Articles | Volume 24, issue 7
https://doi.org/10.5194/acp-24-4193-2024
© Author(s) 2024. 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-24-4193-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Correction of stratospheric age of air (AoA) derived from sulfur hexafluoride (SF6) for the effect of chemical sinks
Hella Garny
CORRESPONDING AUTHOR
Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Physik der Atmosphäre, Oberpfaffenhofen, Germany
Meteorological Institute, Ludwig-Maximilians-Universität München, Munich, Germany
Roland Eichinger
Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Physik der Atmosphäre, Oberpfaffenhofen, Germany
Department of Atmospheric Physics, Faculty of Mathematics and Physics, Charles University Prague, Prague, Czech Republic
Johannes C. Laube
Institut für Energie- und Klimaforschung (IEK-7), Forschungszentrum Jülich GmbH, Jülich, Germany
Eric A. Ray
Chemical Sciences Division, Earth Systems Research Laboratory, NOAA, Boulder, Colorado, USA
Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder, Colorado, USA
Gabriele P. Stiller
Institute for Meteorology and Climate Research, Karlsruhe Institute of Technology, Karlsruhe, Germany
Harald Bönisch
Institute for Meteorology and Climate Research, Karlsruhe Institute of Technology, Karlsruhe, Germany
Laura Saunders
Department of Physics, University of Toronto, Toronto, Ontario, Canada
Marianna Linz
Department of Earth and Planetary Sciences, School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts, USA
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Atmos. Chem. Phys., 24, 12425–12445, https://doi.org/10.5194/acp-24-12425-2024, https://doi.org/10.5194/acp-24-12425-2024, 2024
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In this study we describe new techniques to derive age of air from multiple simultaneous measurements of long-lived trace gases in order to improve the fidelity of the age-of-air estimates and to be able to compare age of air from measurements taken from different instruments, platforms and decades. This technique also allows new transport information to be obtained from the measurements such as the primary source latitude that can also be compared to models.
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
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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.
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Atmos. Chem. Phys., 24, 1389–1413, https://doi.org/10.5194/acp-24-1389-2024, https://doi.org/10.5194/acp-24-1389-2024, 2024
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During winter, a brief but abrupt reversal of the mean stratospheric westerly flow (~30 km high) around the Arctic occurs ~6 times a decade. Using a chemistry–climate model, about half of these events are shown to induce large anomalies in Arctic ozone (>25 %) and water vapour (>±25 %) around ~8–12 km altitude for up to 2–3 months, important for weather forecasting. We also calculate a doubling to trebling of the risk in breaches of mid-latitude surface air quality (ozone) standards (~60 ppbv).
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Geosci. Model Dev., 16, 5561–5583, https://doi.org/10.5194/gmd-16-5561-2023, https://doi.org/10.5194/gmd-16-5561-2023, 2023
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The columnar approach of gravity wave (GW) schemes results in dynamical model biases, but parallel decomposition makes horizontal GW propagation computationally unfeasible. In the global model EMAC, we approximate it by GW redistribution at one altitude using tailor-made redistribution maps generated with a ray tracer. More spread-out GW drag helps reconcile the model with observations and close the 60°S GW gap. Polar vortex dynamics are improved, enhancing climate model credibility.
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.
Matthias Nützel, Sabine Brinkop, Martin Dameris, Hella Garny, Patrick Jöckel, Laura L. Pan, and Mijeong Park
Atmos. Chem. Phys., 22, 15659–15683, https://doi.org/10.5194/acp-22-15659-2022, https://doi.org/10.5194/acp-22-15659-2022, 2022
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During the Asian summer monsoon season, a large high-pressure system is present at levels close to the tropopause above Asia. We analyse how air masses are transported from surface levels to this high-pressure system, which shows distinct features from the surrounding air masses. To this end, we employ multiannual data from two complementary models that allow us to analyse the climatology as well as the interannual and intraseasonal variability of these transport pathways.
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.
Sheena Loeffel, Roland Eichinger, Hella Garny, Thomas Reddmann, Frauke Fritsch, Stefan Versick, Gabriele Stiller, and Florian Haenel
Atmos. Chem. Phys., 22, 1175–1193, https://doi.org/10.5194/acp-22-1175-2022, https://doi.org/10.5194/acp-22-1175-2022, 2022
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SF6-derived trends of stratospheric AoA from observations and model simulations disagree in sign. SF6 experiences chemical degradation, which we explicitly integrate in a global climate model. In our simulations, the AoA trend changes sign when SF6 sinks are considered; thus, the process has the potential to reconcile simulated with observed AoA trends. We show that the positive AoA trend is due to the SF6 sinks themselves and provide a first approach for a correction to account for SF6 loss.
Marta Abalos, Natalia Calvo, Samuel Benito-Barca, Hella Garny, Steven C. Hardiman, Pu Lin, Martin B. Andrews, Neal Butchart, Rolando Garcia, Clara Orbe, David Saint-Martin, Shingo Watanabe, and Kohei Yoshida
Atmos. Chem. Phys., 21, 13571–13591, https://doi.org/10.5194/acp-21-13571-2021, https://doi.org/10.5194/acp-21-13571-2021, 2021
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The stratospheric Brewer–Dobson circulation (BDC), responsible for transporting mass, tracers and heat globally in the stratosphere, is evaluated in a set of state-of-the-art climate models. The acceleration of the BDC in response to increasing greenhouse gases is most robust in the lower stratosphere. At higher levels, the well-known inconsistency between model and observational BDC trends can be partly reconciled by accounting for limited sampling and large uncertainties in the observations.
Simone Dietmüller, Hella Garny, Roland Eichinger, and William T. Ball
Atmos. Chem. Phys., 21, 6811–6837, https://doi.org/10.5194/acp-21-6811-2021, https://doi.org/10.5194/acp-21-6811-2021, 2021
Hella Garny, Roland Walz, Matthias Nützel, and Thomas Birner
Geosci. Model Dev., 13, 5229–5257, https://doi.org/10.5194/gmd-13-5229-2020, https://doi.org/10.5194/gmd-13-5229-2020, 2020
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Numerical models of Earth's climate system have been gaining more and more complexity over the last decades. Therefore, it is important to establish simplified models to improve process understanding. In our study, we present and document the development of a new simplified model setup within the framework of a complex climate model system that uses the same routines to calculate atmospheric dynamics as the complex model but is simplified in the representation of clouds and radiation.
Frauke Fritsch, Hella Garny, Andreas Engel, Harald Bönisch, and Roland Eichinger
Atmos. Chem. Phys., 20, 8709–8725, https://doi.org/10.5194/acp-20-8709-2020, https://doi.org/10.5194/acp-20-8709-2020, 2020
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We test two methods to derive age of air as a diagnostic of the Brewer–Dobson circulation from non-linear increasing trace gases such as SF6 using a chemistry-climate model and observations. Both the model and the observations show systematic variation of the age of air trend dependent on the chosen assumptions that are required when deriving age of air from measurements. This provides insight into the differences in age of air trends of observations and models.
Andreas Chrysanthou, Amanda C. Maycock, Martyn P. Chipperfield, Sandip Dhomse, Hella Garny, Douglas Kinnison, Hideharu Akiyoshi, Makoto Deushi, Rolando R. Garcia, Patrick Jöckel, Oliver Kirner, Giovanni Pitari, David A. Plummer, Laura Revell, Eugene Rozanov, Andrea Stenke, Taichu Y. Tanaka, Daniele Visioni, and Yousuke Yamashita
Atmos. Chem. Phys., 19, 11559–11586, https://doi.org/10.5194/acp-19-11559-2019, https://doi.org/10.5194/acp-19-11559-2019, 2019
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We perform the first multi-model comparison of the impact of nudged meteorology on the stratospheric residual circulation (RC) in chemistry–climate models. Nudging meteorology does not constrain the mean strength of RC compared to free-running simulations, and despite the lack of agreement in the mean circulation, nudging tightly constrains the inter-annual variability in the tropical upward mass flux in the lower stratosphere. In summary, nudging strongly affects the representation of RC.
Matthias Nützel, Aurélien Podglajen, Hella Garny, and Felix Ploeger
Atmos. Chem. Phys., 19, 8947–8966, https://doi.org/10.5194/acp-19-8947-2019, https://doi.org/10.5194/acp-19-8947-2019, 2019
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We investigate the transport pathways of water vapour from the upper troposphere in the Asian monsoon region to the stratosphere. In the employed chemistry-transport model we use a tagging method, such that the impact of different source regions on the stratospheric water vapour budget can be quantified. A key finding is that the Asian monsoon (compared to other source regions) is very efficient in transporting air masses and water vapour to the tropical and extratropical stratosphere.
Petr Šácha, Roland Eichinger, Hella Garny, Petr Pišoft, Simone Dietmüller, Laura de la Torre, David A. Plummer, Patrick Jöckel, Olaf Morgenstern, Guang Zeng, Neal Butchart, and Juan A. Añel
Atmos. Chem. Phys., 19, 7627–7647, https://doi.org/10.5194/acp-19-7627-2019, https://doi.org/10.5194/acp-19-7627-2019, 2019
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Climate models robustly project a Brewer–Dobson circulation (BDC) acceleration in the course of climate change. Analyzing mean age of stratospheric air (AoA) from a subset of climate projection simulations, we find a remarkable agreement in simulating the largest AoA trends in the extratropical stratosphere. This is shown to be related with the upward shift of the circulation, resulting in a so-called stratospheric shrinkage, which could be one of the so-far-omitted BDC acceleration drivers.
Marius Hauck, Frauke Fritsch, Hella Garny, and Andreas Engel
Atmos. Chem. Phys., 19, 5269–5291, https://doi.org/10.5194/acp-19-5269-2019, https://doi.org/10.5194/acp-19-5269-2019, 2019
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The paper presents a modified method to invert mixing ratios of chemically active tracers into stratospheric age spectra. It features an imposed seasonal cycle to include transport seasonality into the spectra. An idealized set of tracers from a model is used as proof of concept and results are in good agreement with the model reference, except for the lowermost stratosphere. Applicability is studied with focus on number of tracers and error tolerance, providing a starting point for future work.
Roland Eichinger, Simone Dietmüller, Hella Garny, Petr Šácha, Thomas Birner, Harald Bönisch, Giovanni Pitari, Daniele Visioni, Andrea Stenke, Eugene Rozanov, Laura Revell, David A. Plummer, Patrick Jöckel, Luke Oman, Makoto Deushi, Douglas E. Kinnison, Rolando Garcia, Olaf Morgenstern, Guang Zeng, Kane Adam Stone, and Robyn Schofield
Atmos. Chem. Phys., 19, 921–940, https://doi.org/10.5194/acp-19-921-2019, https://doi.org/10.5194/acp-19-921-2019, 2019
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To shed more light upon the changes in stratospheric circulation in the 21st century, climate projection simulations of 10 state-of-the-art global climate models, spanning from 1960 to 2100, are analyzed. The study shows that in addition to changes in transport, mixing also plays an important role in stratospheric circulation and that the properties of mixing vary over time. Furthermore, the influence of mixing is quantified and a dynamical framework is provided to understand the changes.
Simone Dietmüller, Roland Eichinger, Hella Garny, Thomas Birner, Harald Boenisch, Giovanni Pitari, Eva Mancini, Daniele Visioni, Andrea Stenke, Laura Revell, Eugene Rozanov, David A. Plummer, John Scinocca, Patrick Jöckel, Luke Oman, Makoto Deushi, Shibata Kiyotaka, Douglas E. Kinnison, Rolando Garcia, Olaf Morgenstern, Guang Zeng, Kane Adam Stone, and Robyn Schofield
Atmos. Chem. Phys., 18, 6699–6720, https://doi.org/10.5194/acp-18-6699-2018, https://doi.org/10.5194/acp-18-6699-2018, 2018
Stefan Lossow, Hella Garny, and Patrick Jöckel
Atmos. Chem. Phys., 17, 11521–11539, https://doi.org/10.5194/acp-17-11521-2017, https://doi.org/10.5194/acp-17-11521-2017, 2017
Simone Dietmüller, Hella Garny, Felix Plöger, Patrick Jöckel, and Duy Cai
Atmos. Chem. Phys., 17, 7703–7719, https://doi.org/10.5194/acp-17-7703-2017, https://doi.org/10.5194/acp-17-7703-2017, 2017
Matthias Nützel, Martin Dameris, and Hella Garny
Atmos. Chem. Phys., 16, 14755–14774, https://doi.org/10.5194/acp-16-14755-2016, https://doi.org/10.5194/acp-16-14755-2016, 2016
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Using seven reanalyses, we study the movement and drivers of the upper tropospheric–lower stratospheric anticyclone (AC) that forms during the Asian summer monsoon and is debated to be an important pathway for air masses to the stratosphere. We find that the distribution of the AC's centre position, and especially the so-called bimodality, largely depends on the reanalysis. Furthermore, we can connect shifts of the AC to precipitation and convection anomalies over India and the western Pacific.
Duy Cai, Martin Dameris, Hella Garny, Felix Bunzel, Patrick Jöckel, and Phoebe Graf
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2016-870, https://doi.org/10.5194/acp-2016-870, 2016
Revised manuscript not accepted
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Reliable information on weather and climate are of increasing interest for economy, politics and society.
In particular decadal timescales become more and more important. This study focuses on stratospheric processes relevant for the dynamical variability on intra decadal timescale. We apply a so called power spectra analysis. With this method and further analyses we could determine a minimum vertical resolution for numerical models, which is required to capture these processes.
Sabine Brinkop, Martin Dameris, Patrick Jöckel, Hella Garny, Stefan Lossow, and Gabriele Stiller
Atmos. Chem. Phys., 16, 8125–8140, https://doi.org/10.5194/acp-16-8125-2016, https://doi.org/10.5194/acp-16-8125-2016, 2016
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This study investigates the water vapour decline in the stratosphere beginning in the year 2000 and other similarly strong stratospheric water vapour reductions. The driving forces are tropical sea surface temperature (SST) changes due to coincidence with a preceding ENSO event and supported by the west to east change of the QBO.
There are indications that both SSTs and the specific dynamical state of the atmosphere contribute to the long period of low water vapour values from 2001 to 2006.
Patrick Jöckel, Holger Tost, Andrea Pozzer, Markus Kunze, Oliver Kirner, Carl A. M. Brenninkmeijer, Sabine Brinkop, Duy S. Cai, Christoph Dyroff, Johannes Eckstein, Franziska Frank, Hella Garny, Klaus-Dirk Gottschaldt, Phoebe Graf, Volker Grewe, Astrid Kerkweg, Bastian Kern, Sigrun Matthes, Mariano Mertens, Stefanie Meul, Marco Neumaier, Matthias Nützel, Sophie Oberländer-Hayn, Roland Ruhnke, Theresa Runde, Rolf Sander, Dieter Scharffe, and Andreas Zahn
Geosci. Model Dev., 9, 1153–1200, https://doi.org/10.5194/gmd-9-1153-2016, https://doi.org/10.5194/gmd-9-1153-2016, 2016
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With an advanced numerical global chemistry climate model (CCM) we performed several detailed
combined hind-cast and projection simulations of the period 1950 to 2100 to assess the
past, present, and potential future dynamical and chemical state of the Earth atmosphere.
The manuscript documents the model and the various applied model set-ups and provides
a first evaluation of the simulation results from a global perspective as a quality check of the data.
Hella Garny and William J. Randel
Atmos. Chem. Phys., 16, 2703–2718, https://doi.org/10.5194/acp-16-2703-2016, https://doi.org/10.5194/acp-16-2703-2016, 2016
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We investigate the fate of air that originates in the monsoon region in the upper troposphere, where it was transported to by convection. We find that almost half of the air parcels released in the monsoon region in the upper troposphere reach the stratosphere within 60 days, and most ascend to the tropical lower stratosphere. This suggests that trace gases, including pollutants, that are transported into the stratosphere via the Asian monsoon are in a position to enter the deep stratosphere.
L. E. Revell, F. Tummon, A. Stenke, T. Sukhodolov, A. Coulon, E. Rozanov, H. Garny, V. Grewe, and T. Peter
Atmos. Chem. Phys., 15, 5887–5902, https://doi.org/10.5194/acp-15-5887-2015, https://doi.org/10.5194/acp-15-5887-2015, 2015
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We have examined the effects of ozone precursor emissions and climate change on the tropospheric ozone budget. Under RCP 6.0, ozone in the future is governed primarily by changes in nitrogen oxides (NOx). Methane is also important, and induces an increase in tropospheric ozone that is approximately one-third of that caused by NOx. This study highlights the critical role that emission policies globally have to play in determining tropospheric ozone evolution through the 21st century.
S. Meul, U. Langematz, S. Oberländer, H. Garny, and P. Jöckel
Atmos. Chem. Phys., 14, 2959–2971, https://doi.org/10.5194/acp-14-2959-2014, https://doi.org/10.5194/acp-14-2959-2014, 2014
V. Grewe, C. Frömming, S. Matthes, S. Brinkop, M. Ponater, S. Dietmüller, P. Jöckel, H. Garny, E. Tsati, K. Dahlmann, O. A. Søvde, J. Fuglestvedt, T. K. Berntsen, K. P. Shine, E. A. Irvine, T. Champougny, and P. Hullah
Geosci. Model Dev., 7, 175–201, https://doi.org/10.5194/gmd-7-175-2014, https://doi.org/10.5194/gmd-7-175-2014, 2014
H. Garny, G. E. Bodeker, D. Smale, M. Dameris, and V. Grewe
Atmos. Chem. Phys., 13, 7279–7300, https://doi.org/10.5194/acp-13-7279-2013, https://doi.org/10.5194/acp-13-7279-2013, 2013
Eric A. Ray, Fred L. Moore, Hella Garny, Eric J. Hintsa, Bradley D. Hall, Geoff S. Dutton, David Nance, James W. Elkins, Steven C. Wofsy, Jasna Pittman, Bruce Daube, Bianca C. Baier, Jianghanyang Li, and Colm Sweeney
Atmos. Chem. Phys., 24, 12425–12445, https://doi.org/10.5194/acp-24-12425-2024, https://doi.org/10.5194/acp-24-12425-2024, 2024
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In this study we describe new techniques to derive age of air from multiple simultaneous measurements of long-lived trace gases in order to improve the fidelity of the age-of-air estimates and to be able to compare age of air from measurements taken from different instruments, platforms and decades. This technique also allows new transport information to be obtained from the measurements such as the primary source latitude that can also be compared to models.
Tanja J. Schuck, Johannes Degen, Timo Keber, Katharina Meixner, Thomas Wagenhäuser, Mélanie Ghysels, Georges Durry, Nadir Amarouche, Alessandro Zanchetta, Steven van Heuven, Huilin Chen, Johannes C. Laube, Sophie Baartman, Carina van der Veen, Maria Elena Popa, and Andreas Engel
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Florian Voet, Felix Plöger, Johannes Laube, Peter Preusse, Paul Konopka, Jens-Uwe Grooß, Jörn Ungermann, Björn-Martin Sinnhuber, Michael Hoepfner, Bernd Funke, Gerald Wetzel, Sören Johansson, Gabriele Stiller, Eric Ray, and Michaela Imelda Hegglin
EGUsphere, https://doi.org/10.5194/egusphere-2024-2624, https://doi.org/10.5194/egusphere-2024-2624, 2024
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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.
Louis Rivoire, Marianna Linz, Jessica L. Neu, Pu Lin, and Michelle L. Santee
EGUsphere, https://doi.org/10.5194/egusphere-2024-2627, https://doi.org/10.5194/egusphere-2024-2627, 2024
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The recovery of the ozone hole since the 1987 Montreal Protocol has been observed in some regions, but has yet to be seen globally. We ask: how long will it take to witness a global recovery? Using a technique akin to flying a virtual satellite in a climate model, we find that the degree of confidence we place in the answer to this question is dramatically affected by errors in satellite observations.
Patrick Konjari, Christian Rolf, Michaela Imelda Hegglin, Susanne Rohs, Yun Li, Andreas Zahn, Harald Bönisch, Martina Krämer, and Andreas Petzold
EGUsphere, https://doi.org/10.5194/egusphere-2024-2360, https://doi.org/10.5194/egusphere-2024-2360, 2024
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This study introduces a new method to deriving 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 vapor 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
EGUsphere, https://doi.org/10.5194/egusphere-2024-2117, https://doi.org/10.5194/egusphere-2024-2117, 2024
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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.
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.
Ales Kuchar, Maurice Öhlert, Roland Eichinger, and Christoph Jacobi
Weather Clim. Dynam., 5, 895–912, https://doi.org/10.5194/wcd-5-895-2024, https://doi.org/10.5194/wcd-5-895-2024, 2024
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Exploring the polar vortex's impact on climate, the study evaluates model simulations against the ERA5 reanalysis data. Revelations about model discrepancies in simulating disruptive stratospheric warmings and vortex behavior highlight the need for refined model simulations of past climate. By enhancing our understanding of these dynamics, the research contributes to more reliable climate projections of the polar vortex with the impact on surface climate.
Norbert Glatthor, Gabriele P. Stiller, Thomas von Clarmann, Bernd Funke, Sylvia Kellmann, and Andrea Linden
EGUsphere, https://doi.org/10.5194/egusphere-2024-1793, https://doi.org/10.5194/egusphere-2024-1793, 2024
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We present global upper tropospheric distributions of the pollutants HCN, CO, C2H2, C2H6, PAN and HCOOH, observed by MIPAS/Envisat between 2002 and 2012. This common view allows conclusions on the sources of the different pollutants, like, e.g., biomass burning, anthropogenic sources or biogenic release. For this purpose we compare their VMR distributions and additionally perform global correlation and regression analyses.
Karen De Los Ríos, Paulina Ordoñez, Gabriele P. Stiller, Piera Raspollini, Marco Gai, Kaley A. Walker, Cristina Peña-Ortiz, and Luis Acosta
Atmos. Meas. Tech., 17, 3401–3418, https://doi.org/10.5194/amt-17-3401-2024, https://doi.org/10.5194/amt-17-3401-2024, 2024
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This study examines newer versions of H2O and HDO retrievals from Envisat/MIPAS and SCISAT/ACE-FTS. Results reveal a better agreement in stratospheric H2O profiles than in HDO profiles. The H2O tape recorder signal is consistent across databases, but δD tape recorder composites show differences that impact the interpretation of water vapour transport. These findings enhance the need for intercomparisons to refine our insights.
Gregory P. Schill, Karl D. Froyd, Daniel M. Murphy, Christina J. Williamson, Charles Brock, Tomás Sherwen, Mat J. Evans, Eric A. Ray, Eric C. Apel, Rebecca S. Hornbrook, Alan J. Hills, Jeff Peischl, Tomas B. Ryerson, Chelsea R. Thompson, Ilann Bourgeois, Donald R. Blake, Joshua P. DiGangi, and Glenn S. Diskin
EGUsphere, https://doi.org/10.5194/egusphere-2024-1399, https://doi.org/10.5194/egusphere-2024-1399, 2024
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Using single-particle mass spectrometry, we show that trace concentrations of bromine and iodine are ubiquitous in remote tropospheric aerosol, and suggest that aerosols are an important part of the global reactive iodine budget. Comparisons to a global climate model with detailed iodine chemistry are favorable in the background atmosphere; however, the model cannot replicate our measurements near the ocean surface, in biomass burning plumes, and in the stratosphere.
Jezabel Curbelo and Marianna Linz
EGUsphere, https://doi.org/10.5194/egusphere-2024-1348, https://doi.org/10.5194/egusphere-2024-1348, 2024
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Studying stratospheric mixing is crucial for understanding atmospheric dynamics and chemical transport. We propose a new Lagrangian metric based on the density of transport barriers, attracting/repelling coherent structures, to analyze mixing in the Whole Atmosphere Community Climate Model. Our metric is a promising tool for stratospheric analysis, consistent with commonly used metrics to quantify mixing while also providing the advantage of reflecting Lagrangian transport in physical latitude.
Norbert Glatthor, Thomas von Clarmann, Bernd Funke, Maya García-Comas, Udo Grabowski, Michael Höpfner, Sylvia Kellmann, Michael Kiefer, Alexandra Laeng, Andrea Linden, Manuel López-Puertas, and Gabriele P. Stiller
Atmos. Meas. Tech., 17, 2849–2871, https://doi.org/10.5194/amt-17-2849-2024, https://doi.org/10.5194/amt-17-2849-2024, 2024
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We present global atmospheric methane (CH4) and nitrous oxide (N2O) distributions retrieved from measurements of the MIPAS instrument on board the Environmental Satellite (Envisat) during 2002 to 2012. Monitoring of these gases is of scientific interest because both of them are strong greenhouse gases. We analyze the latest, improved version of calibrated MIPAS measurements. Further, we apply a new retrieval scheme leading to an improved CH4 and N2O data product .
Felicia Kolonjari, Patrick E. Sheese, Kaley A. Walker, Chris D. Boone, David A. Plummer, Andreas Engel, Stephen A. Montzka, David E. Oram, Tanja Schuck, Gabriele P. Stiller, and Geoffrey C. Toon
Atmos. Meas. Tech., 17, 2429–2449, https://doi.org/10.5194/amt-17-2429-2024, https://doi.org/10.5194/amt-17-2429-2024, 2024
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The Canadian Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE-FTS) satellite instrument is currently providing the only vertically resolved chlorodifluoromethane (HCFC-22) measurements from space. This study assesses the most current ACE-FTS HCFC-22 data product in the upper troposphere and lower stratosphere, as well as modelled HCFC-22 from a 39-year run of the Canadian Middle Atmosphere Model (CMAM39) in the same region.
Gabriele P. Stiller, Thomas von Clarmann, Norbert Glatthor, Udo Grabowski, Sylvia Kellmann, Michael Kiefer, Alexandra Laeng, Andrea Linden, Bernd Funke, Maya García-Comas, and Manuel López-Puertas
Atmos. Meas. Tech., 17, 1759–1789, https://doi.org/10.5194/amt-17-1759-2024, https://doi.org/10.5194/amt-17-1759-2024, 2024
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CFC-11, CFC-12, and HCFC-22 contribute to the depletion of ozone and are potent greenhouse gases. They have been banned by the Montreal protocol. With MIPAS on Envisat the atmospheric composition could be observed between 2002 and 2012. We present here the retrieval of their atmospheric distributions for the final data version 8. We characterise the derived data by their error budget and their spatial resolution. An additional representation for direct comparison to models is also provided.
Ryan S. Williams, Michaela I. Hegglin, Patrick Jöckel, Hella Garny, and Keith P. Shine
Atmos. Chem. Phys., 24, 1389–1413, https://doi.org/10.5194/acp-24-1389-2024, https://doi.org/10.5194/acp-24-1389-2024, 2024
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During winter, a brief but abrupt reversal of the mean stratospheric westerly flow (~30 km high) around the Arctic occurs ~6 times a decade. Using a chemistry–climate model, about half of these events are shown to induce large anomalies in Arctic ozone (>25 %) and water vapour (>±25 %) around ~8–12 km altitude for up to 2–3 months, important for weather forecasting. We also calculate a doubling to trebling of the risk in breaches of mid-latitude surface air quality (ozone) standards (~60 ppbv).
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.
Manuel López-Puertas, Maya García-Comas, Bernd Funke, Thomas von Clarmann, Norbert Glatthor, Udo Grabowski, Sylvia Kellmann, Michael Kiefer, Alexandra Laeng, Andrea Linden, and Gabriele P. Stiller
Atmos. Meas. Tech., 16, 5609–5645, https://doi.org/10.5194/amt-16-5609-2023, https://doi.org/10.5194/amt-16-5609-2023, 2023
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This paper describes a new version (V8) of ozone data from MIPAS middle-atmosphere spectra. The dataset comprises high-quality ozone profiles from 20 to 100 km, with pole-to-pole latitude coverage for the day- and nighttime, spanning 2005 until 2012. An exhaustive treatment of errors has been performed. Compared to other satellite instruments, MIPAS ozone shows a positive bias of 5 %–8 % below 70 km. In the upper mesosphere, this new version agrees much better than previous ones (within 10 %).
Maya García-Comas, Bernd Funke, Manuel López-Puertas, Norbert Glatthor, Udo Grabowski, Sylvia Kellmann, Michael Kiefer, Andrea Linden, Belén Martínez-Mondéjar, Gabriele P. Stiller, and Thomas von Clarmann
Atmos. Meas. Tech., 16, 5357–5386, https://doi.org/10.5194/amt-16-5357-2023, https://doi.org/10.5194/amt-16-5357-2023, 2023
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We have released version 8 of MIPAS IMK–IAA temperatures and pointing information retrieved from MIPAS Middle and Upper Atmosphere mode version 8.03 calibrated spectra, covering 20–115 km altitude. We considered non-local thermodynamic equilibrium emission explicitly for each limb scan, essential to retrieve accurate temperatures above the mid-mesosphere. Comparisons of this temperature dataset with SABER measurements show excellent agreement, improving those of previous MIPAS versions.
Monali Borthakur, Miriam Sinnhuber, Alexandra Laeng, Thomas Reddmann, Peter Braesicke, Gabriele Stiller, Thomas von Clarmann, Bernd Funke, Ilya Usoskin, Jan Maik Wissing, and Olesya Yakovchuk
Atmos. Chem. Phys., 23, 12985–13013, https://doi.org/10.5194/acp-23-12985-2023, https://doi.org/10.5194/acp-23-12985-2023, 2023
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Reduced ozone levels resulting from ozone depletion mean more exposure to UV radiation, which has various effects on human health. We analysed solar events to see what influence it has on the chemistry of Earth's atmosphere and how this atmospheric chemistry change can affect the ozone. To do this, we used an atmospheric model considering only chemistry and compared it with satellite data. The focus was mainly on the contribution of chlorine, and we found about 10 %–20 % ozone loss due to that.
Michael Kiefer, Dale F. Hurst, Gabriele P. Stiller, Stefan Lossow, Holger Vömel, John Anderson, Faiza Azam, Jean-Loup Bertaux, Laurent Blanot, Klaus Bramstedt, John P. Burrows, Robert Damadeo, Bianca Maria Dinelli, Patrick Eriksson, Maya García-Comas, John C. Gille, Mark Hervig, Yasuko Kasai, Farahnaz Khosrawi, Donal Murtagh, Gerald E. Nedoluha, Stefan Noël, Piera Raspollini, William G. Read, Karen H. Rosenlof, Alexei Rozanov, Christopher E. Sioris, Takafumi Sugita, Thomas von Clarmann, Kaley A. Walker, and Katja Weigel
Atmos. Meas. Tech., 16, 4589–4642, https://doi.org/10.5194/amt-16-4589-2023, https://doi.org/10.5194/amt-16-4589-2023, 2023
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We quantify biases and drifts (and their uncertainties) between the stratospheric water vapor measurement records of 15 satellite-based instruments (SATs, with 31 different retrievals) and balloon-borne frost point hygrometers (FPs) launched at 27 globally distributed stations. These comparisons of measurements during the period 2000–2016 are made using robust, consistent statistical methods. With some exceptions, the biases and drifts determined for most SAT–FP pairs are < 10 % and < 1 % yr−1.
Roland Eichinger, Sebastian Rhode, Hella Garny, Peter Preusse, Petr Pisoft, Aleš Kuchař, Patrick Jöckel, Astrid Kerkweg, and Bastian Kern
Geosci. Model Dev., 16, 5561–5583, https://doi.org/10.5194/gmd-16-5561-2023, https://doi.org/10.5194/gmd-16-5561-2023, 2023
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The columnar approach of gravity wave (GW) schemes results in dynamical model biases, but parallel decomposition makes horizontal GW propagation computationally unfeasible. In the global model EMAC, we approximate it by GW redistribution at one altitude using tailor-made redistribution maps generated with a ray tracer. More spread-out GW drag helps reconcile the model with observations and close the 60°S GW gap. Polar vortex dynamics are improved, enhancing climate model credibility.
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.
Stephen Bourguet and Marianna Linz
Atmos. Chem. Phys., 23, 7447–7460, https://doi.org/10.5194/acp-23-7447-2023, https://doi.org/10.5194/acp-23-7447-2023, 2023
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Here, we show how projected changes to tropical circulation will impact the water vapor concentration in the lower stratosphere, which has implications for surface climate and stratospheric chemistry. In our transport scenarios with slower east–west winds, air parcels ascending into the stratosphere do not experience the same cold temperatures that they would today. This effect could act in concert with previously modeled changes to stratospheric water vapor to amplify surface warming.
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.
Bernd Funke, Maya García-Comas, Norbert Glatthor, Udo Grabowski, Sylvia Kellmann, Michael Kiefer, Andrea Linden, Manuel López-Puertas, Gabriele P. Stiller, and Thomas von Clarmann
Atmos. Meas. Tech., 16, 2167–2196, https://doi.org/10.5194/amt-16-2167-2023, https://doi.org/10.5194/amt-16-2167-2023, 2023
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New global nitric oxide (NO) volume-mixing-ratio and lower-thermospheric temperature data products, retrieved from Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) spectra with the IMK-IAA MIPAS data processor, have been released. The dataset covers the entire Envisat mission lifetime and includes retrieval results from all MIPAS observation modes. The data are based on ESA version 8 calibration and were processed using an improved retrieval approach.
Michael Kiefer, Thomas von Clarmann, Bernd Funke, Maya García-Comas, Norbert Glatthor, Udo Grabowski, Michael Höpfner, Sylvia Kellmann, Alexandra Laeng, Andrea Linden, Manuel López-Puertas, and Gabriele P. Stiller
Atmos. Meas. Tech., 16, 1443–1460, https://doi.org/10.5194/amt-16-1443-2023, https://doi.org/10.5194/amt-16-1443-2023, 2023
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A new ozone data set, derived from radiation measurements of the space-borne instrument MIPAS, is presented. It consists of more than 2 million single ozone profiles from 2002–2012, covering virtually all latitudes and altitudes between 5 and 70 km. Progress in data calibration and processing methods allowed for significant improvement of the data quality, compared to previous data versions. Hence, the data set will help to better understand e.g. the time evolution of ozone in the stratosphere.
Sean M. Davis, Nicholas Davis, Robert W. Portmann, Eric Ray, and Karen Rosenlof
Atmos. Chem. Phys., 23, 3347–3361, https://doi.org/10.5194/acp-23-3347-2023, https://doi.org/10.5194/acp-23-3347-2023, 2023
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Ozone in the lower part of the stratosphere has not increased and has perhaps even continued to decline in recent decades. This study demonstrates that the amount of ozone in this region is highly sensitive to the amount of air upwelling into the stratosphere in the tropics and that simulations from a climate model nudged to historical meteorological fields often fail to accurately capture the variations in tropical upwelling that control short-term trends in lower-stratospheric ozone.
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.
Matthias Nützel, Sabine Brinkop, Martin Dameris, Hella Garny, Patrick Jöckel, Laura L. Pan, and Mijeong Park
Atmos. Chem. Phys., 22, 15659–15683, https://doi.org/10.5194/acp-22-15659-2022, https://doi.org/10.5194/acp-22-15659-2022, 2022
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During the Asian summer monsoon season, a large high-pressure system is present at levels close to the tropopause above Asia. We analyse how air masses are transported from surface levels to this high-pressure system, which shows distinct features from the surrounding air masses. To this end, we employ multiannual data from two complementary models that allow us to analyse the climatology as well as the interannual and intraseasonal variability of these transport pathways.
Thomas von Clarmann, Norbert Glatthor, Udo Grabowski, Bernd Funke, Michael Kiefer, Anne Kleinert, Gabriele P. Stiller, Andrea Linden, and Sylvia Kellmann
Atmos. Meas. Tech., 15, 6991–7018, https://doi.org/10.5194/amt-15-6991-2022, https://doi.org/10.5194/amt-15-6991-2022, 2022
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Errors of profiles of temperature and mixing ratios retrieved from spectra recorded with the Michelson Interferometer for Passive Atmospheric Sounding are estimated. All known and quantified sources of uncertainty are considered. Some ongoing uncertaities contribute to both the random and to the systematic errors. In some cases, one source of uncertainty propagates onto the error budget via multiple pathways. Problems arise when the correlations of errors to be propagated are unknown.
Stephen Bourguet and Marianna Linz
Atmos. Chem. Phys., 22, 13325–13339, https://doi.org/10.5194/acp-22-13325-2022, https://doi.org/10.5194/acp-22-13325-2022, 2022
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Here, we tested the impact of spatial and temporal resolution on Lagrangian trajectory studies in a key region of interest for climate feedbacks and stratospheric chemistry. Our analysis shows that new higher-resolution input data provide an opportunity for a better understanding of physical processes that control how air moves from the troposphere to the stratosphere. Future studies of how these processes will change in a warming climate will benefit from these results.
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.
Ales Kuchar, Petr Sacha, Roland Eichinger, Christoph Jacobi, Petr Pisoft, and Harald Rieder
EGUsphere, https://doi.org/10.5194/egusphere-2022-474, https://doi.org/10.5194/egusphere-2022-474, 2022
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We focus on the impact of small-scale orographic gravity waves (OGWs) above the Himalayas. The interaction of GWs with the large-scale circulation in the stratosphere is not still well understood and can have implications on climate projections. We use a chemistry-climate model to show that these strong OGW events are associated with anomalously increased upward planetary-scale waves and in turn affect the circumpolar circulation and have the potential to alter ozone variability as well.
William G. Read, Gabriele Stiller, Stefan Lossow, Michael Kiefer, Farahnaz Khosrawi, Dale Hurst, Holger Vömel, Karen Rosenlof, Bianca M. Dinelli, Piera Raspollini, Gerald E. Nedoluha, John C. Gille, Yasuko Kasai, Patrick Eriksson, Christopher E. Sioris, Kaley A. Walker, Katja Weigel, John P. Burrows, and Alexei Rozanov
Atmos. Meas. Tech., 15, 3377–3400, https://doi.org/10.5194/amt-15-3377-2022, https://doi.org/10.5194/amt-15-3377-2022, 2022
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This paper attempts to provide an assessment of the accuracy of 21 satellite-based instruments that remotely measure atmospheric humidity in the upper troposphere of the Earth's atmosphere. The instruments made their measurements from 1984 to the present time; however, most of these instruments began operations after 2000, and only a few are still operational. The objective of this study is to quantify the accuracy of each satellite humidity data set.
Eric A. Ray, Elliot L. Atlas, Sue Schauffler, Sofia Chelpon, Laura Pan, Harald Bönisch, and Karen H. Rosenlof
Atmos. Chem. Phys., 22, 6539–6558, https://doi.org/10.5194/acp-22-6539-2022, https://doi.org/10.5194/acp-22-6539-2022, 2022
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The movement of air masses and the trace gases they contain from the Earth’s surface into the upper troposphere and lower stratosphere (UTLS) can have important implications for the radiative and chemical balance of the atmosphere. In this study we build on recent techniques and use new ones to estimate a range of transport diagnostics based on simultaneously measured trace gases in the UTLS during the monsoon season in North America.
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.
Cynthia H. Whaley, Rashed Mahmood, Knut von Salzen, Barbara Winter, Sabine Eckhardt, Stephen Arnold, Stephen Beagley, Silvia Becagli, Rong-You Chien, Jesper Christensen, Sujay Manish Damani, Xinyi Dong, Konstantinos Eleftheriadis, Nikolaos Evangeliou, Gregory Faluvegi, Mark Flanner, Joshua S. Fu, Michael Gauss, Fabio Giardi, Wanmin Gong, Jens Liengaard Hjorth, Lin Huang, Ulas Im, Yugo Kanaya, Srinath Krishnan, Zbigniew Klimont, Thomas Kühn, Joakim Langner, Kathy S. Law, Louis Marelle, Andreas Massling, Dirk Olivié, Tatsuo Onishi, Naga Oshima, Yiran Peng, David A. Plummer, Olga Popovicheva, Luca Pozzoli, Jean-Christophe Raut, Maria Sand, Laura N. Saunders, Julia Schmale, Sangeeta Sharma, Ragnhild Bieltvedt Skeie, Henrik Skov, Fumikazu Taketani, Manu A. Thomas, Rita Traversi, Kostas Tsigaridis, Svetlana Tsyro, Steven Turnock, Vito Vitale, Kaley A. Walker, Minqi Wang, Duncan Watson-Parris, and Tahya Weiss-Gibbons
Atmos. Chem. Phys., 22, 5775–5828, https://doi.org/10.5194/acp-22-5775-2022, https://doi.org/10.5194/acp-22-5775-2022, 2022
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Air pollutants, like ozone and soot, play a role in both global warming and air quality. Atmospheric models are often used to provide information to policy makers about current and future conditions under different emissions scenarios. In order to have confidence in those simulations, in this study we compare simulated air pollution from 18 state-of-the-art atmospheric models to measured air pollution in order to assess how well the models perform.
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.
Sheena Loeffel, Roland Eichinger, Hella Garny, Thomas Reddmann, Frauke Fritsch, Stefan Versick, Gabriele Stiller, and Florian Haenel
Atmos. Chem. Phys., 22, 1175–1193, https://doi.org/10.5194/acp-22-1175-2022, https://doi.org/10.5194/acp-22-1175-2022, 2022
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SF6-derived trends of stratospheric AoA from observations and model simulations disagree in sign. SF6 experiences chemical degradation, which we explicitly integrate in a global climate model. In our simulations, the AoA trend changes sign when SF6 sinks are considered; thus, the process has the potential to reconcile simulated with observed AoA trends. We show that the positive AoA trend is due to the SF6 sinks themselves and provide a first approach for a correction to account for SF6 loss.
Michael Höpfner, Oliver Kirner, Gerald Wetzel, Björn-Martin Sinnhuber, Florian Haenel, Sören Johansson, Johannes Orphal, Roland Ruhnke, Gabriele Stiller, and Thomas von Clarmann
Atmos. Chem. Phys., 21, 18433–18464, https://doi.org/10.5194/acp-21-18433-2021, https://doi.org/10.5194/acp-21-18433-2021, 2021
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BrONO2 is an important reservoir gas for inorganic stratospheric bromine linked to the chemical cycles of stratospheric ozone depletion. Presently infrared limb sounding is the only way to measure BrONO2 in the atmosphere. We provide global distributions of BrONO2 derived from MIPAS observations 2002–2012. Comparisons with EMAC atmospheric modelling show an overall agreement and enable us to derive an independent estimate of stratospheric bromine of 21.2±1.4pptv based on the BrONO2 measurements.
Paul D. Hamer, Virginie Marécal, Ryan Hossaini, Michel Pirre, Gisèle Krysztofiak, Franziska Ziska, Andreas Engel, Stephan Sala, Timo Keber, Harald Bönisch, Elliot Atlas, Kirstin Krüger, Martyn Chipperfield, Valery Catoire, Azizan A. Samah, Marcel Dorf, Phang Siew Moi, Hans Schlager, and Klaus Pfeilsticker
Atmos. Chem. Phys., 21, 16955–16984, https://doi.org/10.5194/acp-21-16955-2021, https://doi.org/10.5194/acp-21-16955-2021, 2021
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Bromoform is a stratospheric ozone-depleting gas released by seaweed and plankton transported to the stratosphere via convection in the tropics. We study the chemical interactions of bromoform and its derivatives within convective clouds using a cloud-scale model and observations. Our findings are that soluble bromine gases are efficiently washed out and removed within the convective clouds and that most bromine is transported vertically to the upper troposphere in the form of bromoform.
Marta Abalos, Natalia Calvo, Samuel Benito-Barca, Hella Garny, Steven C. Hardiman, Pu Lin, Martin B. Andrews, Neal Butchart, Rolando Garcia, Clara Orbe, David Saint-Martin, Shingo Watanabe, and Kohei Yoshida
Atmos. Chem. Phys., 21, 13571–13591, https://doi.org/10.5194/acp-21-13571-2021, https://doi.org/10.5194/acp-21-13571-2021, 2021
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The stratospheric Brewer–Dobson circulation (BDC), responsible for transporting mass, tracers and heat globally in the stratosphere, is evaluated in a set of state-of-the-art climate models. The acceleration of the BDC in response to increasing greenhouse gases is most robust in the lower stratosphere. At higher levels, the well-known inconsistency between model and observational BDC trends can be partly reconciled by accounting for limited sampling and large uncertainties in the observations.
Yenny Gonzalez, Róisín Commane, Ethan Manninen, Bruce C. Daube, Luke D. Schiferl, J. Barry McManus, Kathryn McKain, Eric J. Hintsa, James W. Elkins, Stephen A. Montzka, Colm Sweeney, Fred Moore, Jose L. Jimenez, Pedro Campuzano Jost, Thomas B. Ryerson, Ilann Bourgeois, Jeff Peischl, Chelsea R. Thompson, Eric Ray, Paul O. Wennberg, John Crounse, Michelle Kim, Hannah M. Allen, Paul A. Newman, Britton B. Stephens, Eric C. Apel, Rebecca S. Hornbrook, Benjamin A. Nault, Eric Morgan, and Steven C. Wofsy
Atmos. Chem. Phys., 21, 11113–11132, https://doi.org/10.5194/acp-21-11113-2021, https://doi.org/10.5194/acp-21-11113-2021, 2021
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Vertical profiles of N2O and a variety of chemical species and aerosols were collected nearly from pole to pole over the oceans during the NASA Atmospheric Tomography mission. We observed that tropospheric N2O variability is strongly driven by the influence of stratospheric air depleted in N2O, especially at middle and high latitudes. We also traced the origins of biomass burning and industrial emissions and investigated their impact on the variability of tropospheric N2O.
Christina J. Williamson, Agnieszka Kupc, Andrew Rollins, Jan Kazil, Karl D. Froyd, Eric A. Ray, Daniel M. Murphy, Gregory P. Schill, Jeff Peischl, Chelsea Thompson, Ilann Bourgeois, Thomas B. Ryerson, Glenn S. Diskin, Joshua P. DiGangi, Donald R. Blake, Thao Paul V. Bui, Maximilian Dollner, Bernadett Weinzierl, and Charles A. Brock
Atmos. Chem. Phys., 21, 9065–9088, https://doi.org/10.5194/acp-21-9065-2021, https://doi.org/10.5194/acp-21-9065-2021, 2021
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Aerosols in the stratosphere influence climate by scattering and absorbing sunlight and through chemical reactions occurring on the particles’ surfaces. We observed more nucleation mode aerosols (small aerosols, with diameters below 12 nm) in the mid- and high-latitude lowermost stratosphere (8–13 km) in the Northern Hemisphere (NH) than in the Southern Hemisphere. The most likely cause of this is aircraft emissions, which are concentrated in the NH at similar altitudes to our observations.
Thomas von Clarmann, Udo Grabowski, Gabriele P. Stiller, Beatriz M. Monge-Sanz, Norbert Glatthor, and Sylvia Kellmann
Atmos. Chem. Phys., 21, 8823–8843, https://doi.org/10.5194/acp-21-8823-2021, https://doi.org/10.5194/acp-21-8823-2021, 2021
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Measurements of long-lived trace gases (SF6, CFC-11, CFC-12, HCFC-12, CCl4, N2O, CH4, H2O, and CO) performed with the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) have been used to infer the stratospheric and mesospheric meridional circulation. The MIPAS data set covers the time period from July 2002 to April 2012. The method used for this purpose was the direct inversion of the two-dimensional continuity equation. Multiannual monthly mean circulation fields are presented.
Michael Kiefer, Thomas von Clarmann, Bernd Funke, Maya García-Comas, Norbert Glatthor, Udo Grabowski, Sylvia Kellmann, Anne Kleinert, Alexandra Laeng, Andrea Linden, Manuel López-Puertas, Daniel R. Marsh, and Gabriele P. Stiller
Atmos. Meas. Tech., 14, 4111–4138, https://doi.org/10.5194/amt-14-4111-2021, https://doi.org/10.5194/amt-14-4111-2021, 2021
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An improved dataset of vertical temperature profiles of the Earth's atmosphere in the altitude range 5–70 km is presented. These profiles are derived from measurements of the MIPAS instrument onboard ESA's Envisat satellite. The overall improvements are based on upgrades in the input data and several improvements in the data processing approach. Both of these are discussed, and an extensive error discussion is included. Enhancements of the new dataset are demonstrated by means of examples.
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.
Max Thomas, Johannes C. Laube, Jan Kaiser, Samuel Allin, Patricia Martinerie, Robert Mulvaney, Anna Ridley, Thomas Röckmann, William T. Sturges, and Emmanuel Witrant
Atmos. Chem. Phys., 21, 6857–6873, https://doi.org/10.5194/acp-21-6857-2021, https://doi.org/10.5194/acp-21-6857-2021, 2021
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CFC gases are destroying the Earth's life-protecting ozone layer. We improve understanding of CFC destruction by measuring the isotopic fingerprint of the carbon in the three most abundant CFCs. These are the first such measurements in the main region where CFCs are destroyed – the stratosphere. We reconstruct the atmospheric isotope histories of these CFCs back to the 1950s by measuring air extracted from deep snow and using a model. The model and the measurements are generally consistent.
Simone Dietmüller, Hella Garny, Roland Eichinger, and William T. Ball
Atmos. Chem. Phys., 21, 6811–6837, https://doi.org/10.5194/acp-21-6811-2021, https://doi.org/10.5194/acp-21-6811-2021, 2021
Viktoria F. Sofieva, Monika Szeląg, Johanna Tamminen, Erkki Kyrölä, Doug Degenstein, Chris Roth, Daniel Zawada, Alexei Rozanov, Carlo Arosio, John P. Burrows, Mark Weber, Alexandra Laeng, Gabriele P. Stiller, Thomas von Clarmann, Lucien Froidevaux, Nathaniel Livesey, Michel van Roozendael, and Christian Retscher
Atmos. Chem. Phys., 21, 6707–6720, https://doi.org/10.5194/acp-21-6707-2021, https://doi.org/10.5194/acp-21-6707-2021, 2021
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The MErged GRIdded Dataset of Ozone Profiles is a long-term (2001–2018) stratospheric ozone profile climate data record with resolved longitudinal structure that combines the data from six limb satellite instruments. The dataset can be used for various analyses, some of which are discussed in the paper. In particular, regionally and vertically resolved ozone trends are evaluated, including trends in the polar regions.
Yuming Jin, Ralph F. Keeling, Eric J. Morgan, Eric Ray, Nicholas C. Parazoo, and Britton B. Stephens
Atmos. Chem. Phys., 21, 217–238, https://doi.org/10.5194/acp-21-217-2021, https://doi.org/10.5194/acp-21-217-2021, 2021
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We propose a new atmospheric coordinate (Mθe) based on equivalent potential temperature (θe) but with mass as the unit. This coordinate is useful in studying the spatial and temporal distribution of long-lived chemical tracers (CO2, CH4, O2 / N2, etc.) from sparse data, like airborne observation. Using this coordinate and sparse airborne observation (HIPPO and ATom), we resolve the Northern Hemisphere mass-weighted average CO2 seasonal cycle with high accuracy.
Agnieszka Kupc, Christina J. Williamson, Anna L. Hodshire, Jan Kazil, Eric Ray, T. Paul Bui, Maximilian Dollner, Karl D. Froyd, Kathryn McKain, Andrew Rollins, Gregory P. Schill, Alexander Thames, Bernadett B. Weinzierl, Jeffrey R. Pierce, and Charles A. Brock
Atmos. Chem. Phys., 20, 15037–15060, https://doi.org/10.5194/acp-20-15037-2020, https://doi.org/10.5194/acp-20-15037-2020, 2020
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Tropical upper troposphere over the Atlantic and Pacific oceans is a major source region of new particles. These particles are associated with the outflow from deep convection. We investigate the processes that govern the formation of these particles and their initial growth and show that none of the formation schemes commonly used in global models are consistent with observations. Using newer schemes indicates that organic compounds are likely important as nucleating and initial growth agents.
Hella Garny, Roland Walz, Matthias Nützel, and Thomas Birner
Geosci. Model Dev., 13, 5229–5257, https://doi.org/10.5194/gmd-13-5229-2020, https://doi.org/10.5194/gmd-13-5229-2020, 2020
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Numerical models of Earth's climate system have been gaining more and more complexity over the last decades. Therefore, it is important to establish simplified models to improve process understanding. In our study, we present and document the development of a new simplified model setup within the framework of a complex climate model system that uses the same routines to calculate atmospheric dynamics as the complex model but is simplified in the representation of clouds and radiation.
Benjamin Birner, Martyn P. Chipperfield, Eric J. Morgan, Britton B. Stephens, Marianna Linz, Wuhu Feng, Chris Wilson, Jonathan D. Bent, Steven C. Wofsy, Jeffrey Severinghaus, and Ralph F. Keeling
Atmos. Chem. Phys., 20, 12391–12408, https://doi.org/10.5194/acp-20-12391-2020, https://doi.org/10.5194/acp-20-12391-2020, 2020
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With new high-precision observations from nine aircraft campaigns and 3-D chemical transport modeling, we show that the argon-to-nitrogen ratio (Ar / N2) in the lowermost stratosphere provides a useful constraint on the “age of air” (the time elapsed since entry of an air parcel into the stratosphere). Therefore, Ar / N2 in combination with traditional age-of-air indicators, such as CO2 and N2O, could provide new insights into atmospheric mixing and transport.
Ales Kuchar, Petr Sacha, Roland Eichinger, Christoph Jacobi, Petr Pisoft, and Harald E. Rieder
Weather Clim. Dynam., 1, 481–495, https://doi.org/10.5194/wcd-1-481-2020, https://doi.org/10.5194/wcd-1-481-2020, 2020
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Our study focuses on the impact of topographic structures such as the Himalayas and Rocky Mountains, so-called orographic gravity-wave hotspots. These hotspots play an important role in the dynamics of the middle atmosphere, in particular in the lower stratosphere. We study intermittency and zonally asymmetric character of these hotspots and their effects on the upper stratosphere and mesosphere using a new detection method in various modeling and observational datasets.
Ilann Bourgeois, Jeff Peischl, Chelsea R. Thompson, Kenneth C. Aikin, Teresa Campos, Hannah Clark, Róisín Commane, Bruce Daube, Glenn W. Diskin, James W. Elkins, Ru-Shan Gao, Audrey Gaudel, Eric J. Hintsa, Bryan J. Johnson, Rigel Kivi, Kathryn McKain, Fred L. Moore, David D. Parrish, Richard Querel, Eric Ray, Ricardo Sánchez, Colm Sweeney, David W. Tarasick, Anne M. Thompson, Valérie Thouret, Jacquelyn C. Witte, Steve C. Wofsy, and Thomas B. Ryerson
Atmos. Chem. Phys., 20, 10611–10635, https://doi.org/10.5194/acp-20-10611-2020, https://doi.org/10.5194/acp-20-10611-2020, 2020
Johannes C. Laube, Emma C. Leedham Elvidge, Karina E. Adcock, Bianca Baier, Carl A. M. Brenninkmeijer, Huilin Chen, Elise S. Droste, Jens-Uwe Grooß, Pauli Heikkinen, Andrew J. Hind, Rigel Kivi, Alexander Lojko, Stephen A. Montzka, David E. Oram, Steve Randall, Thomas Röckmann, William T. Sturges, Colm Sweeney, Max Thomas, Elinor Tuffnell, and Felix Ploeger
Atmos. Chem. Phys., 20, 9771–9782, https://doi.org/10.5194/acp-20-9771-2020, https://doi.org/10.5194/acp-20-9771-2020, 2020
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We demonstrate that AirCore technology, which is based on small low-cost balloons, can provide access to trace gas measurements such as CFCs at ultra-low abundances. This is a new way to quantify ozone-depleting, and related, substances in the stratosphere, which is largely inaccessible to aircraft. We show two potential uses: (a) tracking the stratospheric circulation, which is predicted to change, and (b) assessing three common meteorological reanalyses driving a global stratospheric model.
Thomas von Clarmann, Douglas A. Degenstein, Nathaniel J. Livesey, Stefan Bender, Amy Braverman, André Butz, Steven Compernolle, Robert Damadeo, Seth Dueck, Patrick Eriksson, Bernd Funke, Margaret C. Johnson, Yasuko Kasai, Arno Keppens, Anne Kleinert, Natalya A. Kramarova, Alexandra Laeng, Bavo Langerock, Vivienne H. Payne, Alexei Rozanov, Tomohiro O. Sato, Matthias Schneider, Patrick Sheese, Viktoria Sofieva, Gabriele P. Stiller, Christian von Savigny, and Daniel Zawada
Atmos. Meas. Tech., 13, 4393–4436, https://doi.org/10.5194/amt-13-4393-2020, https://doi.org/10.5194/amt-13-4393-2020, 2020
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Remote sensing of atmospheric state variables typically relies on the inverse solution of the radiative transfer equation. An adequately characterized retrieval provides information on the uncertainties of the estimated state variables as well as on how any constraint or a priori assumption affects the estimate. This paper summarizes related techniques and provides recommendations for unified error reporting.
Temesgen Yirdaw Berhe, Gizaw Mengistu Tsidu, Thomas Blumenstock, Frank Hase, and Gabriele P. Stiller
Atmos. Meas. Tech., 13, 4079–4096, https://doi.org/10.5194/amt-13-4079-2020, https://doi.org/10.5194/amt-13-4079-2020, 2020
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The retrieved CH4 and N2O VMR and column amounts from Addis Ababa, tropical site, are found to exhibit very good agreement with all coincident satellite observations (MIPAS, MLS, and AIRS). Furthermore, the bias obtained from the comparison is comparable to the precision of FTIR measurement, which allows the use of data in further scientific studies as it represents a unique environment of tropical Africa, a region poorly investigated in the past.
Marius Hauck, Harald Bönisch, Peter Hoor, Timo Keber, Felix Ploeger, Tanja J. Schuck, and Andreas Engel
Atmos. Chem. Phys., 20, 8763–8785, https://doi.org/10.5194/acp-20-8763-2020, https://doi.org/10.5194/acp-20-8763-2020, 2020
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This study features an extended inversion method that includes transport across the extratropical tropopause to derive age spectra in the lowermost stratosphere from in situ trace gas measurements. The refined method is validated in a model setup and applied to data gained with the HALO research aircraft. Results are congruent with the findings of previous studies so that the method provides a promising toolset for the analysis of stratospheric dynamics based on observations in the future.
Frauke Fritsch, Hella Garny, Andreas Engel, Harald Bönisch, and Roland Eichinger
Atmos. Chem. Phys., 20, 8709–8725, https://doi.org/10.5194/acp-20-8709-2020, https://doi.org/10.5194/acp-20-8709-2020, 2020
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We test two methods to derive age of air as a diagnostic of the Brewer–Dobson circulation from non-linear increasing trace gases such as SF6 using a chemistry-climate model and observations. Both the model and the observations show systematic variation of the age of air trend dependent on the chosen assumptions that are required when deriving age of air from measurements. This provides insight into the differences in age of air trends of observations and models.
Rostislav Kouznetsov, Mikhail Sofiev, Julius Vira, and Gabriele Stiller
Atmos. Chem. Phys., 20, 5837–5859, https://doi.org/10.5194/acp-20-5837-2020, https://doi.org/10.5194/acp-20-5837-2020, 2020
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Estimates of the age of stratospheric air (AoA), its distribution, and trends, obtained by different experimental methods, differ among each other. AoA derived form MIPAS satellite observations, the richest observational dataset on sulfur hexafluoride (SF6) in the stratosphere, are a clear outlier. With multi-decade simulations of AoA and SF6 in the stratosphere, we show that the origin of the discrepancy is in a methodology of deriving AoA from observations rather than in observational data.
Elise S. Droste, Karina E. Adcock, Matthew J. Ashfold, Charles Chou, Zoë Fleming, Paul J. Fraser, Lauren J. Gooch, Andrew J. Hind, Ray L. Langenfelds, Emma C. Leedham Elvidge, Norfazrin Mohd Hanif, Simon O'Doherty, David E. Oram, Chang-Feng Ou-Yang, Marios Panagi, Claire E. Reeves, William T. Sturges, and Johannes C. Laube
Atmos. Chem. Phys., 20, 4787–4807, https://doi.org/10.5194/acp-20-4787-2020, https://doi.org/10.5194/acp-20-4787-2020, 2020
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We update the tropospheric trends and emissions of six perfluorocarbon (PFC) gases, including separate isomers. Trends for these strong greenhouse gases are still increasing, but at slower rates than previously. The lack of natural sinks results in the global accumulation of 833 million metric tonnes of CO2 equivalent for these six PFCs by 2017. Modelling results indicate potential source regions and types in East Asia, but we find that many emissions are unaccounted for in emission reports.
Alma Hodzic, Pedro Campuzano-Jost, Huisheng Bian, Mian Chin, Peter R. Colarco, Douglas A. Day, Karl D. Froyd, Bernd Heinold, Duseong S. Jo, Joseph M. Katich, John K. Kodros, Benjamin A. Nault, Jeffrey R. Pierce, Eric Ray, Jacob Schacht, Gregory P. Schill, Jason C. Schroder, Joshua P. Schwarz, Donna T. Sueper, Ina Tegen, Simone Tilmes, Kostas Tsigaridis, Pengfei Yu, and Jose L. Jimenez
Atmos. Chem. Phys., 20, 4607–4635, https://doi.org/10.5194/acp-20-4607-2020, https://doi.org/10.5194/acp-20-4607-2020, 2020
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Organic aerosol (OA) is a key source of uncertainty in aerosol climate effects. We present the first pole-to-pole OA characterization during the NASA Atmospheric Tomography aircraft mission. OA has a strong seasonal and zonal variability, with the highest levels in summer and over fire-influenced regions and the lowest ones in the southern high latitudes. We show that global models predict the OA distribution well but not the relative contribution of OA emissions vs. chemical production.
Timo Keber, Harald Bönisch, Carl Hartick, Marius Hauck, Fides Lefrancois, Florian Obersteiner, Akima Ringsdorf, Nils Schohl, Tanja Schuck, Ryan Hossaini, Phoebe Graf, Patrick Jöckel, and Andreas Engel
Atmos. Chem. Phys., 20, 4105–4132, https://doi.org/10.5194/acp-20-4105-2020, https://doi.org/10.5194/acp-20-4105-2020, 2020
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In this paper we summarize observations of short-lived halocarbons in the tropopause region. We show that, especially during winter, the levels of short-lived bromine gases at the extratropical tropopause are higher than at the tropical tropopause. We discuss the impact of the distributions on stratospheric bromine levels and compare our observations to two models with four different emission scenarios.
Nicholas A. Davis, Sean M. Davis, Robert W. Portmann, Eric Ray, Karen H. Rosenlof, and Pengfei Yu
Geosci. Model Dev., 13, 717–734, https://doi.org/10.5194/gmd-13-717-2020, https://doi.org/10.5194/gmd-13-717-2020, 2020
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Large-scale waves drive upward motion in the tropical stratosphere, with major impacts on stratospheric chemistry and climate. However, some of the modeling methods which attempt to simulate the past evolution of the stratosphere do not seem to be able to recreate important trends. We believe this is due to disagreements between the basic climate of the model and observations, but if the method is constructed more carefully, the disagreement becomes smaller and the trends become more realistic.
Stefan Lossow, Charlotta Högberg, Farahnaz Khosrawi, Gabriele P. Stiller, Ralf Bauer, Kaley A. Walker, Sylvia Kellmann, Andrea Linden, Michael Kiefer, Norbert Glatthor, Thomas von Clarmann, Donal P. Murtagh, Jörg Steinwagner, Thomas Röckmann, and Roland Eichinger
Atmos. Meas. Tech., 13, 287–308, https://doi.org/10.5194/amt-13-287-2020, https://doi.org/10.5194/amt-13-287-2020, 2020
Maxime Prignon, Simon Chabrillat, Daniele Minganti, Simon O'Doherty, Christian Servais, Gabriele Stiller, Geoffrey C. Toon, Martin K. Vollmer, and Emmanuel Mahieu
Atmos. Chem. Phys., 19, 12309–12324, https://doi.org/10.5194/acp-19-12309-2019, https://doi.org/10.5194/acp-19-12309-2019, 2019
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Hydrochlorofluorocarbons (HCFCs) are the first, but temporary, substitution products for the strong ozone-depleting chlorofluorocarbons (CFCs). In this work, we present and validate an improved method to retrieve the most abundant HCFC in the atmosphere, allowing its evolution to be monitored independently in the troposphere and stratosphere. These kinds of contributions are fundamental for scrutinizing the fulfilment of the Montreal Protocol on Substances that Deplete the Ozone Layer.
Andreas Chrysanthou, Amanda C. Maycock, Martyn P. Chipperfield, Sandip Dhomse, Hella Garny, Douglas Kinnison, Hideharu Akiyoshi, Makoto Deushi, Rolando R. Garcia, Patrick Jöckel, Oliver Kirner, Giovanni Pitari, David A. Plummer, Laura Revell, Eugene Rozanov, Andrea Stenke, Taichu Y. Tanaka, Daniele Visioni, and Yousuke Yamashita
Atmos. Chem. Phys., 19, 11559–11586, https://doi.org/10.5194/acp-19-11559-2019, https://doi.org/10.5194/acp-19-11559-2019, 2019
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We perform the first multi-model comparison of the impact of nudged meteorology on the stratospheric residual circulation (RC) in chemistry–climate models. Nudging meteorology does not constrain the mean strength of RC compared to free-running simulations, and despite the lack of agreement in the mean circulation, nudging tightly constrains the inter-annual variability in the tropical upward mass flux in the lower stratosphere. In summary, nudging strongly affects the representation of RC.
Dan Weaver, Kimberly Strong, Kaley A. Walker, Chris Sioris, Matthias Schneider, C. Thomas McElroy, Holger Vömel, Michael Sommer, Katja Weigel, Alexei Rozanov, John P. Burrows, William G. Read, Evan Fishbein, and Gabriele Stiller
Atmos. Meas. Tech., 12, 4039–4063, https://doi.org/10.5194/amt-12-4039-2019, https://doi.org/10.5194/amt-12-4039-2019, 2019
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This work assesses water vapour profiles acquired by Atmospheric Chemistry Experiment (ACE) satellite instruments in the upper troposphere and lower stratosphere (UTLS) using comparisons to radiosondes and ground-based Fourier transform infrared spectrometer measurements acquired at a Canadian high Arctic measurement site in Eureka, Nunavut. Additional comparisons are made between these Eureka measurements and other water vapour satellite datasets for context, including AIRS, MLS, and others.
Matthias Nützel, Aurélien Podglajen, Hella Garny, and Felix Ploeger
Atmos. Chem. Phys., 19, 8947–8966, https://doi.org/10.5194/acp-19-8947-2019, https://doi.org/10.5194/acp-19-8947-2019, 2019
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We investigate the transport pathways of water vapour from the upper troposphere in the Asian monsoon region to the stratosphere. In the employed chemistry-transport model we use a tagging method, such that the impact of different source regions on the stratospheric water vapour budget can be quantified. A key finding is that the Asian monsoon (compared to other source regions) is very efficient in transporting air masses and water vapour to the tropical and extratropical stratosphere.
Petr Šácha, Roland Eichinger, Hella Garny, Petr Pišoft, Simone Dietmüller, Laura de la Torre, David A. Plummer, Patrick Jöckel, Olaf Morgenstern, Guang Zeng, Neal Butchart, and Juan A. Añel
Atmos. Chem. Phys., 19, 7627–7647, https://doi.org/10.5194/acp-19-7627-2019, https://doi.org/10.5194/acp-19-7627-2019, 2019
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Climate models robustly project a Brewer–Dobson circulation (BDC) acceleration in the course of climate change. Analyzing mean age of stratospheric air (AoA) from a subset of climate projection simulations, we find a remarkable agreement in simulating the largest AoA trends in the extratropical stratosphere. This is shown to be related with the upward shift of the circulation, resulting in a so-called stratospheric shrinkage, which could be one of the so-far-omitted BDC acceleration drivers.
Stefan Lossow, Farahnaz Khosrawi, Michael Kiefer, Kaley A. Walker, Jean-Loup Bertaux, Laurent Blanot, James M. Russell, Ellis E. Remsberg, John C. Gille, Takafumi Sugita, Christopher E. Sioris, Bianca M. Dinelli, Enzo Papandrea, Piera Raspollini, Maya García-Comas, Gabriele P. Stiller, Thomas von Clarmann, Anu Dudhia, William G. Read, Gerald E. Nedoluha, Robert P. Damadeo, Joseph M. Zawodny, Katja Weigel, Alexei Rozanov, Faiza Azam, Klaus Bramstedt, Stefan Noël, John P. Burrows, Hideo Sagawa, Yasuko Kasai, Joachim Urban, Patrick Eriksson, Donal P. Murtagh, Mark E. Hervig, Charlotta Högberg, Dale F. Hurst, and Karen H. Rosenlof
Atmos. Meas. Tech., 12, 2693–2732, https://doi.org/10.5194/amt-12-2693-2019, https://doi.org/10.5194/amt-12-2693-2019, 2019
Bärbel Vogel, Rolf Müller, Gebhard Günther, Reinhold Spang, Sreeharsha Hanumanthu, Dan Li, Martin Riese, and Gabriele P. Stiller
Atmos. Chem. Phys., 19, 6007–6034, https://doi.org/10.5194/acp-19-6007-2019, https://doi.org/10.5194/acp-19-6007-2019, 2019
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We identified the transport pathways of air masses from the region of the Asian monsoon (e.g. pollution and greenhouse gases caused by increasing population and growing industries in Asia) into the lower stratosphere. Even small changes of the chemical composition of the lower stratosphere have an impact on surface climate (e.g. surface temperatures). Therefore, it is important to identify transport pathways to the stratosphere to allow potential environmental risks to be assessed.
Marius Hauck, Frauke Fritsch, Hella Garny, and Andreas Engel
Atmos. Chem. Phys., 19, 5269–5291, https://doi.org/10.5194/acp-19-5269-2019, https://doi.org/10.5194/acp-19-5269-2019, 2019
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The paper presents a modified method to invert mixing ratios of chemically active tracers into stratospheric age spectra. It features an imposed seasonal cycle to include transport seasonality into the spectra. An idealized set of tracers from a model is used as proof of concept and results are in good agreement with the model reference, except for the lowermost stratosphere. Applicability is studied with focus on number of tracers and error tolerance, providing a starting point for future work.
Marianna Linz, Marta Abalos, Anne Sasha Glanville, Douglas E. Kinnison, Alison Ming, and Jessica L. Neu
Atmos. Chem. Phys., 19, 5069–5090, https://doi.org/10.5194/acp-19-5069-2019, https://doi.org/10.5194/acp-19-5069-2019, 2019
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The stratospheric circulation is important for transporting ozone and water vapor, and models of the stratosphere differ. The metrics used to compare models are inconsistent between studies and cannot be calculated from observational data. In this paper, we explore a metric for the circulation that can be calculated from observations and examine how it relates to the more commonly used metrics. We find substantial differences in the upper and lower stratosphere depending on the choice of metric.
Charlotta Högberg, Stefan Lossow, Farahnaz Khosrawi, Ralf Bauer, Kaley A. Walker, Patrick Eriksson, Donal P. Murtagh, Gabriele P. Stiller, Jörg Steinwagner, and Qiong Zhang
Atmos. Chem. Phys., 19, 2497–2526, https://doi.org/10.5194/acp-19-2497-2019, https://doi.org/10.5194/acp-19-2497-2019, 2019
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Five δD (H2O) data sets obtained from satellite observations have been evaluated using profile-to-profile and climatological comparisons. The focus is on stratospheric altitudes, but results from the upper troposphere to the lower mesosphere are also provided. There are clear quantitative differences in the δD ratio in key areas of scientific interest, resulting in difficulties drawing robust conclusions on atmospheric processes affecting the water vapour budget and distribution.
Roland Eichinger, Simone Dietmüller, Hella Garny, Petr Šácha, Thomas Birner, Harald Bönisch, Giovanni Pitari, Daniele Visioni, Andrea Stenke, Eugene Rozanov, Laura Revell, David A. Plummer, Patrick Jöckel, Luke Oman, Makoto Deushi, Douglas E. Kinnison, Rolando Garcia, Olaf Morgenstern, Guang Zeng, Kane Adam Stone, and Robyn Schofield
Atmos. Chem. Phys., 19, 921–940, https://doi.org/10.5194/acp-19-921-2019, https://doi.org/10.5194/acp-19-921-2019, 2019
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To shed more light upon the changes in stratospheric circulation in the 21st century, climate projection simulations of 10 state-of-the-art global climate models, spanning from 1960 to 2100, are analyzed. The study shows that in addition to changes in transport, mixing also plays an important role in stratospheric circulation and that the properties of mixing vary over time. Furthermore, the influence of mixing is quantified and a dynamical framework is provided to understand the changes.
Tanja J. Schuck, Fides Lefrancois, Franziska Gallmann, Danrong Wang, Markus Jesswein, Jesica Hoker, Harald Bönisch, and Andreas Engel
Atmos. Chem. Phys., 18, 16553–16569, https://doi.org/10.5194/acp-18-16553-2018, https://doi.org/10.5194/acp-18-16553-2018, 2018
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We present the first results of regular halocarbon measurements at Taunus Observatory, Germany. Halogenated gases contribute to stratospheric ozone depletion and to radiative forcing. Time-of-flight mass spectrometry allows one to assess a large number of compounds; the measurements are expected to provide better constraints for European emission estimates. CFC-11 and CFC-12 show small unexpected differences regarding outlier occurrence and seasonality, indicating ongoing emissions of CFC-11.
Michael Höpfner, Terry Deshler, Michael Pitts, Lamont Poole, Reinhold Spang, Gabriele Stiller, and Thomas von Clarmann
Atmos. Meas. Tech., 11, 5901–5923, https://doi.org/10.5194/amt-11-5901-2018, https://doi.org/10.5194/amt-11-5901-2018, 2018
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Polar stratospheric clouds (PSC) have major relevance to the processes leading to polar ozone depletion. A good understanding of these particles is a prerequisite to predict their role in a changing climate. We present the first global set of PSC volume density profiles derived from the MIPAS satellite measurements covering the entire mission period between 2002 and 2012. A comparison to CALIOP lidar measurements is provided. The dataset can serve as a basis for evaluation of atmospheric models.
Franz Slemr, Andreas Weigelt, Ralf Ebinghaus, Johannes Bieser, Carl A. M. Brenninkmeijer, Armin Rauthe-Schöch, Markus Hermann, Bengt G. Martinsson, Peter van Velthoven, Harald Bönisch, Marco Neumaier, Andreas Zahn, and Helmut Ziereis
Atmos. Chem. Phys., 18, 12329–12343, https://doi.org/10.5194/acp-18-12329-2018, https://doi.org/10.5194/acp-18-12329-2018, 2018
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Total and elemental mercury were measured in the upper troposphere and lower stratosphere onboard a passenger aircraft. Their concentrations in the upper troposphere were comparable implying low concentrations of oxidized mercury in this region. Large scale seasonally dependent influence of emissions from biomass burning was also observed. Their distributions in the lower stratosphere implies a long stratospheric lifetime, which precludes significant mercury oxidation by ozone.
Norbert Glatthor, Thomas von Clarmann, Gabriele P. Stiller, Michael Kiefer, Alexandra Laeng, Bianca M. Dinelli, Gerald Wetzel, and Johannes Orphal
Atmos. Meas. Tech., 11, 4707–4723, https://doi.org/10.5194/amt-11-4707-2018, https://doi.org/10.5194/amt-11-4707-2018, 2018
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We report differences in ozone retrievals in channels A and AB of the space-borne Michelson Interferometer for Passive Atmospheric Sounding (MIPAS), which amount to up to 8 %. We provide strong evidence that the bias is caused by inconsistencies in different spectroscopic databases (MIPAS, HITRAN, GEISA). We show that a major part of the differences can be attributed to inconsistent air-broadening coefficients of the ozone lines contained in the databases.
Alexandra Laeng, Ellen Eckert, Thomas von Clarmann, Michael Kiefer, Daan Hubert, Gabriele Stiller, Norbert Glatthor, Manuel López-Puertas, Bernd Funke, Udo Grabowski, Johannes Plieninger, Sylvia Kellmann, Andrea Linden, Stefan Lossow, Arne Babenhauserheide, Lucien Froidevaux, and Kaley Walker
Atmos. Meas. Tech., 11, 4693–4705, https://doi.org/10.5194/amt-11-4693-2018, https://doi.org/10.5194/amt-11-4693-2018, 2018
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MIPAS was an IR limb emission spectrometer on the Envisat platform. From 2002 to 2012, it performed pole-to-pole measurements of ozone during day and night. ESA recently released the new version 7 of Level 1 MIPAS spectra, which is expected to reduce the long-term drift of the MIPAS Level 2 data. We evaluate the long-term stability of ozone Level 2 data from the KIT IMK processor. Our results indicate that MIPAS data are now even more suited for trend studies, alone or as part of merged data.
Farahnaz Khosrawi, Stefan Lossow, Gabriele P. Stiller, Karen H. Rosenlof, Joachim Urban, John P. Burrows, Robert P. Damadeo, Patrick Eriksson, Maya García-Comas, John C. Gille, Yasuko Kasai, Michael Kiefer, Gerald E. Nedoluha, Stefan Noël, Piera Raspollini, William G. Read, Alexei Rozanov, Christopher E. Sioris, Kaley A. Walker, and Katja Weigel
Atmos. Meas. Tech., 11, 4435–4463, https://doi.org/10.5194/amt-11-4435-2018, https://doi.org/10.5194/amt-11-4435-2018, 2018
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Time series of stratospheric and lower mesospheric water vapour using 33 data sets from 15 satellite instruments were compared in the framework of the second SPARC water vapour assessment. We find that most data sets can be considered in observational and modelling studies addressing, e.g. stratospheric and lower mesospheric water vapour variability and trends if data-set-specific characteristics (e.g. a drift) and restrictions (e.g. temporal and spatial coverage) are taken into account.
Farahnaz Khosrawi, Oliver Kirner, Gabriele Stiller, Michael Höpfner, Michelle L. Santee, Sylvia Kellmann, and Peter Braesicke
Atmos. Chem. Phys., 18, 8873–8892, https://doi.org/10.5194/acp-18-8873-2018, https://doi.org/10.5194/acp-18-8873-2018, 2018
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An extensive assessment of the performance of the chemistry–climate model EMAC is given for Arctic winters 2009/2010 and 2010/2011. The EMAC simulations are compared to satellite observations. The comparisons between EMAC simulations and satellite observations show that model and measurements compare well for these two Arctic winters. However, differences between model and observations are found that need improvements in the model in the future.
Stefan Lossow, Dale F. Hurst, Karen H. Rosenlof, Gabriele P. Stiller, Thomas von Clarmann, Sabine Brinkop, Martin Dameris, Patrick Jöckel, Doug E. Kinnison, Johannes Plieninger, David A. Plummer, Felix Ploeger, William G. Read, Ellis E. Remsberg, James M. Russell, and Mengchu Tao
Atmos. Chem. Phys., 18, 8331–8351, https://doi.org/10.5194/acp-18-8331-2018, https://doi.org/10.5194/acp-18-8331-2018, 2018
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Trend estimates of lower stratospheric H2O derived from the FPH observations at Boulder and a merged zonal mean satellite data set clearly differ for the time period from the late 1980s to 2010. We investigate if a sampling bias between Boulder and the zonal mean around the Boulder latitude can explain these trend discrepancies. Typically they are small and not sufficient to explain the trend discrepancies in the observational database.
Felicia Kolonjari, David A. Plummer, Kaley A. Walker, Chris D. Boone, James W. Elkins, Michaela I. Hegglin, Gloria L. Manney, Fred L. Moore, Diane Pendlebury, Eric A. Ray, Karen H. Rosenlof, and Gabriele P. Stiller
Atmos. Chem. Phys., 18, 6801–6828, https://doi.org/10.5194/acp-18-6801-2018, https://doi.org/10.5194/acp-18-6801-2018, 2018
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We used satellite observations and model simulations of CFC-11, CFC-12, and N2O to investigate stratospheric transport, which is important for predicting the recovery of the ozone layer and future climate. We found that sampling can impact results and that the model consistently overestimates concentrations of these gases in the lower stratosphere, consistent with a too rapid Brewer–Dobson circulation. An issue with mixing in the tropical lower stratosphere in June–July–August was also found.
Simone Dietmüller, Roland Eichinger, Hella Garny, Thomas Birner, Harald Boenisch, Giovanni Pitari, Eva Mancini, Daniele Visioni, Andrea Stenke, Laura Revell, Eugene Rozanov, David A. Plummer, John Scinocca, Patrick Jöckel, Luke Oman, Makoto Deushi, Shibata Kiyotaka, Douglas E. Kinnison, Rolando Garcia, Olaf Morgenstern, Guang Zeng, Kane Adam Stone, and Robyn Schofield
Atmos. Chem. Phys., 18, 6699–6720, https://doi.org/10.5194/acp-18-6699-2018, https://doi.org/10.5194/acp-18-6699-2018, 2018
Jens Krause, Peter Hoor, Andreas Engel, Felix Plöger, Jens-Uwe Grooß, Harald Bönisch, Timo Keber, Björn-Martin Sinnhuber, Wolfgang Woiwode, and Hermann Oelhaf
Atmos. Chem. Phys., 18, 6057–6073, https://doi.org/10.5194/acp-18-6057-2018, https://doi.org/10.5194/acp-18-6057-2018, 2018
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We present tracer measurements of CO and N2O measured during the POLSTRACC aircraft campaign in winter 2015–2016. We found enhanced CO values relative to N2O in the polar lower stratosphere in addition to the ageing of this region during winter. By using model simulations it was possible to link this enhancement to an increased mixing of the tropical tropopause. We thus conclude that the polar lower stratosphere in late winter is strongly influenced by quasi-isentropic mixing from the tropics.
Manuel López-Puertas, Maya García-Comas, Bernd Funke, Angela Gardini, Gabriele P. Stiller, Thomas von Clarmann, Norbert Glatthor, Alexandra Laeng, Martin Kaufmann, Viktoria F. Sofieva, Lucien Froidevaux, Kaley A. Walker, and Masato Shiotani
Atmos. Meas. Tech., 11, 2187–2212, https://doi.org/10.5194/amt-11-2187-2018, https://doi.org/10.5194/amt-11-2187-2018, 2018
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This paper describes the inversion of O3 data from MIPAS middle atmosphere spectra which requires non-LTE. The O3 dataset comprises from 20 to 100 km, has a pole-to-pole latitude coverage, day and nighttime, and span from 2005 until 2012. A validation of the data against other satellite measurements and an overall description of O3 is also presented. This is an important dataset for the community and describes the major characteristics of stratospheric and mesospheric O3.
Karina E. Adcock, Claire E. Reeves, Lauren J. Gooch, Emma C. Leedham Elvidge, Matthew J. Ashfold, Carl A. M. Brenninkmeijer, Charles Chou, Paul J. Fraser, Ray L. Langenfelds, Norfazrin Mohd Hanif, Simon O'Doherty, David E. Oram, Chang-Feng Ou-Yang, Siew Moi Phang, Azizan Abu Samah, Thomas Röckmann, William T. Sturges, and Johannes C. Laube
Atmos. Chem. Phys., 18, 4737–4751, https://doi.org/10.5194/acp-18-4737-2018, https://doi.org/10.5194/acp-18-4737-2018, 2018
Emma C. Leedham Elvidge, Harald Bönisch, Carl A. M. Brenninkmeijer, Andreas Engel, Paul J. Fraser, Eileen Gallacher, Ray Langenfelds, Jens Mühle, David E. Oram, Eric A. Ray, Anna R. Ridley, Thomas Röckmann, William T. Sturges, Ray F. Weiss, and Johannes C. Laube
Atmos. Chem. Phys., 18, 3369–3385, https://doi.org/10.5194/acp-18-3369-2018, https://doi.org/10.5194/acp-18-3369-2018, 2018
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Chemical species measured in stratospheric air can be used as proxies for stratospheric circulation changes which cannot be measured directly. A range of tracers is important to understand changing stratospheric dynamics. We demonstrate the suitability of PFCs and HFCs as tracers and support recent work that reduces the current stratospheric lifetime of SF6. Updates to policy-relevant parameters (e.g. stratospheric lifetime) linked to this change are provided for O3-depleting substances.
Minqiang Zhou, Bavo Langerock, Corinne Vigouroux, Pucai Wang, Christian Hermans, Gabriele Stiller, Kaley A. Walker, Geoff Dutton, Emmanuel Mahieu, and Martine De Mazière
Atmos. Meas. Tech., 11, 651–662, https://doi.org/10.5194/amt-11-651-2018, https://doi.org/10.5194/amt-11-651-2018, 2018
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SF6 total columns are successfully retrieved from FTIR measurements (Saint Denis and Maïdo) at Reunion Island (21° S, 55° E) between 2004 and 2016 using the SFIT4 algorithm: the retrieval strategy and the error budget are discussed. The trend of SF6 is analysed based on the FTIR retrievals at Reunion Island, the in situ measurements at America Samoa (SMO) and the collocated satellite measurements (MIPAS and ACE-FTS) in the southern tropics. The results show good agreement.
Annika Günther, Michael Höpfner, Björn-Martin Sinnhuber, Sabine Griessbach, Terry Deshler, Thomas von Clarmann, and Gabriele Stiller
Atmos. Chem. Phys., 18, 1217–1239, https://doi.org/10.5194/acp-18-1217-2018, https://doi.org/10.5194/acp-18-1217-2018, 2018
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Satellite-borne data of sulfur dioxide and a new data set of sulfate aerosol volume densities, as retrieved from MIPAS measurements, are studied in the upper-troposphere–lower-stratosphere region. General patterns of enhanced aerosol are in agreement with SO2. Via chemical transport model simulations for two volcanic eruptions in the Northern Hemisphere midlatitudes, we show that the volcanic enhancements in MIPAS SO2 and sulfate aerosol are consistent in terms of mass and transport patterns.
Miriam Sinnhuber, Uwe Berger, Bernd Funke, Holger Nieder, Thomas Reddmann, Gabriele Stiller, Stefan Versick, Thomas von Clarmann, and Jan Maik Wissing
Atmos. Chem. Phys., 18, 1115–1147, https://doi.org/10.5194/acp-18-1115-2018, https://doi.org/10.5194/acp-18-1115-2018, 2018
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Results from global models are used to analyze the impact of energetic particle precipitation on the middle atmosphere (10–80 km). Model results agree well with observations, and show strong enhancements of NOy, long-lasting ozone loss, and a net heating in the uppermost stratosphere (~35–45 km) during polar winter which changes sign in spring. Energetic particle precipitation therefore has the potential to impact atmospheric dynamics, starting from a warmer winter-time upper stratosphere.
Andreas Engel, Harald Bönisch, Jennifer Ostermöller, Martyn P. Chipperfield, Sandip Dhomse, and Patrick Jöckel
Atmos. Chem. Phys., 18, 601–619, https://doi.org/10.5194/acp-18-601-2018, https://doi.org/10.5194/acp-18-601-2018, 2018
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We present a new method to derive equivalent effective stratospheric chlorine (EESC), which is based on an improved formulation of the propagation of trends of species with chemical loss from the troposphere to the stratosphere. EESC calculated with the new method shows much better agreement with model-derived ESC. Based on this new formulation, we expect the halogen impact on midlatitude stratospheric ozone to return to 1980 values about 10 years later, then using the current formulation.
Gerald E. Nedoluha, Michael Kiefer, Stefan Lossow, R. Michael Gomez, Niklaus Kämpfer, Martin Lainer, Peter Forkman, Ole Martin Christensen, Jung Jin Oh, Paul Hartogh, John Anderson, Klaus Bramstedt, Bianca M. Dinelli, Maya Garcia-Comas, Mark Hervig, Donal Murtagh, Piera Raspollini, William G. Read, Karen Rosenlof, Gabriele P. Stiller, and Kaley A. Walker
Atmos. Chem. Phys., 17, 14543–14558, https://doi.org/10.5194/acp-17-14543-2017, https://doi.org/10.5194/acp-17-14543-2017, 2017
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As part of the second SPARC (Stratosphere–troposphere Processes And their Role in Climate) water vapor assessment (WAVAS-II), we present measurements taken from or coincident with seven sites from which ground-based microwave instruments measure water vapor in the middle atmosphere. In the lower mesosphere, we quantify instrumental differences in the observed trends and annual variations at six sites. We then present a range of observed trends in water vapor over the past 20 years.
Viktoria F. Sofieva, Erkki Kyrölä, Marko Laine, Johanna Tamminen, Doug Degenstein, Adam Bourassa, Chris Roth, Daniel Zawada, Mark Weber, Alexei Rozanov, Nabiz Rahpoe, Gabriele Stiller, Alexandra Laeng, Thomas von Clarmann, Kaley A. Walker, Patrick Sheese, Daan Hubert, Michel van Roozendael, Claus Zehner, Robert Damadeo, Joseph Zawodny, Natalya Kramarova, and Pawan K. Bhartia
Atmos. Chem. Phys., 17, 12533–12552, https://doi.org/10.5194/acp-17-12533-2017, https://doi.org/10.5194/acp-17-12533-2017, 2017
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We present a merged dataset of ozone profiles from several satellite instruments: SAGE II, GOMOS, SCIAMACHY, MIPAS, OSIRIS, ACE-FTS and OMPS. For merging, we used the latest versions of the original ozone datasets.
The merged SAGE–CCI–OMPS dataset is used for evaluating ozone trends in the stratosphere through multiple linear regression. Negative ozone trends in the upper stratosphere are observed before 1997 and positive trends are found after 1997.
David E. Oram, Matthew J. Ashfold, Johannes C. Laube, Lauren J. Gooch, Stephen Humphrey, William T. Sturges, Emma C. Leedham Elvidge, Grant L. Forster, Neil R. P. Harris, Mohammed Iqbal Mead, Azizan Abu Samah, Siew Moi Phang, Chang-Feng Ou-Yang, Neng-Huei Lin, Jia-Lin Wang, Angela K. Baker, Carl A. M. Brenninkmeijer, and David Sherry
Atmos. Chem. Phys., 17, 11929–11941, https://doi.org/10.5194/acp-17-11929-2017, https://doi.org/10.5194/acp-17-11929-2017, 2017
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We have observed large amounts of man-made chlorine compounds in E and SE Asia and in the upper tropical troposphere. These relatively short-lived compounds are not controlled by the Montreal Protocol, but if significant quantities were able to reach the stratosphere, the long-term recovery of stratospheric ozone would be delayed. We have also identified an important atmospheric transport mechanism that can rapidly transport these chemicals from E Asia to the upper troposphere via the tropics.
Stefan Lossow, Hella Garny, and Patrick Jöckel
Atmos. Chem. Phys., 17, 11521–11539, https://doi.org/10.5194/acp-17-11521-2017, https://doi.org/10.5194/acp-17-11521-2017, 2017
Roland Eichinger, Gary Shaffer, Nelson Albarrán, Maisa Rojas, and Fabrice Lambert
Geosci. Model Dev., 10, 3481–3498, https://doi.org/10.5194/gmd-10-3481-2017, https://doi.org/10.5194/gmd-10-3481-2017, 2017
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We reformulate the land biosphere of the reduced-complexity DCESS model by introducing three vegetation types and relating their latitudinal borders to global temperature change. This enhancement yields more realistic estimates of biosphere carbon cycling for cold conditions like the Last Glacial Maximum. As a first application we conduct transient simulations across the last glacial termination to estimate the importance of different processes on temperature, pCO2 and carbon isotope ratios.
Gabriele P. Stiller, Federico Fierli, Felix Ploeger, Chiara Cagnazzo, Bernd Funke, Florian J. Haenel, Thomas Reddmann, Martin Riese, and Thomas von Clarmann
Atmos. Chem. Phys., 17, 11177–11192, https://doi.org/10.5194/acp-17-11177-2017, https://doi.org/10.5194/acp-17-11177-2017, 2017
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The discrepancy between modelled and observed 25-year trends of the strength of the stratospheric Brewer–Dobson circulation (BDC) is still not resolved. With our paper we trace the observed hemispheric dipole structure of age of air trends back to natural variability in shorter-term (decadal) time frames. Beyond this we demonstrate that after correction for the decadal natural variability the remaining trend for the first decade of the 21st century is consistent with model simulations.
Wolfgang Steinbrecht, Lucien Froidevaux, Ryan Fuller, Ray Wang, John Anderson, Chris Roth, Adam Bourassa, Doug Degenstein, Robert Damadeo, Joe Zawodny, Stacey Frith, Richard McPeters, Pawan Bhartia, Jeannette Wild, Craig Long, Sean Davis, Karen Rosenlof, Viktoria Sofieva, Kaley Walker, Nabiz Rahpoe, Alexei Rozanov, Mark Weber, Alexandra Laeng, Thomas von Clarmann, Gabriele Stiller, Natalya Kramarova, Sophie Godin-Beekmann, Thierry Leblanc, Richard Querel, Daan Swart, Ian Boyd, Klemens Hocke, Niklaus Kämpfer, Eliane Maillard Barras, Lorena Moreira, Gerald Nedoluha, Corinne Vigouroux, Thomas Blumenstock, Matthias Schneider, Omaira García, Nicholas Jones, Emmanuel Mahieu, Dan Smale, Michael Kotkamp, John Robinson, Irina Petropavlovskikh, Neil Harris, Birgit Hassler, Daan Hubert, and Fiona Tummon
Atmos. Chem. Phys., 17, 10675–10690, https://doi.org/10.5194/acp-17-10675-2017, https://doi.org/10.5194/acp-17-10675-2017, 2017
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Thanks to the 1987 Montreal Protocol and its amendments, ozone-depleting chlorine (and bromine) in the stratosphere has declined slowly since the late 1990s. Improved and extended long-term ozone profile observations from satellites and ground-based stations confirm that ozone is responding as expected and has increased by about 2 % per decade since 2000 in the upper stratosphere, around 40 km altitude. At lower altitudes, however, ozone has not changed significantly since 2000.
Ellen Eckert, Thomas von Clarmann, Alexandra Laeng, Gabriele P. Stiller, Bernd Funke, Norbert Glatthor, Udo Grabowski, Sylvia Kellmann, Michael Kiefer, Andrea Linden, Arne Babenhauserheide, Gerald Wetzel, Christopher Boone, Andreas Engel, Jeremy J. Harrison, Patrick E. Sheese, Kaley A. Walker, and Peter F. Bernath
Atmos. Meas. Tech., 10, 2727–2743, https://doi.org/10.5194/amt-10-2727-2017, https://doi.org/10.5194/amt-10-2727-2017, 2017
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We retrieved vertical profiles of CCl4 from MIPAS Envisat IMK/IAA data. A detailed description of all characteristics is included in the paper as well as comparisons with historical measurements and comparisons with collocated measurements of instruments covering the same time span as MIPAS Envisat. A particular focus also lies on the usage of a new CCl4 spectroscopic dataset introduced recently, which leads to more realistic CCl4 volume mixing ratios.
Simone Dietmüller, Hella Garny, Felix Plöger, Patrick Jöckel, and Duy Cai
Atmos. Chem. Phys., 17, 7703–7719, https://doi.org/10.5194/acp-17-7703-2017, https://doi.org/10.5194/acp-17-7703-2017, 2017
Olivier Membrive, Cyril Crevoisier, Colm Sweeney, François Danis, Albert Hertzog, Andreas Engel, Harald Bönisch, and Laurence Picon
Atmos. Meas. Tech., 10, 2163–2181, https://doi.org/10.5194/amt-10-2163-2017, https://doi.org/10.5194/amt-10-2163-2017, 2017
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A new high-resolution AirCore system is presented. This system flown with stratospheric balloons allows us to sample atmospheric air during the descent. The analysis of trace gases (CO2 and CH4 in this case) in the collected air sample provides information on the vertical distribution along the atmospheric column. The continuous vertical profiles retrieved may contribute to several research topics concerning the observation of greenhouse gases and, more generally, carbon cycle studies.
Andreas Engel, Harald Bönisch, Markus Ullrich, Robert Sitals, Olivier Membrive, Francois Danis, and Cyril Crevoisier
Atmos. Chem. Phys., 17, 6825–6838, https://doi.org/10.5194/acp-17-6825-2017, https://doi.org/10.5194/acp-17-6825-2017, 2017
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AirCore is new technique for sampling stratospheric air. We present new observations of CO2 and CH4 using AirCore and derive stratospheric transport time, called the mean age of air. The purpose of using AirCore is to provide a cost-effective tool for deriving mean age. Mean age may serve as a proxy to investigate changes in stratospheric circulation. We show that there is no statistically significant trend in our 40-year time series of mean age, which is now extended using AirCore.
Robert L. Herman, Eric A. Ray, Karen H. Rosenlof, Kristopher M. Bedka, Michael J. Schwartz, William G. Read, Robert F. Troy, Keith Chin, Lance E. Christensen, Dejian Fu, Robert A. Stachnik, T. Paul Bui, and Jonathan M. Dean-Day
Atmos. Chem. Phys., 17, 6113–6124, https://doi.org/10.5194/acp-17-6113-2017, https://doi.org/10.5194/acp-17-6113-2017, 2017
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This study reports new aircraft field observations of elevated water vapor greater than 10 ppmv in the overworld stratosphere over the summertime continental US. Back trajectories from the flight track intersect overshooting convective tops within the previous 1 to 7 days, suggesting that ice is convectively and irreversibly transported to the stratosphere in the most energetic overshooting convective events. Satellite measurements (Aura MLS) indicate that such events are uncommon (< 1 %).
Alexandra Laeng, Thomas von Clarmann, Gabriele Stiller, Bianca Maria Dinelli, Anu Dudhia, Piera Raspollini, Norbert Glatthor, Udo Grabowski, Viktoria Sofieva, Lucien Froidevaux, Kaley A. Walker, and Claus Zehner
Atmos. Meas. Tech., 10, 1511–1518, https://doi.org/10.5194/amt-10-1511-2017, https://doi.org/10.5194/amt-10-1511-2017, 2017
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A MIPAS instrument was flown in 2002–2012 on the Envisat satellite and measured atmospheric composition. There exist four processors retrieving atmospheric profiles from MIPAS spectra. We performed a mathematically clean merging of 2007–2008 datasets of ozone from these four processors. The merged product was compared with ozone datasets from ACE-FTS and MLS instruments. The advantages and the shortcomings of this merged product are discussed.
Mohamadou Diallo, Bernard Legras, Eric Ray, Andreas Engel, and Juan A. Añel
Atmos. Chem. Phys., 17, 3861–3878, https://doi.org/10.5194/acp-17-3861-2017, https://doi.org/10.5194/acp-17-3861-2017, 2017
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We construct a new monthly zonal mean CO2 distribution from the upper troposphere to the stratosphere over the 2000–2010 period. The main features of the CO2 distribution are consistent with expected variability due to the transport of long-lived trace gases by the Brewer–Dobson circulation. The method used to construct this CO2 product is unique and should be useful for model and satellite validation in the upper troposphere and stratosphere.
Jennifer Ostermöller, Harald Bönisch, Patrick Jöckel, and Andreas Engel
Atmos. Chem. Phys., 17, 3785–3797, https://doi.org/10.5194/acp-17-3785-2017, https://doi.org/10.5194/acp-17-3785-2017, 2017
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We analysed the temporal evolution of fractional release factors (FRFs) from EMAC model simulations for several halocarbons and nitrous oxide. The current formulation of FRFs yields values that depend on the tropospheric trend of the species. This is a problematic issue for the application of FRF in the calculation of steady-state quantities (e.g. ODP). Including a loss term in the calculation, we develop a new formulation of FRF and find that the time dependence can almost be compensated.
Stefan Lossow, Farahnaz Khosrawi, Gerald E. Nedoluha, Faiza Azam, Klaus Bramstedt, John. P. Burrows, Bianca M. Dinelli, Patrick Eriksson, Patrick J. Espy, Maya García-Comas, John C. Gille, Michael Kiefer, Stefan Noël, Piera Raspollini, William G. Read, Karen H. Rosenlof, Alexei Rozanov, Christopher E. Sioris, Gabriele P. Stiller, Kaley A. Walker, and Katja Weigel
Atmos. Meas. Tech., 10, 1111–1137, https://doi.org/10.5194/amt-10-1111-2017, https://doi.org/10.5194/amt-10-1111-2017, 2017
Bernd Funke, William Ball, Stefan Bender, Angela Gardini, V. Lynn Harvey, Alyn Lambert, Manuel López-Puertas, Daniel R. Marsh, Katharina Meraner, Holger Nieder, Sanna-Mari Päivärinta, Kristell Pérot, Cora E. Randall, Thomas Reddmann, Eugene Rozanov, Hauke Schmidt, Annika Seppälä, Miriam Sinnhuber, Timofei Sukhodolov, Gabriele P. Stiller, Natalia D. Tsvetkova, Pekka T. Verronen, Stefan Versick, Thomas von Clarmann, Kaley A. Walker, and Vladimir Yushkov
Atmos. Chem. Phys., 17, 3573–3604, https://doi.org/10.5194/acp-17-3573-2017, https://doi.org/10.5194/acp-17-3573-2017, 2017
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Simulations from eight atmospheric models have been compared to tracer and temperature observations from seven satellite instruments in order to evaluate the energetic particle indirect effect (EPP IE) during the perturbed northern hemispheric (NH) winter 2008/2009. Models are capable to reproduce the EPP IE in dynamically and geomagnetically quiescent NH winter conditions. The results emphasize the need for model improvements in the dynamical representation of elevated stratopause events.
Norbert Glatthor, Michael Höpfner, Adrian Leyser, Gabriele P. Stiller, Thomas von Clarmann, Udo Grabowski, Sylvia Kellmann, Andrea Linden, Björn-Martin Sinnhuber, Gisèle Krysztofiak, and Kaley A. Walker
Atmos. Chem. Phys., 17, 2631–2652, https://doi.org/10.5194/acp-17-2631-2017, https://doi.org/10.5194/acp-17-2631-2017, 2017
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To date, information on the global distribution of atmospheric carbonyl sulfide (OCS) is still rather sparse.
However, detailed knowledge of the OCS distribution is of scientific interest, because this trace gas is on one of the major sources of atmospheric sulfur, which is a prerequisite of the stratospheric aerosol layer. Under this aspect we present a comprehensive space-borne data set of global OCS concentrations covering the period from June 2002 to April 2012.
Garlich Fischbeck, Harald Bönisch, Marco Neumaier, Carl A. M. Brenninkmeijer, Johannes Orphal, Joel Brito, Julia Becker, Detlev Sprung, Peter F. J. van Velthoven, and Andreas Zahn
Atmos. Chem. Phys., 17, 1985–2008, https://doi.org/10.5194/acp-17-1985-2017, https://doi.org/10.5194/acp-17-1985-2017, 2017
Tamás Kovács, Wuhu Feng, Anna Totterdill, John M. C. Plane, Sandip Dhomse, Juan Carlos Gómez-Martín, Gabriele P. Stiller, Florian J. Haenel, Christopher Smith, Piers M. Forster, Rolando R. García, Daniel R. Marsh, and Martyn P. Chipperfield
Atmos. Chem. Phys., 17, 883–898, https://doi.org/10.5194/acp-17-883-2017, https://doi.org/10.5194/acp-17-883-2017, 2017
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Sulfur hexafluoride (SF6) is a very potent greenhouse gas, which is present in the atmosphere only through its industrial use, for example as an electrical insulator. To estimate accurately the impact of SF6 emissions on climate we need to know how long it persists in the atmosphere before being removed. Previous estimates of the SF6 lifetime indicate a large degree of uncertainty. Here we use a detailed atmospheric model to calculate a current best estimate of the SF6 lifetime.
Á. Aythami Jurado-Navarro, Manuel López-Puertas, Bernd Funke, Maya García-Comas, Angela Gardini, Francisco González-Galindo, Gabriele P. Stiller, Thomas von Clarmann, Udo Grabowski, and Andrea Linden
Atmos. Meas. Tech., 9, 6081–6100, https://doi.org/10.5194/amt-9-6081-2016, https://doi.org/10.5194/amt-9-6081-2016, 2016
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We present global distributions of CO2 concentrations in the upper atmosphere (70–140 km) derived from high-resolution 4.3 µm MIPAS spectra from 2005 to 2012. CO2 relative abundances have been measured at 120–140 km for the first time. The data have an unprecedented accuracy. CO2 shows a strong seasonal behaviour. CO2 largely controls the temperature of the upper atmosphere and its measurement is very important for understanding the impact of climate change in this region.
Bastiaan Jonkheid, Thomas Röckmann, Norbert Glatthor, Christof Janssen, Gabriele Stiller, and Thomas von Clarmann
Atmos. Meas. Tech., 9, 6069–6079, https://doi.org/10.5194/amt-9-6069-2016, https://doi.org/10.5194/amt-9-6069-2016, 2016
Bärbel Vogel, Gebhard Günther, Rolf Müller, Jens-Uwe Grooß, Armin Afchine, Heiko Bozem, Peter Hoor, Martina Krämer, Stefan Müller, Martin Riese, Christian Rolf, Nicole Spelten, Gabriele P. Stiller, Jörn Ungermann, and Andreas Zahn
Atmos. Chem. Phys., 16, 15301–15325, https://doi.org/10.5194/acp-16-15301-2016, https://doi.org/10.5194/acp-16-15301-2016, 2016
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The identification of transport pathways from the Asian monsoon anticyclone into the lower stratosphere is unclear. Global simulations with the CLaMS model demonstrate that source regions in Asia and in the Pacific Ocean have a significant impact on the chemical composition of the lower stratosphere of the Northern Hemisphere by flooding the extratropical lower stratosphere with young moist air masses. Two main horizontal transport pathways from the Asian monsoon anticyclone are identified.
Johannes C. Laube, Norfazrin Mohd Hanif, Patricia Martinerie, Eileen Gallacher, Paul J. Fraser, Ray Langenfelds, Carl A. M. Brenninkmeijer, Jakob Schwander, Emmanuel Witrant, Jia-Lin Wang, Chang-Feng Ou-Yang, Lauren J. Gooch, Claire E. Reeves, William T. Sturges, and David E. Oram
Atmos. Chem. Phys., 16, 15347–15358, https://doi.org/10.5194/acp-16-15347-2016, https://doi.org/10.5194/acp-16-15347-2016, 2016
Matthias Nützel, Martin Dameris, and Hella Garny
Atmos. Chem. Phys., 16, 14755–14774, https://doi.org/10.5194/acp-16-14755-2016, https://doi.org/10.5194/acp-16-14755-2016, 2016
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Using seven reanalyses, we study the movement and drivers of the upper tropospheric–lower stratospheric anticyclone (AC) that forms during the Asian summer monsoon and is debated to be an important pathway for air masses to the stratosphere. We find that the distribution of the AC's centre position, and especially the so-called bimodality, largely depends on the reanalysis. Furthermore, we can connect shifts of the AC to precipitation and convection anomalies over India and the western Pacific.
Michael Höpfner, Rainer Volkamer, Udo Grabowski, Michel Grutter, Johannes Orphal, Gabriele Stiller, Thomas von Clarmann, and Gerald Wetzel
Atmos. Chem. Phys., 16, 14357–14369, https://doi.org/10.5194/acp-16-14357-2016, https://doi.org/10.5194/acp-16-14357-2016, 2016
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Ammonia (NH3) in the atmosphere is important because of its influence on aerosol and cloud formation and its increasing anthropogenic emissions. We report the first detection of NH3 in the upper troposphere by the analysis of infrared limb emission spectra measured by the MIPAS instrument on Envisat. We have found enhanced values of NH3 within the Asian summer monsoon upper troposphere, where it might contribute to the composition of the Asian tropopause aerosol layer.
Florian Obersteiner, Harald Bönisch, Timo Keber, Simon O'Doherty, and Andreas Engel
Atmos. Meas. Tech., 9, 5265–5279, https://doi.org/10.5194/amt-9-5265-2016, https://doi.org/10.5194/amt-9-5265-2016, 2016
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The analysis of trace gases in ambient air requires a preconcentration technique, in many cases to make the species of interest detectable and quantifiable. In this paper, such a preconcentration set-up is presented. Target species are trapped on adsorptive material cooled by a Stirling cooler which allows for a very low adsorption temperature but only requires electrical power. A simple and lightweight mechanical design guarantees very good suitability for remote-site field operation.
Duy Cai, Martin Dameris, Hella Garny, Felix Bunzel, Patrick Jöckel, and Phoebe Graf
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2016-870, https://doi.org/10.5194/acp-2016-870, 2016
Revised manuscript not accepted
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Reliable information on weather and climate are of increasing interest for economy, politics and society.
In particular decadal timescales become more and more important. This study focuses on stratospheric processes relevant for the dynamical variability on intra decadal timescale. We apply a so called power spectra analysis. With this method and further analyses we could determine a minimum vertical resolution for numerical models, which is required to capture these processes.
Andreas Ostler, Ralf Sussmann, Prabir K. Patra, Sander Houweling, Marko De Bruine, Gabriele P. Stiller, Florian J. Haenel, Johannes Plieninger, Philippe Bousquet, Yi Yin, Marielle Saunois, Kaley A. Walker, Nicholas M. Deutscher, David W. T. Griffith, Thomas Blumenstock, Frank Hase, Thorsten Warneke, Zhiting Wang, Rigel Kivi, and John Robinson
Atmos. Meas. Tech., 9, 4843–4859, https://doi.org/10.5194/amt-9-4843-2016, https://doi.org/10.5194/amt-9-4843-2016, 2016
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Our evaluation of column-averaged methane (XCH4) in models and TCCON reveals latitudinal biases between 0.4 % and 2.1 % originating from an inter-model spread in stratospheric CH4. Substituting model stratospheric CH4 fields by satellite data significantly reduces the large XCH4 bias observed for one model. For other models, showing only minor biases, the impact is ambiguous; i.e., the satellite uncertainty range hinders a more accurate model evaluation needed to improve inverse modeling.
Cathy M. Trudinger, Paul J. Fraser, David M. Etheridge, William T. Sturges, Martin K. Vollmer, Matt Rigby, Patricia Martinerie, Jens Mühle, David R. Worton, Paul B. Krummel, L. Paul Steele, Benjamin R. Miller, Johannes Laube, Francis S. Mani, Peter J. Rayner, Christina M. Harth, Emmanuel Witrant, Thomas Blunier, Jakob Schwander, Simon O'Doherty, and Mark Battle
Atmos. Chem. Phys., 16, 11733–11754, https://doi.org/10.5194/acp-16-11733-2016, https://doi.org/10.5194/acp-16-11733-2016, 2016
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Perfluorocarbons (PFCs) are potent, long-lived and mostly man-made greenhouse gases released to the atmosphere mainly during aluminium production and semiconductor manufacture. Here we present the first continuous histories of three PFCs from 1800 to 2014, derived from measurements of these PFCs in the atmosphere and in air bubbles in polar ice. The records show how human actions have affected these important greenhouse gases over the past century.
Stefan Müller, Peter Hoor, Heiko Bozem, Ellen Gute, Bärbel Vogel, Andreas Zahn, Harald Bönisch, Timo Keber, Martina Krämer, Christian Rolf, Martin Riese, Hans Schlager, and Andreas Engel
Atmos. Chem. Phys., 16, 10573–10589, https://doi.org/10.5194/acp-16-10573-2016, https://doi.org/10.5194/acp-16-10573-2016, 2016
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In situ airborne measurements performed during TACTS/ESMVal 2012 were analysed to investigate the chemical compostion of the upper troposphere and lower stratosphere. N2O, CO and O3 data show an increase in tropospherically affected air masses within the extratropical stratosphere from August to September 2012, which originate from the Asian monsoon region. Thus, the Asian monsoon anticyclone significantly affected the chemical composition of the extratropical stratosphere during summer 2012.
E. Eckert, A. Laeng, S. Lossow, S. Kellmann, G. Stiller, T. von Clarmann, N. Glatthor, M. Höpfner, M. Kiefer, H. Oelhaf, J. Orphal, B. Funke, U. Grabowski, F. Haenel, A. Linden, G. Wetzel, W. Woiwode, P. F. Bernath, C. Boone, G. S. Dutton, J. W. Elkins, A. Engel, J. C. Gille, F. Kolonjari, T. Sugita, G. C. Toon, and K. A. Walker
Atmos. Meas. Tech., 9, 3355–3389, https://doi.org/10.5194/amt-9-3355-2016, https://doi.org/10.5194/amt-9-3355-2016, 2016
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We investigate the accuracy, precision and long-term stability of the MIPAS Envisat IMK/IAA CFC-11 (CCl3F) and CFC-12 (CCl2F2) products.
For comparisons we use several data products from satellite, airplane and balloon-borne instruments as well as ground-based data.
MIPAS Envisat CFC-11 has a slight high bias at the lower end of the profile.
CFC-12 agrees well with other data products.
The temporal stability is good up to ~ 30 km, but still leaves room for improvement.
R. Hossaini, P. K. Patra, A. A. Leeson, G. Krysztofiak, N. L. Abraham, S. J. Andrews, A. T. Archibald, J. Aschmann, E. L. Atlas, D. A. Belikov, H. Bönisch, L. J. Carpenter, S. Dhomse, M. Dorf, A. Engel, W. Feng, S. Fuhlbrügge, P. T. Griffiths, N. R. P. Harris, R. Hommel, T. Keber, K. Krüger, S. T. Lennartz, S. Maksyutov, H. Mantle, G. P. Mills, B. Miller, S. A. Montzka, F. Moore, M. A. Navarro, D. E. Oram, K. Pfeilsticker, J. A. Pyle, B. Quack, A. D. Robinson, E. Saikawa, A. Saiz-Lopez, S. Sala, B.-M. Sinnhuber, S. Taguchi, S. Tegtmeier, R. T. Lidster, C. Wilson, and F. Ziska
Atmos. Chem. Phys., 16, 9163–9187, https://doi.org/10.5194/acp-16-9163-2016, https://doi.org/10.5194/acp-16-9163-2016, 2016
Markus Kunze, Peter Braesicke, Ulrike Langematz, and Gabriele Stiller
Atmos. Chem. Phys., 16, 8695–8714, https://doi.org/10.5194/acp-16-8695-2016, https://doi.org/10.5194/acp-16-8695-2016, 2016
Bernd Funke, Manuel López-Puertas, Gabriele P. Stiller, Stefan Versick, and Thomas von Clarmann
Atmos. Chem. Phys., 16, 8667–8693, https://doi.org/10.5194/acp-16-8667-2016, https://doi.org/10.5194/acp-16-8667-2016, 2016
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We present a semi-empirical model for the reconstruction of polar winter descent of reactive nitrogen (NOy) produced by energetic particle precipitation (EPP) into the stratosphere. It can be used to prescribe NOy in chemistry climate models with an upper lid below the EPP source region. We also found a significant reduction of the EPP-generated NOy during the last 30 years, likely affecting the long-term NOy trend by counteracting the expected increase caused by growing N2O emission.
Sabine Brinkop, Martin Dameris, Patrick Jöckel, Hella Garny, Stefan Lossow, and Gabriele Stiller
Atmos. Chem. Phys., 16, 8125–8140, https://doi.org/10.5194/acp-16-8125-2016, https://doi.org/10.5194/acp-16-8125-2016, 2016
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This study investigates the water vapour decline in the stratosphere beginning in the year 2000 and other similarly strong stratospheric water vapour reductions. The driving forces are tropical sea surface temperature (SST) changes due to coincidence with a preceding ENSO event and supported by the west to east change of the QBO.
There are indications that both SSTs and the specific dynamical state of the atmosphere contribute to the long period of low water vapour values from 2001 to 2006.
Maya García-Comas, Manuel López-Puertas, Bernd Funke, Á. Aythami Jurado-Navarro, Angela Gardini, Gabriele P. Stiller, Thomas von Clarmann, and Michael Höpfner
Atmos. Chem. Phys., 16, 6701–6719, https://doi.org/10.5194/acp-16-6701-2016, https://doi.org/10.5194/acp-16-6701-2016, 2016
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We have analysed IR measurements of PMCs in the NH and SH from 2005 to 2012. This technique is sensitive to the total ice volume independent of particle size. For the first time, we have measured the total ice volume from the midlatitudes to the poles. The data indicate a layer of ice from 81 to 89 km and from the poles to 50–60º in each hemisphere, increasing near the poles. The ice density is larger in the NH than in the SH and located 1 km lower. PMCs also show a diurnal variation.
Patrick Jöckel, Holger Tost, Andrea Pozzer, Markus Kunze, Oliver Kirner, Carl A. M. Brenninkmeijer, Sabine Brinkop, Duy S. Cai, Christoph Dyroff, Johannes Eckstein, Franziska Frank, Hella Garny, Klaus-Dirk Gottschaldt, Phoebe Graf, Volker Grewe, Astrid Kerkweg, Bastian Kern, Sigrun Matthes, Mariano Mertens, Stefanie Meul, Marco Neumaier, Matthias Nützel, Sophie Oberländer-Hayn, Roland Ruhnke, Theresa Runde, Rolf Sander, Dieter Scharffe, and Andreas Zahn
Geosci. Model Dev., 9, 1153–1200, https://doi.org/10.5194/gmd-9-1153-2016, https://doi.org/10.5194/gmd-9-1153-2016, 2016
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With an advanced numerical global chemistry climate model (CCM) we performed several detailed
combined hind-cast and projection simulations of the period 1950 to 2100 to assess the
past, present, and potential future dynamical and chemical state of the Earth atmosphere.
The manuscript documents the model and the various applied model set-ups and provides
a first evaluation of the simulation results from a global perspective as a quality check of the data.
M. Chirkov, G. P. Stiller, A. Laeng, S. Kellmann, T. von Clarmann, C. D. Boone, J. W. Elkins, A. Engel, N. Glatthor, U. Grabowski, C. M. Harth, M. Kiefer, F. Kolonjari, P. B. Krummel, A. Linden, C. R. Lunder, B. R. Miller, S. A. Montzka, J. Mühle, S. O'Doherty, J. Orphal, R. G. Prinn, G. Toon, M. K. Vollmer, K. A. Walker, R. F. Weiss, A. Wiegele, and D. Young
Atmos. Chem. Phys., 16, 3345–3368, https://doi.org/10.5194/acp-16-3345-2016, https://doi.org/10.5194/acp-16-3345-2016, 2016
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HCFC-22 global distributions from MIPAS measurements for 2005 to 2012 are presented. Tropospheric trends are in good agreement with ground-based observations. A layer of enhanced HCFC-22 in the upper tropospheric tropics and northern subtropics is identified to come from Asian sources uplifted in the Asian monsoon. Stratospheric distributions provide show seasonal, semi-annual, and QBO-related variations. Hemispheric asymmetries of trends hint towards a change in the stratospheric circulation.
Andreas Engel, Harald Bönisch, Tim Schwarzenberger, Hans-Peter Haase, Katja Grunow, Jana Abalichin, and Stephan Sala
Atmos. Meas. Tech., 9, 1051–1062, https://doi.org/10.5194/amt-9-1051-2016, https://doi.org/10.5194/amt-9-1051-2016, 2016
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We present a validation of MIPAS-ENVISAT vertical profiles (ESA operational retrieval version 6.0) of N2O, CH4, CFC-12, and CFC-11. The geophysical validation is performed using data from a balloon-borne cryogenic whole air sampler and trajectory matching. We show that the validation results are different for the period prior to 2005 compared to the post 2005 period. N2O, CH4, and CFC-12 show partly good agreement while CFC-11 data from this retrieval cannot be used for scientific studies.
Hella Garny and William J. Randel
Atmos. Chem. Phys., 16, 2703–2718, https://doi.org/10.5194/acp-16-2703-2016, https://doi.org/10.5194/acp-16-2703-2016, 2016
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We investigate the fate of air that originates in the monsoon region in the upper troposphere, where it was transported to by convection. We find that almost half of the air parcels released in the monsoon region in the upper troposphere reach the stratosphere within 60 days, and most ascend to the tropical lower stratosphere. This suggests that trace gases, including pollutants, that are transported into the stratosphere via the Asian monsoon are in a position to enter the deep stratosphere.
Johannes Plieninger, Alexandra Laeng, Stefan Lossow, Thomas von Clarmann, Gabriele P. Stiller, Sylvia Kellmann, Andrea Linden, Michael Kiefer, Kaley A. Walker, Stefan Noël, Mark E. Hervig, Martin McHugh, Alyn Lambert, Joachim Urban, James W. Elkins, and Donal Murtagh
Atmos. Meas. Tech., 9, 765–779, https://doi.org/10.5194/amt-9-765-2016, https://doi.org/10.5194/amt-9-765-2016, 2016
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We compare concentration profiles of methane and nitrous oxide measured from MIPAS-ENVISAT and derived with a new retrieval setup to those measured by other satellite instruments and to surface measurements. For methane we use profiles measured by ACE-FTS, HALOE and SCIAMACHY; for nitrous oxide we use profiles measured by ACE-FTS, Aura-MLS and Odin-SMR for the comparisons. We give a quantitative bias estimation and compare the estimated errors provided by the instruments.
F. Obersteiner, H. Bönisch, and A. Engel
Atmos. Meas. Tech., 9, 179–194, https://doi.org/10.5194/amt-9-179-2016, https://doi.org/10.5194/amt-9-179-2016, 2016
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We present the characterization and application of a new gas chromatography time-of-flight mass spectrometry instrument, with focus on quantitative analysis of halocarbons in air samples. The applicability of the TOFMS technique, e.g. to form the basis of a "digital air archieve", is supported by the findings of this work: very high sensitivity, high measurement precision, a large dynamical range and an open data format which allows in-depth analysis of the data.
K. Weigel, A. Rozanov, F. Azam, K. Bramstedt, R. Damadeo, K.-U. Eichmann, C. Gebhardt, D. Hurst, M. Kraemer, S. Lossow, W. Read, N. Spelten, G. P. Stiller, K. A. Walker, M. Weber, H. Bovensmann, and J. P. Burrows
Atmos. Meas. Tech., 9, 133–158, https://doi.org/10.5194/amt-9-133-2016, https://doi.org/10.5194/amt-9-133-2016, 2016
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The SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY) aboard the Envisat satellite provided measurements between 2002 and 2012 with different viewing geometries. The limb viewing geometry allows the retrieval of water vapour profiles in the UTLS (upper troposphere and lower stratosphere) from the near-infrared spectral range (1353–1410 nm). Here, we present data version 3.01 and compare it to other water vapour data.
Roland Eichinger, Gary Shaffer, Nelson Albarrán, Maisa Rojas, and Fabrice Lambert
Clim. Past Discuss., https://doi.org/10.5194/cp-2015-190, https://doi.org/10.5194/cp-2015-190, 2016
Revised manuscript not accepted
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We apply the DCESS ESM to assess the process of Southern Ocean deep water upwelling as to whether it can explain the climate change between 17.5 and 14.5 kaBP. From a glacial climate state, which was generated under the guidance of proxy data records, transient climate simulations are conducted to analyse the impact of various parameters. This approach can explain parts but not all of the observed atmospheric variations in temperatures, carbon dioxide and carbon isotopes across that period.
F. Khosrawi, J. Urban, S. Lossow, G. Stiller, K. Weigel, P. Braesicke, M. C. Pitts, A. Rozanov, J. P. Burrows, and D. Murtagh
Atmos. Chem. Phys., 16, 101–121, https://doi.org/10.5194/acp-16-101-2016, https://doi.org/10.5194/acp-16-101-2016, 2016
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Our sensitivity studies based on air parcel trajectories confirm that Polar stratospheric cloud (PSC) formation is quite sensitive to water vapour and temperature changes. Considering water vapour time series from satellite measurements we do not find a consistent, significant trend in water vapour in the lower stratosphere during the past 15 years (2000–2014). Thus, the severe dentrification observed in 2010/2011 cannot be directly related to increases in stratospheric water vapour.
A. Laeng, J. Plieninger, T. von Clarmann, U. Grabowski, G. Stiller, E. Eckert, N. Glatthor, F. Haenel, S. Kellmann, M. Kiefer, A. Linden, S. Lossow, L. Deaver, A. Engel, M. Hervig, I. Levin, M. McHugh, S. Noël, G. Toon, and K. Walker
Atmos. Meas. Tech., 8, 5251–5261, https://doi.org/10.5194/amt-8-5251-2015, https://doi.org/10.5194/amt-8-5251-2015, 2015
F. J. Haenel, G. P. Stiller, T. von Clarmann, B. Funke, E. Eckert, N. Glatthor, U. Grabowski, S. Kellmann, M. Kiefer, A. Linden, and T. Reddmann
Atmos. Chem. Phys., 15, 13161–13176, https://doi.org/10.5194/acp-15-13161-2015, https://doi.org/10.5194/acp-15-13161-2015, 2015
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Stratospheric circulation is thought to change as a consequence of climate change. Empirical evidence, however, is sparse. In this paper we present latitude- and altitude-resolved trends of the mean age of stratospheric air as derived from SF6 measurements performed by the MIPAS satellite instrument. The mean of the age of stratospheric air is a measure of the intensity of the Brewer-Dobson circulation. In this paper we discuss differences with respect to a preceding analysis by Stiller et al.
J. Plieninger, T. von Clarmann, G. P. Stiller, U. Grabowski, N. Glatthor, S. Kellmann, A. Linden, F. Haenel, M. Kiefer, M. Höpfner, A. Laeng, and S. Lossow
Atmos. Meas. Tech., 8, 4657–4670, https://doi.org/10.5194/amt-8-4657-2015, https://doi.org/10.5194/amt-8-4657-2015, 2015
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We present our revised CH4 and N2O profiles derived from MIPAS-ENVISAT spectra, which are now available for the entire measurement period. We describe the retrieval of the profiles and discuss the improvements compared to earlier versions and their effect on the mixing ratios. We analyse the averaging kernels and the resolution of the profiles. An error discussion for both gases is given.
S. T. Lennartz, G. Krysztofiak, C. A. Marandino, B.-M. Sinnhuber, S. Tegtmeier, F. Ziska, R. Hossaini, K. Krüger, S. A. Montzka, E. Atlas, D. E. Oram, T. Keber, H. Bönisch, and B. Quack
Atmos. Chem. Phys., 15, 11753–11772, https://doi.org/10.5194/acp-15-11753-2015, https://doi.org/10.5194/acp-15-11753-2015, 2015
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Marine-produced short-lived trace gases such as halocarbons and DMS significantly impact atmospheric chemistry. To assess this impact on ozone depletion and the radiative budget, it is critical that their marine emissions in atmospheric chemistry models are quantified as accurately as possible. We show that calculating emissions online with an interactive atmosphere improves the agreement with current observations and should be employed regularly in models where marine sources are important.
N. Rahpoe, M. Weber, A. V. Rozanov, K. Weigel, H. Bovensmann, J. P. Burrows, A. Laeng, G. Stiller, T. von Clarmann, E. Kyrölä, V. F. Sofieva, J. Tamminen, K. Walker, D. Degenstein, A. E. Bourassa, R. Hargreaves, P. Bernath, J. Urban, and D. P. Murtagh
Atmos. Meas. Tech., 8, 4369–4381, https://doi.org/10.5194/amt-8-4369-2015, https://doi.org/10.5194/amt-8-4369-2015, 2015
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The analyses among six satellite instruments measuring ozone reveals that the relative drift between the sensors is not significant in the stratosphere and we conclude that merging of data from these instruments is possible. The merged ozone profiles can then be ingested in global climate models for long-term forecasts of ozone and climate change in the atmosphere. The added drift uncertainty is estimated at about 3% per decade (1 sigma) and should be applied in the calculation of ozone trends.
S. Bender, M. Sinnhuber, T. von Clarmann, G. Stiller, B. Funke, M. López-Puertas, J. Urban, K. Pérot, K. A. Walker, and J. P. Burrows
Atmos. Meas. Tech., 8, 4171–4195, https://doi.org/10.5194/amt-8-4171-2015, https://doi.org/10.5194/amt-8-4171-2015, 2015
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We compare the nitric oxide (NO) daily zonal mean number density data sets in the mesosphere and lower thermosphere (MLT, 60km to 150km) from four instruments: ACE-FTS (2004--2010), MIPAS (2005--2012), SCIAMACHY (2008--2012), and SMR (2003--2012). We find that these data sets from different instruments consistently constrain NO in the MLT. Thus, they offer reliable forcing inputs for climate and chemistry climate models as an initial step to include solar and geomagnetic activity.
T. Schieferdecker, S. Lossow, G. P. Stiller, and T. von Clarmann
Atmos. Chem. Phys., 15, 9851–9863, https://doi.org/10.5194/acp-15-9851-2015, https://doi.org/10.5194/acp-15-9851-2015, 2015
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A merged data set of HALOE and MIPAS lower stratospheric water vapour has been constructed. Multivariate linear regression shows that the merged time series can best be explained if a proxy for the 11-year solar cycle is considered. The amplitude of the solar cycle signal in water vapour is slightly higher than that which can be explained by the known solar cycle variation of cold-point temperatures.
R. Eichinger, P. Jöckel, and S. Lossow
Atmos. Chem. Phys., 15, 7003–7015, https://doi.org/10.5194/acp-15-7003-2015, https://doi.org/10.5194/acp-15-7003-2015, 2015
M. Höpfner, C. D. Boone, B. Funke, N. Glatthor, U. Grabowski, A. Günther, S. Kellmann, M. Kiefer, A. Linden, S. Lossow, H. C. Pumphrey, W. G. Read, A. Roiger, G. Stiller, H. Schlager, T. von Clarmann, and K. Wissmüller
Atmos. Chem. Phys., 15, 7017–7037, https://doi.org/10.5194/acp-15-7017-2015, https://doi.org/10.5194/acp-15-7017-2015, 2015
S. J. Allin, J. C. Laube, E. Witrant, J. Kaiser, E. McKenna, P. Dennis, R. Mulvaney, E. Capron, P. Martinerie, T. Röckmann, T. Blunier, J. Schwander, P. J. Fraser, R. L. Langenfelds, and W. T. Sturges
Atmos. Chem. Phys., 15, 6867–6877, https://doi.org/10.5194/acp-15-6867-2015, https://doi.org/10.5194/acp-15-6867-2015, 2015
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Stratospheric ozone protects life on Earth from harmful UV-B radiation. Chlorofluorocarbons (CFCs) are man-made compounds which act to destroy this barrier.
This paper presents (1) the first measurements of the stratospheric δ(37Cl) of CFCs -11 and -113; (2) the first quantification of long-term trends in the tropospheric δ(37Cl) of CFCs -11, -12 and -113.
This study provides a better understanding of source and sink processes associated with these destructive compounds.
L. E. Revell, F. Tummon, A. Stenke, T. Sukhodolov, A. Coulon, E. Rozanov, H. Garny, V. Grewe, and T. Peter
Atmos. Chem. Phys., 15, 5887–5902, https://doi.org/10.5194/acp-15-5887-2015, https://doi.org/10.5194/acp-15-5887-2015, 2015
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We have examined the effects of ozone precursor emissions and climate change on the tropospheric ozone budget. Under RCP 6.0, ozone in the future is governed primarily by changes in nitrogen oxides (NOx). Methane is also important, and induces an increase in tropospheric ozone that is approximately one-third of that caused by NOx. This study highlights the critical role that emission policies globally have to play in determining tropospheric ozone evolution through the 21st century.
J. Hoker, F. Obersteiner, H. Bönisch, and A. Engel
Atmos. Meas. Tech., 8, 2195–2206, https://doi.org/10.5194/amt-8-2195-2015, https://doi.org/10.5194/amt-8-2195-2015, 2015
R. Eichinger, P. Jöckel, S. Brinkop, M. Werner, and S. Lossow
Atmos. Chem. Phys., 15, 5537–5555, https://doi.org/10.5194/acp-15-5537-2015, https://doi.org/10.5194/acp-15-5537-2015, 2015
T. Fytterer, M. G. Mlynczak, H. Nieder, K. Pérot, M. Sinnhuber, G. Stiller, and J. Urban
Atmos. Chem. Phys., 15, 3327–3338, https://doi.org/10.5194/acp-15-3327-2015, https://doi.org/10.5194/acp-15-3327-2015, 2015
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Energetic particles from the sun produce NOx (=N+NO+NO2) in the mesosphere/lower thermosphere. The NOx can be transported downward in the stratosphere during polar winter where NOx eventually depletes O3. This entire chain is the so-called energetic particle precipitation (EPP) indirect effect.
Here we show downward propagating negative stratospheric O3 anomalies during Antarctic polar winter. The O3 anomalies are caused by geomagnetic activity and show strong hints of the EPP indirect effect.
Emma C. Leedham Elvidge, D. E. Oram, J. C. Laube, A. K. Baker, S. A. Montzka, S. Humphrey, D. A. O'Sullivan, and C. A. M. Brenninkmeijer
Atmos. Chem. Phys., 15, 1939–1958, https://doi.org/10.5194/acp-15-1939-2015, https://doi.org/10.5194/acp-15-1939-2015, 2015
N. Glatthor, M. Höpfner, G. P. Stiller, T. von Clarmann, B. Funke, S. Lossow, E. Eckert, U. Grabowski, S. Kellmann, A. Linden, K. A. Walker, and A. Wiegele
Atmos. Chem. Phys., 15, 563–582, https://doi.org/10.5194/acp-15-563-2015, https://doi.org/10.5194/acp-15-563-2015, 2015
A. Laeng, U. Grabowski, T. von Clarmann, G. Stiller, N. Glatthor, M. Höpfner, S. Kellmann, M. Kiefer, A. Linden, S. Lossow, V. Sofieva, I. Petropavlovskikh, D. Hubert, T. Bathgate, P. Bernath, C. D. Boone, C. Clerbaux, P. Coheur, R. Damadeo, D. Degenstein, S. Frith, L. Froidevaux, J. Gille, K. Hoppel, M. McHugh, Y. Kasai, J. Lumpe, N. Rahpoe, G. Toon, T. Sano, M. Suzuki, J. Tamminen, J. Urban, K. Walker, M. Weber, and J. Zawodny
Atmos. Meas. Tech., 7, 3971–3987, https://doi.org/10.5194/amt-7-3971-2014, https://doi.org/10.5194/amt-7-3971-2014, 2014
M. García-Comas, B. Funke, A. Gardini, M. López-Puertas, A. Jurado-Navarro, T. von Clarmann, G. Stiller, M. Kiefer, C. D. Boone, T. Leblanc, B. T. Marshall, M. J. Schwartz, and P. E. Sheese
Atmos. Meas. Tech., 7, 3633–3651, https://doi.org/10.5194/amt-7-3633-2014, https://doi.org/10.5194/amt-7-3633-2014, 2014
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We present the new vM21 MIPAS temperatures from 20 to 102km for all of its 2005-2012 MA, UA and NLC measurements. The main upgrades are the update of ESA L1b spectra, spectroscopic database and O and CO2 climatologies, and improvement in Tk-gradient and offset regularizations and apodization accuracy. The vM21 Tk's correct the main systematic errors of previous versions and lead to remarkable improvement in their comparisons with ACE-FTS, MLS, OSIRIS, SABER and SOFIE and the MLO and TMF lidars.
M. Sinnhuber, B. Funke, T. von Clarmann, M. Lopez-Puertas, G. P. Stiller, and A. Seppälä
Atmos. Chem. Phys., 14, 7681–7692, https://doi.org/10.5194/acp-14-7681-2014, https://doi.org/10.5194/acp-14-7681-2014, 2014
R. Eichinger and P. Jöckel
Geosci. Model Dev., 7, 1573–1582, https://doi.org/10.5194/gmd-7-1573-2014, https://doi.org/10.5194/gmd-7-1573-2014, 2014
S. Sala, H. Bönisch, T. Keber, D. E. Oram, G. Mills, and A. Engel
Atmos. Chem. Phys., 14, 6903–6923, https://doi.org/10.5194/acp-14-6903-2014, https://doi.org/10.5194/acp-14-6903-2014, 2014
B. Hassler, I. Petropavlovskikh, J. Staehelin, T. August, P. K. Bhartia, C. Clerbaux, D. Degenstein, M. De Mazière, B. M. Dinelli, A. Dudhia, G. Dufour, S. M. Frith, L. Froidevaux, S. Godin-Beekmann, J. Granville, N. R. P. Harris, K. Hoppel, D. Hubert, Y. Kasai, M. J. Kurylo, E. Kyrölä, J.-C. Lambert, P. F. Levelt, C. T. McElroy, R. D. McPeters, R. Munro, H. Nakajima, A. Parrish, P. Raspollini, E. E. Remsberg, K. H. Rosenlof, A. Rozanov, T. Sano, Y. Sasano, M. Shiotani, H. G. J. Smit, G. Stiller, J. Tamminen, D. W. Tarasick, J. Urban, R. J. van der A, J. P. Veefkind, C. Vigouroux, T. von Clarmann, C. von Savigny, K. A. Walker, M. Weber, J. Wild, and J. M. Zawodny
Atmos. Meas. Tech., 7, 1395–1427, https://doi.org/10.5194/amt-7-1395-2014, https://doi.org/10.5194/amt-7-1395-2014, 2014
A. Wisher, D. E. Oram, J. C. Laube, G. P. Mills, P. van Velthoven, A. Zahn, and C. A. M. Brenninkmeijer
Atmos. Chem. Phys., 14, 3557–3570, https://doi.org/10.5194/acp-14-3557-2014, https://doi.org/10.5194/acp-14-3557-2014, 2014
S. Meul, U. Langematz, S. Oberländer, H. Garny, and P. Jöckel
Atmos. Chem. Phys., 14, 2959–2971, https://doi.org/10.5194/acp-14-2959-2014, https://doi.org/10.5194/acp-14-2959-2014, 2014
E. Eckert, T. von Clarmann, M. Kiefer, G. P. Stiller, S. Lossow, N. Glatthor, D. A. Degenstein, L. Froidevaux, S. Godin-Beekmann, T. Leblanc, S. McDermid, M. Pastel, W. Steinbrecht, D. P. J. Swart, K. A. Walker, and P. F. Bernath
Atmos. Chem. Phys., 14, 2571–2589, https://doi.org/10.5194/acp-14-2571-2014, https://doi.org/10.5194/acp-14-2571-2014, 2014
J.-U. Grooß, I. Engel, S. Borrmann, W. Frey, G. Günther, C. R. Hoyle, R. Kivi, B. P. Luo, S. Molleker, T. Peter, M. C. Pitts, H. Schlager, G. Stiller, H. Vömel, K. A. Walker, and R. Müller
Atmos. Chem. Phys., 14, 1055–1073, https://doi.org/10.5194/acp-14-1055-2014, https://doi.org/10.5194/acp-14-1055-2014, 2014
V. Grewe, C. Frömming, S. Matthes, S. Brinkop, M. Ponater, S. Dietmüller, P. Jöckel, H. Garny, E. Tsati, K. Dahlmann, O. A. Søvde, J. Fuglestvedt, T. K. Berntsen, K. P. Shine, E. A. Irvine, T. Champougny, and P. Hullah
Geosci. Model Dev., 7, 175–201, https://doi.org/10.5194/gmd-7-175-2014, https://doi.org/10.5194/gmd-7-175-2014, 2014
S. Tegtmeier, K. Krüger, B. Quack, E. Atlas, D. R. Blake, H. Boenisch, A. Engel, H. Hepach, R. Hossaini, M. A. Navarro, S. Raimund, S. Sala, Q. Shi, and F. Ziska
Atmos. Chem. Phys., 13, 11869–11886, https://doi.org/10.5194/acp-13-11869-2013, https://doi.org/10.5194/acp-13-11869-2013, 2013
R. Hossaini, H. Mantle, M. P. Chipperfield, S. A. Montzka, P. Hamer, F. Ziska, B. Quack, K. Krüger, S. Tegtmeier, E. Atlas, S. Sala, A. Engel, H. Bönisch, T. Keber, D. Oram, G. Mills, C. Ordóñez, A. Saiz-Lopez, N. Warwick, Q. Liang, W. Feng, F. Moore, B. R. Miller, V. Marécal, N. A. D. Richards, M. Dorf, and K. Pfeilsticker
Atmos. Chem. Phys., 13, 11819–11838, https://doi.org/10.5194/acp-13-11819-2013, https://doi.org/10.5194/acp-13-11819-2013, 2013
V. F. Sofieva, N. Rahpoe, J. Tamminen, E. Kyrölä, N. Kalakoski, M. Weber, A. Rozanov, C. von Savigny, A. Laeng, T. von Clarmann, G. Stiller, S. Lossow, D. Degenstein, A. Bourassa, C. Adams, C. Roth, N. Lloyd, P. Bernath, R. J. Hargreaves, J. Urban, D. Murtagh, A. Hauchecorne, F. Dalaudier, M. van Roozendael, N. Kalb, and C. Zehner
Earth Syst. Sci. Data, 5, 349–363, https://doi.org/10.5194/essd-5-349-2013, https://doi.org/10.5194/essd-5-349-2013, 2013
P. Braesicke, J. Keeble, X. Yang, G. Stiller, S. Kellmann, N. L. Abraham, A. Archibald, P. Telford, and J. A. Pyle
Atmos. Chem. Phys., 13, 10677–10688, https://doi.org/10.5194/acp-13-10677-2013, https://doi.org/10.5194/acp-13-10677-2013, 2013
M. Höpfner, N. Glatthor, U. Grabowski, S. Kellmann, M. Kiefer, A. Linden, J. Orphal, G. Stiller, T. von Clarmann, B. Funke, and C. D. Boone
Atmos. Chem. Phys., 13, 10405–10423, https://doi.org/10.5194/acp-13-10405-2013, https://doi.org/10.5194/acp-13-10405-2013, 2013
M. von Hobe, S. Bekki, S. Borrmann, F. Cairo, F. D'Amato, G. Di Donfrancesco, A. Dörnbrack, A. Ebersoldt, M. Ebert, C. Emde, I. Engel, M. Ern, W. Frey, S. Genco, S. Griessbach, J.-U. Grooß, T. Gulde, G. Günther, E. Hösen, L. Hoffmann, V. Homonnai, C. R. Hoyle, I. S. A. Isaksen, D. R. Jackson, I. M. Jánosi, R. L. Jones, K. Kandler, C. Kalicinsky, A. Keil, S. M. Khaykin, F. Khosrawi, R. Kivi, J. Kuttippurath, J. C. Laube, F. Lefèvre, R. Lehmann, S. Ludmann, B. P. Luo, M. Marchand, J. Meyer, V. Mitev, S. Molleker, R. Müller, H. Oelhaf, F. Olschewski, Y. Orsolini, T. Peter, K. Pfeilsticker, C. Piesch, M. C. Pitts, L. R. Poole, F. D. Pope, F. Ravegnani, M. Rex, M. Riese, T. Röckmann, B. Rognerud, A. Roiger, C. Rolf, M. L. Santee, M. Scheibe, C. Schiller, H. Schlager, M. Siciliani de Cumis, N. Sitnikov, O. A. Søvde, R. Spang, N. Spelten, F. Stordal, O. Sumińska-Ebersoldt, A. Ulanovski, J. Ungermann, S. Viciani, C. M. Volk, M. vom Scheidt, P. von der Gathen, K. Walker, T. Wegner, R. Weigel, S. Weinbruch, G. Wetzel, F. G. Wienhold, I. Wohltmann, W. Woiwode, I. A. K. Young, V. Yushkov, B. Zobrist, and F. Stroh
Atmos. Chem. Phys., 13, 9233–9268, https://doi.org/10.5194/acp-13-9233-2013, https://doi.org/10.5194/acp-13-9233-2013, 2013
Y. Kasai, H. Sagawa, D. Kreyling, E. Dupuy, P. Baron, J. Mendrok, K. Suzuki, T. O. Sato, T. Nishibori, S. Mizobuchi, K. Kikuchi, T. Manabe, H. Ozeki, T. Sugita, M. Fujiwara, Y. Irimajiri, K. A. Walker, P. F. Bernath, C. Boone, G. Stiller, T. von Clarmann, J. Orphal, J. Urban, D. Murtagh, E. J. Llewellyn, D. Degenstein, A. E. Bourassa, N. D. Lloyd, L. Froidevaux, M. Birk, G. Wagner, F. Schreier, J. Xu, P. Vogt, T. Trautmann, and M. Yasui
Atmos. Meas. Tech., 6, 2311–2338, https://doi.org/10.5194/amt-6-2311-2013, https://doi.org/10.5194/amt-6-2311-2013, 2013
P. D. Hamer, V. Marécal, R. Hossaini, M. Pirre, N. Warwick, M. Chipperfield, A. A. Samah, N. Harris, A. Robinson, B. Quack, A. Engel, K. Krüger, E. Atlas, K. Subramaniam, D. Oram, Emma C. Leedham Elvidge, G. Mills, K. Pfeilsticker, S. Sala, T. Keber, H. Bönisch, L. K. Peng, M. S. M. Nadzir, P. T. Lim, A. Mujahid, A. Anton, H. Schlager, V. Catoire, G. Krysztofiak, S. Fühlbrügge, M. Dorf, and W. T. Sturges
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-13-20611-2013, https://doi.org/10.5194/acpd-13-20611-2013, 2013
Revised manuscript not accepted
H. Garny, G. E. Bodeker, D. Smale, M. Dameris, and V. Grewe
Atmos. Chem. Phys., 13, 7279–7300, https://doi.org/10.5194/acp-13-7279-2013, https://doi.org/10.5194/acp-13-7279-2013, 2013
B. Tschanz, C. Straub, D. Scheiben, K. A. Walker, G. P. Stiller, and N. Kämpfer
Atmos. Meas. Tech., 6, 1725–1745, https://doi.org/10.5194/amt-6-1725-2013, https://doi.org/10.5194/amt-6-1725-2013, 2013
G. Wetzel, H. Oelhaf, G. Berthet, A. Bracher, C. Cornacchia, D. G. Feist, H. Fischer, A. Fix, M. Iarlori, A. Kleinert, A. Lengel, M. Milz, L. Mona, S. C. Müller, J. Ovarlez, G. Pappalardo, C. Piccolo, P. Raspollini, J.-B. Renard, V. Rizi, S. Rohs, C. Schiller, G. Stiller, M. Weber, and G. Zhang
Atmos. Chem. Phys., 13, 5791–5811, https://doi.org/10.5194/acp-13-5791-2013, https://doi.org/10.5194/acp-13-5791-2013, 2013
F. Khosrawi, R. Müller, J. Urban, M. H. Proffitt, G. Stiller, M. Kiefer, S. Lossow, D. Kinnison, F. Olschewski, M. Riese, and D. Murtagh
Atmos. Chem. Phys., 13, 3619–3641, https://doi.org/10.5194/acp-13-3619-2013, https://doi.org/10.5194/acp-13-3619-2013, 2013
J. C. Laube, A. Keil, H. Bönisch, A. Engel, T. Röckmann, C. M. Volk, and W. T. Sturges
Atmos. Chem. Phys., 13, 2779–2791, https://doi.org/10.5194/acp-13-2779-2013, https://doi.org/10.5194/acp-13-2779-2013, 2013
F. Friederich, T. von Clarmann, B. Funke, H. Nieder, J. Orphal, M. Sinnhuber, G. P. Stiller, and J. M. Wissing
Atmos. Chem. Phys., 13, 2531–2539, https://doi.org/10.5194/acp-13-2531-2013, https://doi.org/10.5194/acp-13-2531-2013, 2013
S. Takele Kenea, G. Mengistu Tsidu, T. Blumenstock, F. Hase, T. von Clarmann, and G. P. Stiller
Atmos. Meas. Tech., 6, 495–509, https://doi.org/10.5194/amt-6-495-2013, https://doi.org/10.5194/amt-6-495-2013, 2013
S. Kellmann, T. von Clarmann, G. P. Stiller, E. Eckert, N. Glatthor, M. Höpfner, M. Kiefer, J. Orphal, B. Funke, U. Grabowski, A. Linden, G. S. Dutton, and J. W. Elkins
Atmos. Chem. Phys., 12, 11857–11875, https://doi.org/10.5194/acp-12-11857-2012, https://doi.org/10.5194/acp-12-11857-2012, 2012
Related subject area
Subject: Gases | Research Activity: Atmospheric Modelling and Data Analysis | Altitude Range: Stratosphere | Science Focus: Chemistry (chemical composition and reactions)
On the atmospheric budget of 1,2-dichloroethane and its impact on stratospheric chlorine and ozone (2002–2020)
The return to 1980 stratospheric halogen levels: a moving target in ozone assessments from 2006 to 2022
The impact of dehydration and extremely low HCl values in the Antarctic stratospheric vortex in mid-winter on ozone loss in spring
Beyond self-healing: stabilizing and destabilizing photochemical adjustment of the ozone layer
Solar FTIR measurements of NOx vertical distributions – Part 2: Experiment-based scaling factors describing the daytime variation in stratospheric NOx
Technical note: Evaluation of the Copernicus Atmosphere Monitoring Service Cy48R1 upgrade of June 2023
Ozone trends in homogenized Umkehr, Ozonesonde, and COH overpass records
Protection without poison: Why tropical ozone maximizes in the interior of the atmosphere
Analysis of a newly homogenised ozonesonde dataset from Lauder, New Zealand
Opinion: Stratospheric ozone – depletion, recovery and new challenges
Quantum yields of CHDO above 300 nm
Sensitivities of atmospheric composition and climate to altitude and latitude of hypersonic aircraft emissions
Atmospheric impacts of chlorinated very short-lived substances over the recent past – Part 2: Impacts on ozone
N2O as a regression proxy for dynamical variability in stratospheric trace gas trends
The influence of future changes in springtime Arctic ozone on stratospheric and surface climate
Weakening of springtime Arctic ozone depletion with climate change
The impact of an extreme solar event on the middle atmosphere: a case study
The future ozone trends in changing climate simulated with SOCOLv4
Atmospheric distribution of HCN from satellite observations and 3-D model simulations
Indicators of the ozone recovery for selected sites in the Northern Hemisphere mid-latitudes derived from various total column ozone datasets (1980–2020)
The historical ozone trends simulated with the SOCOLv4 and their comparison with observations and reanalyses
Atmospheric impacts of chlorinated very short-lived substances over the recent past – Part 1: Stratospheric chlorine budget and the role of transport
Effects of reanalysis forcing fields on ozone trends and age of air from a chemical transport model
The influence of energetic particle precipitation on Antarctic stratospheric chlorine and ozone over the 20th century
From the middle stratosphere to the surface, using nitrous oxide to constrain the stratosphere–troposphere exchange of ozone
An Arctic ozone hole in 2020 if not for the Montreal Protocol
Effects of enhanced downwelling of NOx on Antarctic upper-stratospheric ozone in the 21st century
Processes influencing lower stratospheric water vapour in monsoon anticyclones: insights from Lagrangian modelling
Evaluating stratospheric ozone and water vapour changes in CMIP6 models from 1850 to 2100
Slow feedbacks resulting from strongly enhanced atmospheric methane mixing ratios in a chemistry–climate model with mixed-layer ocean
Impact of the eruption of Mt Pinatubo on the chemical composition of the stratosphere
Projecting ozone hole recovery using an ensemble of chemistry–climate models weighted by model performance and independence
Inconsistencies between chemistry–climate models and observed lower stratospheric ozone trends since 1998
Reformulating the bromine alpha factor and equivalent effective stratospheric chlorine (EESC): evolution of ozone destruction rates of bromine and chlorine in future climate scenarios
Analysis and attribution of total column ozone changes over the Tibetan Plateau during 1979–2017
Seasonal impact of biogenic very short-lived bromocarbons on lowermost stratospheric ozone between 60° N and 60° S during the 21st century
Modelling the potential impacts of the recent, unexpected increase in CFC-11 emissions on total column ozone recovery
The potential impacts of a sulfur- and halogen-rich supereruption such as Los Chocoyos on the atmosphere and climate
Technical note: Intermittent reduction of the stratospheric ozone over northern Europe caused by a storm in the Atlantic Ocean
Possible implications of enhanced chlorofluorocarbon-11 concentrations on ozone
Technical note: Reanalysis of Aura MLS chemical observations
Separating the role of direct radiative heating and photolysis in modulating the atmospheric response to the amplitude of the 11-year solar cycle forcing
Reactive nitrogen (NOy) and ozone responses to energetic electron precipitation during Southern Hemisphere winter
Implication of strongly increased atmospheric methane concentrations for chemistry–climate connections
Multitimescale variations in modeled stratospheric water vapor derived from three modern reanalysis products
How robust are stratospheric age of air trends from different reanalyses?
Evaluation of CESM1 (WACCM) free-running and specified dynamics atmospheric composition simulations using global multispecies satellite data records
Chlorine nitrate in the atmosphere
Linking uncertainty in simulated Arctic ozone loss to uncertainties in modelled tropical stratospheric water vapour
Importance of seasonally resolved oceanic emissions for bromoform delivery from the tropical Indian Ocean and west Pacific to the stratosphere
Ryan Hossaini, David Sherry, Zihao Wang, Martyn P. Chipperfield, Wuhu Feng, David E. Oram, Karina E. Adcock, Stephen A. Montzka, Isobel J. Simpson, Andrea Mazzeo, Amber A. Leeson, Elliot Atlas, and Charles C.-K. Chou
Atmos. Chem. Phys., 24, 13457–13475, https://doi.org/10.5194/acp-24-13457-2024, https://doi.org/10.5194/acp-24-13457-2024, 2024
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DCE (1,2-dichloroethane) is an industrial chemical used to produce PVC (polyvinyl chloride). We analysed DCE production data to estimate global DCE emissions (2002–2020). The emissions were included in an atmospheric model and evaluated by comparing simulated DCE to DCE measurements in the troposphere. We show that DCE contributes ozone-depleting Cl to the stratosphere and that this has increased with increasing DCE emissions. DCE’s impact on stratospheric O3 is currently small but non-zero.
Megan J. Lickley, John S. Daniel, Laura A. McBride, Ross J. Salawitch, and Guus J. M. Velders
Atmos. Chem. Phys., 24, 13081–13099, https://doi.org/10.5194/acp-24-13081-2024, https://doi.org/10.5194/acp-24-13081-2024, 2024
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The expected ozone recovery date was delayed by 17 years between the 2006 and 2022 international scientific assessments of ozone depletion. We quantify the primary drivers of this delay. Changes in the metric used to estimate ozone recovery explain ca. 5 years of this delay. Of the remaining 12 years, changes in estimated banks, atmospheric lifetimes, and emission projections explain 4, 3.5, and 3 years of this delay, respectively.
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.
Aaron Match, Edwin P. Gerber, and Stephan Fueglistaler
Atmos. Chem. Phys., 24, 10305–10322, https://doi.org/10.5194/acp-24-10305-2024, https://doi.org/10.5194/acp-24-10305-2024, 2024
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Earth's ozone layer absorbs incoming UV light, protecting life. Removing ozone aloft allows UV light to penetrate deeper, where it is known to produce new ozone, leading to "self-healing" that partially stabilizes total ozone. However, a photochemistry model shows that, above 40 km in the tropics, deeper-penetrating UV destroys ozone, destabilizing the total ozone. Photochemical theory reveals that this destabilizing regime occurs where overhead ozone is below a key threshold.
Pinchas Nürnberg, Sarah A. Strode, and Ralf Sussmann
Atmos. Chem. Phys., 24, 10001–10012, https://doi.org/10.5194/acp-24-10001-2024, https://doi.org/10.5194/acp-24-10001-2024, 2024
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We created a set of scaling factors describing the diurnal increase in stratospheric nitrogen oxides above Zugspitze, Germany. We used these factors to validate recently published model simulation data. On the one hand, this validation enables the use of the validated data to better understand the stratospheric photochemistry. On the other hand, it can improve satellite validation, which has implications for the understanding of urban smog events and other pollution events in the troposphere.
Henk Eskes, Athanasios Tsikerdekis, Melanie Ades, Mihai Alexe, Anna Carlin Benedictow, Yasmine Bennouna, Lewis Blake, Idir Bouarar, Simon Chabrillat, Richard Engelen, Quentin Errera, Johannes Flemming, Sebastien Garrigues, Jan Griesfeller, Vincent Huijnen, Luka Ilić, Antje Inness, John Kapsomenakis, Zak Kipling, Bavo Langerock, Augustin Mortier, Mark Parrington, Isabelle Pison, Mikko Pitkänen, Samuel Remy, Andreas Richter, Anja Schoenhardt, Michael Schulz, Valerie Thouret, Thorsten Warneke, Christos Zerefos, and Vincent-Henri Peuch
Atmos. Chem. Phys., 24, 9475–9514, https://doi.org/10.5194/acp-24-9475-2024, https://doi.org/10.5194/acp-24-9475-2024, 2024
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The Copernicus Atmosphere Monitoring Service (CAMS) provides global analyses and forecasts of aerosols and trace gases in the atmosphere. On 27 June 2023 a major upgrade, Cy48R1, became operational. Comparisons with in situ, surface remote sensing, aircraft, and balloon and satellite observations show that the new CAMS system is a significant improvement. The results quantify the skill of CAMS to forecast impactful events, such as wildfires, dust storms and air pollution peaks.
Irina Petropavlovskikh, Jeannette D. Wild, Kari Abromitis, Peter Effertz, Koji Miyagawa, Lawrence E. Flynn, Eliane Maillard-Barra, Robert Damadeo, Glen McConville, Bryan Johnson, Patrick Cullis, Sophie Godin-Beekmann, Gerald Ancellet, Richard Querel, Roeland Van Malderen, and Daniel Zawada
EGUsphere, https://doi.org/10.5194/egusphere-2024-1821, https://doi.org/10.5194/egusphere-2024-1821, 2024
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Observational records show that stratospheric ozone is recovering in accordance with the implementation of the Montreal protocol and its amendments. The natural ozone variability complicates detection of small trends. This study optimizes statistical model fit in the observational records by adding parameters that interpret seasonal and long-term changes in atmospheric circulation and airmass mixing which reduces uncertainties in detection of the stratospheric ozone recovery.
Aaron Match, Edwin P. Gerber, and Stephan Fueglistaler
EGUsphere, https://doi.org/10.5194/egusphere-2024-1552, https://doi.org/10.5194/egusphere-2024-1552, 2024
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Explanations for the tropical ozone maximum at 26 km have fragmented into two paradigms, shown to represent limiting regimes of ozone photochemistry with production by UV and generalized destruction by catalytic cycles and transport. Paradoxically, neither paradigm explains the observed ozone peak, motivating a new theory: peak ozone occurs precisely at the transition between these regimes. An idealized analytical ozone profile is derived, helping to interpret sensitivities to UV perturbations.
Guang Zeng, Richard Querel, Hisako Shiona, Deniz Poyraz, Roeland Van Malderen, Alex Geddes, Penny Smale, Dan Smale, John Robinson, and Olaf Morgenstern
Atmos. Chem. Phys., 24, 6413–6432, https://doi.org/10.5194/acp-24-6413-2024, https://doi.org/10.5194/acp-24-6413-2024, 2024
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We present a homogenised ozonesonde record (1987–2020) for Lauder, a Southern Hemisphere mid-latitude site; identify factors driving ozone trends; and attribute them to anthropogenic forcings using statistical analysis and model simulations. We find that significant negative lower-stratospheric ozone trends identified at Lauder are associated with an increase in tropopause height and that CO2-driven dynamical changes have played an increasingly important role in driving ozone trends.
Martyn P. Chipperfield and Slimane Bekki
Atmos. Chem. Phys., 24, 2783–2802, https://doi.org/10.5194/acp-24-2783-2024, https://doi.org/10.5194/acp-24-2783-2024, 2024
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We give a personal perspective on recent issues related to the depletion of stratospheric ozone and some newly emerging challenges. We first provide a brief review of historic work on understanding the ozone layer and review ozone recovery from the effects of halogenated source gases and the Montreal Protocol. We then discuss the recent observations of ozone depletion from Australian fires in early 2020 and the Hunga Tonga–Hunga Ha'apai volcano in January 2022.
Ernst-Peter Röth and Luc Vereecken
Atmos. Chem. Phys., 24, 2625–2638, https://doi.org/10.5194/acp-24-2625-2024, https://doi.org/10.5194/acp-24-2625-2024, 2024
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The paper presents the radical and molecular product quantum yields in the photolysis reaction of CHDO at wavelengths above 300 nm. Two different approaches based on literature data are used, with results falling within both approaches' uncertainty ranges. Simple functional forms are presented for use in photochemical models of the atmosphere.
Johannes Pletzer and Volker Grewe
Atmos. Chem. Phys., 24, 1743–1775, https://doi.org/10.5194/acp-24-1743-2024, https://doi.org/10.5194/acp-24-1743-2024, 2024
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Very fast aircraft can travel at 30–40 km altitude and are designed to use liquid hydrogen as fuel instead of kerosene. Depending on their flight altitude, the impact of these aircraft on the atmosphere and climate can change very much. Our results show that a variation inflight latitude can have a considerably higher change in impact compared to a variation in flight altitude. Atmospheric air transport and polar stratospheric clouds play an important role in hypersonic aircraft emissions.
Ewa M. Bednarz, Ryan Hossaini, and Martyn P. Chipperfield
Atmos. Chem. Phys., 23, 13701–13711, https://doi.org/10.5194/acp-23-13701-2023, https://doi.org/10.5194/acp-23-13701-2023, 2023
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We quantify, for the first time, the time-varying impact of uncontrolled emissions of chlorinated very short-lived substances (Cl-VSLSs) on stratospheric ozone using a state-of-the-art chemistry-climate model. We demonstrate that Cl-VSLSs already have a non-negligible impact on stratospheric ozone, including a local reduction of up to ~7 DU in Arctic ozone in the cold winter of 2019/20, and any so future growth in emissions will continue to offset some of the benefits of the Montreal Protocol.
Kimberlee Dubé, Susann Tegtmeier, Adam Bourassa, Daniel Zawada, Douglas Degenstein, Patrick E. Sheese, Kaley A. Walker, and William Randel
Atmos. Chem. Phys., 23, 13283–13300, https://doi.org/10.5194/acp-23-13283-2023, https://doi.org/10.5194/acp-23-13283-2023, 2023
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This paper presents a technique for understanding the causes of long-term changes in stratospheric composition. By using N2O as a proxy for stratospheric circulation in the model used to calculated trends, it is possible to separate the effects of dynamics and chemistry on observed trace gas trends. We find that observed HCl increases are due to changes in the stratospheric circulation, as are O3 decreases above 30 hPa in the Northern Hemisphere.
Gabriel Chiodo, Marina Friedel, Svenja Seeber, Daniela Domeisen, Andrea Stenke, Timofei Sukhodolov, and Franziska Zilker
Atmos. Chem. Phys., 23, 10451–10472, https://doi.org/10.5194/acp-23-10451-2023, https://doi.org/10.5194/acp-23-10451-2023, 2023
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Stratospheric ozone protects the biosphere from harmful UV radiation. Anthropogenic activity has led to a reduction in the ozone layer in the recent past, but thanks to the implementation of the Montreal Protocol, the ozone layer is projected to recover. In this study, we show that projected future changes in Arctic ozone abundances during springtime will influence stratospheric climate and thereby actively modulate large-scale circulation changes in the Northern Hemisphere.
Marina Friedel, Gabriel Chiodo, Timofei Sukhodolov, James Keeble, Thomas Peter, Svenja Seeber, Andrea Stenke, Hideharu Akiyoshi, Eugene Rozanov, David Plummer, Patrick Jöckel, Guang Zeng, Olaf Morgenstern, and Béatrice Josse
Atmos. Chem. Phys., 23, 10235–10254, https://doi.org/10.5194/acp-23-10235-2023, https://doi.org/10.5194/acp-23-10235-2023, 2023
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Previously, it has been suggested that springtime Arctic ozone depletion might worsen in the coming decades due to climate change, which might counteract the effect of reduced ozone-depleting substances. Here, we show with different chemistry–climate models that springtime Arctic ozone depletion will likely decrease in the future. Further, we explain why models show a large spread in the projected development of Arctic ozone depletion and use the model spread to constrain future projections.
Thomas Reddmann, Miriam Sinnhuber, Jan Maik Wissing, Olesya Yakovchuk, and Ilya Usoskin
Atmos. Chem. Phys., 23, 6989–7000, https://doi.org/10.5194/acp-23-6989-2023, https://doi.org/10.5194/acp-23-6989-2023, 2023
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Recent analyses of isotopic records of ice cores and sediments have shown that very strong explosions may occur on the Sun, perhaps about one such explosion every 1000 years. Such explosions pose a real threat to humankind. It is therefore of great interest to study the impact of such explosions on Earth. We analyzed how the explosions would affect the chemistry of the middle atmosphere and show that the related ozone loss is not dramatic and that the atmosphere will recover within 1 year.
Arseniy Karagodin-Doyennel, Eugene Rozanov, Timofei Sukhodolov, Tatiana Egorova, Jan Sedlacek, and Thomas Peter
Atmos. Chem. Phys., 23, 4801–4817, https://doi.org/10.5194/acp-23-4801-2023, https://doi.org/10.5194/acp-23-4801-2023, 2023
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The future ozone evolution in SOCOLv4 simulations under SSP2-4.5 and SSP5-8.5 scenarios has been assessed for the period 2015–2099 and subperiods using the DLM approach. The SOCOLv4 projects a decline in tropospheric ozone in the 2030s in SSP2-4.5 and in the 2060s in SSP5-8.5. The stratospheric ozone increase is ~3 times higher in SSP5-8.5, confirming the important role of GHGs in ozone evolution. We also showed that tropospheric ozone strongly impacts the total column in the tropics.
Antonio G. Bruno, Jeremy J. Harrison, Martyn P. Chipperfield, David P. Moore, Richard J. Pope, Christopher Wilson, Emmanuel Mahieu, and Justus Notholt
Atmos. Chem. Phys., 23, 4849–4861, https://doi.org/10.5194/acp-23-4849-2023, https://doi.org/10.5194/acp-23-4849-2023, 2023
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A 3-D chemical transport model, TOMCAT; satellite data; and ground-based observations have been used to investigate hydrogen cyanide (HCN) variability. We found that the oxidation by O(1D) drives the HCN loss in the middle stratosphere and the currently JPL-recommended OH reaction rate overestimates HCN atmospheric loss. We also evaluated two different ocean uptake schemes. We found them to be unrealistic, and we need to scale these schemes to obtain good agreement with HCN observations.
Janusz Krzyścin
Atmos. Chem. Phys., 23, 3119–3132, https://doi.org/10.5194/acp-23-3119-2023, https://doi.org/10.5194/acp-23-3119-2023, 2023
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We propose indices to obtain the current stage of total column ozone (TCO3) recovery attributed to ozone-depleting substance (ODS) changes in the stratosphere. The indices are calculated using TCO3 values in key years of the ODS changes. The ozone recovery stage is derived for 16 sites in the NH mid-latitudes using results from ground and satellite measurements and reanalysis data. In Europe, there is a slow TCO3 recovery. A continuous TCO3 decline has been occurring in some sites since 1980.
Arseniy Karagodin-Doyennel, Eugene Rozanov, Timofei Sukhodolov, Tatiana Egorova, Jan Sedlacek, William Ball, and Thomas Peter
Atmos. Chem. Phys., 22, 15333–15350, https://doi.org/10.5194/acp-22-15333-2022, https://doi.org/10.5194/acp-22-15333-2022, 2022
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Applying the dynamic linear model, we confirm near-global ozone recovery (55°N–55°S) in the mesosphere, upper and middle stratosphere, and a steady increase in the troposphere. We also show that modern chemistry–climate models (CCMs) like SOCOLv4 may reproduce the observed trend distribution of lower stratospheric ozone, despite exhibiting a lower magnitude and statistical significance. The obtained ozone trend pattern in SOCOLv4 is generally consistent with observations and reanalysis datasets.
Ewa M. Bednarz, Ryan Hossaini, Martyn P. Chipperfield, N. Luke Abraham, and Peter Braesicke
Atmos. Chem. Phys., 22, 10657–10676, https://doi.org/10.5194/acp-22-10657-2022, https://doi.org/10.5194/acp-22-10657-2022, 2022
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Atmospheric impacts of chlorinated very short-lived substances (Cl-VSLS) over the first two decades of the 21st century are assessed using the UM-UKCA chemistry–climate model. Stratospheric input of Cl from Cl-VSLS is estimated at ~130 ppt in 2019. The use of model set-up with constrained meteorology significantly increases the abundance of Cl-VSLS in the lower stratosphere relative to the free-running set-up. The growth in Cl-VSLS emissions significantly impacted recent HCl and COCl2 trends.
Yajuan Li, Sandip S. Dhomse, Martyn P. Chipperfield, Wuhu Feng, Andreas Chrysanthou, Yuan Xia, and Dong Guo
Atmos. Chem. Phys., 22, 10635–10656, https://doi.org/10.5194/acp-22-10635-2022, https://doi.org/10.5194/acp-22-10635-2022, 2022
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Chemical transport models forced with (re)analysis meteorological fields are ideally suited for interpreting the influence of important physical processes on the ozone variability. We use TOMCAT forced by ECMWF ERA-Interim and ERA5 reanalysis data sets to investigate the effects of reanalysis forcing fields on ozone changes. Our results show that models forced by ERA5 reanalyses may not yet be capable of reproducing observed changes in stratospheric ozone, particularly in the lower stratosphere.
Ville Maliniemi, Pavle Arsenovic, Annika Seppälä, and Hilde Nesse Tyssøy
Atmos. Chem. Phys., 22, 8137–8149, https://doi.org/10.5194/acp-22-8137-2022, https://doi.org/10.5194/acp-22-8137-2022, 2022
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We simulate the effect of energetic particle precipitation (EPP) on Antarctic stratospheric ozone chemistry over the whole 20th century. We find a significant increase of reactive nitrogen due to EP, which can deplete ozone via a catalytic reaction. Furthermore, significant modulation of active chlorine is obtained related to EPP, which impacts ozone depletion by both active chlorine and EPP. Our results show that EPP has been a significant modulator of ozone chemistry during the CFC era.
Daniel J. Ruiz and Michael J. Prather
Atmos. Chem. Phys., 22, 2079–2093, https://doi.org/10.5194/acp-22-2079-2022, https://doi.org/10.5194/acp-22-2079-2022, 2022
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The stratosphere is an important source of tropospheric ozone, which affects climate, chemistry, and air quality, but is extremely difficult to quantify given the large production and loss terms in the troposphere. Here, we use other gases that are well observed and quantified as a reference to test our simulations of ozone transport in the atmosphere. This allows us to better constrain the stratospheric source of ozone and also offers guidance to improve future simulations of ozone transport.
Catherine Wilka, Susan Solomon, Doug Kinnison, and David Tarasick
Atmos. Chem. Phys., 21, 15771–15781, https://doi.org/10.5194/acp-21-15771-2021, https://doi.org/10.5194/acp-21-15771-2021, 2021
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We use satellite and balloon measurements to evaluate modeled ozone loss seen in the unusually cold Arctic of 2020 in the real world and compare it to simulations of a world avoided. We show that extensive denitrification in 2020 provides an important test case for stratospheric model process representations. If the Montreal Protocol had not banned ozone-depleting substances, an Arctic ozone hole would have emerged for the first time in spring 2020 that is comparable to those in the Antarctic.
Ville Maliniemi, Hilde Nesse Tyssøy, Christine Smith-Johnsen, Pavle Arsenovic, and Daniel R. Marsh
Atmos. Chem. Phys., 21, 11041–11052, https://doi.org/10.5194/acp-21-11041-2021, https://doi.org/10.5194/acp-21-11041-2021, 2021
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We simulate ozone variability over the 21st century with different greenhouse gas scenarios. Our results highlight a novel mechanism of additional reactive nitrogen species descending to the Antarctic stratosphere from the thermosphere/upper mesosphere due to the accelerated residual circulation under climate change. This excess descending NOx can potentially prevent a super recovery of ozone in the Antarctic upper stratosphere.
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.
James Keeble, Birgit Hassler, Antara Banerjee, Ramiro Checa-Garcia, Gabriel Chiodo, Sean Davis, Veronika Eyring, Paul T. Griffiths, Olaf Morgenstern, Peer Nowack, Guang Zeng, Jiankai Zhang, Greg Bodeker, Susannah Burrows, Philip Cameron-Smith, David Cugnet, Christopher Danek, Makoto Deushi, Larry W. Horowitz, Anne Kubin, Lijuan Li, Gerrit Lohmann, Martine Michou, Michael J. Mills, Pierre Nabat, Dirk Olivié, Sungsu Park, Øyvind Seland, Jens Stoll, Karl-Hermann Wieners, and Tongwen Wu
Atmos. Chem. Phys., 21, 5015–5061, https://doi.org/10.5194/acp-21-5015-2021, https://doi.org/10.5194/acp-21-5015-2021, 2021
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Stratospheric ozone and water vapour are key components of the Earth system; changes to both have important impacts on global and regional climate. We evaluate changes to these species from 1850 to 2100 in the new generation of CMIP6 models. There is good agreement between the multi-model mean and observations, although there is substantial variation between the individual models. The future evolution of both ozone and water vapour is strongly dependent on the assumed future emissions scenario.
Laura Stecher, Franziska Winterstein, Martin Dameris, Patrick Jöckel, Michael Ponater, and Markus Kunze
Atmos. Chem. Phys., 21, 731–754, https://doi.org/10.5194/acp-21-731-2021, https://doi.org/10.5194/acp-21-731-2021, 2021
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This study investigates the impact of strongly increased atmospheric methane mixing ratios on the Earth's climate. An interactive model system including atmospheric dynamics, chemistry, and a mixed-layer ocean model is used to analyse the effect of doubled and quintupled methane mixing ratios. We assess feedbacks on atmospheric chemistry and changes in the stratospheric circulation, focusing on the impact of tropospheric warming, and their relevance for the model's climate sensitivity.
Markus Kilian, Sabine Brinkop, and Patrick Jöckel
Atmos. Chem. Phys., 20, 11697–11715, https://doi.org/10.5194/acp-20-11697-2020, https://doi.org/10.5194/acp-20-11697-2020, 2020
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After the volcanic eruption of Mt Pinatubo in 1991, ozone decreased in the tropics and increased in the midlatitudes and polar regions for 1 year. The change in the ozone column is solely a result of the volcanic heating, followed by an ozone decrease in the higher latitudes. This is caused by the volcanic aerosol, which changes the heterogeneous chemistry and thus the catalytic ozone loss cycles. Vertical transport of water vapour is enhanced by volcanic heating and increases methane.
Matt Amos, Paul J. Young, J. Scott Hosking, Jean-François Lamarque, N. Luke Abraham, Hideharu Akiyoshi, Alexander T. Archibald, Slimane Bekki, Makoto Deushi, Patrick Jöckel, Douglas Kinnison, Ole Kirner, Markus Kunze, Marion Marchand, David A. Plummer, David Saint-Martin, Kengo Sudo, Simone Tilmes, and Yousuke Yamashita
Atmos. Chem. Phys., 20, 9961–9977, https://doi.org/10.5194/acp-20-9961-2020, https://doi.org/10.5194/acp-20-9961-2020, 2020
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We present an updated projection of Antarctic ozone hole recovery using an ensemble of chemistry–climate models. To do so, we employ a method, more advanced and skilful than the current multi-model mean standard, which is applicable to other ensemble analyses. It calculates the performance and similarity of the models, which we then use to weight the model. Calculating model similarity allows us to account for models which are constructed from similar components.
William T. Ball, Gabriel Chiodo, Marta Abalos, Justin Alsing, and Andrea Stenke
Atmos. Chem. Phys., 20, 9737–9752, https://doi.org/10.5194/acp-20-9737-2020, https://doi.org/10.5194/acp-20-9737-2020, 2020
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Recent lower stratospheric ozone decreases remain unexplained. We show that chemistry–climate models are not generally able to reproduce mid-latitude ozone and water vapour changes. Our analysis of observations provides evidence that climate change may be responsible for the ozone trends. While model projections suggest that extratropical ozone should recover by 2100, our study raises questions about their efficacy in simulating lower stratospheric changes in this region.
J. Eric Klobas, Debra K. Weisenstein, Ross J. Salawitch, and David M. Wilmouth
Atmos. Chem. Phys., 20, 9459–9471, https://doi.org/10.5194/acp-20-9459-2020, https://doi.org/10.5194/acp-20-9459-2020, 2020
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The rates of important ozone-destroying chemical reactions in the stratosphere are likely to change in the future. We employ a computer model to evaluate how the rates of ozone destruction by chlorine and bromine may evolve in four climate change scenarios with the introduction of the eta factor. We then show how these changing rates will impact the ozone-depleting power of the stratosphere with a new metric known as Equivalent Effective Stratospheric Benchmark-normalized Chlorine (EESBnC).
Yajuan Li, Martyn P. Chipperfield, Wuhu Feng, Sandip S. Dhomse, Richard J. Pope, Faquan Li, and Dong Guo
Atmos. Chem. Phys., 20, 8627–8639, https://doi.org/10.5194/acp-20-8627-2020, https://doi.org/10.5194/acp-20-8627-2020, 2020
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The Tibetan Plateau (TP) exerts important thermal and dynamical effects on atmospheric circulation, climate change as well as the ozone distribution. In this study, we use updated observations and model simulations to investigate the ozone trends and variations over the TP. Wintertime TP ozone variations are largely controlled by tropical to high-latitude transport processes, whereas summertime concentrations are a combined effect of photochemical decay and tropical processes.
Javier Alejandro Barrera, Rafael Pedro Fernandez, Fernando Iglesias-Suarez, Carlos Alberto Cuevas, Jean-Francois Lamarque, and Alfonso Saiz-Lopez
Atmos. Chem. Phys., 20, 8083–8102, https://doi.org/10.5194/acp-20-8083-2020, https://doi.org/10.5194/acp-20-8083-2020, 2020
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The inclusion of biogenic very short-lived bromocarbons (VSLBr) in the CAM-chem model improves the model–satellite agreement of the total ozone columns at mid-latitudes and drives a persistent hemispheric asymmetry in lowermost stratospheric ozone loss. The seasonal VSLBr impact on mid-latitude lowermost stratospheric ozone is influenced by the heterogeneous reactivation processes of inorganic chlorine on ice crystals, with a clear increase in ozone destruction during spring and winter.
James Keeble, N. Luke Abraham, Alexander T. Archibald, Martyn P. Chipperfield, Sandip Dhomse, Paul T. Griffiths, and John A. Pyle
Atmos. Chem. Phys., 20, 7153–7166, https://doi.org/10.5194/acp-20-7153-2020, https://doi.org/10.5194/acp-20-7153-2020, 2020
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The Montreal Protocol was agreed in 1987 to limit and then stop the production of man-made CFCs, which destroy stratospheric ozone. As a result, the atmospheric abundances of CFCs are now declining in the atmosphere. However, the atmospheric abundance of CFC-11 is not declining as expected under complete compliance with the Montreal Protocol. Using the UM-UKCA chemistry–climate model, we explore the impact of future unregulated production of CFC-11 on ozone recovery.
Hans Brenna, Steffen Kutterolf, Michael J. Mills, and Kirstin Krüger
Atmos. Chem. Phys., 20, 6521–6539, https://doi.org/10.5194/acp-20-6521-2020, https://doi.org/10.5194/acp-20-6521-2020, 2020
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The Los Chocoyos supereruption (84 000 years ago) in Guatemala was one of the largest volcanic events of the last 100 000 years. This eruption released enormous amounts of sulfur, which cooled the climate, as well as chlorine and bromine, which destroyed the ozone in the stratosphere. We have simulated this eruption by using an advanced chemistry–climate model. We found a collapse in the ozone layer lasting more than 10 years, increased surface–UV radiation, and a 30-year climate-cooling period.
Mikhail Sofiev, Rostislav Kouznetsov, Risto Hänninen, and Viktoria F. Sofieva
Atmos. Chem. Phys., 20, 1839–1847, https://doi.org/10.5194/acp-20-1839-2020, https://doi.org/10.5194/acp-20-1839-2020, 2020
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An episode of anomalously low ozone concentrations in the stratosphere over northern Europe occurred on 3–5 November 2018. The 30 % reduction of the ozone layer was predicted by the global chemistry-transport model of the Finnish Meteorological Institute driven by weather forecasts of ECMWF. The reduction was subsequently observed by ozone monitoring satellites. The episode was caused by a storm in the northern Atlantic, which uplifted air from the troposphere to stratosphere.
Martin Dameris, Patrick Jöckel, and Matthias Nützel
Atmos. Chem. Phys., 19, 13759–13771, https://doi.org/10.5194/acp-19-13759-2019, https://doi.org/10.5194/acp-19-13759-2019, 2019
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A chemistry–climate model (CCM) study is performed, investigating the consequences of a constant CFC-11 surface mixing ratio for stratospheric ozone in the future. The total column ozone is particularly affected in both polar regions in winter and spring. It turns out that the calculated ozone changes, especially in the upper stratosphere, are smaller than expected. In this attitudinal region the additional ozone depletion due to the catalysis by reactive chlorine is partly compensated for.
Quentin Errera, Simon Chabrillat, Yves Christophe, Jonas Debosscher, Daan Hubert, William Lahoz, Michelle L. Santee, Masato Shiotani, Sergey Skachko, Thomas von Clarmann, and Kaley Walker
Atmos. Chem. Phys., 19, 13647–13679, https://doi.org/10.5194/acp-19-13647-2019, https://doi.org/10.5194/acp-19-13647-2019, 2019
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BRAM2 is a 13-year reanalysis of the chemical composition from the upper troposphere to the lower mesosphere based on the assimilation of the Microwave Limb Sounder observations where eight species are assimilated: O3, H2O, N2O, HNO3, HCl, ClO, CH3Cl and CO. BRAM2 agrees generally well with independent observations in the middle stratosphere, the polar vortex and the upper troposphere–lower stratosphere but also shows several issues in the model and in the observations.
Ewa M. Bednarz, Amanda C. Maycock, Peter Braesicke, Paul J. Telford, N. Luke Abraham, and John A. Pyle
Atmos. Chem. Phys., 19, 9833–9846, https://doi.org/10.5194/acp-19-9833-2019, https://doi.org/10.5194/acp-19-9833-2019, 2019
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The atmospheric response to the amplitude of 11-year solar cycle in UM-UKCA is separated into the contributions from changes in direct radiative heating and photolysis rates, and the results compared with a control case with both effects included. We find that while the tropical responses are largely additive, this is not necessarily the case in the high latitudes. We suggest that solar-induced changes in ozone are important for modulating the SH dynamical response to the 11-year solar cycle.
Pavle Arsenovic, Alessandro Damiani, Eugene Rozanov, Bernd Funke, Andrea Stenke, and Thomas Peter
Atmos. Chem. Phys., 19, 9485–9494, https://doi.org/10.5194/acp-19-9485-2019, https://doi.org/10.5194/acp-19-9485-2019, 2019
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Low-energy electrons (LEE) are the dominant source of odd nitrogen, which destroys ozone, in the mesosphere and stratosphere in polar winter in the geomagnetically active periods. However, the observed stratospheric ozone anomalies can be reproduced only when accounting for both low- and middle-range energy electrons (MEE) in the chemistry-climate model. Ozone changes may induce further dynamical and thermal changes in the atmosphere. We recommend including both LEE and MEE in climate models.
Franziska Winterstein, Fabian Tanalski, Patrick Jöckel, Martin Dameris, and Michael Ponater
Atmos. Chem. Phys., 19, 7151–7163, https://doi.org/10.5194/acp-19-7151-2019, https://doi.org/10.5194/acp-19-7151-2019, 2019
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The atmospheric concentrations of the anthropogenic greenhouse gas methane are predicted to rise in the future. In this paper we investigate how very strong methane concentrations will impact the atmosphere. We analyse two experiments, one with doubled and one with quintupled methane concentrations and focus on the rapid atmospheric changes before the ocean adjusts to the induced
forcing. In particular these are changes in temperature, ozone, the hydroxyl radical and stratospheric water vapour.
Mengchu Tao, Paul Konopka, Felix Ploeger, Xiaolu Yan, Jonathon S. Wright, Mohamadou Diallo, Stephan Fueglistaler, and Martin Riese
Atmos. Chem. Phys., 19, 6509–6534, https://doi.org/10.5194/acp-19-6509-2019, https://doi.org/10.5194/acp-19-6509-2019, 2019
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This paper examines the annual and interannual variations as well as long-term trend of modeled stratospheric water vapor with a Lagrangian chemical transport model driven by ERA-I, MERRA-2 and JRA-55. We find reasonable consistency among the annual cycle, QBO and the variabilities induced by ENSO and volcanic aerosols. The main discrepancies are linked to the differences in reanalysis upwelling rates in the lower stratosphere. The trends are sensitive to the reanalyses that drives the model.
Felix Ploeger, Bernard Legras, Edward Charlesworth, Xiaolu Yan, Mohamadou Diallo, Paul Konopka, Thomas Birner, Mengchu Tao, Andreas Engel, and Martin Riese
Atmos. Chem. Phys., 19, 6085–6105, https://doi.org/10.5194/acp-19-6085-2019, https://doi.org/10.5194/acp-19-6085-2019, 2019
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We analyse the change in the circulation of the middle atmosphere based on current generation meteorological reanalysis data sets. We find that long-term changes from 1989 to 2015 are similar for the chosen reanalyses, mainly resembling the forced response in climate model simulations to climate change. For shorter periods circulation changes are less robust, and the representation of decadal variability appears to be a major uncertainty for modelling the circulation of the middle atmosphere.
Lucien Froidevaux, Douglas E. Kinnison, Ray Wang, John Anderson, and Ryan A. Fuller
Atmos. Chem. Phys., 19, 4783–4821, https://doi.org/10.5194/acp-19-4783-2019, https://doi.org/10.5194/acp-19-4783-2019, 2019
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This work evaluates two versions of a 3-D global model of upper-atmospheric composition for recent decades. The two versions differ mainly in their dynamical (wind) constraints. Model–data differences, variability, and trends in five gases (ozone, H2O, HCl, HNO3, and N2O) are compared. While the match between models and observations is impressive, a few areas of discrepancy are noted. This work also updates trends in composition based on recent satellite-based measurements (through 2018).
Thomas von Clarmann and Sören Johansson
Atmos. Chem. Phys., 18, 15363–15386, https://doi.org/10.5194/acp-18-15363-2018, https://doi.org/10.5194/acp-18-15363-2018, 2018
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This review article compiles the characteristics of the gas chlorine nitrate and discusses its role in atmospheric chemistry. Chlorine nitrate is a reservoir of both stratospheric chlorine and nitrogen. Formation and sink processes are discussed, as well as spectral features and spectroscopic studies. Remote sensing, fluorescence, and mass spectroscopic measurement techniques are introduced, and global distributions and the annual cycle are discussed in the context of chlorine de-/activation.
Laura Thölix, Alexey Karpechko, Leif Backman, and Rigel Kivi
Atmos. Chem. Phys., 18, 15047–15067, https://doi.org/10.5194/acp-18-15047-2018, https://doi.org/10.5194/acp-18-15047-2018, 2018
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We analyse the impact of water vapour (WV) on Arctic ozone loss and find the strongest impact during intermediately cold stratospheric winters when chlorine activation increases with increasing PSCs and WV. In colder winters the impact is limited because chlorine activation becomes complete at relatively low WV values, so further addition of WV does not affect ozone loss. Our results imply that improved simulations of WV are needed for more reliable projections of ozone layer recovery.
Alina Fiehn, Birgit Quack, Irene Stemmler, Franziska Ziska, and Kirstin Krüger
Atmos. Chem. Phys., 18, 11973–11990, https://doi.org/10.5194/acp-18-11973-2018, https://doi.org/10.5194/acp-18-11973-2018, 2018
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Oceanic very short-lived substances, VSLS, contribute to stratospheric halogen loading and ozone depletion. We created bromoform emission inventories with monthly resolution for the tropical Indian Ocean and west Pacific and modeled the atmospheric transport of bromoform with the particle dispersion model FLEXPART/ERA-Interim. Results underline that the seasonal and regional stratospheric bromine entrainment critically depends on the seasonality and spatial distribution of the VSLS emissions.
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Short summary
Transport circulation in the stratosphere is important for the distribution of tracers, but its strength is hard to measure. Mean transport times can be inferred from observations of trace gases with certain properties, such as sulfur hexafluoride (SF6). However, this gas has a chemical sink in the high atmosphere, which can lead to substantial biases in inferred transport times. In this paper we present a method to correct mean transport times derived from SF6 for the effects of chemical sinks.
Transport circulation in the stratosphere is important for the distribution of tracers, but its...
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