Articles | Volume 13, issue 8
Research article 29 Apr 2013
Research article | 29 Apr 2013
Evolution of Antarctic ozone in September–December predicted by CCMVal-2 model simulations for the 21st century
J. M. Siddaway et al.
No articles found.
Alexander D. Fraser, Robert A. Massom, Mark S. Handcock, Phillip Reid, Kay I. Ohshima, Marilyn N. Raphael, Jessica Cartwright, Andrew R. Klekociuk, Zhaohui Wang, and Richard Porter-Smith
The Cryosphere Discuss.,
Preprint under review for TCShort summary
Landfast ice is sea ice that remains stationary by attaching to Antarctica’s coastline and grounded icebergs. Although a variable feature, landfast ice exerts influence on key coastal processes involving pack ice, the ice sheet, ocean and atmosphere, and is of ecological importance. We present a first analysis of change in landfast-ice over an 18 y period, and quantify trends (−0.19 ± 0.18 %/year). This analysis forms a reference of landfast ice extent and variability for use in other studies.
William R. Hobbs, Andrew R. Klekociuk, and Yuhang Pan
Atmos. Chem. Phys., 20, 14757–14768,Short summary
Reanalysis products are an invaluable tool for representing variability and long-term trends in regions with limited in situ data. However, validation of these products is difficult because of that lack of station data. Here we present a novel assessment of eight reanalyses over the polar Southern Ocean, leveraging the close relationship between trends in sea ice cover and surface air temperature, that provides clear guidance on the most reliable product for Antarctic research.
Camilla K. Crockart, Tessa R. Vance, Alexander D. Fraser, Nerilie J. Abram, Alison S. Criscitiello, Mark A. J. Curran, Vincent Favier, Ailie J. E. Gallant, Helle A. Kjær, Andrew R. Klekociuk, Lenneke M. Jong, Andrew D. Moy, Christopher T. Plummer, Paul T. Vallelonga, Jonathon Wille, and Lingwei Zhang
Clim. Past Discuss.,
Revised manuscript under review for CPShort summary
Preliminary analyses of the annual sea salt concentrations and snowfall accumulation in a new East Antarctic ice core, Mount Brown South. We compare this record with an updated Law Dome (Dome Summit South site) ice core record over the period 1975–2016. The Mount Brown South record preserves a stronger and inverse signal for the El Niño Southern Oscillation (in austral winter and spring) compared to the Law Dome record (in summer).
W. John R. French, Andrew R. Klekociuk, and Frank J. Mulligan
Atmos. Chem. Phys., 20, 8691–8708,Short summary
We explore a quasi-quadrennial oscillation (QQO; 3–4 K amplitude, ~ 4-year period) in mesopause region temperatures observed in 24 years of hydroxyl airglow measurements over Davis, Antarctica (68° S, 78° E). Correlation and composite analysis using meteorological reanalysis and satellite data reveals complex patterns on the QQO timescale in both hemispheres. Modulation of the meridional circulation, linked to the propagation of gravity waves, plays a significant role in producing the QQO response.
W. John R. French, Frank J. Mulligan, and Andrew R. Klekociuk
Atmos. Chem. Phys., 20, 6379–6394,Short summary
In this study, we analyse 24 years of atmospheric temperatures from the mesopause region (~87 km altitude) derived from ground-based spectrometer observations of hydroxyl airglow at Davis station, Antarctica (68° S, 78° E). These data are used to quantify the effect of the solar cycle and the long-term trend due to increasing greenhouse gas emissions on the atmosphere at this level. A record-low winter-average temperature is reported for 2018 and comparisons are made with satellite observations.
Julie M. Nicely, Bryan N. Duncan, Thomas F. Hanisco, Glenn M. Wolfe, Ross J. Salawitch, Makoto Deushi, Amund S. Haslerud, Patrick Jöckel, Béatrice Josse, Douglas E. Kinnison, Andrew Klekociuk, Michael E. Manyin, Virginie Marécal, Olaf Morgenstern, Lee T. Murray, Gunnar Myhre, Luke D. Oman, Giovanni Pitari, Andrea Pozzer, Ilaria Quaglia, Laura E. Revell, Eugene Rozanov, Andrea Stenke, Kane Stone, Susan Strahan, Simone Tilmes, Holger Tost, Daniel M. Westervelt, and Guang Zeng
Atmos. Chem. Phys., 20, 1341–1361,Short summary
Differences in methane lifetime among global models are large and poorly understood. We use a neural network method and simulations from the Chemistry Climate Model Initiative to quantify the factors influencing methane lifetime spread among models and variations over time. UV photolysis, tropospheric ozone, and nitrogen oxides drive large model differences, while the same factors plus specific humidity contribute to a decreasing trend in methane lifetime between 1980 and 2015.
Yuke Wang, Valerii Shulga, Gennadi Milinevsky, Aleksey Patoka, Oleksandr Evtushevsky, Andrew Klekociuk, Wei Han, Asen Grytsai, Dmitry Shulga, Valery Myshenko, and Oleksandr Antyufeyev
Atmos. Chem. Phys., 19, 10303–10317,Short summary
The major sudden stratospheric warming (SSW) dramatically changed atmospheric conditions. This event is accompanied by a sharp increase in the polar stratosphere temperature, zonal wind reverse, and strong changes in the polar mesosphere. These changes affect even the midlatitude mesosphere, which is not widely covered by observations. Our newly installed microwave radiometer allowed for studying mesospheric zonal wind and CO variations to understand the SSW 2018 effects at midlatitudes.
Blanca Ayarzagüena, Lorenzo M. Polvani, Ulrike Langematz, Hideharu Akiyoshi, Slimane Bekki, Neal Butchart, Martin Dameris, Makoto Deushi, Steven C. Hardiman, Patrick Jöckel, Andrew Klekociuk, Marion Marchand, Martine Michou, Olaf Morgenstern, Fiona M. O'Connor, Luke D. Oman, David A. Plummer, Laura Revell, Eugene Rozanov, David Saint-Martin, John Scinocca, Andrea Stenke, Kane Stone, Yousuke Yamashita, Kohei Yoshida, and Guang Zeng
Atmos. Chem. Phys., 18, 11277–11287,Short summary
Stratospheric sudden warmings (SSWs) are natural major disruptions of the polar stratospheric circulation that also affect surface weather. In the literature there are conflicting claims as to whether SSWs will change in the future. The confusion comes from studies using different models and methods. Here we settle the question by analysing 12 models with a consistent methodology, to show that no robust changes in frequency and other features are expected over the 21st century.
Jesse W. Greenslade, Simon P. Alexander, Robyn Schofield, Jenny A. Fisher, and Andrew K. Klekociuk
Atmos. Chem. Phys., 17, 10269–10290,Short summary
An analysis of data from ozonesondes released at three southern oceanic sites shows the impact of stratospheric ozone in this region. Using a novel method of transport classification, this work estimates the seasonality and quantity of stratospherically sourced ozone. We find that ozone is transported most frequently in summer due to regional-scale low-pressure weather systems. We also estimate a stratospheric ozone source of 2.0–3.3 Tg/year over three Southern Ocean regions.
Chris S.~M. Turney, Andrew Klekociuk, Christopher J. Fogwill, Violette Zunz, Hugues Goosse, Claire L. Parkinson, Gilbert Compo, Matthew Lazzara, Linda Keller, Rob Allan, Jonathan G. Palmer, Graeme Clark, and Ezequiel Marzinelli
The Cryosphere Discuss.,
Revised manuscript not acceptedShort summary
We demonstrate that a mid-twentieth century decrease in geopotential height in the southwest Pacific marks a Rossby wave response to equatorial Pacific warming, leading to enhanced easterly airflow off George V Land. Our results suggest that in contrast to ozone hole-driven changes in the Amundsen Sea, the 1979–2015 increase in sea ice extent off George V Land may be in response to reduced northward Ekman drift and enhanced (near-coast) production as a consequence of low latitude forcing.
Iain M. Reid, Andrew J. Spargo, Jonathan M. Woithe, Andrew R. Klekociuk, Joel P. Younger, and Gulamabas G. Sivjee
Ann. Geophys., 35, 567–582,Short summary
We measured temperatures in the atmosphere at heights near 90 km using nightglow emissions and compared them with satellite measurements and with measurements made with a meteor radar. We found good agreement between the techniques, which improved when we used the meteor radar and satellite data to measure densities at two heights separated by about 10 km to estimate the nightglow emission height.
Asen Grytsai, Andrew Klekociuk, Gennadi Milinevsky, Oleksandr Evtushevsky, and Kane Stone
Atmos. Chem. Phys., 17, 1741–1758,Short summary
Twenty years ago we discovered that the ozone hole shape is asymmetric. This asymmetry is minimum over the Weddell Sea region and maximum over the Ross Sea area. Later we detected that the position of the ozone minimum is shifting east. We have continued to follow this event, and a couple years ago we revealed that the shift is slowing down and starting to move back. We connect all this movement with ozone hole increase; since 2000 the ozone layer has been stabilizing and recently recovering.
Kane A. Stone, Olaf Morgenstern, David J. Karoly, Andrew R. Klekociuk, W. John French, N. Luke Abraham, and Robyn Schofield
Atmos. Chem. Phys., 16, 2401–2415,Short summary
This paper describes the set-up and evaluation of the Australian Community Climate and Earth System Simulator – chemistry-climate model.
Emphasis is placed on the Antarctic ozone hole, which is very important considering its role modulating Southern Hemisphere surface climate. While the model simulates the global distribution of ozone well, there is a disparity in the vertical location of springtime ozone depletion over Antarctica, highlighting important areas for future development.
Emphasis is placed on the Antarctic ozone hole, which is very important considering its role modulating Southern Hemisphere surface climate. While the model simulates the global distribution of ozone well, there is a disparity in the vertical location of springtime ozone depletion over Antarctica, highlighting important areas for future development.
R. S. Humphries, A. R. Klekociuk, R. Schofield, M. Keywood, J. Ward, and S. R. Wilson
Atmos. Chem. Phys., 16, 2185–2206,Short summary
This work represents the first observational study of atmospheric sub-micron aerosols in the East Antarctic pack ice region and found springtime aerosol concentrations were higher than any observed elsewhere in the Antarctic and Southern Ocean region. Further analysis suggested these aerosols formed in the Antarctic free troposphere. Their subsequent transport to the Southern Ocean, as suggest by trajectory analyses, could help to reduce the discrepancy in the radiative budget in the region.
C. S. M. Turney, C. J. Fogwill, A. R. Klekociuk, T. D. van Ommen, M. A. J. Curran, A. D. Moy, and J. G. Palmer
The Cryosphere, 9, 2405–2415,Short summary
Recent trends in ocean circulation, sea ice and climate over the Southern Ocean and Antarctica are highly complex. Here we report a new snow core from the South Pole alongside reanalysis of 20th century global atmospheric circulation. We demonstrate for the first time that atmospheric pressure anomalies in the mid-latitudes act as "gatekeepers" to meridional exchange over continental Antarctica, modulated by the tropical Pacific, with potentially significant impacts on surface mass balance.
R. S. Humphries, R. Schofield, M. D. Keywood, J. Ward, J. R. Pierce, C. M. Gionfriddo, M. T. Tate, D. P. Krabbenhoft, I. E. Galbally, S. B. Molloy, A. R. Klekociuk, P. V. Johnston, K. Kreher, A. J. Thomas, A. D. Robinson, N. R. P. Harris, R. Johnson, and S. R. Wilson
Atmos. Chem. Phys., 15, 13339–13364,Short summary
An atmospheric new particle formation event that was observed in the pristine East Antarctic pack ice during a springtime voyage in 2012 is characterised in terms of formation and growth rates. Known nucleation mechanisms (e.g. those involving sulfate, iodine and organics) were unable to explain observations; however, correlations with total gaseous mercury were found, leading to the suggestion of a possible mercury-driven nucleation mechanism not previously described.
P. Ciais, A. J. Dolman, A. Bombelli, R. Duren, A. Peregon, P. J. Rayner, C. Miller, N. Gobron, G. Kinderman, G. Marland, N. Gruber, F. Chevallier, R. J. Andres, G. Balsamo, L. Bopp, F.-M. Bréon, G. Broquet, R. Dargaville, T. J. Battin, A. Borges, H. Bovensmann, M. Buchwitz, J. Butler, J. G. Canadell, R. B. Cook, R. DeFries, R. Engelen, K. R. Gurney, C. Heinze, M. Heimann, A. Held, M. Henry, B. Law, S. Luyssaert, J. Miller, T. Moriyama, C. Moulin, R. B. Myneni, C. Nussli, M. Obersteiner, D. Ojima, Y. Pan, J.-D. Paris, S. L. Piao, B. Poulter, S. Plummer, S. Quegan, P. Raymond, M. Reichstein, L. Rivier, C. Sabine, D. Schimel, O. Tarasova, R. Valentini, R. Wang, G. van der Werf, D. Wickland, M. Williams, and C. Zehner
Biogeosciences, 11, 3547–3602,
S. P. Alexander, D. J. Murphy, and A. R. Klekociuk
Atmos. Chem. Phys., 13, 3121–3132,
Related subject area
Subject: Gases | Research Activity: Atmospheric Modelling | Altitude Range: Stratosphere | Science Focus: Physics (physical properties and processes)The stratospheric Brewer–Dobson circulation inferred from age of air in the ERA5 reanalysisSimulations of anthropogenic bromoform indicate high emissions at the coast of East AsiaSensitivity of stratospheric water vapour to variability in tropical tropopause temperatures and large-scale transportTechnical note: Lowermost-stratosphere moist bias in ECMWF IFS model diagnosed from airborne GLORIA observations during winter–spring 2016The response of stratospheric water vapor to climate change driven by different forcing agentsInfluence of convection on stratospheric water vapor in the North American monsoon regionThe 2019 Raikoke volcanic eruption: Part 1 Dispersion model simulations and satellite retrievals of volcanic sulfur dioxideElectricity savings and greenhouse gas emission reductions from global phase-down of hydrofluorocarbonsImpact of convectively lofted ice on the seasonal cycle of water vapor in the tropical tropopause layerSimulating the atmospheric response to the 11-year solar cycle forcing with the UM-UKCA model: the role of detection method and natural variabilityTransport of trace gases via eddy shedding from the Asian summer monsoon anticyclone and associated impacts on ozone heating ratesDetectability of the impacts of ozone-depleting substances and greenhouse gases upon stratospheric ozone accounting for nonlinearities in historical forcingsMulti-decadal records of stratospheric composition and their relationship to stratospheric circulation changeBrominated VSLS and their influence on ozone under a changing climateContribution of different processes to changes in tropical lower-stratospheric water vapor in chemistry–climate modelsQuantifying pollution transport from the Asian monsoon anticyclone into the lower stratosphereA new time-independent formulation of fractional releaseThe millennium water vapour drop in chemistry–climate model simulationsImpact of major volcanic eruptions on stratospheric water vapourVariability of water vapour in the Arctic stratosphereOn the hiatus in the acceleration of tropical upwelling since the beginning of the 21st centuryTrends in peroxyacetyl nitrate (PAN) in the upper troposphere and lower stratosphere over southern Asia during the summer monsoon season: regional impactsSpatial regression analysis on 32 years of total column ozone dataOzone seasonality above the tropical tropopause: reconciling the Eulerian and Lagrangian perspectives of transport processesModeling upper tropospheric and lower stratospheric water vapor anomaliesAssessment of the interannual variability and influence of the QBO and upwelling on tracer–tracer distributions of N2O and O3 in the tropical lower stratosphereOCS photolytic isotope effects from first principles: sulfur and carbon isotopes, temperature dependence and implications for the stratosphereOn the relationship between total ozone and atmospheric dynamics and chemistry at mid-latitudes – Part 2: The effects of the El Niño/Southern Oscillation, volcanic eruptions and contributions of atmospheric dynamics and chemistry to long-term total ozone changesRelationships between Brewer-Dobson circulation, double tropopauses, ozone and stratospheric water vapourSimulation of stratospheric water vapor and trends using three reanalysesClimatological perspectives of air transport from atmospheric boundary layer to tropopause layer over Asian monsoon regions during boreal summer inferred from Lagrangian approachSolar response in tropical stratospheric ozone: a 3-D chemical transport model study using ERA reanalysesGeomagnetic activity related NOx enhancements and polar surface air temperature variability in a chemistry climate model: modulation of the NAM indexForecasts and assimilation experiments of the Antarctic ozone hole 2008Extreme events in total ozone over Arosa – Part 2: Fingerprints of atmospheric dynamics and chemistry and effects on mean values and long-term changesTechnical Note: Trend estimation from irregularly sampled, correlated dataModeling the transport of very short-lived substances into the tropical upper troposphere and lower stratosphere
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,Short summary
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.
Josefine Maas, Susann Tegtmeier, Yue Jia, Birgit Quack, Jonathan V. Durgadoo, and Arne Biastoch
Atmos. Chem. Phys., 21, 4103–4121,Short summary
Cooling-water disinfection at coastal power plants is a known source of atmospheric bromoform. A large source of anthropogenic bromoform is the industrial regions in East Asia. In current bottom-up flux estimates, these anthropogenic emissions are missing, underestimating the global air–sea flux of bromoform. With transport simulations, we show that by including anthropogenic bromoform from cooling-water treatment, the bottom-up flux estimates significantly improve in East and Southeast Asia.
Jacob W. Smith, Peter H. Haynes, Amanda C. Maycock, Neal Butchart, and Andrew C. Bushell
Atmos. Chem. Phys., 21, 2469–2489,Short summary
This paper informs realistic simulation of stratospheric water vapour by clearly attributing each of the two key influences on water vapour entry to the stratosphere. Presenting modified trajectory models, the results of this paper show temperatures dominate on annual and inter-annual variations; however, transport has a significant effect in reducing the annual cycle maximum. Furthermore, sub-seasonal variations in temperature have an important overall influence.
Wolfgang Woiwode, Andreas Dörnbrack, Inna Polichtchouk, Sören Johansson, Ben Harvey, Michael Höpfner, Jörn Ungermann, and Felix Friedl-Vallon
Atmos. Chem. Phys., 20, 15379–15387,Short summary
The lowermost-stratosphere moist bias in ECMWF analyses and 12 h forecasts is diagnosed for the Arctic winter-spring 2016 period by using two-dimensional GLORIA water vapor observations. The bias is already present in the initial conditions (i.e., the analyses), and sensitivity forecasts on time scales of < 12 h show hardly any sensitivity to modified spatial resolution and output frequency.
Xun Wang and Andrew E. Dessler
Atmos. Chem. Phys., 20, 13267–13282,Short summary
We investigate the response of stratospheric water vapor (SWV) to different forcing agents, including greenhouse gases and aerosols. For most forcing agents, the SWV response is dominated by a slow response, which is coupled to surface temperature changes and exhibits a similar sensitivity to the surface temperature across all forcing agents. The fast SWV adjustment due to forcing is important when the forcing agent directly heats the cold-point region, e.g., black carbon.
Wandi Yu, Andrew E. Dessler, Mijeong Park, and Eric J. Jensen
Atmos. Chem. Phys., 20, 12153–12161,Short summary
The stratospheric water vapor mixing ratio over North America (NA) region is up to ~ 1 ppmv higher when deep convection occurs. We find substantial consistency in the interannual variations of NA water vapor anomaly and deep convection and explain both the summer seasonal cycle and interannual variability of the convective moistening efficiency. We show that the NA anticyclone and tropical upper tropospheric temperature determine how much deep convection moistens the lower stratosphere.
Johannes de Leeuw, Anja Schmidt, Claire S. Witham, Nicolas Theys, Isabelle A. Taylor, Roy G. Grainger, Richard J. Pope, Jim Haywood, Martin Osborne, and Nina I. Kristiansen
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
Using the NAME dispersion model in combination with high-resolution SO2 satellite data from TROPOMI we investigate the dispersion of volcanic SO2 from the 2019 Raikoke eruption. NAME accurately simulates the dispersion of SO2 during the first 2–3 weeks after the eruption and we demonstrate the potential of using high-resolution satellite data to identify and rectify limitations in dispersion models, which will ultimately help to improve efforts to forecast the dispersion of volcanic clouds.
Pallav Purohit, Lena Höglund-Isaksson, John Dulac, Nihar Shah, Max Wei, Peter Rafaj, and Wolfgang Schöpp
Atmos. Chem. Phys., 20, 11305–11327,Short summary
This study shows that if energy efficiency improvements in cooling technologies are addressed simultaneously with a phase-down of hydrofluorocarbons (HFCs), not only will global warming be mitigated through the elimination of HFCs but also by saving about a fifth of future global electricity consumption. This means preventing between 411 and 631 Pg CO2 equivalent of greenhouse gases between today and 2100, thereby offering a significant contribution towards staying well below 2 °C warming.
Xun Wang, Andrew E. Dessler, Mark R. Schoeberl, Wandi Yu, and Tao Wang
Atmos. Chem. Phys., 19, 14621–14636,Short summary
We use a trajectory model to diagnose mechanisms that produce the observed and modeled tropical lower stratospheric water vapor seasonal cycle. We confirm that the seasonal cycle of water vapor is primarily determined by the seasonal cycle of tropical tropopause layer (TTL) temperatures. However, between 10° N and 40° N, we find that evaporation of convective ice in the TTL plays a key role contributing to the water vapor seasonal cycle there. The Asian monsoon region is the most important region.
Ewa M. Bednarz, Amanda C. Maycock, Paul J. Telford, Peter Braesicke, N. Luke Abraham, and John A. Pyle
Atmos. Chem. Phys., 19, 5209–5233,Short summary
Following model improvements, the atmospheric response to the 11-year solar cycle forcing simulated in the UM-UKCA chemistry–climate model is discussed for the first time. In contrast to most previous studies in the literature, we compare the results diagnosed using both a composite and a MLR methodology, and we show that apparently different signals can be diagnosed in the troposphere. In addition, we look at the role of internal atmospheric variability for the detection of the solar response.
Suvarna Fadnavis, Chaitri Roy, Rajib Chattopadhyay, Christopher E. Sioris, Alexandru Rap, Rolf Müller, K. Ravi Kumar, and Raghavan Krishnan
Atmos. Chem. Phys., 18, 11493–11506,Short summary
Rapid industrialization, traffic growth and urbanization resulted in a significant increase in the tropospheric trace gases over Asia. There is global concern about rising levels of these trace gases. The monsoon convection transports these gases to the upper-level-anticyclone. In this study, we show transport of these gases to the extratropics via eddy-shedding from the anticyclone. We also deliberate on changes in ozone heating rates due to the transport of Asian trace gases.
Justin Bandoro, Susan Solomon, Benjamin D. Santer, Douglas E. Kinnison, and Michael J. Mills
Atmos. Chem. Phys., 18, 143–166,Short summary
We studied the attribution of stratospheric ozone changes and identified similarities between observations and human fingerprints from both emissions of ozone-depleting substances (ODSs) and greenhouse gases (GHGs). We developed an improvement on the traditional pattern correlation method that accounts for nonlinearities in the climate forcing time evolution. Use of the latter resulted in increased S / N ratios for the ODS fingerprint. The GHG fingerprint was not identifiable.
Anne R. Douglass, Susan E. Strahan, Luke D. Oman, and Richard S. Stolarski
Atmos. Chem. Phys., 17, 12081–12096,Short summary
Data records from instruments on satellites and on the ground are compared with a simulation for 1980–2016 that is made using winds and temperatures that are derived from measurements. The simulation tracks the observations faithfully after about 2000, but there are systematic errors for earlier years. Scientists must take this into account when trying to detect and quantify changes in the stratospheric circulation that are caused by climate change.
Stefanie Falk, Björn-Martin Sinnhuber, Gisèle Krysztofiak, Patrick Jöckel, Phoebe Graf, and Sinikka T. Lennartz
Atmos. Chem. Phys., 17, 11313–11329,Short summary
Brominated very short-lived source gases (VSLS) contribute significantly to the tropospheric and stratospheric bromine loading. We find an increase of future ocean–atmosphere flux of brominated VSLS of 8–10 % compared to present day. A decrease in the tropospheric mixing ratios of VSLS and an increase in the lower stratosphere are attributed to changes in atmospheric chemistry and transport. Bromine impact on stratospheric ozone at the end of the 21st century is reduced compared to present day.
Kevin M. Smalley, Andrew E. Dessler, Slimane Bekki, Makoto Deushi, Marion Marchand, Olaf Morgenstern, David A. Plummer, Kiyotaka Shibata, Yousuke Yamashita, and Guang Zeng
Atmos. Chem. Phys., 17, 8031–8044,Short summary
This paper explains a new way to evaluate simulated lower-stratospheric water vapor. We use a multivariate linear regression to predict 21st century lower stratospheric water vapor within 12 chemistry climate models using tropospheric warming, the Brewer–Dobson circulation, and the quasi-biennial oscillation as predictors. This methodology produce strong fits to simulated water vapor, and potentially represents a superior method to evaluate model trends in lower-stratospheric water vapor.
Felix Ploeger, Paul Konopka, Kaley Walker, and Martin Riese
Atmos. Chem. Phys., 17, 7055–7066,Short summary
Pollution transport from the surface to the stratosphere within the Asian summer monsoon circulation may cause harmful effects on stratospheric chemistry and climate. We investigate air mass transport from the monsoon anticyclone into the stratosphere, combining model simulations with satellite trace gas measurements. We show evidence for two transport pathways from the monsoon: (i) into the tropical stratosphere and (ii) into the Northern Hemisphere extratropical lower stratosphere.
Jennifer Ostermöller, Harald Bönisch, Patrick Jöckel, and Andreas Engel
Atmos. Chem. Phys., 17, 3785–3797,Short summary
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.
Sabine Brinkop, Martin Dameris, Patrick Jöckel, Hella Garny, Stefan Lossow, and Gabriele Stiller
Atmos. Chem. Phys., 16, 8125–8140,Short summary
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.
Michael Löffler, Sabine Brinkop, and Patrick Jöckel
Atmos. Chem. Phys., 16, 6547–6562,Short summary
After the two major volcanic eruptions of El Chichón in Mexico in 1982 and Mount Pinatubo on the Philippines in 1991, stratospheric water vapour is significantly increased. This results from increased stratospheric heating rates due to volcanic aerosol and the subsequent changes in stratospheric and tropopause temperatures in the tropics. The tropical vertical advection and the South Asian summer monsoon are identified as important sources for the additional water vapour in the stratosphere.
Laura Thölix, Leif Backman, Rigel Kivi, and Alexey Yu. Karpechko
Atmos. Chem. Phys., 16, 4307–4321,
J. Aschmann, J. P. Burrows, C. Gebhardt, A. Rozanov, R. Hommel, M. Weber, and A. M. Thompson
Atmos. Chem. Phys., 14, 12803–12814,Short summary
This study compares observations and simulation results of ozone in the lower tropical stratosphere. It shows that ozone in this region decreased from 1985 up to about 2002, which is consistent with an increase in tropical upwelling predicted by climate models. However, the decrease effectively stops after 2002, indicating that significant changes in tropical upwelling have occurred. The most important factor appears to be that the vertical ascent in the tropics is no longer accelerating.
S. Fadnavis, M. G. Schultz, K. Semeniuk, A. S. Mahajan, L. Pozzoli, S. Sonbawne, S. D. Ghude, M. Kiefer, and E. Eckert
Atmos. Chem. Phys., 14, 12725–12743,Short summary
The Asian summer monsoon transports pollutants from local emission sources to the upper troposphere and lower stratosphere (UTLS). The increasing trend of these pollutants may have climatic impact. This study addresses the impact of convectively lifted Indian and Chinese emissions on the ULTS. Sensitivity experiments with emission changes in particular regions show that Chinese emissions have a greater impact on the concentrations of NOY species than Indian emissions.
J. S. Knibbe, R. J. van der A, and A. T. J. de Laat
Atmos. Chem. Phys., 14, 8461–8482,
M. Abalos, F. Ploeger, P. Konopka, W. J. Randel, and E. Serrano
Atmos. Chem. Phys., 13, 10787–10794,
M. R. Schoeberl, A. E. Dessler, and T. Wang
Atmos. Chem. Phys., 13, 7783–7793,
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,
J. A. Schmidt, M. S. Johnson, S. Hattori, N. Yoshida, S. Nanbu, and R. Schinke
Atmos. Chem. Phys., 13, 1511–1520,
H. E. Rieder, L. Frossard, M. Ribatet, J. Staehelin, J. A. Maeder, S. Di Rocco, A. C. Davison, T. Peter, P. Weihs, and F. Holawe
Atmos. Chem. Phys., 13, 165–179,
J. M. Castanheira, T. R. Peevey, C. A. F. Marques, and M. A. Olsen
Atmos. Chem. Phys., 12, 10195–10208,
M. R. Schoeberl, A. E. Dessler, and T. Wang
Atmos. Chem. Phys., 12, 6475–6487,
B. Chen, X. D. Xu, S. Yang, and T. L. Zhao
Atmos. Chem. Phys., 12, 5827–5839,
S. Dhomse, M. P. Chipperfield, W. Feng, and J. D. Haigh
Atmos. Chem. Phys., 11, 12773–12786,
A. J. G. Baumgaertner, A. Seppälä, P. Jöckel, and M. A. Clilverd
Atmos. Chem. Phys., 11, 4521–4531,
J. Flemming, A. Inness, L. Jones, H. J. Eskes, V. Huijnen, M. G. Schultz, O. Stein, D. Cariolle, D. Kinnison, and G. Brasseur
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