Articles | Volume 10, issue 1
https://doi.org/10.5194/acp-10-121-2010
© Author(s) 2010. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/acp-10-121-2010
© Author(s) 2010. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
11 Jan 2010
Annual cycle of ozone at and above the tropical tropopause: observations versus simulations with the Chemical Lagrangian Model of the Stratosphere (CLaMS)
P. Konopka
Forschungszentrum Jülich (ICG-1: Stratosphere), Jülich, Germany
J.-U. Grooß
Forschungszentrum Jülich (ICG-1: Stratosphere), Jülich, Germany
G. Günther
Forschungszentrum Jülich (ICG-1: Stratosphere), Jülich, Germany
F. Ploeger
Forschungszentrum Jülich (ICG-1: Stratosphere), Jülich, Germany
R. Pommrich
Forschungszentrum Jülich (ICG-1: Stratosphere), Jülich, Germany
R. Müller
Forschungszentrum Jülich (ICG-1: Stratosphere), Jülich, Germany
N. Livesey
Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
Related subject area
Subject: Gases | Research Activity: Atmospheric Modelling and Data Analysis | Altitude Range: Stratosphere | Science Focus: Chemistry (chemical composition and reactions)
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
Analysis of a newly homogenised ozonesonde dataset from Lauder, New Zealand
Correction of stratospheric age of air (AoA) derived from sulfur hexafluoride (SF6) for the effect of chemical sinks
The impact of dehydration and extremely low HCl values in the Antarctic stratospheric vortex in mid-winter on ozone loss in spring
On the atmospheric budget of ethylene dichloride and its impact on stratospheric chlorine and ozone (2002–2020)
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
The representation of solar cycle signals in stratospheric ozone – Part 2: Analysis of global models
Investigating the yield of H2O and H2 from methane oxidation in the stratosphere
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.
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.
Hella Garny, Roland Eichinger, Johannes C. Laube, Eric A. Ray, Gabriele P. Stiller, Harald Bönisch, Laura Saunders, and Marianna Linz
Atmos. Chem. Phys., 24, 4193–4215, https://doi.org/10.5194/acp-24-4193-2024, https://doi.org/10.5194/acp-24-4193-2024, 2024
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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.
Yiran Zhang-Liu, Rolf Müller, Jens-Uwe Grooß, Sabine Robrecht, Bärbel Vogel, Abdul Mannan Zafar, and Ralph Lehmann
EGUsphere, https://doi.org/10.5194/egusphere-2024-671, https://doi.org/10.5194/egusphere-2024-671, 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) taking into account dehydration in the Antarctic winter vortex and (3) considering the observed (but unexplained) depletion of HCl in mid-winter in the Antartic vortex. throughout Antarctic winter.
Ryan Hossaini, David Sherry, Zihao Wang, Martyn Chipperfield, Wuhu Feng, David Oram, Karina Adcock, Stephen Montzka, Isobel Simpson, Andrea Mazzeo, Amber Leeson, Elliot Atlas, and Charles C.-K. Chou
EGUsphere, https://doi.org/10.5194/egusphere-2024-560, https://doi.org/10.5194/egusphere-2024-560, 2024
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Ethylene dichloride (EDC) is an industrial chemical used to produce polyvinyl chloride (PVC). We analysed EDC production data to estimate global EDC emissions (2002 to 2020). The emissions were included in an atmospheric model and evaluated by comparing simulated EDC to EDC measurements in the troposphere. We show EDC contributes ozone-depleting chlorine to the stratosphere and this has increased with increasing EDC emissions. EDC’s impact on stratospheric ozone is currently small, but non-zero.
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.
Amanda C. Maycock, Katja Matthes, Susann Tegtmeier, Hauke Schmidt, Rémi Thiéblemont, Lon Hood, Hideharu Akiyoshi, Slimane Bekki, Makoto Deushi, Patrick Jöckel, Oliver Kirner, Markus Kunze, Marion Marchand, Daniel R. Marsh, Martine Michou, David Plummer, Laura E. Revell, Eugene Rozanov, Andrea Stenke, Yousuke Yamashita, and Kohei Yoshida
Atmos. Chem. Phys., 18, 11323–11343, https://doi.org/10.5194/acp-18-11323-2018, https://doi.org/10.5194/acp-18-11323-2018, 2018
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The 11-year solar cycle is an important driver of climate variability. Changes in incoming solar ultraviolet radiation affect atmospheric ozone, which in turn influences atmospheric temperatures. Constraining the impact of the solar cycle on ozone is therefore important for understanding climate variability. This study examines the representation of the solar influence on ozone in numerical models used to simulate past and future climate. We highlight important differences among model datasets.
Franziska Frank, Patrick Jöckel, Sergey Gromov, and Martin Dameris
Atmos. Chem. Phys., 18, 9955–9973, https://doi.org/10.5194/acp-18-9955-2018, https://doi.org/10.5194/acp-18-9955-2018, 2018
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It is frequently assumed that one methane molecule produces two water molecules. Applying various modeling concepts, we find that the yield of water from methane is vertically not constantly 2. In the upper stratosphere and lower mesosphere, transport of intermediate H2 molecules even led to a yield greater than 2. We conclude that for a realistic chemical source of stratospheric water vapor, one must also take other sources (H2), intermediates and the chemical removal of water into account.
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