, Bjørn H. Samset, Massimo A. Bollasina, Paul T. Griffiths, James Keeble, Marianne T. Lund, Risto Makkonen, Joonas Merikanto, Declan O'Donnell, David J. Paynter, Geeta G. Persad, Steven T. Rumbold, Toshihiko Takemura, Kostas Tsigaridis, Sabine Undorf, and Daniel M. Westervelt
Geosci. Model Dev., 16, 4451–4479, https://doi.org/10.5194/gmd-16-4451-2023, https://doi.org/10.5194/gmd-16-4451-2023, 2023
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Changes in anthropogenic aerosol emissions have strongly contributed to global and regional climate change. However, the size of these regional impacts and the way they arise are still uncertain. With large changes in aerosol emissions a possibility over the next few decades, it is important to better quantify the potential role of aerosol in future regional climate change. The Regional Aerosol Model Intercomparison Project will deliver experiments designed to facilitate this.
Lars Hoffmann, Paul Konopka, Jan Clemens, and Bärbel Vogel
Atmos. Chem. Phys., 23, 7589–7609, https://doi.org/10.5194/acp-23-7589-2023, https://doi.org/10.5194/acp-23-7589-2023, 2023
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Atmospheric convection plays a key role in tracer transport in the troposphere. Global meteorological forecasts and reanalyses typically have a coarse spatiotemporal resolution that does not adequately resolve the dynamics, transport, and mixing of air associated with storm systems or deep convection. We discuss the application of the extreme convection parameterization in a Lagrangian transport model to improve simulations of tracer transport from the boundary layer into the free troposphere.
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
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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
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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.
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
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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.
Fouzia Fahrin, Daniel C. Jones, Yan Wu, James Keeble, and Alexander T. Archibald
Atmos. Chem. Phys., 23, 3609–3627, https://doi.org/10.5194/acp-23-3609-2023, https://doi.org/10.5194/acp-23-3609-2023, 2023
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We use a machine learning technique called Gaussian mixture modeling (GMM) to classify vertical ozone profiles into groups based on how the ozone concentration changes with pressure. Even though the GMM algorithm was not provided with spatial information, the classes are geographically coherent. We also detect signatures of tropical broadening in UKESM1 future climate scenarios. GMM may be useful for understanding ozone structures in modeled and observed datasets.
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
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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
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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.
Reimar Bauer, Jens-Uwe Grooß, Jörn Ungermann, May Bär, Markus Geldenhuys, and Lars Hoffmann
Geosci. Model Dev., 15, 8983–8997, https://doi.org/10.5194/gmd-15-8983-2022, https://doi.org/10.5194/gmd-15-8983-2022, 2022
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The Mission Support System (MSS) is an open source software package that has been used for planning flight tracks of scientific aircraft in multiple measurement campaigns during the last decade. Here, we describe the MSS software and its use during the SouthTRAC measurement campaign in 2019. As an example for how the MSS software is used in conjunction with many datasets, we describe the planning of a single flight probing orographic gravity waves propagating up into the lower mesosphere.
Paul Konopka, Mengchu Tao, Marc von Hobe, Lars Hoffmann, Corinna Kloss, Fabrizio Ravegnani, C. Michael Volk, Valentin Lauther, Andreas Zahn, Peter Hoor, and Felix Ploeger
Geosci. Model Dev., 15, 7471–7487, https://doi.org/10.5194/gmd-15-7471-2022, https://doi.org/10.5194/gmd-15-7471-2022, 2022
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Pure trajectory-based transport models driven by meteorology derived from reanalysis products (ERA5) take into account only the resolved, advective part of transport. That means neither mixing processes nor unresolved subgrid-scale advective processes like convection are included. The Chemical Lagrangian Model of the Stratosphere (CLaMS) includes these processes. We show that isentropic mixing dominates unresolved transport. The second most important transport process is unresolved convection.
Jeremy Carter, Amber Leeson, Andrew Orr, Christoph Kittel, and J. Melchior van Wessem
The Cryosphere, 16, 3815–3841, https://doi.org/10.5194/tc-16-3815-2022, https://doi.org/10.5194/tc-16-3815-2022, 2022
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Climate models provide valuable information for studying processes such as the collapse of ice shelves over Antarctica which impact estimates of sea level rise. This paper examines variability across climate simulations over Antarctica for fields including snowfall, temperature and melt. Significant systematic differences between outputs are found, occurring at both large and fine spatial scales across Antarctica. Results are important for future impact assessments and model development.
Flossie Brown, Gerd A. Folberth, Stephen Sitch, Susanne Bauer, Marijn Bauters, Pascal Boeckx, Alexander W. Cheesman, Makoto Deushi, Inês Dos Santos Vieira, Corinne Galy-Lacaux, James Haywood, James Keeble, Lina M. Mercado, Fiona M. O'Connor, Naga Oshima, Kostas Tsigaridis, and Hans Verbeeck
Atmos. Chem. Phys., 22, 12331–12352, https://doi.org/10.5194/acp-22-12331-2022, https://doi.org/10.5194/acp-22-12331-2022, 2022
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Surface ozone can decrease plant productivity and impair human health. In this study, we evaluate the change in surface ozone due to climate change over South America and Africa using Earth system models. We find that if the climate were to change according to the worst-case scenario used here, models predict that forested areas in biomass burning locations and urban populations will be at increasing risk of ozone exposure, but other areas will experience a climate benefit.
Ewa M. Bednarz, Ryan Hossaini, Martyn P. Chipperfield, N. Luke Abraham, and Peter Braesicke
Atmos. Chem. Phys., 22, 10657–10676, https://doi.org/10.5194/acp-22-10657-2022, https://doi.org/10.5194/acp-22-10657-2022, 2022
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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.
Neil P. Hindley, Nicholas J. Mitchell, Neil Cobbett, Anne K. Smith, Dave C. Fritts, Diego Janches, Corwin J. Wright, and Tracy Moffat-Griffin
Atmos. Chem. Phys., 22, 9435–9459, https://doi.org/10.5194/acp-22-9435-2022, https://doi.org/10.5194/acp-22-9435-2022, 2022
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We present observations of winds in the mesosphere and lower thermosphere (MLT) from a recently installed meteor radar on the remote island of South Georgia (54° S, 36° W). We characterise mean winds, tides, planetary waves, and gravity waves in the MLT at this location and compare our measured winds with a leading climate model. We find that the observed wintertime winds are unexpectedly reversed from model predictions, probably because of missing impacts of secondary gravity waves in the model.
Zhongyin Cai, Sabine Griessbach, and Lars Hoffmann
Atmos. Chem. Phys., 22, 6787–6809, https://doi.org/10.5194/acp-22-6787-2022, https://doi.org/10.5194/acp-22-6787-2022, 2022
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Using AIRS and TROPOMI sulfur dioxide retrievals and the Lagrangian transport model MPTRAC, we present an improved reconstruction of injection parameters of the 2019 Raikoke eruption. Reconstructions agree well between using AIRS nighttime and TROPOMI daytime retrievals, showing the potential of our approach to create a long-term volcanic sulfur dioxide inventory from nearly 20 years of AIRS retrievals.
Ling Zou, Sabine Griessbach, Lars Hoffmann, and Reinhold Spang
Atmos. Chem. Phys., 22, 6677–6702, https://doi.org/10.5194/acp-22-6677-2022, https://doi.org/10.5194/acp-22-6677-2022, 2022
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Ice clouds in the stratosphere (SICs) greatly affect the water vapor balance and radiation budget in the upper troposphere and lower stratosphere (UTLS). We quantified the global SICs and analyzed their relationships with tropopause temperature, double tropopauses, UTLS clouds, gravity waves, and stratospheric aerosols. The correlations between SICs and all abovementioned processes indicate that the occurrence of and variability in SICs are spatiotemporally dependent on different processes.
Phoebe Noble, Neil Hindley, Corwin Wright, Chihoko Cullens, Scott England, Nicholas Pedatella, Nicholas Mitchell, and Tracy Moffat-Griffin
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-150, https://doi.org/10.5194/acp-2022-150, 2022
Revised manuscript not accepted
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We use long term radar data and the WACCM-X model to study the impact of dynamical phenomena, including the 11-year solar cycle, ENSO, QBO and SAM, on Antarctic mesospheric winds. We find that in summer, the zonal wind (both observationally and in the model) is strongly correlated with the solar cycle. We also see important differences in the results from the other processes. In addition we find important and large biases in the winter model zonal winds relative to the observations.
Lars Hoffmann, Paul F. Baumeister, Zhongyin Cai, Jan Clemens, Sabine Griessbach, Gebhard Günther, Yi Heng, Mingzhao Liu, Kaveh Haghighi Mood, Olaf Stein, Nicole Thomas, Bärbel Vogel, Xue Wu, and Ling Zou
Geosci. Model Dev., 15, 2731–2762, https://doi.org/10.5194/gmd-15-2731-2022, https://doi.org/10.5194/gmd-15-2731-2022, 2022
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We describe the new version (2.2) of the Lagrangian transport model MPTRAC, which has been ported for application on GPUs. The model was verified by comparing kinematic trajectories and synthetic tracer simulations for the free troposphere and stratosphere from GPUs and CPUs. Benchmarking showed a speed-up of a factor of 16 of GPU-enabled simulations compared to CPU-only runs, indicating the great potential of applying GPUs for Lagrangian transport simulations on upcoming HPC systems.
Lars Hoffmann and Reinhold Spang
Atmos. Chem. Phys., 22, 4019–4046, https://doi.org/10.5194/acp-22-4019-2022, https://doi.org/10.5194/acp-22-4019-2022, 2022
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We present an intercomparison of 2009–2018 lapse rate tropopause characteristics as derived from ECMWF's ERA5 and ERA-Interim reanalyses. Large-scale features are similar, but ERA5 shows notably larger variability, which we mainly attribute to UTLS temperature fluctuations due to gravity waves being better resolved by ECMWF's IFS forecast model. Following evaluation with radiosondes and GPS data, we conclude ERA5 will be a more suitable asset for tropopause-related studies in future work.
Paul F. Baumeister and Lars Hoffmann
Geosci. Model Dev., 15, 1855–1874, https://doi.org/10.5194/gmd-15-1855-2022, https://doi.org/10.5194/gmd-15-1855-2022, 2022
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The efficiency of the numerical simulation of radiative transport is shown on modern server-class graphics cards (GPUs). The low-cost prefactor on GPUs compared to general-purpose processors (CPUs) enables future large retrieval campaigns for multi-channel data from infrared sounders aboard low-orbit satellites. The validated research software JURASSIC is available in the public domain.
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
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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.
Nicolaj Hansen, Sebastian B. Simonsen, Fredrik Boberg, Christoph Kittel, Andrew Orr, Niels Souverijns, J. Melchior van Wessem, and Ruth Mottram
The Cryosphere, 16, 711–718, https://doi.org/10.5194/tc-16-711-2022, https://doi.org/10.5194/tc-16-711-2022, 2022
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We investigate the impact of different ice masks when modelling surface mass balance over Antarctica. We used ice masks and data from five of the most used regional climate models and a common mask. We see large disagreement between the ice masks, which has a large impact on the surface mass balance, especially around the Antarctic Peninsula and some of the largest glaciers. We suggest a solution for creating a new, up-to-date, high-resolution ice mask that can be used in Antarctic modelling.
Anna Vaughan, Will Tebbutt, J. Scott Hosking, and Richard E. Turner
Geosci. Model Dev., 15, 251–268, https://doi.org/10.5194/gmd-15-251-2022, https://doi.org/10.5194/gmd-15-251-2022, 2022
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We develop a new method for climate downscaling, i.e. transforming low-resolution climate model output to high-resolution projections, using a deep-learning model known as a convolutional conditional neural process. This model is shown to outperform an ensemble of baseline methods for downscaling daily maximum temperature and precipitation and provides a powerful new downscaling framework for climate impact studies.
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
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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
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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.
Cited articles
AIRS/Aqua Observations of Gravity Waves, re3data.org – Registry of Research Data Repositories, http://doi.org/10.17616/R34J42, 2020.
Alexander, J. M. and Teitelbaum, H.: Observation and analysis of a large
amplitude mountain wave event over the Antarctic Peninsula, J. Geophys.
Res., 112, D21103, https://doi.org/10.1029/2006JD008368, 2007.
Alexander, S. P., Klekociuk, A. R., Pitts, M. C., McDonald, A. J., and
Arevalo-Torres, A.: The effect of orographic gravity waves on Antarctic
polar stratosphere cloud occurrence and composition, J. Geophys. Res., 116, D06109, https://doi.org/10.1029/2010JD015184, 2011.
Alexander, S. P., Klekociuk, A. R., McDonald, A. J., and Pitts, M. C.:
Quantifying the role of orographic gravity waves on polar stratospheric
cloud occurrence in the Antarctic and the Arctic, J. Geophys. Res., 118,
11493–11507, https://doi.org/10.1002/2013JD020122, 2013.
Alexander, S., Orr, A., Webster, S., and Murphy, D.: Observations and
fine-scale model simulations of gravity waves over Davis, East Antarctica
(69∘ S, 78∘ E), J. Geophys. Res., 122, 7355–7370, https://doi.org/10.1002/2017JD026615, 2017.
Alfred, J., Fromm, M., Bevilacqua, R., Nedoluha, G., Strawa, A., Poole, L., and Wickert, J.: Observations and analysis of polar stratospheric clouds detected by POAM III and SAGE III during the SOLVE II/VINTERSOL campaign in the 2002/2003 Northern Hemisphere winter, Atmos. Chem. Phys., 7, 2151–2163, https://doi.org/10.5194/acp-7-2151-2007, 2007.
Bacmeister, J. T., Schoeberl, M. R., Lait, L. R., Newman, P. A., and Gary,
B.: ER-2 mountain wave encounter over Antarctica: Evidence for blocking,
Geophys. Res. Lett., 17, 81–84, https://doi.org/10.1029/GL017i001p00081,1990.
Bramberger, M., Dörnbrack, A., Bossert, K., Ehard, B., Fritts, D. C., Kaifler, B., Mallaun, C., Orr, A., Pautet, P.-Dominique, Rapp, M., Taylor, M. J., Vosper, S., Williams, B. P., and Witschas, B.: Does strong tropospheric forcing cause large-amplitude mesospheric gravity waves? A DEEPWAVE case study, J. Geophys. Res., 122, 11422–11443, https://doi.org/10.1002/2017JD027371, 2017.
British Antarctic Survey: high resolution radiosonde data from Halley and Rothera stations, NCAS British Atmospheric Data Centre, 2020, http://catalogue.ceda.ac.uk/uuid/37f2bef57e28bcd780a5cbfe077f4bf8, 2008.
Campbell, J. R. and Sassen, K.: Polar stratospheric clouds at the South Pole
from 5 years of continuous lidar data: Macrophysical, optical, and
thermodynamic properties, J. Geophys. Res., 113, D20204,
https://doi.org/10.1029/2007JD009680, 2008.
Carslaw, K., Wirth, M., Tsias, A., Luo, B. P., Dörnbrack, A.,
Leutbecher, M., Volkert, H., Renger, W., Bacmeister, J. T., Reimer, E., and
Peter, Th.: Increased stratospheric ozone depletion due to mountain-induced atmospheric waves, Nature, 391, 675–678, https://doi.org/10.1038/35589, 1998.
Chiodo, G. and Polvani, L. M.: Reduced Southern Hemisphere circulation
response to quadrupled CO2 due to stratospheric ozone feedback,
Geophys. Res. Lett., 44, 465–474, https://doi.org/10.1002/2016GL071011, 2017.
Chipperfield, M. P.: Multiannual simulations with a 3D chemical transport
model, J. Geophys. Res., 104, 1781–1805, https://doi.org/10.1029/98JD02597, 1999.
Dean, S. M., Flowerdew, J., Lawrence, B. N., and Eckermann, S. D.:
Parameterisation of orographic cloud dynamics in a GCM, Clim. Dynam., 28,
581–597, https://doi.org/10.1007/s00382-006-0202-0, 2007.
Dörnbrack, A., Leutbecher, M., Kivi, R., and Kyrö, E.: Mountain
wave-induced record low stratospheric temperatures above northern
Scandinavia, Tellus, 51, 951–963, https://doi.org/10.1034/j.1600-0870.1999.00028.x,
1999.
Dörnbrack, A. and Leutbecher, M.: Relevance of mountain waves for the
formation of polar stratospheric clouds over Scandinavia: A 20-year
climatology, J. Geophys. Res., 106, 1583–1593, https://doi.org/10.1029/2000JD900250,
2001.
Dörnbrack, A., Birner, T., Fix, A., Flentje, H., Meister, A., Schmid,
H., Browell, E. V., and Mahoney, M. J.: Evidence for inertia gravity waves
forming in polar stratospheric clouds over Scandinavia, J. Geophys. Res.,
107, 8287, https://doi.org/10.1029/2001JD000452, 2002.
Eckermann, S. D., Hoffmann, L., Höpfner, M., Wu, D. L., and Alexander,
M. J.: Antarctic NAT PSC belt of June 2003: Observational validation of the
mountain wave seeding hypothesis, Geophys. Res. Lett., 36, L02807,
https://doi.org/10.1029/2008GL036629, 2009.
Eyring, V., Arblaster, J. M., Cionni, I., Sedlácek, J., Perlwitz, J.,
Young, P. J., Bekki, S., Bergmann, D., Cameron-Smith, P., Collins, W. J.,
Faluvegi, G., Gottschaldt, K.-D., Horowitz, L. W., Kinnison, D. E.,
Lamarque, J.-F., Marsh, D. R., Saint-Martin, D., Shindell, D. T., Sudo, K.,
Szopa, S., and Watanabe, S.: Long-term ozone changes and associated climate
impacts in CMIP5 simulations, J. Geophys. Res., 118, 5029–5060, https://doi.org/10.1002/jgrd.50316, 2013.
Fahey, D. W., Kelly, K. K., Kawa, S. R., Tuck, A. F., Loewenstein, M., Chan,
K. R., and Heidt, L. E.: Observations of denitrification and dehydration in
the winter polar stratospheres, Nature, 344, 321–324, https://doi.org/10.1038/344321a0, 1990.
Farman, J., Gardiner, B., and Shanklin, J.: Large losses of total ozone in
Antarctica reveal seasonal ClOx/NOx interaction, Nature,
315, 207–210, https://doi.org/10.1038/315207a0, 1985.
Fretwell, P., Pritchard, H. D., Vaughan, D. G., Bamber, J. L., Barrand, N. E., Bell, R., Bianchi, C., Bingham, R. G., Blankenship, D. D., Casassa, G., Catania, G., Callens, D., Conway, H., Cook, A. J., Corr, H. F. J., Damaske, D., Damm, V., Ferraccioli, F., Forsberg, R., Fujita, S., Gim, Y., Gogineni, P., Griggs, J. A., Hindmarsh, R. C. A., Holmlund, P., Holt, J. W., Jacobel, R. W., Jenkins, A., Jokat, W., Jordan, T., King, E. C., Kohler, J., Krabill, W., Riger-Kusk, M., Langley, K. A., Leitchenkov, G., Leuschen, C., Luyendyk, B. P., Matsuoka, K., Mouginot, J., Nitsche, F. O., Nogi, Y., Nost, O. A., Popov, S. V., Rignot, E., Rippin, D. M., Rivera, A., Roberts, J., Ross, N., Siegert, M. J., Smith, A. M., Steinhage, D., Studinger, M., Sun, B., Tinto, B. K., Welch, B. C., Wilson, D., Young, D. A., Xiangbin, C., and Zirizzotti, A.: Bedmap2: improved ice bed, surface and thickness datasets for Antarctica, The Cryosphere, 7, 375–393, https://doi.org/10.5194/tc-7-375-2013, 2013.
Goff, J. A.: Saturation pressure of water on the new Kelvin temperature scale, Trans. Am. Soc. Heating and Vent. Eng., 63, 347–354, 1957.
Hanson, D. and Mauersberger, K.: Laboratory studies of the nitric acid
trihydrate: implications for the south polar stratosphere, Geophys. Res. Lett., 15, 855–858, https://doi.org/10.1029/GL015i008p00855, 1988.
Hersbach, H., Bell, B., Berrisford, P., Hirahara, S., Horányi, A., Joaquín, M.-S., 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., 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.
Hewitt, H. T., Copsey, D., Culverwell, I. D., Harris, C. M., Hill, R. S. R., Keen, A. B., McLaren, A. J., and Hunke, E. C.: Design and implementation of the infrastructure of HadGEM3: the next-generation Met Office climate modelling system, Geosci. Model Dev., 4, 223–253, https://doi.org/10.5194/gmd-4-223-2011, 2011.
Hoffmann, L., Xue, X., and Alexander, M. J.: A global view of stratospheric
gravity wave hotspots located with Atmospheric Infrared Sounder
observations, J. Geophys. Res., 118, 416–434, https://doi.org/10.1029/2012JD018658,
2013.
Hoffmann, L., Grimsdell, A. W., and Alexander, M. J.: Stratospheric gravity waves at Southern Hemisphere orographic hotspots: 2003–2014 AIRS/Aqua observations, Atmos. Chem. Phys., 16, 9381–9397, https://doi.org/10.5194/acp-16-9381-2016, 2016.
Hoffmann, L., Spang, R., Orr, A., Alexander, M. J., Holt, L. A., and Stein, O.: A decadal satellite record of gravity wave activity in the lower stratosphere to study polar stratospheric cloud formation, Atmos. Chem. Phys., 17, 2901–2920, https://doi.org/10.5194/acp-17-2901-2017, 2017.
Iglesias-Suarez, F., Young, P. J., and Wild, O.: Stratospheric ozone change and related climate impacts over 1850–2100 as modelled by the ACCMIP ensemble, Atmos. Chem. Phys., 16, 343–363, https://doi.org/10.5194/acp-16-343-2016, 2016.
Keeble, J., Braesicke, P., Abraham, N. L., Roscoe, H. K., and Pyle, J. A.: The impact of polar stratospheric ozone loss on Southern Hemisphere stratospheric circulation and climate, Atmos. Chem. Phys., 14, 13705–13717, https://doi.org/10.5194/acp-14-13705-2014, 2014.
Kruse, C. G., Smith, R. B., and Eckermann, S. D.: The midlatitude
lower-stratospheric mountain wave “valve layer”, J. Atmos. Sci., 73,
5081–5100, https://doi.org/10.1175/JAS-D-16-0173.1, 2016.
Marti, J. and Mauersberger, K.: A survey and new measurements of ice vapour
pressure at temperatures between 170 and 250 K, Geophys. Res. Lett., 20,
363–366, https://doi.org/10.1029/93GL00105, 1993.
McDonald, A. J., George, S. E., and Woollands, R. M.: Can gravity waves significantly impact PSC occurrence in the Antarctic?, Atmos. Chem. Phys., 9, 8825–8840, https://doi.org/10.5194/acp-9-8825-2009, 2009.
McLandress, C., Jonsson, A. I., Plummer, D. A., Reader, M. C., Scinocca, J.
F., and Shepherd, T. G.: Separating the dynamical effects of climate change
and ozone depletion, Part I: Southern Hemisphere stratosphere, J. Climate,
23, 5002–5020, https://doi.org/10.1175/2010JCLI3586.1, 2010.
Moffat-Griffin, T., Hibbins, R. E., Jarvis, M. J., and Colwell, S. R.:
Seasonal variations of gravity wave activity in the lower stratosphere over
an Antarctic Peninsula station, J. Geophys. Res., 116, D14111,
https://doi.org/10.1029/2010JD015349, 2011.
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.
Noel, V., Hertzog, A., and Chepfer, H.: CALIPSO observations of wave-induced
PSCs with near-unity optical depth over Antarctica in 2006–2007, J.
Geophys. Res., 114, D05202, https://doi.org/10.1029/2008JD010604, 2009.
Orr, A., Marshall, G., Hunt, J. C. R., Sommeria, J., Wang, C., van Lipzig,
N., Cresswell, D., and King, J. C.: Characteristics of airflow over the
Antarctic Peninsula and its response to recent strengthening of westerly
circumpolar winds, J. Atmos. Sci., 65, 1396–1413,
https://doi.org/10.1175/2007JAS2498.1, 2008.
Orr, A., Bracegirdle, T. J., Hoskings, J. S., Jung, T., Haigh, J. D.,
Phillips, T., and Feng, W.: Possible dynamical mechanisms for Southern
Hemisphere climate change due to the ozone hole, J. Atmos. Sci., 69,
2917–2932, https://doi.org/10.1175/JAS-D-11-0210.1, 2012.
Orr, A., Hosking, J. S., Hoffmann, L., Keeble, J., Dean, S. M., Roscoe, H. K., Abraham, N. L., Vosper, S., and Braesicke, P.: Inclusion of mountain-wave-induced cooling for the formation of PSCs over the Antarctic Peninsula in a chemistry–climate model, Atmos. Chem. Phys., 15, 1071–1086, https://doi.org/10.5194/acp-15-1071-2015, 2015.
Pawson, S., Naujokat, B., and Labitzke, K.: On the polar stratospheric cloud
formation potential of the northern stratosphere, J. Geophys. Res., 100,
23215–23225, https://doi.org/10.1029/95JD01918, 1995.
Plougonven, R., Hertzog, A., and Teitelbaum, H.: Observations and
simulations of large-amplitude mountain wave breaking over the Antarctic
Peninsula, J. Geophys. Res., 113, D16113, https://doi.org/10.1029/2007JD009739, 2008.
Plougonven, R., Hertzog, A., and Guez, L.: Gravity waves over Antarctica and
the Southern Ocean: consistent momentum fluxes in mesoscale simulations and
stratospheric balloon observations, Q. J. Roy. Meteor. Soc., 139, 101–118,
https://doi.org/10.1002/qj.1965, 2012.
Polvani, L. M., Waugh, D. W., Correa, G. J. P., and Son, S.-W.:
Stratospheric ozone depletion: The main driver of twentieth-century
atmospheric circulation changes in the Southern Hemisphere, J. Climate,
24, 795–812, https://doi.org/10.1175/2010JCLI3772.1, 2011.
Pope, J. O., Orr, A., Marshall, G. J., and Abraham, N. L.: Non‐additive response of the high‐latitude Southern Hemisphere climate to aerosol forcing in a climate model with interactive chemistry. Atmos Sci Lett. e1004, https://doi.org/10.1002/asl.1004, 2020.
Preusse, P., Dörnbrack, A., Eckermann, S. D., Riese, M., Schaeler, B., Bacmeister, J. T., Broutman, D., and Grossmann, K. U.: Space‐based measurements of stratospheric mountain waves by CRISTA 1, sensitivity, analysis method, and a case study, J. Geophys. Res., 107, 8178, https://doi.org/10.1029/2001JD000699, 2002.
Previdi, M. and Polvani, L. M.: Climate system response to stratospheric
ozone depletion and recovery, Q. J. Roy. Meteor. Soc., 140, 2401–2419, https://doi.org/10.1002/qj.2330, 2014.
Sato, K., Tateno, S., Watanabe, S., and Kawatani, Y.: Gravity wave
characteristics in the Southern Hemisphere revealed by a high-resolution
middle-atmosphere general circulation model, J. Atmos. Sci., 69, 1378–1396,
https://doi.org/10.1175/JAS-D-11-0101.1, 2012.
Schröter, J., Rieger, D., Stassen, C., Vogel, H., Weimer, M., Werchner, S., Förstner, J., Prill, F., Reinert, D., Zängl, G., Giorgetta, M., Ruhnke, R., Vogel, B., and Braesicke, P.: ICON-ART 2.1: a flexible tracer framework and its application for composition studies in numerical weather forecasting and climate simulations, Geosci. Model Dev., 11, 4043–4068, https://doi.org/10.5194/gmd-11-4043-2018, 2018.
Solomon, S.: Stratospheric ozone depletion: A review of concepts and
history, Rev. Geophys., 37, 275–316, https://doi.org/10.1029/1999RG900008, 1999.
Solomon, S., Garcia, R. R., Rowland, F. S., and Wuebbles, D. J.: On the
depletion of Antarctic ozone, Nature, 321, 755–758, 1986.
Son, S.-W., Gerber, E. P., Perlwitz, J., Polvani, L. M., Gillett, N. P.,
Seo, K.-H., Eyring, V., Shepherd, T. G., Waugh, D., Akiyoshi, H., Austin,
J., Baumgaertner, A., Bekki, S., Braesicke, P., Bruhl, C., Butchart, N.,
Chipperfield, M. P., Cugnet, D., Dameris, M., Dhomse, S., Frith, S., Garny,
H., Garcia, R., Hardiman, S, C., Jockel, P., Lamarque, J. F., Mancini, E.,
Marchand, M., Michou, M., Nakamura, T., Morgenstern, O., Pitari, G.,
Plummer, D. A., Pyle, J., Rozanov, E., Scinocca, J. F., Shibata, K., Smale,
D., Teyssedre, H., Tian, W., and Yamashita, Y.: Impact of stratospheric
ozone on Southern Hemisphere circulation change: a multimodel assessment, J.
Geophys. Res., 115, D00M07, https://doi.org/10.1029/2010JD014271, 2010.
Spang, R., Hoffmann, L., Müller, R., Grooß, J.-U., Tritscher, I., Höpfner, M., Pitts, M., Orr, A., and Riese, M.: A climatology of polar stratospheric cloud composition between 2002 and 2012 based on MIPAS/Envisat observations, Atmos. Chem. Phys., 18, 5089–5113, https://doi.org/10.5194/acp-18-5089-2018, 2018.
Teitelbaum, H., Moustaoui, M., and Fromm, M.: Exploring polar stratospheric
cloud and ozone minihole formation: The primary importance of synoptic-scale
flow perturbations, J. Geophys. Res., 106, 28173–28188, https://doi.org/10.1029/2000JD000065, 2001.
Thompson, D. W. J. and Solomon, S.: Interpretation of recent southern
hemisphere climate change, Science, 296, 895–899, https://doi.org/10.1126/science.1069270, 2002.
Thompson, D. W. J. and Wallace, J. M.: Annular modes in the extratropical
circulation, Part I: Month-to-month variability, J. Climate, 13, 1000–1016,
https://doi.org/10.1175/1520-0442(2000)013<1000:AMITEC>2.0.CO;2, 2000.
Wu, D. L. and Eckermann, S. D.: Global gravity wave variances from Aura MLS:
Characteristics and interpretation, J. Atmos. Sci., 65, 3695–3718,
https://doi.org/10.1175/2008JAS2489.1, 2008.
Short summary
Polar stratospheric clouds (PSCs) are clouds found in the Antarctic winter stratosphere and are implicated in the formation of the ozone hole. These clouds can sometimes be formed or enhanced by mountain waves, formed as air passes over hills or mountains. However, this important mechanism is missing in coarse-resolution climate models, limiting our ability to simulate ozone. This study examines an attempt to include the effects of mountain waves and their impact on PSCs and ozone.
Polar stratospheric clouds (PSCs) are clouds found in the Antarctic winter stratosphere and are...
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