Articles | Volume 26, issue 9
https://doi.org/10.5194/acp-26-6283-2026
© Author(s) 2026. 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-26-6283-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| Highlight paper
| 
11 May 2026
Research article | Highlight paper |
| 11 May 2026
| 11 May 2026
Continental and marine source regions contributing to the outflow of the Asian summer monsoon anticyclone during the PHILEAS campaign in summer 2023
Institute of Climate and Energy Systems (ICE-4), Forschungszentrum Jülich, Jülich, Germany
Valentin Lauther
Institute for Atmospheric and Environmental Research, University of Wuppertal, Wuppertal, Germany
Franziska Köllner
Johannes Gutenberg University of Mainz, Institute for Atmospheric Physics, Mainz, Germany
Max Planck Institute for Chemistry, Mainz, Germany
Fatih Ekinci
Johannes Gutenberg University of Mainz, Institute for Atmospheric Physics, Mainz, Germany
Max Planck Institute for Chemistry, Mainz, Germany
Institute for Applied Geosciences (Environmental Mineralogy), Technical University of Darmstadt, Darmstadt, Germany
Christian Rolf
Institute of Climate and Energy Systems (ICE-4), Forschungszentrum Jülich, Jülich, Germany
Johannes Strobel
Institute for Atmospheric and Environmental Research, University of Wuppertal, Wuppertal, Germany
Ronja van Luijt
Institute for Atmospheric and Environmental Research, University of Wuppertal, Wuppertal, Germany
C. Michael Volk
Institute for Atmospheric and Environmental Research, University of Wuppertal, Wuppertal, Germany
Stephan Borrmann
Johannes Gutenberg University of Mainz, Institute for Atmospheric Physics, Mainz, Germany
Max Planck Institute for Chemistry, Mainz, Germany
Antonis Dragoneas
Max Planck Institute for Chemistry, Mainz, Germany
Oliver Eppers
Max Planck Institute for Chemistry, Mainz, Germany
Sergej Molleker
Max Planck Institute for Chemistry, Mainz, Germany
Peter Hoor
Johannes Gutenberg University of Mainz, Institute for Atmospheric Physics, Mainz, Germany
Linda Ort
Max Planck Institute for Chemistry, Mainz, Germany
Franziska Weyland
Johannes Gutenberg University of Mainz, Institute for Atmospheric Physics, Mainz, Germany
Andreas Zahn
Institute of Meteorology and Climate Research, Karlsruhe Institute of Technology, Karlsruhe, Germany
Jan Clemens
Institute of Climate and Energy Systems (ICE-4), Forschungszentrum Jülich, Jülich, Germany
Gebhard Günther
Institute of Climate and Energy Systems (ICE-4), Forschungszentrum Jülich, Jülich, Germany
Oleh Kachula
Institute of Climate and Energy Systems (ICE-4), Forschungszentrum Jülich, Jülich, Germany
Rolf Müller
Institute of Climate and Energy Systems (ICE-4), Forschungszentrum Jülich, Jülich, Germany
Felix Ploeger
Institute of Climate and Energy Systems (ICE-4), Forschungszentrum Jülich, Jülich, Germany
Institute for Atmospheric and Environmental Research, University of Wuppertal, Wuppertal, Germany
Martin Riese
Institute of Climate and Energy Systems (ICE-4), Forschungszentrum Jülich, Jülich, Germany
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Gerald Wetzel, Felix Friedl-Vallon, Norbert Glatthor, Jens-Uwe Grooß, Thomas Gulde, Michael Höpfner, Sören Johansson, Farahnaz Khosrawi, Oliver Kirner, Anne Kleinert, Erik Kretschmer, Guido Maucher, Hans Nordmeyer, Hermann Oelhaf, Johannes Orphal, Christof Piesch, Björn-Martin Sinnhuber, Jörn Ungermann, and Bärbel Vogel
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Athulya Saiprakash, Martina Krämer, Christian Rolf, Jérôme Riedi, and Odran Sourdeval
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This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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Noelia R. Benavente, Santiago Botía, Luciana V. Rizzo, Angel Vara-Vela, Paulo Artaxo, Hella van Asperen, Felipe Santos da Silva, Flavio A. F. D'Oliveira, Horst Fischer, Michał Gałkowski, Theo Glauch, Alice Henkes, David Ho, Cléo Q. Dias-Júnior, Amauri C. P. Junior, Julia Marshall, Linda Ort, Ben-Hur M. Portella, and Luiz A. T. Machado
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This study shows that aerosol transported from the Asian summer monsoon region can substantially alter the background composition of the extratropical lower stratosphere. Aircraft-based measurements and model simulations reveal a strong increase of ammonium nitrate aerosol from summer to autumn 2023 caused by transport of young air masses from South and East Asia. These particles can persist for months and undergo chemical aging.
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Atmos. Chem. Phys., 26, 3637–3652, https://doi.org/10.5194/acp-26-3637-2026, https://doi.org/10.5194/acp-26-3637-2026, 2026
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During the PHILEAS aircraft campaign a self-matching experiment was conducted to study the mixing of Asian Summer monsoon air into the UTLS. We present the first 3-D tomographic observations of this mixing for multiple trace gas species. We use advanced clustering to identify the types of air and their transport pathways. Simulations of surface-origin tracers link several of these air types to different source regions. This study shows how pollutants of the monsoon enter the stratosphere.
Manuel Moser, Christiane Voigt, Oliver Eppers, Johannes Lucke, Elena De La Torre Castro, Johanna Mayer, Regis Dupuy, Guillaume Mioche, Olivier Jourdan, Hans-Christian Clemen, Johannes Schneider, Philipp Joppe, Stephan Mertes, Bruno Wetzel, Stephan Borrmann, Marcus Klingebiel, Mario Mech, Christof Lüpkes, Susanne Crewell, André Ehrlich, Andreas Herber, and Manfred Wendisch
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In this study we analyzed Arctic mixed-phase clouds using airborne in-situ measurements in spring 2022. Based on microphysical properties, we show that within these clouds a distinction must be made between classic mixed-phase clouds and a mixed-phase haze regime. Instead of supercooled droplets, the haze regime contains large wet sea salt aerosols. These findings improve our understanding of Arctic low-level cloud processes.
Sylvia C. Sullivan, Aiko Voigt, Edgardo Sepúlveda Araya, Silvia Bucci, Annette Miltenberger, Meredith K. Kupinski, Christian Rolf, and Martina Krämer
Atmos. Chem. Phys., 26, 1685–1698, https://doi.org/10.5194/acp-26-1685-2026, https://doi.org/10.5194/acp-26-1685-2026, 2026
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We assess the temperature, moisture, and dynamics in the upper troposphere-lower stratosphere simulated over South Asia in a high-resolution model relative to aircraft data. The lower stratosphere tends to be too warm, too dry, and too quiescent in the model, and as a result, too few ice clouds are predicted to form there. These biases could affect radiative balance and circulation in other areas also, as significant upward transport of moisture and pollutants occurs during the Asian monsoon.
Irina Petropavlovskikh, Martine De Mazière, Anne M. Thompson, Jeannette D. Wild, James W. Hannigan, Henry B. Selkirk, Reem A. Hannum, Wolfgang Steinbrecht, Jean-Christopher Lambert, Roeland Van Malderen, Elizabeth Asher, Raul R. Cordero, Sophie Godin-Beekmann, Daan Hubert, Sergey Khaykin, Karin Kreher, Thierry Leblanc, Emmanuel Mahieu, Eliane Maillard Barras, Glen McConville, Gerald Nedoluha, Ivan Ortega, Alberto Redondas Marrero, Gunther Seckmeyer, Ryan M. Stauffer, Sarah A. Strode, Kim Strong, Takafumi Sugita, Michel Van Roozendael, Voltaire Velazco, Corinne Vigouroux, and Baerbel Vogel
EGUsphere, https://doi.org/10.5194/egusphere-2025-6557, https://doi.org/10.5194/egusphere-2025-6557, 2026
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This introduction to the special issue "Achievements and perspectives of the Network for the Detection of Atmospheric Composition Change after 35 years of operation” provides an overview of important research findings achieved under the NDACC objectives. The future of NDACC is discussed in the light of the evolution of the scientific questions, evolving collaborations with partners and Cooperating Networks, and the current landscape of gaps in satellite and ground-based observations.
Madhuri Umbarkar, Daniel Kunkel, Annette Miltenberger, Hans-Christoph Lachnitt, Thorsten Kaluza, Cornelis Schwenk, and Peter Hoor
EGUsphere, https://doi.org/10.5194/egusphere-2025-5142, https://doi.org/10.5194/egusphere-2025-5142, 2025
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We present an extratropical cyclone case study over the North Atlantic, focusing on the role of atmospheric gravity waves (GWs) in the generation of enhanced vertical wind shear and (clear-air) turbulence, as well as their impact on tracers distribution in the lowermost stratosphere. Our research suggests the GW related processes should be considered as a key for UTLS transport and mixing and as an important candidate for the interpretation of CAT, that appear to emanate from GW-induced shear.
Linda Smoydzin, Vera Bense, Heiko Bozem, Philipp Joppe, Daniel Kunkel, Hans-Christoph Lachnitt, Holger Tost, Andreas Zahn, Helmut Ziereis, Martin Riese, and Peter Hoor
EGUsphere, https://doi.org/10.5194/egusphere-2025-5372, https://doi.org/10.5194/egusphere-2025-5372, 2025
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During a research flight in early October elevated upper tropospheric mixing ratios of CO, NO, NOy and O3 were observed over a distance of more than 1000 km east of the Brasilian coast. Ozone mixing ratios are 20–40 ppbv higher than during a flight in early September. By combining aircraft observations with model simulations we find that ozone production from biomass burning over Amazonia caused predominantly the ozone enhancements which have a local effect on the radiative forcing of 50 mWm−2.
Paul Konopka, Felix Ploeger, Francesco D'Amato, Teresa Campos, Marc von Hobe, Shawn B. Honomichl, Peter Hoor, Laura L. Pan, Michelle L. Santee, Silvia Viciani, Kaley A. Walker, and Michaela I. Hegglin
Atmos. Chem. Phys., 25, 17973–17996, https://doi.org/10.5194/acp-25-17973-2025, https://doi.org/10.5194/acp-25-17973-2025, 2025
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We present an improved version of the Chemical Lagrangian Model of the Stratosphere (CLaMS-3.0), which better represents transport from the lower atmosphere to the upper troposphere and lower stratosphere. By refining grid resolution and improving convection representation, the model more accurately simulates carbon monoxide transport. Comparisons with satellite and in situ observations highlight its ability to capture seasonal variations and improve our understanding of atmospheric transport.
Patrick Konjari, Christian Rolf, Martina Krämer, Armin Afchine, Nicole Spelten, Irene Bartolome Garcia, Annette Miltenberger, Nicolas Emig, Philipp Joppe, Johannes Schneider, Yun Li, Andreas Petzold, Heiko Bozem, and Peter Hoor
Atmos. Chem. Phys., 25, 18031–18050, https://doi.org/10.5194/acp-25-18031-2025, https://doi.org/10.5194/acp-25-18031-2025, 2025
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We investigated how a powerful storm over southern Sweden in June 2024 transported ice particles and moist air into the normally dry stratosphere. We observed unusually high water vapor and ice levels up to 1.5 kilometers above the tropopause. Although the extra water vapor lasted only a few days to weeks, it shows how such storms can temporarily alter the upper atmosphere’s composition.
Anna Breuninger, Philipp Joppe, Jonas Wilsch, Cornelis Schwenk, Heiko Bozem, Nicolas Emig, Laurin Merkel, Rainer Rossberg, Timo Keber, Arthur Kutschka, Philipp Waleska, Stefan Hofmann, Sarah Richter, Florian Ungeheuer, Konstantin Dörholt, Thorsten Hoffmann, Annette Miltenberger, Johannes Schneider, Peter Hoor, and Alexander L. Vogel
Atmos. Chem. Phys., 25, 16533–16551, https://doi.org/10.5194/acp-25-16533-2025, https://doi.org/10.5194/acp-25-16533-2025, 2025
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This study investigates molecular organic aerosol composition in the upper troposphere and lower stratosphere from an airborne campaign over Central Europe in summer 2024. Via ultra-high-performance liquid chromatography and high-resolution mass spectrometry of tropospheric and stratospheric filter samples, we identified various organic compounds. Our findings underscore the significant cross-tropopause transport of biogenic secondary organic aerosol and anthropogenic pollutants.
Heiko Bozem, Philipp Joppe, Yun Li, Nicolas Emig, Armin Afchine, Anna Breuninger, Joachim Curtius, Stefan Hofmann, Sadath Ismayil, Konrad Kandler, Daniel Kunkel, Arthur Kutschka, Hans-Christoph Lachnitt, Andreas Petzold, Sarah Richter, Timo Röschenthaler, Christian Rolf, Lisa Schneider, Johannes Schneider, Alexander Vogel, and Peter Hoor
Atmos. Meas. Tech., 18, 6545–6568, https://doi.org/10.5194/amt-18-6545-2025, https://doi.org/10.5194/amt-18-6545-2025, 2025
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Deployed on a Learjet as a tandem measurement platform during the TPEx I (TropoPause composition gradients and mixing Experiment) campaign in June 2024, the new TPC-TOSS (TropoPause Composition Towed Sensor Shuttle) system delivers high-resolution in situ data on ozone, aerosol, and key meteorological parameters. Laboratory and in-flight tests confirmed its precision and stability. Observed gradients near the tropopause reveal active mixing and transport processes in the tropopause region.
Oleh Kachula, Bärbel Vogel, Gebhard Günther, and Rolf Müller
Atmos. Chem. Phys., 25, 15171–15195, https://doi.org/10.5194/acp-25-15171-2025, https://doi.org/10.5194/acp-25-15171-2025, 2025
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We propose a novel method to define the boundary of the Asian summer monsoon anticyclone (ASMA) and provide the inter-annual and intra-seasonal analyses based on 44 years (1980–2023) and highlight individual years – 2017, 2022 and 2023 during which aircraft campaigns StratoClim, ACCLIP and PHILEAS took place respectively. Our method shows consistent results with previous studies but also provide new information about possible bimodality of the ASMA and inter-annual decrease of the ASMA area.
Philipp Joppe, Johannes Schneider, Jonas Wilsch, Heiko Bozem, Anna Breuninger, Joachim Curtius, Martin Ebert, Nicolas Emig, Peter Hoor, Sadath Ismayil, Konrad Kandler, Daniel Kunkel, Isabel Kurth, Hans-Christoph Lachnitt, Yun Li, Annette Miltenberger, Sarah Richter, Christian Rolf, Lisa Schneider, Cornelis Schwenk, Nicole Spelten, Alexander L. Vogel, Yafang Cheng, and Stephan Borrmann
Atmos. Chem. Phys., 25, 15077–15103, https://doi.org/10.5194/acp-25-15077-2025, https://doi.org/10.5194/acp-25-15077-2025, 2025
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We show measurements of a filament with biomass burning influence transported by a warm conveyor belt (WCB) into the tropopause region over Europe. The pollution originates from Canadian forest fires and is transported in the lower troposphere towards Europe. The WCB transport is followed by mixing with air masses of stratospheric chemical signatures. We hypothesize that this mixing leads to a change in the vertical gradient of the potential temperature.
Linda Ort, Andrea Pozzer, Peter Hoor, Florian Obersteiner, Andreas Zahn, Thomas B. Ryerson, Chelsea R. Thompson, Jeff Peischl, Róisín Commane, Bruce Daube, Ilann Bourgeois, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 25, 14987–15007, https://doi.org/10.5194/acp-25-14987-2025, https://doi.org/10.5194/acp-25-14987-2025, 2025
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This study investigates the role of lightning emissions on the O3–CO ratio in the northern subtropics. We used in situ observations and a global circulation model to show an effect of up to 40 % onto the subtropical O3–CO ratio by tropical air masses transported via the Hadley cell. This influence of lightning emissions and its photochemistry has a global effect on trace and greenhouse gases and needs to be considered for global chemical distributions.
Frederik Harzer, Hella Garny, Felix Ploeger, J. Moritz Menken, and Thomas Birner
Atmos. Chem. Phys., 25, 14909–14921, https://doi.org/10.5194/acp-25-14909-2025, https://doi.org/10.5194/acp-25-14909-2025, 2025
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We study ozone transport in the extratropical lowermost stratosphere using potential temperature as vertical coordinate, thereby distinguishing adiabatic and diabatic processes. We find that on top of known dominant transport processes (quasi-horizontal mixing, slow diabatic descent) vertical mixing plays an important role near the tropopause. Our findings are relevant for understanding ozone's role in climate including its imprint on tropospheric ozone via stratosphere-troposphere air exchange.
Hongyue Wang, Mijeong Park, Mengchu Tao, Cristina Peña-Ortiz, Nuria P. Plaza-Martin, Felix Ploeger, and Paul Konopka
Atmos. Chem. Phys., 25, 14703–14718, https://doi.org/10.5194/acp-25-14703-2025, https://doi.org/10.5194/acp-25-14703-2025, 2025
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We investigate how water vapor in the upper atmosphere gains moisture during the Asian and North American monsoons using a simplified modeling approach. Our results show that the Asian monsoon is mainly controlled by large-scale temperature, whereas the North American monsoon may be more influenced by convective moistening. These differences point to distinct mechanisms shaping moisture transport in the two monsoon systems.
Sophie Bauchinger, Andreas Engel, Markus Jesswein, Timo Keber, Harald Bönisch, Florian Obersteiner, Andreas Zahn, Nicolas Emig, Peter Hoor, Hans-Christoph Lachnitt, Franziska Weyland, Linda Ort, and Tanja J. Schuck
Atmos. Chem. Phys., 25, 14167–14186, https://doi.org/10.5194/acp-25-14167-2025, https://doi.org/10.5194/acp-25-14167-2025, 2025
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We compared different ways to define the upper barrier of the troposphere in the extra-tropics, the “tropopause”. By analysing ozone distributions sorted by different definitions, we found that the traditional temperature-based tropopause works less well than dynamic or tracer-based definitions. We saw a sharper transition of ozone across the tropopause using a higher value of potential vorticity than often used and recommend this value for future studies of exchange processes in this region.
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.
Benjamin Weyland, Simon Rosanka, Domenico Taraborrelli, Birger Bohn, Andreas Zahn, Florian Obersteiner, Eric Förster, Mariano Mertens, Patrick Jöckel, Helmut Ziereis, Katharina Kaiser, Horst Fischer, John N. Crowley, Nijing Wang, Achim Edtbauer, Jonathan Williams, Maria Dolores Andrés Hernández, John P. Burrows, Flora Kluge, Meike Rotermund, Andre Butz, and Klaus Pfeilsticker
EGUsphere, https://doi.org/10.5194/egusphere-2025-5085, https://doi.org/10.5194/egusphere-2025-5085, 2025
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The destruction by sunlight of nitrous acid (HONO) produces the so-called detergent of the atmosphere. HONO has been measured in concentrations which exceed predictions based on known chemistry for decades. Several reactions have been proposed which may explain this excess HONO. This study reports on airborne measurements of HONO; the observations exceed predictions and form a C-shaped profile in the troposphere. Together with a host of other measurements, various reactions are investigated.
Nicolas Emig, Annette K. Miltenberger, Peter M. Hoor, and Andreas Petzold
Atmos. Chem. Phys., 25, 13077–13101, https://doi.org/10.5194/acp-25-13077-2025, https://doi.org/10.5194/acp-25-13077-2025, 2025
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This study presents in situ observations of cirrus occurrence from aircraft measurements in the extratropical transition layer (ExTL) using simultaneous measurements from two platforms. Lagrangian diagnostics based on high-resolution ICON simulations show long residence times of the cirrus in stratospheric air, allowing us to separate different diabatic processes during transit. The findings suggest that radiative diabatic cloud processes significantly impact the tropopause thermodynamic structure.
Chun Hang Chau, Peter Hoor, and Holger Tost
Atmos. Chem. Phys., 25, 13123–13140, https://doi.org/10.5194/acp-25-13123-2025, https://doi.org/10.5194/acp-25-13123-2025, 2025
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This study examines how the turbulence in the upper troposphere/lower stratosphere (UTLS) could modify the tracer distribution under different situations. Using a multi-scale chemistry model with a novel diagnostic, we found that both the pre-existing tracer gradient and the dynamical and thermodynamical forcing play a role in modifying the tracer distribution. These results allow further research on the UTLS turbulent mixing and its implications for the climate system.
Rasul Baikhadzhaev, Felix Ploeger, Peter Preusse, Manfred Ern, and Thomas Birner
Atmos. Chem. Phys., 25, 12753–12777, https://doi.org/10.5194/acp-25-12753-2025, https://doi.org/10.5194/acp-25-12753-2025, 2025
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Across four reanalyses, the shallow branch of the stratospheric overturning circulation was found to be driven by planetary waves 1 to 3, and the deep branch of the circulation was found to be driven by smaller-scale waves (wave 4 and higher). However, the height of the level separating the branches is dependent on the reanalysis considered. Thus, using the appropriate separation levels in model inter-comparisons could reduce the spread between models regarding climatology and trends in the circulation.
Rolf Müller, Lennart Bengtsson, John Birks, John Burrows, Ruprecht Jaenicke, and Richard S. Stolarski
Hist. Geo Space. Sci., 16, 31–40, https://doi.org/10.5194/hgss-16-31-2025, https://doi.org/10.5194/hgss-16-31-2025, 2025
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This paper reports a few anecdotes from the life of Paul J. Crutzen that were contributed by friends and colleagues. Taken together, these anecdotes should shed some light on the person that Paul was, as this is perhaps sometimes obscured when focusing solely on his many scientific achievements.
Johannes Schneider, Christiane Schulz, Florian Rubach, Anna Ludwig, Jonas Wilsch, Philipp Joppe, Christian Gurk, Sergej Molleker, Laurent Poulain, Florian Obersteiner, Torsten Gehrlein, Harald Bönisch, Andreas Zahn, Peter Hoor, Nicolas Emig, Heiko Bozem, Stephan Borrmann, and Markus Hermann
Atmos. Meas. Tech., 18, 5103–5128, https://doi.org/10.5194/amt-18-5103-2025, https://doi.org/10.5194/amt-18-5103-2025, 2025
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An instrumented container laboratory is operated on regular commercial passenger flights to obtain a long-term representative dataset on the composition of the upper troposphere and lower stratosphere. Here we report on the development of a fully automated aerosol mass spectrometer for this project. We present technical specifications, necessary modifications for the automation, instrument calibration and comparisons, detection limits, and the first in-flight data.
Martanda Gautam, Alexander Theis, Jackson Seymore, Moritz Hey, Stephan Borrmann, Karoline Diehl, Subir K. Mitra, and Miklós Szakáll
Atmos. Chem. Phys., 25, 11813–11828, https://doi.org/10.5194/acp-25-11813-2025, https://doi.org/10.5194/acp-25-11813-2025, 2025
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We investigated the retention of chemical species and their binary mixtures during freezing of raindrops via acoustic levitation. Our results reveal high retention, with nearly all substances being fully retained during freezing. This could be attributed to a faster freezing time compared to a slower mass expulsion time, along with ice shell formation during freezing. This result helps improve our understanding of the interaction between ice microphysical processes and chemistry in deep convective clouds.
Herman G. J. Smit, Torben Galle, Romain Blot, Florian Obersteiner, Philippe Nédélec, Andreas Zahn, Jean-Marc Cousin, Ulrich Bundke, Andreas Petzold, Valerie Thouret, and Hannah Clark
Atmos. Meas. Tech., 18, 4985–5001, https://doi.org/10.5194/amt-18-4985-2025, https://doi.org/10.5194/amt-18-4985-2025, 2025
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The two ozone instruments of IAGOS (In-service Aircraft for a Global Observation System) have been compared with the Ozone PhotoMeter (OPM) of the World Calibration Center of Ozone Sondes (WCCOS) in an atmospheric simulation chamber under realistic flight conditions of pressure, temperature, and ozone concentrations. The two IAGOS-instruments showed good agreement with the OPM within 5–6 %. The observed differences are small but systematic and reproducible during the intercomparison.
Johannes C. Laube, Tanja J. Schuck, Sophie Baartman, Huilin Chen, Markus Geldenhuys, Steven van Heuven, Timo Keber, Maria Elena Popa, Elinor Tuffnell, Florian Voet, Bärbel Vogel, Thomas Wagenhäuser, Alessandro Zanchetta, and Andreas Engel
Atmos. Meas. Tech., 18, 4087–4102, https://doi.org/10.5194/amt-18-4087-2025, https://doi.org/10.5194/amt-18-4087-2025, 2025
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A large balloon was launched in summer 2021 in the Arctic to carry instruments for trace gas measurements up to 32 km, above the reach of aircraft. The main aims were to evaluate different techniques and atmospheric processes. We focus on halogenated greenhouse gases and ozone-depleting substances. For this, air was collected with the AirCore technique and a cryogenic air sampler and measured after the flight. A companion paper reports observations of major greenhouse gases.
Rodrigo J. Seguel, Charlie Opazo, Yann Cohen, Owen R. Cooper, Laura Gallardo, Björn-Martin Sinnhuber, Florian Obersteiner, Andreas Zahn, Peter Hoor, Susanne Rohs, and Andreas Marsing
Atmos. Chem. Phys., 25, 8553–8573, https://doi.org/10.5194/acp-25-8553-2025, https://doi.org/10.5194/acp-25-8553-2025, 2025
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We explored ozone differences between the Northern Hemisphere and Southern Hemispheres in the upper troposphere–lower stratosphere. We found lower ozone (with stratospheric origin) in the Southern Hemisphere, especially during years of severe ozone depletion. Sudden stratospheric warming events increased the ozone in each hemisphere, highlighting the relationship between stratospheric processes and ozone in the upper troposphere, where ozone is an important greenhouse gas.
Markus Jesswein, Valentin Lauther, Nicolas Emig, Peter Hoor, Timo Keber, Hans-Christoph Lachnitt, Linda Ort, Tanja Schuck, Johannes Strobel, Ronja Van Luijt, C. Michael Volk, Franziska Weyland, and Andreas Engel
Atmos. Chem. Phys., 25, 8107–8126, https://doi.org/10.5194/acp-25-8107-2025, https://doi.org/10.5194/acp-25-8107-2025, 2025
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The study investigates transport within the Asian Summer Monsoon, focusing on how CH2Cl2 reaches the subarctic tropopause region. Using data from the PHILEAS campaign in 2023, events with increased mixing ratios were detected. Their origin, the transport paths to the tropopause region, and the potential entry into the stratosphere were analyzed. The East Asian Summer Monsoon was identified as the main transport pathway, with only a small contribution to the stratosphere in the following days.
Corinna Kloss, Gwenaël Berthet, Pasquale Sellitto, Irene Bartolome Garcia, Emmanuel Briaud, Rubel Chandra Das, Stéphane Chevrier, Nicolas Dumelié, Lilian Joly, Thomas Lecas, Pauline Marbach, Felix Ploeger, Jean-Baptiste Renard, Jean-Paul Vernier, Frank G. Wienhold, and Michaela I. Hegglin
EGUsphere, https://doi.org/10.5194/egusphere-2025-2091, https://doi.org/10.5194/egusphere-2025-2091, 2025
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In October 2022, we detected volcanic particles in the stratosphere over France, linked to the January 2022 Hunga eruption in the South Pacific. Found between 17 and 23 km altitude, they were traced back to the tropics using trajectory simulations and satellite data. Their optical properties matched those in the Southern Hemisphere. The particles spread across the Northern Hemisphere, reflecting sunlight and slightly cooling the surface—a small but non-negligible effect.
Yann Cohen, Didier Hauglustaine, Nicolas Bellouin, Marianne Tronstad Lund, Sigrun Matthes, Agnieszka Skowron, Robin Thor, Ulrich Bundke, Andreas Petzold, Susanne Rohs, Valérie Thouret, Andreas Zahn, and Helmut Ziereis
Atmos. Chem. Phys., 25, 5793–5836, https://doi.org/10.5194/acp-25-5793-2025, https://doi.org/10.5194/acp-25-5793-2025, 2025
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The chemical composition of the atmosphere near the tropopause is a key parameter for evaluating the climate impact of subsonic aviation pollutants. This study uses in situ data collected aboard passenger aircraft to assess the ability of four chemistry–climate models to reproduce (bi-)decadal climatologies of ozone, carbon monoxide, water vapour, and reactive nitrogen in this region. The models reproduce the very distinct ozone seasonality in the upper troposphere and in the lower stratosphere well.
Patrick Konjari, Christian Rolf, Michaela I. Hegglin, Susanne Rohs, Yun Li, Andreas Zahn, Harald Bönisch, Philippe Nedelec, Martina Krämer, and Andreas Petzold
Atmos. Chem. Phys., 25, 4269–4289, https://doi.org/10.5194/acp-25-4269-2025, https://doi.org/10.5194/acp-25-4269-2025, 2025
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This study introduces a new method to derive adjusted water vapor (H2O) climatologies for the upper tropopshere and lower statosphere (UT/LS) using data from 60 000 flights under the IAGOS program. Biases in the IAGOS water vapour dataset are adjusted, based on the more accurate IAGOS-CARIBIC data. The resulting highly resolved H2O climatologies will contribute to a better understanding of the H2O variability in the UT/LS and its connection to various transport and mixing processes.
Laura N. Saunders, Kaley A. Walker, Gabriele P. Stiller, Thomas von Clarmann, Florian Haenel, Hella Garny, Harald Bönisch, Chris D. Boone, Ariana E. Castillo, Andreas Engel, Johannes C. Laube, Marianna Linz, Felix Ploeger, David A. Plummer, Eric A. Ray, and Patrick E. Sheese
Atmos. Chem. Phys., 25, 4185–4209, https://doi.org/10.5194/acp-25-4185-2025, https://doi.org/10.5194/acp-25-4185-2025, 2025
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We present a 17-year stratospheric age-of-air dataset derived from ACE-FTS satellite measurements of sulfur hexafluoride. This is the longest continuous, global, and vertically resolved age of air time series available to date. In this paper, we show that this dataset agrees well with age-of-air datasets based on measurements from other instruments. We also present trends in the midlatitude lower stratosphere that indicate changes in the global circulation that are predicted by climate models.
Shubhajyoti Roy, Satheesh P. R. Chandran, Suvarna Fadnavis, Vijay Sagar, Michaela I. Hegglin, and Rolf Müller
EGUsphere, https://doi.org/10.5194/egusphere-2025-1098, https://doi.org/10.5194/egusphere-2025-1098, 2025
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We show stratospheric ozone intrusions associated with sudden stratospheric warming events enhance ozone in the lower troposphere over the South Asia. The ozone enhancement increases ozone radiative forcing by 0.04±0.03 W.m-2 over South Asia. This increase in ozone radiative forcing potentially exacerbates regional climate warming.
André Ehrlich, Susanne Crewell, Andreas Herber, Marcus Klingebiel, Christof Lüpkes, Mario Mech, Sebastian Becker, Stephan Borrmann, Heiko Bozem, Matthias Buschmann, Hans-Christian Clemen, Elena De La Torre Castro, Henning Dorff, Regis Dupuy, Oliver Eppers, Florian Ewald, Geet George, Andreas Giez, Sarah Grawe, Christophe Gourbeyre, Jörg Hartmann, Evelyn Jäkel, Philipp Joppe, Olivier Jourdan, Zsófia Jurányi, Benjamin Kirbus, Johannes Lucke, Anna E. Luebke, Maximilian Maahn, Nina Maherndl, Christian Mallaun, Johanna Mayer, Stephan Mertes, Guillaume Mioche, Manuel Moser, Hanno Müller, Veronika Pörtge, Nils Risse, Greg Roberts, Sophie Rosenburg, Johannes Röttenbacher, Michael Schäfer, Jonas Schaefer, Andreas Schäfler, Imke Schirmacher, Johannes Schneider, Sabrina Schnitt, Frank Stratmann, Christian Tatzelt, Christiane Voigt, Andreas Walbröl, Anna Weber, Bruno Wetzel, Martin Wirth, and Manfred Wendisch
Earth Syst. Sci. Data, 17, 1295–1328, https://doi.org/10.5194/essd-17-1295-2025, https://doi.org/10.5194/essd-17-1295-2025, 2025
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This paper provides an overview of the HALO–(AC)3 aircraft campaign data sets, the campaign-specific instrument operation, data processing, and data quality. The data set comprises in situ and remote sensing observations from three research aircraft: HALO, Polar 5, and Polar 6. All data are published in the PANGAEA database by instrument-separated data subsets. It is highlighted how the scientific analysis of the HALO–(AC)3 data benefits from the coordinated operation of three aircraft.
Florian Voet, Felix Ploeger, Johannes Laube, Peter Preusse, Paul Konopka, Jens-Uwe Grooß, Jörn Ungermann, Björn-Martin Sinnhuber, Michael Höpfner, Bernd Funke, Gerald Wetzel, Sören Johansson, Gabriele Stiller, Eric Ray, and Michaela I. Hegglin
Atmos. Chem. Phys., 25, 3541–3565, https://doi.org/10.5194/acp-25-3541-2025, https://doi.org/10.5194/acp-25-3541-2025, 2025
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This study refines estimates of the stratospheric “age of air”, a measure of how long air circulates in the stratosphere. By analyzing correlations between trace gases measurable by satellites, the research introduces a method that reduces uncertainties and detects small-scale atmospheric features. This improved understanding of stratospheric circulation is crucial for better climate models and predictions, enhancing our ability to assess the impacts of climate change on the atmosphere.
Prashant Chavan, Suvarna Fadnavis, Anton Laakso, Jean-Paul Vernier, Simone Tilmes, and Rolf Müller
EGUsphere, https://doi.org/10.5194/egusphere-2024-3825, https://doi.org/10.5194/egusphere-2024-3825, 2025
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Our simulations with volcanoes, when compared without volcanoes, show that volcanic aerosol precursors enter the tropical stratosphere, propagating upward and enhancing sulphate aerosol and heating. This stratospheric heating caused by the volcanoes reduces the amplitude of the QBO and disrupts its phases. Since QBO also modulates tropical convection and weather, we suggest including volcanic emissions and the QBO in the weather prediction model for a better forecast.
Kimberlee Dubé, Susann Tegtmeier, Felix Ploeger, and Kaley A. Walker
Atmos. Chem. Phys., 25, 1433–1447, https://doi.org/10.5194/acp-25-1433-2025, https://doi.org/10.5194/acp-25-1433-2025, 2025
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The transport rate of air in the stratosphere has changed in response to human emissions of greenhouse gases and ozone-depleting substances. This transport rate can be approximated using measurements of long-lived trace gases. We use observations and model results to derive anomalies and trends in the mean rate of stratospheric air transport. We find that air in the Northern Hemisphere aged by up to 0.3 years per decade relative to air in the Southern Hemisphere over 2004–2017.
Franziska Weyland, Peter Hoor, Daniel Kunkel, Thomas Birner, Felix Plöger, and Katharina Turhal
Atmos. Chem. Phys., 25, 1227–1252, https://doi.org/10.5194/acp-25-1227-2025, https://doi.org/10.5194/acp-25-1227-2025, 2025
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The lowermost stratosphere (LMS) plays an important role in the Earth's climate, containing strong gradients of ozone and water vapor. Our results indicate that the thermodynamic structure of the LMS was changing between 1979–2019 in response to anthropogenic climate change and the recovery of stratospheric ozone, also indicating large-scale circulation changes. We find that both the upper and the lower LMS boundaries show an (upward) trend, which has implications for the LMS mass.
Xiaolu Yan, Paul Konopka, Felix Ploeger, and Aurélien Podglajen
Atmos. Chem. Phys., 25, 1289–1305, https://doi.org/10.5194/acp-25-1289-2025, https://doi.org/10.5194/acp-25-1289-2025, 2025
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Our study finds that the air mass fractions (AMFs) from the Asian boundary layer (ABL) to the polar regions are about 1.5 times larger than those from the same latitude band in the Southern Hemisphere. The transport of AMFs from the ABL to the polar vortex primarily occurs above 20 km and over timescales exceeding 2 years. Our analysis reveals a strong correlation between the polar pollutants and the AMFs from the ABL. About 20 % of SF6 in the polar stratosphere originates from the ABL.
Christine Borchers, Jackson Seymore, Martanda Gautam, Konstantin Dörholt, Yannik Müller, Andreas Arndt, Laura Gömmer, Florian Ungeheuer, Miklós Szakáll, Stephan Borrmann, Alexander Theis, Alexander L. Vogel, and Thorsten Hoffmann
Atmos. Chem. Phys., 24, 13961–13974, https://doi.org/10.5194/acp-24-13961-2024, https://doi.org/10.5194/acp-24-13961-2024, 2024
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Riming, a crucial process in cloud dynamics, influences the vertical distribution of compounds in the atmosphere. Experiments in Mainz's wind tunnel investigated retention coefficients of organic compounds under varying conditions. Findings suggest a correlation between the Henry's law constant and retention, applicable even to complex organic molecules.
Katharina Turhal, Felix Plöger, Jan Clemens, Thomas Birner, Franziska Weyland, Paul Konopka, and Peter Hoor
Atmos. Chem. Phys., 24, 13653–13679, https://doi.org/10.5194/acp-24-13653-2024, https://doi.org/10.5194/acp-24-13653-2024, 2024
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The tropopause separates the troposphere, where many greenhouse gases originate, from the stratosphere. This study examines a tropopause defined by potential vorticity – an analogue for angular momentum that changes sharply in the subtropics, creating a transport barrier. Between 1980 and 2017, this tropopause shifted poleward at lower altitudes and equatorward above, suggesting height-dependent changes in atmospheric circulation that may affect greenhouse gas distribution and global warming.
Markus Kilian, Volker Grewe, Patrick Jöckel, Astrid Kerkweg, Mariano Mertens, Andreas Zahn, and Helmut Ziereis
Atmos. Chem. Phys., 24, 13503–13523, https://doi.org/10.5194/acp-24-13503-2024, https://doi.org/10.5194/acp-24-13503-2024, 2024
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Anthropogenic emissions are a major source of precursors of tropospheric ozone. As ozone formation is highly non-linear, we apply a global–regional chemistry–climate model with a source attribution method (tagging) to quantify the contribution of anthropogenic emissions to ozone. Our analysis shows that the contribution of European anthropogenic emissions largely increases during large ozone periods, indicating that emissions from these sectors drive ozone values.
Yiran Zhang-Liu, Rolf Müller, Jens-Uwe Grooß, Sabine Robrecht, Bärbel Vogel, Abdul Mannan Zafar, and Ralph Lehmann
Atmos. Chem. Phys., 24, 12557–12574, https://doi.org/10.5194/acp-24-12557-2024, https://doi.org/10.5194/acp-24-12557-2024, 2024
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HCl null cycles in Antarctica are important for maintaining high values of ozone-destroying chlorine in Antarctic spring. These HCl null cycles are not affected by (1) using the most recent recommendations of chemical kinetics (compared to older recommendations), (2) accounting for dehydration in the Antarctic winter vortex, and (3) considering the observed (but unexplained) depletion of HCl in mid-winter in the Antarctic vortex throughout Antarctic winter.
Julia Pikmann, Frank Drewnick, Friederike Fachinger, and Stephan Borrmann
Atmos. Chem. Phys., 24, 12295–12321, https://doi.org/10.5194/acp-24-12295-2024, https://doi.org/10.5194/acp-24-12295-2024, 2024
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Cooking activities can contribute substantially to indoor and ambient aerosol. We performed a comprehensive study with laboratory measurements cooking 19 different dishes and ambient measurements at two Christmas markets measuring various particle properties and trace gases of emissions in real time. Similar emission characteristics were observed for dishes with the same preparation method, mainly due to similar cooking temperature and use of oil, with barbecuing as an especially strong source.
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.
Randall Chiu, Florian Obersteiner, Alessandro Franchin, Teresa Campos, Adriana Bailey, Christopher Webster, Andreas Zahn, and Rainer Volkamer
Atmos. Meas. Tech., 17, 5731–5746, https://doi.org/10.5194/amt-17-5731-2024, https://doi.org/10.5194/amt-17-5731-2024, 2024
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The ozone sink into oceans and marine clouds is seldom studied and highly uncertain. Calculations suggest O3 destruction at aqueous surfaces (ocean, droplets) may be strongly accelerated, but field evidence is missing. Here we compare three fast airborne O3 instruments to measure eddy covariance fluxes of O3 over the remote ocean, in clear and cloudy air. We find O3 fluxes below clouds are consistently directed into clouds, while O3 fluxes into oceans are much smaller and spatially variable.
Manfred Wendisch, Susanne Crewell, André Ehrlich, Andreas Herber, Benjamin Kirbus, Christof Lüpkes, Mario Mech, Steven J. Abel, Elisa F. Akansu, Felix Ament, Clémantyne Aubry, Sebastian Becker, Stephan Borrmann, Heiko Bozem, Marlen Brückner, Hans-Christian Clemen, Sandro Dahlke, Georgios Dekoutsidis, Julien Delanoë, Elena De La Torre Castro, Henning Dorff, Regis Dupuy, Oliver Eppers, Florian Ewald, Geet George, Irina V. Gorodetskaya, Sarah Grawe, Silke Groß, Jörg Hartmann, Silvia Henning, Lutz Hirsch, Evelyn Jäkel, Philipp Joppe, Olivier Jourdan, Zsofia Jurányi, Michail Karalis, Mona Kellermann, Marcus Klingebiel, Michael Lonardi, Johannes Lucke, Anna E. Luebke, Maximilian Maahn, Nina Maherndl, Marion Maturilli, Bernhard Mayer, Johanna Mayer, Stephan Mertes, Janosch Michaelis, Michel Michalkov, Guillaume Mioche, Manuel Moser, Hanno Müller, Roel Neggers, Davide Ori, Daria Paul, Fiona M. Paulus, Christian Pilz, Felix Pithan, Mira Pöhlker, Veronika Pörtge, Maximilian Ringel, Nils Risse, Gregory C. Roberts, Sophie Rosenburg, Johannes Röttenbacher, Janna Rückert, Michael Schäfer, Jonas Schaefer, Vera Schemann, Imke Schirmacher, Jörg Schmidt, Sebastian Schmidt, Johannes Schneider, Sabrina Schnitt, Anja Schwarz, Holger Siebert, Harald Sodemann, Tim Sperzel, Gunnar Spreen, Bjorn Stevens, Frank Stratmann, Gunilla Svensson, Christian Tatzelt, Thomas Tuch, Timo Vihma, Christiane Voigt, Lea Volkmer, Andreas Walbröl, Anna Weber, Birgit Wehner, Bruno Wetzel, Martin Wirth, and Tobias Zinner
Atmos. Chem. Phys., 24, 8865–8892, https://doi.org/10.5194/acp-24-8865-2024, https://doi.org/10.5194/acp-24-8865-2024, 2024
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The Arctic is warming faster than the rest of the globe. Warm-air intrusions (WAIs) into the Arctic may play an important role in explaining this phenomenon. Cold-air outbreaks (CAOs) out of the Arctic may link the Arctic climate changes to mid-latitude weather. In our article, we describe how to observe air mass transformations during CAOs and WAIs using three research aircraft instrumented with state-of-the-art remote-sensing and in situ measurement devices.
Luis F. Millán, Peter Hoor, Michaela I. Hegglin, Gloria L. Manney, Harald Boenisch, Paul Jeffery, Daniel Kunkel, Irina Petropavlovskikh, Hao Ye, Thierry Leblanc, and Kaley Walker
Atmos. Chem. Phys., 24, 7927–7959, https://doi.org/10.5194/acp-24-7927-2024, https://doi.org/10.5194/acp-24-7927-2024, 2024
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In the Observed Composition Trends And Variability in the UTLS (OCTAV-UTLS) Stratosphere-troposphere Processes And their Role in Climate (SPARC) activity, we have mapped multiplatform ozone datasets into coordinate systems to systematically evaluate the influence of these coordinates on binned climatological variability. This effort unifies the work of studies that focused on individual coordinate system variability. Our goal was to create the most comprehensive assessment of this topic.
Niklas Karbach, Lisa Höhler, Peter Hoor, Heiko Bozem, Nicole Bobrowski, and Thorsten Hoffmann
Atmos. Meas. Tech., 17, 4081–4086, https://doi.org/10.5194/amt-17-4081-2024, https://doi.org/10.5194/amt-17-4081-2024, 2024
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The system presented here can accurately generate and reproduce a stable flow of gas mixtures of known concentrations over several days using ambient air as a dilution medium. In combination with the small size and low weight of the system, this enables the calibration of hydrogen sensors in the field, reducing the influence of matrix effects on the accuracy of the sensor. The system is inexpensive to assemble and easy to maintain, which is the key to reliable measurement results.
Philipp Joppe, Johannes Schneider, Katharina Kaiser, Horst Fischer, Peter Hoor, Daniel Kunkel, Hans-Christoph Lachnitt, Andreas Marsing, Lenard Röder, Hans Schlager, Laura Tomsche, Christiane Voigt, Andreas Zahn, and Stephan Borrmann
Atmos. Chem. Phys., 24, 7499–7522, https://doi.org/10.5194/acp-24-7499-2024, https://doi.org/10.5194/acp-24-7499-2024, 2024
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From aircraft measurements in the upper troposphere/lower stratosphere, we find a correlation between the ozone and particulate sulfate in the lower stratosphere. The correlation exhibits some variability over the measurement period exceeding the background sulfate-to-ozone correlation. From our analysis, we conclude that gas-to-particle conversion of volcanic sulfur dioxide leads to observed enhanced sulfate aerosol mixing ratios.
Sandra Graßl, Christoph Ritter, Ines Tritscher, and Bärbel Vogel
Atmos. Chem. Phys., 24, 7535–7557, https://doi.org/10.5194/acp-24-7535-2024, https://doi.org/10.5194/acp-24-7535-2024, 2024
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Arctic lidar data for 1 year are compared with global modeling of aerosol tracers in the stratosphere. A trend in the aerosol backscatter can be found. These observations are further compared with a model study to investigate the aerosol origin of the observed arctic aerosol. We found a correlation with increased backscatter signal during summer and early autumn and pathways from the Southeast Asian monsoon region and remains of the Asian tropopause aerosol layer in the Arctic.
Jayanarayanan Kuttippurath, Gopalakrishna Pillai Gopikrishnan, Rolf Müller, Sophie Godin-Beekmann, and Jerome Brioude
Atmos. Chem. Phys., 24, 6743–6756, https://doi.org/10.5194/acp-24-6743-2024, https://doi.org/10.5194/acp-24-6743-2024, 2024
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The current understanding and observational evidence do not provide any support for the possibility of an ozone hole occurring outside Antarctica today with respect to the present-day stratospheric halogen levels.
Hengheng Zhang, Christian Rolf, Ralf Tillmann, Christian Wesolek, Frank Gunther Wienhold, Thomas Leisner, and Harald Saathoff
Aerosol Research, 2, 135–151, https://doi.org/10.5194/ar-2-135-2024, https://doi.org/10.5194/ar-2-135-2024, 2024
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Our study employs advanced tools, including scanning lidar, balloons, and UAVs, to explore aerosol particles in the atmosphere. The scanning lidar offers distinctive near-ground-level insights, enriching our comprehension of aerosol distribution from ground level to the free troposphere. This research provides valuable data for comparing remote sensing and in situ aerosol measurements, advancing our understanding of aerosol impacts on radiative transfer, clouds, and air quality.
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.
Cristina Peña-Ortiz, Nuria Pilar Plaza, David Gallego, and Felix Ploeger
Atmos. Chem. Phys., 24, 5457–5478, https://doi.org/10.5194/acp-24-5457-2024, https://doi.org/10.5194/acp-24-5457-2024, 2024
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Although water vapour (H2O) in the lower stratosphere is only a few molecules among 1 million air molecules, atmospheric radiative forcing and surface temperature are sensitive to changes in its concentration. Monsoon regions play a key role in H2O transport and its concentration in the lower stratosphere. We show how the quasi-biennial oscillation (QBO) has a major impact on H2O over the Asian monsoon during August through changes in temperature caused by QBO modulation of tropical clouds.
Martin Ebert, Ralf Weigel, Stephan Weinbruch, Lisa Schneider, Konrad Kandler, Stefan Lauterbach, Franziska Köllner, Felix Plöger, Gebhard Günther, Bärbel Vogel, and Stephan Borrmann
Atmos. Chem. Phys., 24, 4771–4788, https://doi.org/10.5194/acp-24-4771-2024, https://doi.org/10.5194/acp-24-4771-2024, 2024
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Particles were collected during the flight campaign StratoClim 2017 within the Asian tropopause aerosol layer (ATAL). Refractory particles from seven different flights were characterized by scanning and transmission electron microscopy (SEM, TEM). The most abundant refractory particles are silicates and non-volatile organics. The most important sources are combustion processes at the ground and the agitation of soil material. During one flight, small cinnabar particles (HgS) were also detected.
Adrien Deroubaix, Marco Vountas, Benjamin Gaubert, Maria Dolores Andrés Hernández, Stephan Borrmann, Guy Brasseur, Bruna Holanda, Yugo Kanaya, Katharina Kaiser, Flora Kluge, Ovid Oktavian Krüger, Inga Labuhn, Michael Lichtenstern, Klaus Pfeilsticker, Mira Pöhlker, Hans Schlager, Johannes Schneider, Guillaume Siour, Basudev Swain, Paolo Tuccella, Kameswara S. Vinjamuri, Mihalis Vrekoussis, Benjamin Weyland, and John P. Burrows
EGUsphere, https://doi.org/10.5194/egusphere-2024-516, https://doi.org/10.5194/egusphere-2024-516, 2024
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This study assesses atmospheric composition using air quality models during aircraft campaigns in Europe and Asia, focusing on carbonaceous aerosols and trace gases. While carbon monoxide is well modeled, other pollutants have moderate to weak agreement with observations. Wind speed modeling is reliable for identifying pollution plumes, where models tend to overestimate concentrations. This highlights challenges in accurately modeling aerosol and trace gas composition, particularly in cities.
Adrien Deroubaix, Marco Vountas, Benjamin Gaubert, Maria Dolores Andrés Hernández, Stephan Borrmann, Guy Brasseur, Bruna Holanda, Yugo Kanaya, Katharina Kaiser, Flora Kluge, Ovid Oktavian Krüger, Inga Labuhn, Michael Lichtenstern, Klaus Pfeilsticker, Mira Pöhlker, Hans Schlager, Johannes Schneider, Guillaume Siour, Basudev Swain, Paolo Tuccella, Kameswara S. Vinjamuri, Mihalis Vrekoussis, Benjamin Weyland, and John P. Burrows
EGUsphere, https://doi.org/10.5194/egusphere-2024-521, https://doi.org/10.5194/egusphere-2024-521, 2024
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This study explores the proportional relationships between carbonaceous aerosols (black and organic carbon) and trace gases using airborne measurements from two campaigns in Europe and East Asia. Differences between regions were found, but air quality models struggled to reproduce them accurately. We show that these proportional relationships can help to constrain models and can be used to infer aerosol concentrations from satellite observations of trace gases, especially in urban areas.
Felix Ploeger, Thomas Birner, Edward Charlesworth, Paul Konopka, and Rolf Müller
Atmos. Chem. Phys., 24, 2033–2043, https://doi.org/10.5194/acp-24-2033-2024, https://doi.org/10.5194/acp-24-2033-2024, 2024
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We present a novel mechanism of how regional anomalies in water vapour concentrations in the upper troposphere and lower stratosphere impact regional atmospheric circulation systems. These impacts include a displaced upper-level Asian monsoon circulation and strengthened prevailing westerlies in the Pacific region. Current climate models have biases in simulating these regional water vapour anomalies and circulation impacts, but the biases can be avoided by improving the model transport.
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.
Tanja J. Schuck, Johannes Degen, Eric Hintsa, Peter Hoor, Markus Jesswein, Timo Keber, Daniel Kunkel, Fred Moore, Florian Obersteiner, Matt Rigby, Thomas Wagenhäuser, Luke M. Western, Andreas Zahn, and Andreas Engel
Atmos. Chem. Phys., 24, 689–705, https://doi.org/10.5194/acp-24-689-2024, https://doi.org/10.5194/acp-24-689-2024, 2024
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We study the interhemispheric gradient of sulfur hexafluoride (SF6), a strong long-lived greenhouse gas. Its emissions are stronger in the Northern Hemisphere; therefore, mixing ratios in the Southern Hemisphere lag behind. Comparing the observations to a box model, the model predicts air in the Southern Hemisphere to be older. For a better agreement, the emissions used as model input need to be increased (and their spatial pattern changed), and we need to modify north–south transport.
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.
Rolf Müller, Ulrich Pöschl, Thomas Koop, Thomas Peter, and Ken Carslaw
Atmos. Chem. Phys., 23, 15445–15453, https://doi.org/10.5194/acp-23-15445-2023, https://doi.org/10.5194/acp-23-15445-2023, 2023
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Paul J. Crutzen was a pioneer in atmospheric sciences and a kind-hearted, humorous person with empathy for the private lives of his colleagues and students. He made fundamental scientific contributions to a wide range of scientific topics in all parts of the atmosphere. Paul was among the founders of the journal Atmospheric Chemistry and Physics. His work will continue to be a guide for generations of scientists and environmental policymakers to come.
Yann Cohen, Didier Hauglustaine, Bastien Sauvage, Susanne Rohs, Patrick Konjari, Ulrich Bundke, Andreas Petzold, Valérie Thouret, Andreas Zahn, and Helmut Ziereis
Atmos. Chem. Phys., 23, 14973–15009, https://doi.org/10.5194/acp-23-14973-2023, https://doi.org/10.5194/acp-23-14973-2023, 2023
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The upper troposphere–lower stratosphere (UTLS) is a key region regarding the lower atmospheric composition. This study consists of a comprehensive evaluation of an up-to-date chemistry–climate model in this layer, using regular in situ measurements based on passenger aircraft. For this purpose, a specific software (Interpol-IAGOS) has been updated and made publicly available. The model reproduces the carbon monoxide peaks due to biomass burning over the continental tropics particularly well.
Thomas Trickl, Martin Adelwart, Dina Khordakova, Ludwig Ries, Christian Rolf, Michael Sprenger, Wolfgang Steinbrecht, and Hannes Vogelmann
Atmos. Meas. Tech., 16, 5145–5165, https://doi.org/10.5194/amt-16-5145-2023, https://doi.org/10.5194/amt-16-5145-2023, 2023
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Tropospheric ozone have been measured for more than a century. Highly quantitative ozone measurements have been made at monitoring stations. However, deficits have been reported for vertical sounding systems. Here, we report a thorough intercomparison effort between a differential-absorption lidar system and two types of balloon-borne ozone sondes, also using ozone sensors at nearby mountain sites as references. The sondes agree very well with the lidar after offset corrections.
Francesco Cairo, Martina Krämer, Armin Afchine, Guido Di Donfrancesco, Luca Di Liberto, Sergey Khaykin, Lorenza Lucaferri, Valentin Mitev, Max Port, Christian Rolf, Marcel Snels, Nicole Spelten, Ralf Weigel, and Stephan Borrmann
Atmos. Meas. Tech., 16, 4899–4925, https://doi.org/10.5194/amt-16-4899-2023, https://doi.org/10.5194/amt-16-4899-2023, 2023
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Cirrus clouds have been observed over the Himalayan region between 10 km and the tropopause at 17–18 km. Data from backscattersonde, hygrometers, and particle cloud spectrometers have been compared to assess their consistency. Empirical relationships between optical parameters accessible with remote sensing lidars and cloud microphysical parameters (such as ice water content, particle number and surface area density, and particle aspherical fraction) have been established.
Pierre Grzegorczyk, Sudha Yadav, Florian Zanger, Alexander Theis, Subir K. Mitra, Stephan Borrmann, and Miklós Szakáll
Atmos. Chem. Phys., 23, 13505–13521, https://doi.org/10.5194/acp-23-13505-2023, https://doi.org/10.5194/acp-23-13505-2023, 2023
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Secondary ice production generates high concentrations of ice crystals in clouds. These processes have been poorly understood. We conducted experiments at the wind tunnel laboratory of the Johannes Gutenberg University, Mainz, on graupel–graupel and graupel–snowflake collisions. From these experiments fragment number, size, cross-sectional area, and aspect ratio were determined.
Paul Konopka, Christian Rolf, Marc von Hobe, Sergey M. Khaykin, Benjamin Clouser, Elisabeth Moyer, Fabrizio Ravegnani, Francesco D'Amato, Silvia Viciani, Nicole Spelten, Armin Afchine, Martina Krämer, Fred Stroh, and Felix Ploeger
Atmos. Chem. Phys., 23, 12935–12947, https://doi.org/10.5194/acp-23-12935-2023, https://doi.org/10.5194/acp-23-12935-2023, 2023
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We studied water vapor in a critical region of the atmosphere, the Asian summer monsoon anticyclone, using rare in situ observations. Our study shows that extremely high water vapor values observed in the stratosphere within the Asian monsoon anticyclone still undergo significant freeze-drying and that water vapor concentrations set by the Lagrangian dry point are a better proxy for the stratospheric water vapor budget than rare observations of enhanced water mixing ratios.
Frederik Harzer, Hella Garny, Felix Ploeger, Harald Bönisch, Peter Hoor, and Thomas Birner
Atmos. Chem. Phys., 23, 10661–10675, https://doi.org/10.5194/acp-23-10661-2023, https://doi.org/10.5194/acp-23-10661-2023, 2023
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We study the statistical relation between year-by-year fluctuations in winter-mean ozone and the strength of the stratospheric polar vortex. In the latitude–pressure plane, regression analysis shows that anomalously weak polar vortex years are associated with three pronounced local ozone maxima over the polar cap relative to the winter climatology. These response maxima primarily reflect the non-trivial combination of different ozone transport processes with varying relative contributions.
Suvarna Fadnavis, Bernd Heinold, T. P. Sabin, Anne Kubin, Katty Huang, Alexandru Rap, and Rolf Müller
Atmos. Chem. Phys., 23, 10439–10449, https://doi.org/10.5194/acp-23-10439-2023, https://doi.org/10.5194/acp-23-10439-2023, 2023
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The influence of the COVID-19 lockdown on the Himalayas caused increases in snow cover and a decrease in runoff, ultimately leading to an enhanced snow water equivalent. Our findings highlight that, out of the two processes causing a retreat of Himalayan glaciers – (1) slow response to global climate change and (2) fast response to local air pollution – a policy action on the latter is more likely to be within the reach of possible policy action to help billions of people in southern Asia.
Marco Zanatta, Stephan Mertes, Olivier Jourdan, Regis Dupuy, Emma Järvinen, Martin Schnaiter, Oliver Eppers, Johannes Schneider, Zsófia Jurányi, and Andreas Herber
Atmos. Chem. Phys., 23, 7955–7973, https://doi.org/10.5194/acp-23-7955-2023, https://doi.org/10.5194/acp-23-7955-2023, 2023
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Black carbon (BC) particles influence the Arctic radiative balance. Vertical measurements of black carbon were conducted during the ACLOUD campaign in the European Arctic to study the interaction of BC with clouds. This study shows that clouds influence the vertical variability of BC properties across the inversion layer and that multiple activation and transformation mechanisms of BC may occur in the presence of low-level, persistent, mixed-phase clouds.
Midhun George, Maria Dolores Andrés Hernández, Vladyslav Nenakhov, Yangzhuoran Liu, John Philip Burrows, Birger Bohn, Eric Förster, Florian Obersteiner, Andreas Zahn, Theresa Harlaß, Helmut Ziereis, Hans Schlager, Benjamin Schreiner, Flora Kluge, Katja Bigge, and Klaus Pfeilsticker
Atmos. Chem. Phys., 23, 7799–7822, https://doi.org/10.5194/acp-23-7799-2023, https://doi.org/10.5194/acp-23-7799-2023, 2023
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The applicability of photostationary steady-state (PSS) assumptions to estimate the amount of the sum of peroxy radicals (RO2*) during the EMeRGe airborne observations from the known radical chemistry and onboard measurements of RO2* precursors, photolysis frequencies, and other trace gases such as NOx and O3 was investigated. The comparison of the calculated RO2* with the actual measurements provides an insight into the main processes controlling their concentration in the air masses measured.
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.
Manuel Moser, Christiane Voigt, Tina Jurkat-Witschas, Valerian Hahn, Guillaume Mioche, Olivier Jourdan, Régis Dupuy, Christophe Gourbeyre, Alfons Schwarzenboeck, Johannes Lucke, Yvonne Boose, Mario Mech, Stephan Borrmann, André Ehrlich, Andreas Herber, Christof Lüpkes, and Manfred Wendisch
Atmos. Chem. Phys., 23, 7257–7280, https://doi.org/10.5194/acp-23-7257-2023, https://doi.org/10.5194/acp-23-7257-2023, 2023
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This study provides a comprehensive microphysical and thermodynamic phase analysis of low-level clouds in the northern Fram Strait, above the sea ice and the open ocean, during spring and summer. Using airborne in situ cloud data, we show that the properties of Arctic low-level clouds vary significantly with seasonal meteorological situations and surface conditions. The observations presented in this study can help one to assess the role of clouds in the Arctic climate system.
Luis F. Millán, Gloria L. Manney, Harald Boenisch, Michaela I. Hegglin, Peter Hoor, Daniel Kunkel, Thierry Leblanc, Irina Petropavlovskikh, Kaley Walker, Krzysztof Wargan, and Andreas Zahn
Atmos. Meas. Tech., 16, 2957–2988, https://doi.org/10.5194/amt-16-2957-2023, https://doi.org/10.5194/amt-16-2957-2023, 2023
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The determination of atmospheric composition trends in the upper troposphere and lower stratosphere (UTLS) is still highly uncertain. We present the creation of dynamical diagnostics to map several ozone datasets (ozonesondes, lidars, aircraft, and satellite measurements) in geophysically based coordinate systems. The diagnostics can also be used to analyze other greenhouse gases relevant to surface climate and UTLS chemistry.
Claudio Belotti, Flavio Barbara, Marco Barucci, Giovanni Bianchini, Francesco D'Amato, Samuele Del Bianco, Gianluca Di Natale, Marco Gai, Alessio Montori, Filippo Pratesi, Markus Rettinger, Christian Rolf, Ralf Sussmann, Thomas Trickl, Silvia Viciani, Hannes Vogelmann, and Luca Palchetti
Atmos. Meas. Tech., 16, 2511–2529, https://doi.org/10.5194/amt-16-2511-2023, https://doi.org/10.5194/amt-16-2511-2023, 2023
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FIRMOS (Far-Infrared Radiation Mobile Observation System) is a spectroradiometer measuring in the far-infrared, developed to support the preparation of the FORUM (Far-infrared Outgoing Radiation Understanding and Monitoring) satellite mission. In this paper, we describe the instrument, its data products, and the results of the comparison with a suite of observations made from a high-altitude site during a field campaign, in winter 2018–2019.
Julia Pikmann, Lasse Moormann, Frank Drewnick, and Stephan Borrmann
Atmos. Meas. Tech., 16, 1323–1341, https://doi.org/10.5194/amt-16-1323-2023, https://doi.org/10.5194/amt-16-1323-2023, 2023
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Aerosols measured in complex environments are usually a mixture of emissions from different sources. To characterize sources individually, we developed a sampling system for particles and organic trace gases which is coupled to real-time data of physical and chemical aerosol properties, gas concentrations, and meteorological variables. Using suitable sampling conditions for individual aerosols which are compared with the real-time data the desired aerosols are sampled separately from each other.
Georgios Dekoutsidis, Silke Groß, Martin Wirth, Martina Krämer, and Christian Rolf
Atmos. Chem. Phys., 23, 3103–3117, https://doi.org/10.5194/acp-23-3103-2023, https://doi.org/10.5194/acp-23-3103-2023, 2023
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Cirrus clouds affect Earth's atmosphere, deeming our study important. Here we use water vapor measurements by lidar and study the relative humidity (RHi) within and around midlatitude cirrus clouds. We find high supersaturations in the cloud-free air and within the clouds, especially near the cloud top. We study two cloud types with different formation processes. Finally, we conclude that the shape of the distribution of RHi can be used as an indicator of different cloud evolutionary stages.
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.
Andreas Marsing, Ralf Meerkötter, Romy Heller, Stefan Kaufmann, Tina Jurkat-Witschas, Martina Krämer, Christian Rolf, and Christiane Voigt
Atmos. Chem. Phys., 23, 587–609, https://doi.org/10.5194/acp-23-587-2023, https://doi.org/10.5194/acp-23-587-2023, 2023
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We employ highly resolved aircraft measurements of profiles of the ice water content (IWC) in Arctic cirrus clouds in winter and spring, when solar irradiation is low. Using radiation transfer calculations, we assess the cloud radiative effect over different surfaces like snow or ocean. The variability in the IWC of the clouds affects their overall radiative effect and drives internal processes. This helps understand the role of cirrus in a rapidly changing Arctic environment.
Hans-Christoph Lachnitt, Peter Hoor, Daniel Kunkel, Martina Bramberger, Andreas Dörnbrack, Stefan Müller, Philipp Reutter, Andreas Giez, Thorsten Kaluza, and Markus Rapp
Atmos. Chem. Phys., 23, 355–373, https://doi.org/10.5194/acp-23-355-2023, https://doi.org/10.5194/acp-23-355-2023, 2023
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We present an analysis of high-resolution airborne measurements during a flight of the DEEPWAVE 2014 campaign in New Zealand. The focus of this flight was to study the effects of enhanced mountain wave activity over the Southern Alps. We discuss changes in the upstream and downstream distributions of N2O and CO and show that these changes are related to turbulence-induced trace gas fluxes which have persistent effects on the trace gas composition in the lower stratosphere.
Laura Tomsche, Andreas Marsing, Tina Jurkat-Witschas, Johannes Lucke, Stefan Kaufmann, Katharina Kaiser, Johannes Schneider, Monika Scheibe, Hans Schlager, Lenard Röder, Horst Fischer, Florian Obersteiner, Andreas Zahn, Martin Zöger, Jos Lelieveld, and Christiane Voigt
Atmos. Chem. Phys., 22, 15135–15151, https://doi.org/10.5194/acp-22-15135-2022, https://doi.org/10.5194/acp-22-15135-2022, 2022
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The detection of sulfur compounds in the upper troposphere (UT) and lower stratosphere (LS) is a challenge. In-flight measurements of SO2 and sulfate aerosol were performed during the BLUESKY mission in spring 2020 under exceptional atmospheric conditions. Reduced sinks in the dry UTLS and lower but still significant air traffic influenced the enhanced SO2 in the UT, and aged volcanic plumes enhanced the LS sulfate aerosol impacting the atmospheric radiation budget and global climate.
Bernard Legras, Clair Duchamp, Pasquale Sellitto, Aurélien Podglajen, Elisa Carboni, Richard Siddans, Jens-Uwe Grooß, Sergey Khaykin, and Felix Ploeger
Atmos. Chem. Phys., 22, 14957–14970, https://doi.org/10.5194/acp-22-14957-2022, https://doi.org/10.5194/acp-22-14957-2022, 2022
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The long-duration atmospheric impact of the Tonga eruption in January 2022 is a plume of water and sulfate aerosols in the stratosphere that persisted for more than 6 months. We study this evolution using several satellite instruments and analyse the unusual behaviour of this plume as sulfates and water first moved down rapidly and then separated into two layers. We also report the self-organization in compact and long-lived patches.
Mohamadou A. Diallo, Felix Ploeger, Michaela I. Hegglin, Manfred Ern, Jens-Uwe Grooß, Sergey Khaykin, and Martin Riese
Atmos. Chem. Phys., 22, 14303–14321, https://doi.org/10.5194/acp-22-14303-2022, https://doi.org/10.5194/acp-22-14303-2022, 2022
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The quasi-biennial oacillation disruption events in both 2016 and 2020 decreased lower-stratospheric water vapour and ozone. Differences in the strength and depth of the anomalous lower-stratospheric circulation and ozone are due to differences in tropical upwelling and cold-point temperature induced by lower-stratospheric planetary and gravity wave breaking. The differences in water vapour are due to higher cold-point temperature in 2020 induced by Australian wildfire.
Oliver Appel, Franziska Köllner, Antonis Dragoneas, Andreas Hünig, Sergej Molleker, Hans Schlager, Christoph Mahnke, Ralf Weigel, Max Port, Christiane Schulz, Frank Drewnick, Bärbel Vogel, Fred Stroh, and Stephan Borrmann
Atmos. Chem. Phys., 22, 13607–13630, https://doi.org/10.5194/acp-22-13607-2022, https://doi.org/10.5194/acp-22-13607-2022, 2022
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This paper clarifies the chemical composition of the Asian tropopause aerosol layer (ATAL) by means of airborne in situ aerosol mass spectrometry (AMS). Ammonium nitrate and organics are found to significantly contribute to the particle layer, while sulfate does not show a layered structure. An analysis of the single-particle mass spectra suggests that secondary particle formation and subsequent growth dominate the particle composition, rather than condensation on pre-existing primary particles.
Antonis Dragoneas, Sergej Molleker, Oliver Appel, Andreas Hünig, Thomas Böttger, Markus Hermann, Frank Drewnick, Johannes Schneider, Ralf Weigel, and Stephan Borrmann
Atmos. Meas. Tech., 15, 5719–5742, https://doi.org/10.5194/amt-15-5719-2022, https://doi.org/10.5194/amt-15-5719-2022, 2022
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The ERICA is a specially designed aerosol particle mass spectrometer for in situ, real-time chemical composition analysis of aerosols. It can operate completely autonomously, in the absence of an instrument operator. Its design has enabled its operation under harsh conditions, like those experienced in the upper troposphere and lower stratosphere, aboard unpressurized high-altitude research aircraft. The instrument has successfully participated in several aircraft operations around the world.
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.
Simon F. Reifenberg, Anna Martin, Matthias Kohl, Sara Bacer, Zaneta Hamryszczak, Ivan Tadic, Lenard Röder, Daniel J. Crowley, Horst Fischer, Katharina Kaiser, Johannes Schneider, Raphael Dörich, John N. Crowley, Laura Tomsche, Andreas Marsing, Christiane Voigt, Andreas Zahn, Christopher Pöhlker, Bruna A. Holanda, Ovid Krüger, Ulrich Pöschl, Mira Pöhlker, Patrick Jöckel, Marcel Dorf, Ulrich Schumann, Jonathan Williams, Birger Bohn, Joachim Curtius, Hardwig Harder, Hans Schlager, Jos Lelieveld, and Andrea Pozzer
Atmos. Chem. Phys., 22, 10901–10917, https://doi.org/10.5194/acp-22-10901-2022, https://doi.org/10.5194/acp-22-10901-2022, 2022
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In this work we use a combination of observational data from an aircraft campaign and model results to investigate the effect of the European lockdown due to COVID-19 in spring 2020. Using model results, we show that the largest relative changes to the atmospheric composition caused by the reduced emissions are located in the upper troposphere around aircraft cruise altitude, while the largest absolute changes are present at the surface.
Clare E. Singer, Benjamin W. Clouser, Sergey M. Khaykin, Martina Krämer, Francesco Cairo, Thomas Peter, Alexey Lykov, Christian Rolf, Nicole Spelten, Armin Afchine, Simone Brunamonti, and Elisabeth J. Moyer
Atmos. Meas. Tech., 15, 4767–4783, https://doi.org/10.5194/amt-15-4767-2022, https://doi.org/10.5194/amt-15-4767-2022, 2022
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In situ measurements of water vapor in the upper troposphere are necessary to study cloud formation and hydration of the stratosphere but challenging due to cold–dry conditions. We compare measurements from three water vapor instruments from the StratoClim campaign in 2017. In clear sky (clouds), point-by-point differences were <1.5±8 % (<1±8 %). This excellent agreement allows detection of fine-scale structures required to understand the impact of convection on stratospheric water vapor.
Liubov Poshyvailo-Strube, Rolf Müller, Stephan Fueglistaler, Michaela I. Hegglin, Johannes C. Laube, C. Michael Volk, and Felix Ploeger
Atmos. Chem. Phys., 22, 9895–9914, https://doi.org/10.5194/acp-22-9895-2022, https://doi.org/10.5194/acp-22-9895-2022, 2022
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Brewer–Dobson circulation (BDC) controls the composition of the stratosphere, which in turn affects radiation and climate. As the BDC cannot be measured directly, it is necessary to infer its strength and trends indirectly. In this study, we test in the
model worlddifferent methods for estimating the mean age of air trends based on a combination of stratospheric water vapour and methane data. We also provide simple practical advice of a more reliable estimation of the mean age of air trends.
Linda Smoydzin and Peter Hoor
Atmos. Chem. Phys., 22, 7193–7206, https://doi.org/10.5194/acp-22-7193-2022, https://doi.org/10.5194/acp-22-7193-2022, 2022
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Our study presents a detailed analysis of the spatial and temporal distribution of elevated CO level in the upper troposphere over the Pacific using 20 years of MOPITT data. We create a climatology of severe pollution episodes and use trajectory calculations to link each particular pollution event detected in MOPITT satellite data with a distinct source region. Additionally, we analyse uplift mechanisms such as WCB-related upward transport.
Suvarna Fadnavis, Prashant Chavan, Akash Joshi, Sunil M. Sonbawne, Asutosh Acharya, Panuganti C. S. Devara, Alexandru Rap, Felix Ploeger, and Rolf Müller
Atmos. Chem. Phys., 22, 7179–7191, https://doi.org/10.5194/acp-22-7179-2022, https://doi.org/10.5194/acp-22-7179-2022, 2022
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We show that large amounts of anthropogenic aerosols are transported from South Asia to the northern Indian Ocean. These aerosols are then lifted into the UTLS by the ascending branch of the Hadley circulation. They are further transported to the Southern Hemisphere and downward via westerly ducts over the tropical Atlantic and Pacific. These aerosols increase tropospheric heating, resulting in an increase in water vapor, which is then transported to the UTLS.
Andreas Hünig, Oliver Appel, Antonis Dragoneas, Sergej Molleker, Hans-Christian Clemen, Frank Helleis, Thomas Klimach, Franziska Köllner, Thomas Böttger, Frank Drewnick, Johannes Schneider, and Stephan Borrmann
Atmos. Meas. Tech., 15, 2889–2921, https://doi.org/10.5194/amt-15-2889-2022, https://doi.org/10.5194/amt-15-2889-2022, 2022
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We have serially combined the two well-established methods for in situ real-time measurement of fine particle chemical composition, the single-particle laser ablation method and the flash evaporation with electron impact ionization method, into a novel instrument. Here we present the design; instrument characteristics, as derived from laboratory and field measurements; and results from the first field deployment during the 2017 StratoClim aircraft campaign.
M. Dolores Andrés Hernández, Andreas Hilboll, Helmut Ziereis, Eric Förster, Ovid O. Krüger, Katharina Kaiser, Johannes Schneider, Francesca Barnaba, Mihalis Vrekoussis, Jörg Schmidt, Heidi Huntrieser, Anne-Marlene Blechschmidt, Midhun George, Vladyslav Nenakhov, Theresa Harlass, Bruna A. Holanda, Jennifer Wolf, Lisa Eirenschmalz, Marc Krebsbach, Mira L. Pöhlker, Anna B. Kalisz Hedegaard, Linlu Mei, Klaus Pfeilsticker, Yangzhuoran Liu, Ralf Koppmann, Hans Schlager, Birger Bohn, Ulrich Schumann, Andreas Richter, Benjamin Schreiner, Daniel Sauer, Robert Baumann, Mariano Mertens, Patrick Jöckel, Markus Kilian, Greta Stratmann, Christopher Pöhlker, Monica Campanelli, Marco Pandolfi, Michael Sicard, José L. Gómez-Amo, Manuel Pujadas, Katja Bigge, Flora Kluge, Anja Schwarz, Nikos Daskalakis, David Walter, Andreas Zahn, Ulrich Pöschl, Harald Bönisch, Stephan Borrmann, Ulrich Platt, and John P. Burrows
Atmos. Chem. Phys., 22, 5877–5924, https://doi.org/10.5194/acp-22-5877-2022, https://doi.org/10.5194/acp-22-5877-2022, 2022
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EMeRGe provides a unique set of in situ and remote sensing airborne measurements of trace gases and aerosol particles along selected flight routes in the lower troposphere over Europe. The interpretation uses also complementary collocated ground-based and satellite measurements. The collected data help to improve the current understanding of the complex spatial distribution of trace gases and aerosol particles resulting from mixing, transport, and transformation of pollution plumes over Europe.
Andreas Wieser, Andreas Güntner, Peter Dietrich, Jan Handwerker, Dina Khordakova, Uta Ködel, Martin Kohler, Hannes Mollenhauer, Bernhard Mühr, Erik Nixdorf, Marvin Reich, Christian Rolf, Martin Schrön, Claudia Schütze, and Ute Weber
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2022-131, https://doi.org/10.5194/hess-2022-131, 2022
Preprint withdrawn
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We present an event-triggered observation concept which covers the entire process chain from heavy precipitation to flooding at the catchment scale. It combines flexible and mobile observing systems out of the fields of meteorology, hydrology and geophysics with stationary networks to capture atmospheric transport processes, heterogeneous precipitation patterns, land surface and subsurface storage processes, and runoff dynamics.
Felix Ploeger and Hella Garny
Atmos. Chem. Phys., 22, 5559–5576, https://doi.org/10.5194/acp-22-5559-2022, https://doi.org/10.5194/acp-22-5559-2022, 2022
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We investigate hemispheric asymmetries in stratospheric circulation changes in the last 2 decades in model simulations and atmospheric observations. We find that observed trace gas changes can be explained by a structural circulation change related to a deepening circulation in the Northern Hemisphere relative to the Southern Hemisphere. As this asymmetric signal is small compared to internal variability observed circulation trends over the recent past are not in contradiction to climate models.
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.
Jan Clemens, Felix Ploeger, Paul Konopka, Raphael Portmann, Michael Sprenger, and Heini Wernli
Atmos. Chem. Phys., 22, 3841–3860, https://doi.org/10.5194/acp-22-3841-2022, https://doi.org/10.5194/acp-22-3841-2022, 2022
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Highly polluted air flows from the surface to higher levels of the atmosphere during the Asian summer monsoon. At high levels, the air is trapped within eddies. Here, we study how air masses can leave the eddy within its cutoff, how they distribute, and how their chemical composition changes. We found evidence for transport from the eddy to higher latitudes over the North Pacific and even Alaska. During transport, trace gas concentrations within cutoffs changed gradually, showing steady mixing.
Helmut Ziereis, Peter Hoor, Jens-Uwe Grooß, Andreas Zahn, Greta Stratmann, Paul Stock, Michael Lichtenstern, Jens Krause, Vera Bense, Armin Afchine, Christian Rolf, Wolfgang Woiwode, Marleen Braun, Jörn Ungermann, Andreas Marsing, Christiane Voigt, Andreas Engel, Björn-Martin Sinnhuber, and Hermann Oelhaf
Atmos. Chem. Phys., 22, 3631–3654, https://doi.org/10.5194/acp-22-3631-2022, https://doi.org/10.5194/acp-22-3631-2022, 2022
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Airborne observations were conducted in the lowermost Arctic stratosphere during the winter of 2015/2016. The observed distribution of reactive nitrogen shows clear indications of nitrification in mid-winter and denitrification in late winter. This was caused by the formation of polar stratospheric cloud particles, which were observed during several flights. The sedimentation and evaporation of these particles and the descent of air masses cause a redistribution of reactive nitrogen.
Sergey M. Khaykin, Elizabeth Moyer, Martina Krämer, Benjamin Clouser, Silvia Bucci, Bernard Legras, Alexey Lykov, Armin Afchine, Francesco Cairo, Ivan Formanyuk, Valentin Mitev, Renaud Matthey, Christian Rolf, Clare E. Singer, Nicole Spelten, Vasiliy Volkov, Vladimir Yushkov, and Fred Stroh
Atmos. Chem. Phys., 22, 3169–3189, https://doi.org/10.5194/acp-22-3169-2022, https://doi.org/10.5194/acp-22-3169-2022, 2022
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The Asian monsoon anticyclone is the key contributor to the global annual maximum in lower stratospheric water vapour. We investigate the impact of deep convection on the lower stratospheric water using a unique set of observations aboard the high-altitude M55-Geophysica aircraft deployed in Nepal in summer 2017 within the EU StratoClim project. We find that convective plumes of wet air can persist within the Asian anticyclone for weeks, thereby enhancing the occurrence of high-level clouds.
Rupert Holzinger, Oliver Eppers, Kouji Adachi, Heiko Bozem, Markus Hartmann, Andreas Herber, Makoto Koike, Dylan B. Millet, Nobuhiro Moteki, Sho Ohata, Frank Stratmann, and Atsushi Yoshida
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-95, https://doi.org/10.5194/acp-2022-95, 2022
Revised manuscript not accepted
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In spring 2018 the research aircraft Polar 5 conducted flights in the Arctic atmosphere. The flight operation was from Station Nord in Greenland, 1700 km north of the Arctic Circle (81°43'N, 17°47'W). Using a mass spectrometer we measured more than 100 organic compounds in the air. We found a clear signature of natural organic compounds that are transported from forests to the high Arctic. These compounds have the potential to change the cloud cover and energy budget of the Arctic region.
Valentin Lauther, Bärbel Vogel, Johannes Wintel, Andrea Rau, Peter Hoor, Vera Bense, Rolf Müller, and C. Michael Volk
Atmos. Chem. Phys., 22, 2049–2077, https://doi.org/10.5194/acp-22-2049-2022, https://doi.org/10.5194/acp-22-2049-2022, 2022
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We show airborne in situ measurements of the very short-lived ozone-depleting substances CH2Cl2 and CHCl3, revealing particularly high concentrations of both species in the lower stratosphere. Back-trajectory calculations and 3D model simulations show that the air masses with high concentrations originated in the Asian boundary layer and were transported via the Asian summer monsoon. We also identify a fast transport pathway into the stratosphere via the North American monsoon and by hurricanes.
Dina Khordakova, Christian Rolf, Jens-Uwe Grooß, Rolf Müller, Paul Konopka, Andreas Wieser, Martina Krämer, and Martin Riese
Atmos. Chem. Phys., 22, 1059–1079, https://doi.org/10.5194/acp-22-1059-2022, https://doi.org/10.5194/acp-22-1059-2022, 2022
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Extreme storms transport humidity from the troposphere to the stratosphere. Here it has a strong impact on the climate. With ongoing global warming, we expect more storms and, hence, an enhancement of this effect. A case study was performed in order to measure the impact of the direct injection of water vapor into the lower stratosphere. The measurements displayed a significant transport of water vapor into the lower stratosphere, and this was supported by satellite and reanalysis data.
Manuel Baumgartner, Christian Rolf, Jens-Uwe Grooß, Julia Schneider, Tobias Schorr, Ottmar Möhler, Peter Spichtinger, and Martina Krämer
Atmos. Chem. Phys., 22, 65–91, https://doi.org/10.5194/acp-22-65-2022, https://doi.org/10.5194/acp-22-65-2022, 2022
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An important mechanism for the appearance of ice particles in the upper troposphere at low temperatures is homogeneous nucleation. This process is commonly described by the
Koop line, predicting the humidity at freezing. However, laboratory measurements suggest that the freezing humidities are above the Koop line, motivating the present study to investigate the influence of different physical parameterizations on the homogeneous freezing with the help of a detailed numerical model.
Markus Jesswein, Heiko Bozem, Hans-Christoph Lachnitt, Peter Hoor, Thomas Wagenhäuser, Timo Keber, Tanja Schuck, and Andreas Engel
Atmos. Chem. Phys., 21, 17225–17241, https://doi.org/10.5194/acp-21-17225-2021, https://doi.org/10.5194/acp-21-17225-2021, 2021
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This study presents and compares inorganic chlorine (Cly) derived from observations with the HALO research aircraft in the Antarctic late winter–early fall 2019 and the Arctic winter 2015–2016. Trend-corrected correlations from the Northern Hemisphere show excellent agreement with those from the Southern Hemisphere. After observation allocation inside and outside the vortex based on N2O measurements, results of the two campaigns reveal substantial differences in Cly within the respective vortex.
Sho Ohata, Makoto Koike, Atsushi Yoshida, Nobuhiro Moteki, Kouji Adachi, Naga Oshima, Hitoshi Matsui, Oliver Eppers, Heiko Bozem, Marco Zanatta, and Andreas B. Herber
Atmos. Chem. Phys., 21, 15861–15881, https://doi.org/10.5194/acp-21-15861-2021, https://doi.org/10.5194/acp-21-15861-2021, 2021
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Vertical profiles of black carbon (BC) in the Arctic were measured during the PAMARCMiP aircraft-based experiment in spring 2018 and compared with those observed during previous aircraft campaigns in 2008, 2010, and 2015. Their differences were explained primarily by the year-to-year variation of biomass burning activities in northern midlatitudes over Eurasia. Our observations provide a bases to evaluate numerical model simulations that assess the BC radiative effects in the Arctic spring.
Yu-Wen Chen, Yi-Chun Chen, Charles C.-K. Chou, Hui-Ming Hung, Shih-Yu Chang, Lisa Eirenschmalz, Michael Lichtenstern, Helmut Ziereis, Hans Schlager, Greta Stratmann, Katharina Kaiser, Johannes Schneider, Stephan Borrmann, Florian Obersteiner, Eric Förster, Andreas Zahn, Wei-Nai Chen, Po-Hsiung Lin, Shuenn-Chin Chang, Maria Dolores Andrés Hernández, Pao-Kuan Wang, and John P. Burrows
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-788, https://doi.org/10.5194/acp-2021-788, 2021
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By presenting an approach using EMeRGe-Asia airborne field measurements and surface observations, this study shows that the fraction of OH reactivity due to SO2-OH reaction has a significant correlation with the sulfate concentration. Approximately 30 % of sulfate is produced by SO2-OH reaction. Our results underline the importance of SO2-OH gas-phase oxidation in sulfate formation, and demonstrate that the method can be applied to other regions and under different meteorological conditions.
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
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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.
Christoph Mahnke, Ralf Weigel, Francesco Cairo, Jean-Paul Vernier, Armin Afchine, Martina Krämer, Valentin Mitev, Renaud Matthey, Silvia Viciani, Francesco D'Amato, Felix Ploeger, Terry Deshler, and Stephan Borrmann
Atmos. Chem. Phys., 21, 15259–15282, https://doi.org/10.5194/acp-21-15259-2021, https://doi.org/10.5194/acp-21-15259-2021, 2021
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In 2017, in situ aerosol measurements were conducted aboard the M55 Geophysica in the Asian monsoon region. The vertical particle mixing ratio profiles show a distinct layer (15–18.5 km), the Asian tropopause aerosol layer (ATAL). The backscatter ratio (BR) was calculated based on the aerosol size distributions and compared with the BRs detected by a backscatter probe and a lidar aboard M55, and by the CALIOP lidar. All four methods show enhanced BRs in the ATAL altitude range (max. at 17.5 km).
Prashant Chavan, Suvarna Fadnavis, Tanusri Chakroborty, Christopher E. Sioris, Sabine Griessbach, and Rolf Müller
Atmos. Chem. Phys., 21, 14371–14384, https://doi.org/10.5194/acp-21-14371-2021, https://doi.org/10.5194/acp-21-14371-2021, 2021
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Biomass burning (BB) over Asia is a strong source of carbonaceous aerosols during spring. Here, we show an outflow of Asian BB carbonaceous aerosols into the UTLS. These aerosols enhance atmospheric heating and produce circulation changes that lead to the enhancement of water vapor in the UTLS over the tropics. In the stratosphere, water vapor is further transported to the South Pole by the Brewer–Dobson circulation. Enhancement of water vapor in the UTLS has implications for climate change.
Julia Schneider, Kristina Höhler, Robert Wagner, Harald Saathoff, Martin Schnaiter, Tobias Schorr, Isabelle Steinke, Stefan Benz, Manuel Baumgartner, Christian Rolf, Martina Krämer, Thomas Leisner, and Ottmar Möhler
Atmos. Chem. Phys., 21, 14403–14425, https://doi.org/10.5194/acp-21-14403-2021, https://doi.org/10.5194/acp-21-14403-2021, 2021
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Homogeneous freezing is a relevant mechanism for the formation of cirrus clouds in the upper troposphere. Based on an extensive set of homogeneous freezing experiments at the AIDA chamber with aqueous sulfuric acid aerosol, we provide a new fit line for homogeneous freezing onset conditions of sulfuric acid aerosol focusing on cirrus temperatures. In the atmosphere, homogeneous freezing thresholds have important implications on the cirrus cloud occurrence and related cloud radiative effects.
Jayanarayanan Kuttippurath, Wuhu Feng, Rolf Müller, Pankaj Kumar, Sarath Raj, Gopalakrishna Pillai Gopikrishnan, and Raina Roy
Atmos. Chem. Phys., 21, 14019–14037, https://doi.org/10.5194/acp-21-14019-2021, https://doi.org/10.5194/acp-21-14019-2021, 2021
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The Arctic winter/spring 2020 was one of the coldest with a strong and long-lasting vortex, high chlorine activation, severe denitrification, and unprecedented ozone loss. The loss was even equal to the levels of some of the warm Antarctic winters. Total column ozone values below 220 DU for several weeks and ozone loss saturation were observed during the period. These results show an unusual meteorology and warrant dedicated studies on the impact of climate change on ozone loss.
Ralf Weigel, Christoph Mahnke, Manuel Baumgartner, Martina Krämer, Peter Spichtinger, Nicole Spelten, Armin Afchine, Christian Rolf, Silvia Viciani, Francesco D'Amato, Holger Tost, and Stephan Borrmann
Atmos. Chem. Phys., 21, 13455–13481, https://doi.org/10.5194/acp-21-13455-2021, https://doi.org/10.5194/acp-21-13455-2021, 2021
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In July and August 2017, the StratoClim mission took place in Nepal with eight flights of the M-55 Geophysica at up to 20 km in the Asian monsoon anticyclone. New particle formation (NPF) next to cloud ice was detected in situ by abundant nucleation-mode aerosols (> 6 nm) along with ice particles (> 3 µm). NPF was observed mainly below the tropopause, down to 15 % being non-volatile residues. Observed intra-cloud NPF indicates its importance for the composition in the tropical tropopause layer.
Luca Palchetti, Marco Barucci, Claudio Belotti, Giovanni Bianchini, Bertrand Cluzet, Francesco D'Amato, Samuele Del Bianco, Gianluca Di Natale, Marco Gai, Dina Khordakova, Alessio Montori, Hilke Oetjen, Markus Rettinger, Christian Rolf, Dirk Schuettemeyer, Ralf Sussmann, Silvia Viciani, Hannes Vogelmann, and Frank Gunther Wienhold
Earth Syst. Sci. Data, 13, 4303–4312, https://doi.org/10.5194/essd-13-4303-2021, https://doi.org/10.5194/essd-13-4303-2021, 2021
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The FIRMOS far-infrared (IR) prototype, developed for the preparation of the ESA FORUM mission, was deployed for the first time at Mt. Zugspitze at 3000 m altitude to measure the far-IR spectrum of atmospheric emissions. The measurements, including co-located radiometers, lidars, radio soundings, weather, and surface properties, provide a unique dataset to study radiative properties of water vapour, cirrus clouds, and snow emissivity over the IR emissions, including the under-explored far-IR.
Ralf Weigel, Christoph Mahnke, Manuel Baumgartner, Antonis Dragoneas, Bärbel Vogel, Felix Ploeger, Silvia Viciani, Francesco D'Amato, Silvia Bucci, Bernard Legras, Beiping Luo, and Stephan Borrmann
Atmos. Chem. Phys., 21, 11689–11722, https://doi.org/10.5194/acp-21-11689-2021, https://doi.org/10.5194/acp-21-11689-2021, 2021
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In July and August 2017, eight StratoClim mission flights of the Geophysica reached up to 20 km in the Asian monsoon anticyclone. New particle formation (NPF) was identified in situ by abundant nucleation-mode aerosols (6–15 nm in diameter) with mixing ratios of up to 50 000 mg−1. NPF occurred most frequently at 12–16 km with fractions of non-volatile residues of down to 15 %. Abundance and productivity of observed NPF indicate its ability to promote the Asian tropopause aerosol layer.
Thorsten Kaluza, Daniel Kunkel, and Peter Hoor
Weather Clim. Dynam., 2, 631–651, https://doi.org/10.5194/wcd-2-631-2021, https://doi.org/10.5194/wcd-2-631-2021, 2021
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We present a 10-year analysis on the occurrence of strong wind shear in the Northern Hemisphere, focusing on the region around the transport barrier that separates the first two layers of the atmosphere. The major result of our analysis is that strong wind shear above a certain threshold occurs frequently and nearly exclusively in this region, which, as an indicator for turbulent mixing, might have major implications concerning the separation efficiency of the transport barrier.
Lukas Krasauskas, Jörn Ungermann, Peter Preusse, Felix Friedl-Vallon, Andreas Zahn, Helmut Ziereis, Christian Rolf, Felix Plöger, Paul Konopka, Bärbel Vogel, and Martin Riese
Atmos. Chem. Phys., 21, 10249–10272, https://doi.org/10.5194/acp-21-10249-2021, https://doi.org/10.5194/acp-21-10249-2021, 2021
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A Rossby wave (RW) breaking event was observed over the North Atlantic during the WISE measurement campaign in October 2017. Infrared limb sounding measurements of trace gases in the lower stratosphere, including high-resolution 3-D tomographic reconstruction, revealed complex spatial structures in stratospheric tracers near the polar jet related to previous RW breaking events. Backward-trajectory analysis and tracer correlations were used to study mixing and stratosphere–troposphere exchange.
Nuria Pilar Plaza, Aurélien Podglajen, Cristina Peña-Ortiz, and Felix Ploeger
Atmos. Chem. Phys., 21, 9585–9607, https://doi.org/10.5194/acp-21-9585-2021, https://doi.org/10.5194/acp-21-9585-2021, 2021
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We study the role of different processes in setting the lower stratospheric water vapour. We find that mechanisms involving ice microphysics and small-scale mixing produce the strongest increase in water vapour, in particular over the Asian Monsoon. Small-scale mixing has a special relevance as it improves the agreement with observations at seasonal and intra-seasonal timescales, contrary to the North American Monsoon case, in which large-scale temperatures still dominate its variability.
Marco Zanatta, Andreas Herber, Zsófia Jurányi, Oliver Eppers, Johannes Schneider, and Joshua P. Schwarz
Atmos. Chem. Phys., 21, 9329–9342, https://doi.org/10.5194/acp-21-9329-2021, https://doi.org/10.5194/acp-21-9329-2021, 2021
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Saline snow samples were collected from the sea ice in the Fram Strait. Laboratory experiments revealed that sea salt can bias the quantification of black carbon with a laser-induced incandescence technique. The maximum underestimation was quantified to reach values of 80 %–90 %. This salt-induced interference is reported here for the first time and should be considered in future studies aiming to quantify black carbon in snow in marine environments.
Felix Ploeger, Mohamadou Diallo, Edward Charlesworth, Paul Konopka, Bernard Legras, Johannes C. Laube, Jens-Uwe Grooß, Gebhard Günther, Andreas Engel, and Martin Riese
Atmos. Chem. Phys., 21, 8393–8412, https://doi.org/10.5194/acp-21-8393-2021, https://doi.org/10.5194/acp-21-8393-2021, 2021
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We investigate the global stratospheric circulation (Brewer–Dobson circulation) in the new ECMWF ERA5 reanalysis based on age of air simulations, and we compare it to results from the preceding ERA-Interim reanalysis. Our results show a slower stratospheric circulation and higher age for ERA5. The age of air trend in ERA5 over the 1989–2018 period is negative throughout the stratosphere, related to multi-annual variability and a potential contribution from changes in the reanalysis system.
Gerald Wetzel, Felix Friedl-Vallon, Norbert Glatthor, Jens-Uwe Grooß, Thomas Gulde, Michael Höpfner, Sören Johansson, Farahnaz Khosrawi, Oliver Kirner, Anne Kleinert, Erik Kretschmer, Guido Maucher, Hans Nordmeyer, Hermann Oelhaf, Johannes Orphal, Christof Piesch, Björn-Martin Sinnhuber, Jörn Ungermann, and Bärbel Vogel
Atmos. Chem. Phys., 21, 8213–8232, https://doi.org/10.5194/acp-21-8213-2021, https://doi.org/10.5194/acp-21-8213-2021, 2021
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Measurements of the pollutants C2H6, C2H2, HCOOH, and PAN were performed in the North Atlantic UTLS region with the airborne limb imager GLORIA in 2017. Enhanced amounts of these species were detected in the upper troposphere and even in the lowermost stratosphere (PAN). Main sources of these gases are forest fires in North America and anthropogenic pollution in South Asia. Simulations of EMAC and CAMS are qualitatively able to reproduce the measured data but underestimate the absolute amounts.
Romain Blot, Philippe Nedelec, Damien Boulanger, Pawel Wolff, Bastien Sauvage, Jean-Marc Cousin, Gilles Athier, Andreas Zahn, Florian Obersteiner, Dieter Scharffe, Hervé Petetin, Yasmine Bennouna, Hannah Clark, and Valérie Thouret
Atmos. Meas. Tech., 14, 3935–3951, https://doi.org/10.5194/amt-14-3935-2021, https://doi.org/10.5194/amt-14-3935-2021, 2021
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A lack of information about temporal changes in measurement uncertainties is an area of concern for long-term trend studies of the key compounds which have a direct or indirect impact on climate change. The IAGOS program has measured O3 and CO within the troposphere and lower stratosphere for more than 25 years. In this study, we demonstrated that the IAGOS database can be treated as one continuous program and is therefore appropriate for studies of long-term trends.
Mohamadou Diallo, Manfred Ern, and Felix Ploeger
Atmos. Chem. Phys., 21, 7515–7544, https://doi.org/10.5194/acp-21-7515-2021, https://doi.org/10.5194/acp-21-7515-2021, 2021
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Despite good agreement in the spatial structure, there are substantial differences in the strength of the Brewer–Dobson circulation (BDC) and its modulations in the UTLS and upper stratosphere. The tropical upwelling is generally weaker in ERA5 than in ERAI due to weaker planetary and gravity wave breaking in the UTLS. Analysis of the BDC trend shows an acceleration of the BDC of about 1.5 % decade-1 due to the long-term intensification in wave breaking, consistent with climate predictions.
Cited articles
Adcock, K. E., Fraser, P. J., Hall, B. D., Langenfelds, R. L., Lee, G., Montzka, S. A., Oram, D. E., Röckmann, T., Stroh, F., Sturges, W. T., Vogel, B., and Laube, J. C.: Aircraft-Based Observations of Ozone-Depleting Substances in the Upper Troposphere and Lower Stratosphere in and Above the Asian Summer Monsoon, J. Geophys. Res., 126, e2020JD033137, https://doi.org/10.1029/2020JD033137, 2021. a, b, c, d, e, f, g, h
An, M., Western, L. M., Say, D., Chen, L., Claxton, T., Ganesan, A. L., Hossaini, R., Krummel, P. B., Manning, A. J., Mühle, J., O'Doherty, S., Prinn, R. G., Weiss, R. F., Young, D., Hu, J., Yao, B., and Rigby, M.: Rapid increase in dichloromethane emissions from China inferred through atmospheric observations, Nat. Commun., 12, https://doi.org/10.1038/s41467-021-27592-y, 2021. a, b
Angelino, S., Suess, D. T., and Prather, K. A.: Formation of Aerosol Particles from Reactions of Secondary and Tertiary Alkylamines: Characterization by Aerosol Time-of-Flight Mass Spectrometry, Environ. Sci. Technol., 35, 3130–3138, https://doi.org/10.1021/es0015444, 2001. a
Appel, O., Köllner, F., Dragoneas, A., Hünig, A., Molleker, S., Schlager, H., Mahnke, C., Weigel, R., Port, M., Schulz, C., Drewnick, F., Vogel, B., Stroh, F., and Borrmann, S.: Chemical analysis of the Asian tropopause aerosol layer (ATAL) with emphasis on secondary aerosol particles using aircraft-based in situ aerosol mass spectrometry, Atmos. Chem. Phys., 22, 13607–13630, https://doi.org/10.5194/acp-22-13607-2022, 2022. a, b, c, d
Bak, J., Kim, J., Koo, J.-H., Pan, L. L., Ryoo, J.-M., Newman, P. A., Franchin, A., Liu, X., Abad, G. G., Lee, H.-J., Jeon, W., and Kim, C.-H.: An Integrated Analysis of Ozone and Carbon Monoxide Over the Western Pacific Using Satellite and Aircraft Measurements During the ACCLIP Summer Campaign 2022, J. Geophys. Res., 130, e2024JD042771, https://doi.org/10.1029/2024JD042771, 2025. a
Baker, A. K., Schuck, T. J., Brenninkmeijer, C. A. M., Rauthe-Schöch, A., Slemr, F., van Velthoven, P. F. J., and Lelieveld, J.: Estimating the contribution of monsoon-related biogenic production to methane emissions from South Asia using CARIBIC observations, Geophys. Res. Lett., 39, https://doi.org/10.1029/2012GL051756, 2012. a
Becker, F., Vogel, B., Günther, G., Ploeger, F., Riese, M., Rosanka, S., Taraborrelli, D., Nützel, M., Jöckel, P., Brinkop, S., and Müller, R.: Upward transport of boundary layer air to altitudes of the Asian summer monsoon anticyclone in Eulerian and Lagrangian model simulations, Meteorol. Z., 3, 195–211, https://doi.org/10.1127/metz/1266, 2025. a
Bhatia, K., Baker, A., Yang, W., Vecchi, G., Knutson, T., Murakami, H., Kossin, J., Hodges, K., Dixon, K., Bronselaer, B., and Whitlock, C.: A potential explanation for the global increase in tropical cyclone rapid intensification, Nat. Commun., 13, 6626, https://doi.org/10.1038/s41467-022-34321-6, 2022. a
Bian, J., Li, D., Bai, Z., Li, Q., Lyu, D., and Zhou, X.: Transport of Asian surface pollutants to the global stratosphere from the Tibetan Plateau region during the Asian summer monsoon, Natl. Sci. Rev., 7, 516–533, https://doi.org/10.1093/nsr/nwaa005, 2020. a
Bönisch, H., Engel, A., Curtius, J., Birner, Th., and Hoor, P.: Quantifying transport into the lowermost stratosphere using simultaneous in-situ measurements of SF6 and CO2, Atmos. Chem. Phys., 9, 5905–5919, https://doi.org/10.5194/acp-9-5905-2009, 2009. a
Brunamonti, S., Jorge, T., Oelsner, P., Hanumanthu, S., Singh, B. B., Kumar, K. R., Sonbawne, S., Meier, S., Singh, D., Wienhold, F. G., Luo, B. P., Boettcher, M., Poltera, Y., Jauhiainen, H., Kayastha, R., Karmacharya, J., Dirksen, R., Naja, M., Rex, M., Fadnavis, S., and Peter, T.: Balloon-borne measurements of temperature, water vapor, ozone and aerosol backscatter on the southern slopes of the Himalayas during StratoClim 2016–2017, Atmos. Chem. Phys., 18, 15937–15957, https://doi.org/10.5194/acp-18-15937-2018, 2018. a, b
Chirkov, M., Stiller, G. P., Laeng, A., Kellmann, S., von Clarmann, T., Boone, C. D., Elkins, J. W., Engel, A., Glatthor, N., Grabowski, U., Harth, C. M., Kiefer, M., Kolonjari, F., Krummel, P. B., Linden, A., Lunder, C. R., Miller, B. R., Montzka, S. A., Mühle, J., O'Doherty, S., Orphal, J., Prinn, R. G., Toon, G., Vollmer, M. K., Walker, K. A., Weiss, R. F., Wiegele, A., and Young, D.: Global HCFC-22 measurements with MIPAS: retrieval, validation, global distribution and its evolution over 2005–2012, Atmos. Chem. Phys., 16, 3345–3368, https://doi.org/10.5194/acp-16-3345-2016, 2016. a
Claxton, T., Hossaini, R., Wild, O., Chipperfield, M. P., and Wilson, C.: On the Regional and Seasonal Ozone Depletion Potential of Chlorinated Very Short-Lived Substances, Geophys. Res. Lett., 46, 5489–5498, https://doi.org/10.1029/2018GL081455, 2019. a
Clemens, J., Ploeger, F., Konopka, P., Portmann, R., Sprenger, M., and Wernli, H.: Characterization of transport from the Asian summer monsoon anticyclone into the UTLS via shedding of low potential vorticity cutoffs, Atmos. Chem. Phys., 22, 3841–3860, https://doi.org/10.5194/acp-22-3841-2022, 2022. a
Clemens, J., Hoffmann, L., Vogel, B., Grießbach, S., and Thomas, N.: Implementation and evaluation of diabatic advection in the Lagrangian transport model MPTRAC 2.6, Geosci. Model Dev., 17, 4467–4493, https://doi.org/10.5194/gmd-17-4467-2024, 2024a. a
Clemens, J., Vogel, B., Hoffmann, L., Griessbach, S., Thomas, N., Fadnavis, S., Müller, R., Peter, T., and Ploeger, F.: A multi-scenario Lagrangian trajectory analysis to identify source regions of the Asian tropopause aerosol layer on the Indian subcontinent in August 2016, Atmos. Chem. Phys., 24, 763–787, https://doi.org/10.5194/acp-24-763-2024, 2024b. a, b, c, d, e
Dethof, A., O'Neill, A., Slingo, J. M., and Smit, H. G. J.: A mechanism for moistening the lower stratosphere involving the Asian summer monsoon, Q. J. Roy. Meteor. Soc., 556, 1079–1106, 1999. a
Dubé, K., Tegtmeier, S., Bourassa, A., Laube, J. C., Engel, A., Saunders, L. N., Walker, K. A., Hossaini, R., and Bednarz, E. M.: Chlorinated very short-lived substances offset the long-term reduction of inorganic stratospheric chlorine, Commun. Earth Environ., 6, 487, https://doi.org/10.1038/s43247-025-02478-9, 2025. a
Ekinci, F., Eppers, O., Appel, O., Ploeger, F., Dragoneas, A., Molleker, S., Brauner, P., Lachnitt, H.-C., Weyland, F., Ort, L., Emig, N., Clemen, H.-C., Tomsche, L., Ebert, M., Hoor, P., Vogel, B., Cheng, Y., Schneider, J., Borrmann, S., and Köllner, F.: Enhancement of ammonium nitrate aerosol in the Northern Hemisphere lower stratosphere linked to Asian summer monsoon outflow, EGUsphere [preprint], https://doi.org/10.5194/egusphere-2026-998, 2026. a
Emanuel, K.: Tropical cyclons, Annu. Rev. Earth Pl. Sc., 3, 75–104, 2003. a
Emanuel, K.: Increasing destructiveness of tropical cyclones over the past 30 years, Nature, 436, 686–688, https://doi.org/10.1038/nature03906, 2005. a
Eppers, O., Köllner, F., Appel, O., Brauner, P., Ekinci, F., Molleker, S., Dragoneas, A., Smith, W. P., Ueyama, R., Bucci, S., Legras, B., Williamson, C., Campos, T., Ullman, K., Schill, G. P., Murphy, D. M., Pan, L. L., Cheng, Y., and Borrmann, S.: Regional contributions to the chemical composition of the Asian tropopause aerosol layer (ATAL, ESS Open Archive, https://doi.org/10.22541/essoar.175130383.35260852/v1, 2025. a
Facchini, M. C., Decesari, S., Rinaldi, M., Carbone, C., Finessi, E., Mircea, M., Fuzzi, S., Moretti, F., Tagliavini, E., Ceburnis, D., and O'Dowd, C. D.: Important Source of Marine Secondary Organic Aerosol from Biogenic Amines, Environ. Sci. Technol., 42, 9116–9121, https://doi.org/10.1021/es8018385, 2008. a
Fadnavis, S., Sagalgile, A., Sonbawne, S., Vogel, B., Peter, T., Wienhold, F. G., Dirksen, R., Oelsner, P., Naja, M., and Müller, R.: Comparison of ozonesonde measurements in the upper troposphere and lower Stratosphere in Northern India with reanalysis and chemistry-climate-model data, Sci. Rep., 13, https://doi.org/10.1038/s41598-023-34330-5, 2023. a
Fadnavis, S., Sonbawne, S. M., Laakso, A., Ploeger, F., Rap, A., Heinold, B., Sabin, T. P., and Müller, R.: Long range transport of South and East Asian anthropogenic aerosols counteracting Arctic warming, npj Climate and Atmospheric Science, 7, https://doi.org/10.1038/s41612-024-00633-1, 2024. a
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. a, b
Garny, H. and Randel, W. J.: Dynamic variability of the Asian monsoon anticyclone observed in potential vorticity and correlations with tracer distributions, J. Geophys. Res., 118, 13421–13433, https://doi.org/10.1002/2013JD020908, 2013. a
Ge, X., Wexler, A. S., and Clegg, S. L.: Atmospheric amines – Part I. A review, Atmos. Environ., 45, 524–546, https://doi.org/10.1016/j.atmosenv.2010.10.012, 2011. a, b
Gettelman, A. and de Forster, P. M.: Definition and climatology of the tropical tropopause layer, J. Meteorol. Soc. Jpn., 80, 911–924, 2002. a
Gibb, S. W., Mantoura, R. F. C., and Liss, P. S.: Ocean-atmosphere exchange and atmospheric speciation of ammonia and methylamines in the region of the NW Arabian Sea, Global Biogeochem. Cy., 13, 161–178, https://doi.org/10.1029/98GB00743, 1999. a
Gottschaldt, K.-D., Schlager, H., Baumann, R., Bozem, H., Eyring, V., Hoor, P., Jöckel, P., Jurkat, T., Voigt, C., Zahn, A., and Ziereis, H.: Trace gas composition in the Asian summer monsoon anticyclone: a case study based on aircraft observations and model simulations, Atmos. Chem. Phys., 17, 6091–6111, https://doi.org/10.5194/acp-17-6091-2017, 2017. a
Graßl, S., Ritter, C., Tritscher, I., and Vogel, B.: Does the Asian summer monsoon play a role in the stratospheric aerosol budget of the Arctic?, Atmos. Chem. Phys., 24, 7535–7557, https://doi.org/10.5194/acp-24-7535-2024, 2024. a
Hanumanthu, S., Vogel, B., Müller, R., Brunamonti, S., Fadnavis, S., Li, D., Ölsner, P., Naja, M., Singh, B. B., Kumar, K. R., Sonbawne, S., Jauhiainen, H., Vömel, H., Luo, B., Jorge, T., Wienhold, F. G., Dirkson, R., and Peter, T.: Strong day-to-day variability of the Asian Tropopause Aerosol Layer (ATAL) in August 2016 at the Himalayan foothills, Atmos. Chem. Phys., 20, 14273–14302, https://doi.org/10.5194/acp-20-14273-2020, 2020. a, b
Healy, R. M., Evans, G. J., Murphy, M., Sierau, B., Arndt, J., McGillicuddy, E., O'Connor, I. P., Sodeau, J. R., and Wenger, J. C.: Single-particle speciation of alkylamines in ambient aerosol at five European sites, Anal. Bioanal. Chem., 407, 1618–2650, https://doi.org/10.1007/s00216-014-8092-1, 2015. a
Hegglin, M. I. and Shepherd, T. G.: O3-N2O correlations from the Atmospheric Chemistry Experiment: Revisiting a diagnostic of transport and chemistry in the stratosphere, J. Geophys. Res., 112, D19301, https://doi.org/10.1029/2006JD008281, 2007. a, b
Hersbach, H., Bell, B., Berrisford, P., Hirahara, S., Horànyi, 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., Janiskovà, 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. a
Hoffmann, L. and Spang, R.: An assessment of tropopause characteristics of the ERA5 and ERA-Interim meteorological reanalyses, Atmos. Chem. Phys., 22, 4019–4046, https://doi.org/10.5194/acp-22-4019-2022, 2022. a
Hoffmann, L., Günther, G., Li, D., Stein, O., Wu, X., Griessbach, S., Heng, Y., Konopka, P., Müller, R., Vogel, B., and Wright, J. S.: From ERA-Interim to ERA5: the considerable impact of ECMWF's next-generation reanalysis on Lagrangian transport simulations, Atmos. Chem. Phys., 19, 3097–3124, https://doi.org/10.5194/acp-19-3097-2019, 2019. a
Hoor, P., Fischer, H., Lange, L., Lelieveld, J., and Brunner, D.: Seasonal variations of a mixing layer in the lowermost stratosphere as identified by the CO-O3 correlation from in situ measurements, J. Geophys. Res., 107, 4044, https://doi.org/10.1029/2000JD000289, 2002. a
Höpfner, M., Ungermann, J., Borrmann, S., Wagner, R., Spang, R., Riese, M., Stiller, G., Appel, O., Batenburg, A. M., Bucci, S., Cairo, F., Dragoneas, A., Friedl-Vallon, F., Hünig, A., Johansson, S., Krasauskas, L., Legras, B., Leisner, T., Mahnke, C., Möhler, O., Molleker, S., Müller, R., Neubert, T., Orphal, J., Preusse, P., Rex, M., Saathoff, H., Stroh, F., Weigel, R., and Wohltmann, I.: Ammonium nitrate particles formed in upper troposphere from ground ammonia sources during Asian monsoons, Nat. Geosci., 12, 608–612, https://doi.org/10.1038/s41561-019-0385-8, 2019. a, b, c
Hossaini, R., Chipperfield, M. P., Montzka, S. A., Leeson, A. A., Dhomse, S. S., and Pyle, J. A.: The increasing threat to stratospheric ozone from dichloromethane, Nat. Commun., 8, 15962, https://doi.org/10.1038/ncomms15962, 2017. a
Hünig, A., Appel, O., Dragoneas, A., Molleker, S., Clemen, H.-C., Helleis, F., Klimach, T., Köllner, F., Böttger, T., Drewnick, F., Schneider, J., and Borrmann, S.: Design, characterization, and first field deployment of a novel aircraft-based aerosol mass spectrometer combining the laser ablation and flash vaporization techniques, Atmos. Meas. Tech., 15, 2889–2921, https://doi.org/10.5194/amt-15-2889-2022, 2022. a
Jesswein, M., Lauther, V., Emig, N., Hoor, P., Keber, T., Lachnitt, H.-C., Ort, L., Schuck, T., Strobel, J., Van Luijt, R., Volk, C. M., Weyland, F., and Engel, A.: Tracing elevated abundance of CH2Cl2 in the subarctic upper troposphere to the Asian Summer Monsoon, Atmos. Chem. Phys., 25, 8107–8126, https://doi.org/10.5194/acp-25-8107-2025, 2025. a, b, c
Kachula, O., Vogel, B., Günther, G., and Müller, R.: An optimization-based approach to track the Asian summer monsoon anticyclone across daily and interannual variability, Atmos. Chem. Phys., 25, 15171–15195, https://doi.org/10.5194/acp-25-15171-2025, 2025. a, b, c
Knutson, T., Camargo, S. J., Chan, J. C. L., Emanuel, K., Ho, C.-H., Kossin, J., Mohapatra, M., Satoh, M., Sugi, M., Walsh, K., and Wu, L.: Tropical Cyclones and Climate Change Assessment: Part II: Projected Response to Anthropogenic Warming, B. Am. Meteorol. Soc., 101, E303–E322, https://doi.org/10.1175/BAMS-D-18-0194.1, 2020. a
Köllner, F., Schneider, J., Willis, M. D., Klimach, T., Helleis, F., Bozem, H., Kunkel, D., Hoor, P., Burkart, J., Leaitch, W. R., Aliabadi, A. A., Abbatt, J. P. D., Herber, A. B., and Borrmann, S.: Particulate trimethylamine in the summertime Canadian high Arctic lower troposphere, Atmos. Chem. Phys., 17, 13747–13766, https://doi.org/10.5194/acp-17-13747-2017, 2017. a
Köllner, F., Kohl, M., Ekinci, F., Eppers, O., Schneider, J., Dragoneas, A., M., S., Johansson, S., Ungermann, J., Kretschmer, E., Höpfner, M., Lauther, V., Volk, C. M., Appel, O., Brauner, P., Kunkel, D., Lachnitt, H.-C., Bozem, H., Weyland, F., Emig, N., Ort, L., Zahn, A., Tomsche, L., Pozzer, A., Lelieveld, J., Cheng, Y., Riese, M., Hoor, P., and Borrmann: Aerosol from the Asian monsoon ubiquitous throughout the extratropical stratosphere, Commun. Earth Eniron., https://doi.org/10.31223/X5RB46, under review, EarthArXiv [preprint], 2026. a, b
Konopka, P., Günther, G., Müller, R., dos Santos, F. H. S., Schiller, C., Ravegnani, F., Ulanovsky, A., Schlager, H., Volk, C. M., Viciani, S., Pan, L. L., McKenna, D.-S., and Riese, M.: Contribution of mixing to upward transport across the tropical tropopause layer (TTL), Atmos. Chem. Phys., 7, 3285–3308, https://doi.org/10.5194/acp-7-3285-2007, 2007. a
Konopka, P., Tao, M., Ploeger, F., Diallo, M., and Riese, M.: Tropospheric mixing and parametrization of unresolved convective updrafts as implemented in the Chemical Lagrangian Model of the Stratosphere (CLaMS v2.0), Geosci. Model Dev., 12, 2441–2462, https://doi.org/10.5194/gmd-12-2441-2019, 2019. a
Konopka, P., Tao, M., von Hobe, M., Hoffmann, L., Kloss, C., Ravegnani, F., Volk, C. M., Lauther, V., Zahn, A., Hoor, P., and Ploeger, F.: Tropospheric transport and unresolved convection: numerical experiments with CLaMS 2.0/MESSy, Geosci. Model Dev., 15, 7471–7487, https://doi.org/10.5194/gmd-15-7471-2022, 2022. a
Krämer, M., Rolf, C., Luebke, A., Afchine, A., Spelten, N., Costa, A., Meyer, J., Zöger, M., Smith, J., Herman, R. L., Buchholz, B., Ebert, V., Baumgardner, D., Borrmann, S., Klingebiel, M., and Avallone, L.: A microphysics guide to cirrus clouds – Part 1: Cirrus types, Atmos. Chem. Phys., 16, 3463–3483, https://doi.org/10.5194/acp-16-3463-2016, 2016. a
Kunkel, D., Hoor, P., Kaluza, T., Ungermann, J., Kluschat, B., Giez, A., Lachnitt, H.-C., Kaufmann, M., and Riese, M.: Evidence of small-scale quasi-isentropic mixing in ridges of extratropical baroclinic waves, Atmos. Chem. Phys., 19, 12607–12630, https://doi.org/10.5194/acp-19-12607-2019, 2019. a
Kunz, A., Sprenger, M., and Wernli, H.: Climatology of potential vorticity streamers and associated isentropic transport pathways across PV gradient barriers, J. Geophys. Res., 120, 3802–3821, https://doi.org/10.1002/2014JD022615, 2014JD022615, 2015. a, b
Laube, J. C., Schuck, T. J., Baartman, S., Chen, H., Geldenhuys, M., van Heuven, S., Keber, T., Popa, M. E., Tuffnell, E., Voet, F., Vogel, B., Wagenhäuser, T., Zanchetta, A., and Engel, A.: Vertical distribution of halogenated trace gases in the summer Arctic stratosphere based on two independent air sampling methods, Atmos. Meas. Tech., 18, 4087–4102, https://doi.org/10.5194/amt-18-4087-2025, 2025. a
Lauther, V., Vogel, B., Wintel, J., Rau, A., Hoor, P., Bense, V., Müller, R., and Volk, C. M.: In situ observations of CH2Cl2 and CHCl3 show efficient transport pathways for very short-lived species into the lower stratosphere via the Asian and the North American summer monsoon, Atmos. Chem. Phys., 22, 2049–2077, https://doi.org/10.5194/acp-22-2049-2022, 2022. a, b, c, d, e, f, g
Li, D., Vogel, B., Bian, J., Müller, R., Pan, L. L., Günther, G., Bai, Z., Li, Q., Zhang, J., Fan, Q., and Vömel, H.: Impact of typhoons on the composition of the upper troposphere within the Asian summer monsoon anticyclone: the SWOP campaign in Lhasa 2013, Atmos. Chem. Phys., 17, 4657–4672, https://doi.org/10.5194/acp-17-4657-2017, 2017. a, b, c, d, e
Li, D., Vogel, B., Müller, R., Bian, J., Günther, G., Li, Q., Zhang, J., Bai, Z., Vömel, H., and Riese, M.: High tropospheric ozone in Lhasa within the Asian summer monsoon anticyclone in 2013: influence of convective transport and stratospheric intrusions, Atmos. Chem. Phys., 18, 17979–17994, https://doi.org/10.5194/acp-18-17979-2018, 2018. a
Li, D., Vogel, B., Müller, R., Bian, J., Günther, G., Ploeger, F., Li, Q., Zhang, J., Bai, Z., Vömel, H., and Riese, M.: Dehydration and low ozone in the tropopause layer over the Asian monsoon caused by tropical cyclones: Lagrangian transport calculations using ERA-Interim and ERA5 reanalysis data, Atmos. Chem. Phys., 20, 4133–4152, https://doi.org/10.5194/acp-20-4133-2020, 2020. a, b, c, d, e, f
Li, D., Vogel, B., Müller, R., Bian, J., Günther, G., and Riese, M.: Tropical Cyclones Reduce Ozone in the Tropopause Region Over the Western Pacific: An Analysis of 18 Years Ozonesonde Profiles, Earths Future, 9, 1–9, https://doi.org/10.1029/2020EF001635, 2021. a, b
Li, D., Bian, J., Zhang, X., Vogel, B., Müller, R., and Gn̈ther, G.: Impact of typhoon Soudelor on ozone and water vapor in the Asian monsoon anticyclone western Pacific mode, Atmos. Sci. Lett., 24, e1147, https://doi.org/10.1002/asl.1147, 2023. a, b, c
Li, Q., Jiang, J. H., Wu, D. L., Read, W. G., Livesey, N. J., Waters, J. W., Zhang, Y., Wang, B., Filipiak, M. J., Davis, C. P., Turquety, S., Wu, S., Park, R. J., Yantosca, R. M., and Jacob, D. J.: Convective outflow of South Asian pollution: A global CTM simulation compared with EOS MLS observations, Geophys. Res. Lett., 32, L14826, https://doi.org/10.1029/2005GL022762, 2005. a
Malakar, P., Kesarkar, A., Bhate, J., Singh, V., and Deshamukhya, A.: Comparison of Reanalysis Data Sets to Comprehend the Evolution of Tropical Cyclones Over North Indian Ocean, Earth Space Sci., 7, e2019EA000978, https://doi.org/10.1029/2019EA000978, 2020. a
Mason, R. B. and Anderson, C. E.: The development and decay of the 100-mb. summertime anticyclone over southern Asia, Mon. Weather Rev., 91, 3–12, https://doi.org/10.1175/1520-0493(1963)091<0003:TDADOT>2.3.CO;2, 1963. a
Matsuura, T., Yumoto, M., and Iizuka, S.: A mechanism of interdecadal variability of tropical cyclone activity over the western North Pacific, Clim. Dynam., 21, 105–117, https://doi.org/10.1007/s00382-003-0327-3, 2003. a
McKenna, D. S., Grooß, J.-U., Günther, G., Konopka, P., Müller, R., Carver, G., and Sasano, Y.: A new Chemical Lagrangian Model of the Stratosphere (CLaMS): 2. Formulation of chemistry scheme and initialization, J. Geophys. Res., 107, 4256, https://doi.org/10.1029/2000JD000113, 2002a. a
McKenna, D. S., Konopka, P., Grooß, J.-U., Günther, G., Müller, R., Spang, R., Offermann, D., and Orsolini, Y.: A new Chemical Lagrangian Model of the Stratosphere (CLaMS): 1. Formulation of advection and mixing, J. Geophys. Res., 107, 4309, https://doi.org/10.1029/2000JD000114, 2002b. a
Mei, W. and Xie, S.-P.: Intensification of landfalling typhoons over the northwest Pacific since the late 1970s, Nat. Geosci., 9, 753–757, https://doi.org/10.1038/ngeo2792, 2016. a
Meyer, J., Rolf, C., Schiller, C., Rohs, S., Spelten, N., Afchine, A., Zöger, M., Sitnikov, N., Thornberry, T. D., Rollins, A. W., Bozóki, Z., Tátrai, D., Ebert, V., Kühnreich, B., Mackrodt, P., Möhler, O., Saathoff, H., Rosenlof, K. H., and Krämer, M.: Two decades of water vapor measurements with the FISH fluorescence hygrometer: a review, Atmos. Chem. Phys., 15, 8521–8538, https://doi.org/10.5194/acp-15-8521-2015, 2015. a
Müller, S., Hoor, P., Berkes, F., Bozem, H., Klingebiel, M., Reutter, P., Smit, H. G. J., Wendisch, M., Spichtinger, P., and Borrmann, S.: In situ detection of stratosphere–troposphere exchange of cirrus particles in the midlatitudes, Geophys. Res. Lett., 42, 949–955, https://doi.org/10.1002/2014GL062556, 2015. a
Müller, S., Hoor, P., Bozem, H., Gute, E., Vogel, B., Zahn, A., Bönisch, H., Keber, T., Krämer, M., Rolf, C., Riese, M., Schlager, H., and Engel, A.: Impact of the Asian monsoon on the extratropical lower stratosphere: trace gas observations during TACTS over Europe 2012, Atmos. Chem. Phys., 16, 10573–10589, https://doi.org/10.5194/acp-16-10573-2016, 2016. a
Murphy, D. M. and Koop, T.: Review of the vapour pressures of ice and supercooled water for atmospheric applications, Q. J. Roy. Meteor. Soc., 131, 1539–1565, 2005. a
Pan, L. L., Bowman, K. P., Shapiro, M., Randal, W. J., Gao, R. S., Campos, T., Davis, C., Schauffler, S., Ridley, B. A., Wei, J. C., and Barnet, C.: Chemical behavior of the tropopause observed during the Stratosphere-Troposphere Analyses of Regional Transport experiment, J. Geophys. Res., 112, https://doi.org/10.1029/2007JD008645, 2007. a
Pan, L. L., Atlas, E. L., Honomichl, S. B., Smith, W. P., Kinnison, D. E., Solomon, S., Santee, M. L., Saiz-Lopez, A., Laube, J. C., Wang, B., Ueyama, R., Bresch, J. F., Hornbrook, R. S., Apel, E. C., Hills, A. J., Treadaway, V., Smith, K., Schauffler, S., Donnelly, S., Hendershot, R., Lueb, R., Campos, T., Viciani, S., D'Amato, F., Bianchini, G., Barucci, M., Podolske, J. R., Iraci, L. T., Gurganus, C., Bui, P., Dean-Day, J. M., Millán, L., Ryoo, J.-M., Barletta, B., Koo, J.-H., Kim, J., Liang, Q., Randel, W. J., Thornberry, T., and Newman, P. A.: East Asian summer monsoon delivers large abundances of very short-lived organic chlorine substances to the lower stratosphere, P. Natl. Acad. Sci. USA, 121, e2318716121, https://doi.org/10.1073/pnas.2318716121, 2024. a, b, c, d
Pan, L. L., Atlas, E. L., Newman, P. A., Thornberry, T., Jucks, K. W., Toon, O. B., Randel, W. J., Liang, Q., Kinnison, D. E., Ueyama, R., Bresch, J. F., Honomichl, S. B., Smith, W. P., Hornbrook, R. S., Ziemba, L., Fujiwara, M., Apel, E. C., Barucci, M., Bianchini, G., Brown, M., Bui, T. P., Campos, T., Chin, M., D'Amato, F., Dean-Day, J., Diskin, G., Franchin, A., Gurganus, C., Iraci, L. T., Kim, J., Koo, J.-H., Lait, L. R., Lesko, K., Podolske, J. R., Rollins, A., Sakai, T., Shiraishi, K., Treadaway, V., Viciani, S., and Waxman, E.: The Asian Summer Monsoon Chemical and Climate Impact Project (ACCLIP): An Overview, J. Geophys. Res.-Atmos., 130, e2025JD044417, https://doi.org/10.1029/2025JD044417, 2025. a, b
Pandit, A. K., Vernier, J.-P., Fairlie, T. D., Bedka, K. M., Avery, M. A., Gadhavi, H., Venkat Ratnam, M., Dwivedi, S., Amar Jyothi, K., Wienhold, F. G., Vömel, H., Liu, H., Zhang, B., Kumar, B. S., Dinh, T., and Jayaraman, A.: Investigating the role of typhoon-induced waves and stratospheric hydration in the formation of tropopause cirrus clouds observed during the 2017 Asian monsoon, Atmos. Chem. Phys., 24, 14209–14238, https://doi.org/10.5194/acp-24-14209-2024, 2024. a
Park, M., Randel, W. J., Kinnison, D. E., Garcia, R. R., and Choi, W.: Seasonal variation of methane, water vapor, and nitrogen oxides near the tropopause: Satellite observations and model simulations, J. Geophys. Res., 109, D03302, https://doi.org/10.1029/2003JD003706, 2004. a
Park, M., Randel, W. J., Gettleman, A., Massie, S. T., and Jiang, J. H.: Transport above the Asian summer monsoon anticyclone inferred from Aura Microwave Limb Sounder tracers, J. Geophys. Res., 112, D16309, https://doi.org/10.1029/2006JD008294, 2007. a, b
Ploeger, F., Günther, G., Konopka, P., Fueglistaler, S., Müller, R., Hoppe, C., Kunz, A., Spang, R., Grooß, J.-U., and Riese, M.: Horizontal water vapor transport in the lower stratosphere from subtropics to high latitudes during boreal summer, J. Geophys. Res., 118, 8111–8127, https://doi.org/10.1002/jgrd.50636, 2013. a, b
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., 120, 716–733, https://doi.org/10.1002/2014JD022468, 2015. a
Ploeger, F., Konopka, P., Walker, K., and Riese, M.: Quantifying pollution transport from the Asian monsoon anticyclone into the lower stratosphere, Atmos. Chem. Phys., 17, 7055–7066, https://doi.org/10.5194/acp-17-7055-2017, 2017. a
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. a, b, c
Ploeger, F., Birner, T., Charlesworth, E., Konopka, P., and Müller, R.: Moist bias in the Pacific upper troposphere and lower stratosphere (UTLS) in climate models affects regional circulation patterns, Atmos. Chem. Phys., 24, 2033–2043, https://doi.org/10.5194/acp-24-2033-2024, 2024. a
Pommrich, R., Müller, R., Grooß, J.-U., Konopka, P., Ploeger, F., Vogel, B., Tao, M., Hoppe, C. M., Günther, G., Spelten, N., Hoffmann, L., Pumphrey, H.-C., Viciani, S., D'Amato, F., Volk, C. M., Hoor, P., Schlager, H., and Riese, M.: Tropical troposphere to stratosphere transport of carbon monoxide and long-lived trace species in the Chemical Lagrangian Model of the Stratosphere (CLaMS), Geosci. Model Dev., 7, 2895–2916, https://doi.org/10.5194/gmd-7-2895-2014, 2014. a, b, c, d
Randel, W. J. and Park, M.: Deep convective influence on the Asian summer monsoon anticyclone and associated tracer variability observed with Atmospheric Infrared Sounder (AIRS), J. Geophys. Res., 111, D12314, https://doi.org/10.1029/2005JD006490, 2006. a
Rehbein, P. J. G., Jeong, C.-H., McGuire, M. L., Yao, X., Corbin, J. C., and Evans, G. J.: Cloud and Fog Processing Enhanced Gas-to-Particle Partitioning of Trimethylamine, Environ. Sci. Technol., 45, 4346–4352, https://doi.org/10.1021/es1042113, 2011. a
Riese, M., Ploeger, F., Rap, A., Vogel, B., Konopka, P., Dameris, M., and Forster, P.: Impact of uncertainties in atmospheric mixing on simulated UTLS composition and related radiative effects, J. Geophys. Res., 117, D16305, https://doi.org/10.1029/2012JD017751, 2012. a
Riese, M., Hoor, P., Rolf, C., Kunkel, D., Vogel, B., Köllner, F., Pöhlker, M., Ploeger, F., Ungermann, J., Woiwode, W., Johansson, S., Bauer, R., Barmpounis, K., Borrmann, S., Brauner, P., Clemens, J., Dragoneas, A., Ekinci, F., Emig, N., Engel, A., Eppers, O., Fadnavis, S., Friedl-Vallon, F., Geldenhuys, M., Günther, G., Grooß, J.-U., Hegglin, M. I., Hoepfner, M., Jesswein, M., Joppe, P., Kaumanns, J., Kachula, O., Keber, T., Kretschmer, E., Lachnitt, H.-C., Lauther, V., Lloyd, P. E., Molleker, S., Müller, R., Neubert, T., Ort, L., Pöschl, U., Pöhlker, C., Rapp, M., Retzlaff, M., Rhode, S., Schneider, J., Schuck, T., Sinnhuber, B.-M., Spelten, N., Strobel, J., Tomsche, L., Turhal, K., van Luijt, R., Versick, S., Voigt, C., Volk, M., von Hobe, M., Weyland, F., Zahn, A., Ziereis, H., and Zlotos, L.: Long-range transport of polluted Asian summer monsoon air to high latitudes during the PHILEAS campaign in the boreal summer 2023, B. Am. Meteorol. Soc., https://doi.org/10.1175/BAMS-D-24-0232.1, preprint, Online Publication: 8 July 2025, 2025. a, b, c, d, e, f, g
Rolf, C., Vogel, B., Hoor, P., Afchine, A., Günther, G., Krämer, M., Müller, R., Müller, S., Spelten, N., and Riese, M.: Water vapor increase in the lower stratosphere of the Northern Hemisphere due to the Asian monsoon anticyclone observed during the TACTS/ESMVal campaigns, Atmos. Chem. Phys., 18, 2973–2983, https://doi.org/10.5194/acp-18-2973-2018, 2018. a, b, c, d, e, f
Rosenlof, K. H., Tuck, A. F., Kelly, K. K., Russell III, J. M., and McCormick, M. P.: Hemispheric asymmetries in the water vapor and inferences about transport in the lower stratosphere, J. Geophys. Res., 102, 13213–13234, https://doi.org/10.1029/97JD00873, 1997. a, b
Rotermund, M. K., Bense, V., Chipperfield, M. P., Engel, A., Grooß, J.-U., Hoor, P., Hüneke, T., Keber, T., Kluge, F., Schreiner, B., Schuck, T., Vogel, B., Zahn, A., and Pfeilsticker, K.: Organic and inorganic bromine measurements around the extratropical tropopause and lowermost stratosphere: insights into the transport pathways and total bromine, Atmos. Chem. Phys., 21, 15375–15407, https://doi.org/10.5194/acp-21-15375-2021, 2021. a
Santee, M. L., Manney, G. L., Livesey, N. J., Schwartz, M. J., Neu, J. L., and Read, W. G.: A comprehensive overview of the climatological composition of the Asian summer monsoon anticyclone based on 10 years of Aura Microwave Limb Sounder measurements, J. Geophys. Res., 122, 5491–5514, https://doi.org/10.1002/2016JD026408, 2017. a
Say, D., Ganesan, A. L., Lunt, M. F., Rigby, M., O'Doherty, S., Harth, C., Manning, A. J., Krummel, P. B., and Bauguitte, S.: Emissions of halocarbons from India inferred through atmospheric measurements, Atmos. Chem. Phys., 19, 9865–9885, https://doi.org/10.5194/acp-19-9865-2019, 2019. a
Schoeberl, M. R., Jensen, E. J., Pfister, L., Ueyama, R., Avery, M., and Dessler, A. E.: Convective Hydration of the Upper Troposphere and Lower Stratosphere, J. Geophys. Res., 123, 4583–4593, https://doi.org/10.1029/2018JD028286, 2018. a
Schuck, T. J., Brenninkmeijer, C. A. M., Baker, A. K., Slemr, F., von Velthoven, P. F. J., and Zahn, A.: Greenhouse gas relationships in the Indian summer monsoon plume measured by the CARIBIC passenger aircraft, Atmos. Chem. Phys., 10, 3965–3984, https://doi.org/10.5194/acp-10-3965-2010, 2010. a
Sinnhuber, B.-M. and Meul, S.: Simulating the impact of emissions of brominated very short lived substances on past stratospheric ozone trends, Geophys. Res. Lett., 42, 2449–2456, https://doi.org/10.1002/2014GL062975, 2015. a
Siu, L. W. and Bowman, K. P.: Unsteady Vortex Behavior in the Asian Monsoon Anticyclone, J. Atmos. Sci., 77, 4067–4088, https://doi.org/10.1175/JAS-D-19-0349.1, 2020. a
Smith, W. P., Pan, L. L., Ueyama, R., Honomichl, S., Campos, T., Viciani, S., D'Amato, F., Bianchini, G., Barruci, M., Hornbrook, R. S., Apel, E. C., Hills, A. J., Barletta, B., Atlas, E., Schauffler, S., Treadaway, V., Smith, K., Lueb, R., Hendershot, R., Donnelly, S., Rollins, A., Waxman, E., Novak, G., Huey, L. G., Tanner, D., Lee, Y. R., Bekemeier, C., and Bowman, K. P.: Transport by Asian Summer Monsoon Convection to the Upper Troposphere and Lower Stratosphere During ACCLIP (2022), J. Geophys. Res., 130, e2024JD042732, https://doi.org/10.1029/2024JD042732, 2025. a, b
Tao, M., Cai, Z., Zhu, S., Liu, Y., Feng, L., Fang, S., Yi, Y., and Bian, J.: New evidence for CH4 enhancement in the upper troposphere associated with the Asian summer monsoon, Environ. Res. Lett., 19, 034033, https://doi.org/10.1088/1748-9326/ad2738, 2024. a, b
Ueyama, R., Schoeberl, M., Jensen, E., Pfister, L., Park, M., and Ryoo, J.-M.: Convective Impact on the Global Lower Stratospheric Water Vapor Budget, J. Geophys. Res., 128, e2022JD037135, https://doi.org/10.1029/2022JD037135, 2023. a
Ungermann, J., Ern, M., Kaufmann, M., Müller, R., Spang, R., Ploeger, F., Vogel, B., and Riese, M.: Observations of PAN and its confinement in the Asian summer monsoon anticyclone in high spatial resolution, Atmos. Chem. Phys., 16, 8389–8403, https://doi.org/10.5194/acp-16-8389-2016, 2016. a
Vernier, J. P., Fairlie, T. D., Natarajan, M., Wienhold, F. G., Bian, J., Martinsson, B. G., Crumeyrolle, S., Thomason, L. W., and Bedka, K. M.: Increase in upper tropospheric and lower stratospheric aerosol levels and its potential connection with Asian pollution, J. Geophys. Res., 120, 1608–1619, https://doi.org/10.1002/2014JD022372, 2015. a
Vernier, J.-P., Fairlie, T. D., Deshler, T., Ratnam, M. V., Gadhavi, H., Kumar, B. S., Natarajan, M., Pandit, A. K., Raj, S. T. A., Kumar, A. H., Jayaraman, A., Singh, A. K., Rastogi, N., Sinha, P. R., Kumar, S., Tiwari, S., Wegner, T., Baker, N., Vignelles, D., Stenchikov, G., Shevchenko, I., Smith, J., Bedka, K., Kesarkar, A., Singh, V., Bhate, J., Ravikiran, V., Rao, M. D., Ravindrababu, S., Patel, A., Vernier, H., Wienhold, F. G., Liu, H., Knepp, T. N., Thomason, L., Crawford, J., Ziemba, L., Moore, J., Crumeyrolle, S., Williamson, M., Berthet, G., Jégou, F., and Renard, J.-B.: BATAL: The Balloon Measurement Campaigns of the Asian Tropopause Aerosol Layer, B. Am. Meteorol. Soc., 99, 955–973, https://doi.org/10.1175/BAMS-D-17-0014.1, 2018. a
Vogel, B., Pan, L. L., Konopka, P., Günther, G., Müller, R., Hall, W., Campos, T., Pollack, I., Weinheimer, A., Wei, J., Atlas, E. L., and Bowman, K. P.: Transport pathways and signatures of mixing in the extratropical tropopause region derived from Lagrangian model simulations, J. Geophys. Res., 116, D05306, https://doi.org/10.1029/2010JD014876, 2011. a
Vogel, B., Günther, G., Müller, R., Grooß, J.-U., Hoor, P., Krämer, M., Müller, S., Zahn, A., and Riese, M.: Fast transport from Southeast Asia boundary layer sources to northern Europe: rapid uplift in typhoons and eastward eddy shedding of the Asian monsoon anticyclone, Atmos. Chem. Phys., 14, 12745–12762, https://doi.org/10.5194/acp-14-12745-2014, 2014. a, b, c, d, e
Vogel, B., Günther, G., Müller, R., Grooß, J.-U., and Riese, M.: Impact of different Asian source regions on the composition of the Asian monsoon anticyclone and of the extratropical lowermost stratosphere, Atmos. Chem. Phys., 15, 13699–13716, https://doi.org/10.5194/acp-15-13699-2015, 2015. a, b, c
Vogel, B., Günther, G., Müller, R., Grooß, J.-U., Afchine, A., Bozem, H., Hoor, P., Krämer, M., Müller, S., Riese, M., Rolf, C., Spelten, N., Stiller, G. P., Ungermann, J., and Zahn, A.: Long-range transport pathways of tropospheric source gases originating in Asia into the northern lower stratosphere during the Asian monsoon season 2012, Atmos. Chem. Phys., 16, 15301–15325, https://doi.org/10.5194/acp-16-15301-2016, 2016. a, b, c, d, e, f
Vogel, B., Müller, R., Günther, G., Spang, R., Hanumanthu, S., Li, D., Riese, M., and Stiller, G. P.: Lagrangian simulations of the transport of young air masses to the top of the Asian monsoon anticyclone and into the tropical pipe, Atmos. Chem. Phys., 19, 6007–6034, https://doi.org/10.5194/acp-19-6007-2019, 2019. a, b, c, d, e
Vogel, B., Volk, C. M., Wintel, J., Lauther, V., Müller, R., Patra, P. K., Riese, M., Terao, Y., and Stroh, F.: Reconstructing high-resolution in-situ vertical carbon dioxide profiles in the sparsely monitored Asian monsoon region, Commun. Earth Environ., 4, https://doi.org/10.1038/s43247-023-00725-5, 2023. a, b, c, d, e
Vogel, B., Volk, C. M., Wintel, J., Lauther, V., Clemens, J., Grooß, J.-U., Günther, G., Hoffmann, L., Laube, J. C., Müller, R., Ploeger, F., and Stroh, F.: Evaluation of vertical transport in ERA5 and ERA-Interim reanalysis using high-altitude aircraft measurements in the Asian summer monsoon 2017, Atmos. Chem. Phys., 24, 317–343, https://doi.org/10.5194/acp-24-317-2024, 2024. a, b, c, d, e, f, g, h
Wang, B. and LinHo: Rainy Season of the Asian–Pacific Summer Monsoon, J. Climate, 15, 386–398, https://doi.org/10.1175/1520-0442(2002)015<0386:RSOTAP>2.0.CO;2, 2002. a
Wetzel, G., Friedl-Vallon, F., Glatthor, N., Grooß, J.-U., Gulde, T., Höpfner, M., Johansson, S., Khosrawi, F., Kirner, O., Kleinert, A., Kretschmer, E., Maucher, G., Nordmeyer, H., Oelhaf, H., Orphal, J., Piesch, C., Sinnhuber, B.-M., Ungermann, J., and Vogel, B.: Pollution trace gases C2H6, C2H2, HCOOH, and PAN in the North Atlantic UTLS: observations and simulations, Atmos. Chem. Phys., 21, 8213–8232, https://doi.org/10.5194/acp-21-8213-2021, 2021. a, b
Willis, M. D., Köllner, F., Burkart, J., Bozem, H., Thomas, J. L., Schneider, J., Aliabadi, A. A., Hoor, P. M., Schulz, H., Herber, A. B., Leaitch, W. R., and Abbatt, J. P. D.: Evidence for marine biogenic influence on summertime Arctic aerosol, Geophys. Res. Lett., 44, 6460–6470, https://doi.org/10.1002/2017GL073359, 2017. a
Yang, Z., Vogel, B., Plöger, F., Bai, Z., Li, D., Griessbach, S., Hoffmann, L., Wienhold, F. G., Asher, E., Baron, A. A., Smith, K. R., Thornberry, T., Bian, J., and Hegglin, M. I.: Transport of volcanic aerosol from the Raikoke eruption in 2019 through the Northern Hemisphere, Atmos. Chem. Phys., 26, 4749–4769, https://doi.org/10.5194/acp-26-4749-2026, 2026. a
Zahn, A., Weppner, J., Widmann, H., Schlote-Holubek, K., Burger, B., Kühner, T., and Franke, H.: A fast and precise chemiluminescence ozone detector for eddy flux and airborne application, Atmos. Meas. Tech., 5, 363–375, https://doi.org/10.5194/amt-5-363-2012, 2012. a
Zhu, S., Tao, M., Cai, Z., Liu, Y., Feng, L., Sangmu, P., Yu, Z., and Cao, J.: Significant response of methane in the upper troposphere to subseasonal variability in the Asian monsoon anticyclone, Atmos. Chem. Phys., 25, 9843–9857, https://doi.org/10.5194/acp-25-9843-2025, 2025. a
Zöger, M., Schiller, C., and Eicke, N.: Fast in situ hygrometers: A new family of balloonborne and airborne Lyman-α photofragment fluorescence hygrometers, J. Geophys. Res., 104, 1807–1816, 1999. a
Editorial statement
This paper reports an observational dataset for the western and the eastern flank of the Asian monsoon anticyclone (ASMA) from the PHILEAS campaign. The findings show that the chemical composition of the ASMA’s outflow is highly variable and there is an interplay between the ASMA and tropical cyclones. This study provides strong support in that the ASMA is an important pathway for transporting short-lived ozone-depleting into the stratosphere. It may help to promote further research on the influence of ASMA’s composition on ozone in the extratropical stratosphere.
This paper reports an observational dataset for the western and the eastern flank of the Asian...
Short summary
This work highlights the impact of the Asian summer monsoon on the chemical composition of the upper troposphere and lower stratosphere. Measurements of trace gases and aerosol particles uplifted by the Asian summer monsoon to higher altitudes are sparse. Here, we had the opportunity to use a whole suite of different measured trace gases and the chemical composition of aerosols, in combination with simulations, to better understand the complex transport and mixing processes in this region.
This work highlights the impact of the Asian summer monsoon on the chemical composition of the...
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