Articles | Volume 10, issue 5
© Author(s) 2010. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
© Author(s) 2010. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Validation of Ozone Monitoring Instrument (OMI) ozone profiles and stratospheric ozone columns with Microwave Limb Sounder (MLS) measurements
Goddard Earth Sciences and Technology Center, University of Maryland, Baltimore County, Baltimore, Maryland, USA
Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, USA
NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
P. K. Bhartia
NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, USA
NASA Jet Propulsion Laboratory, Pasadena, California, USA
R. J. D. Spurr
RT Solutions Inc., Cambridge, Massachusetts, USA
T. P. Kurosu
Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, USA
Related subject area
Subject: Gases | Research Activity: Remote Sensing | Altitude Range: Stratosphere | Science Focus: Chemistry (chemical composition and reactions)Observed changes in stratospheric circulation: decreasing lifetime of N2O, 2005–2021Water vapour and ozone in the upper troposphere–lower stratosphere: global climatologies from three Canadian limb-viewing instrumentsUpdated trends of the stratospheric ozone vertical distribution in the 60° S–60° N latitude range based on the LOTUS regression modelPolar stratospheric nitric acid depletion surveyed from a decadal dataset of IASI total columnsGlobal total ozone recovery trends attributed to ozone-depleting substance (ODS) changes derived from five merged ozone datasetsGlobal, regional and seasonal analysis of total ozone trends derived from the 1995–2020 GTO-ECV climate data recordUpper stratospheric ClO and HOCl trends (2005–2020): Aura Microwave Limb Sounder and model resultsChallenge of modelling GLORIA observations of upper troposphere–lowermost stratosphere trace gas and cloud distributions at high latitudes: a case study with state-of-the-art modelsA single-peak-structured solar cycle signal in stratospheric ozone based on Microwave Limb Sounder observations and model simulationsOClO as observed by TROPOMI: a comparison with meteorological parameters and polar stratospheric cloud observationsThe Michelson Interferometer for Passive Atmospheric Sounding global climatology of BrONO2 2002–2012: a test for stratospheric bromine chemistryMicrowave Limb Sounder (MLS) observations of biomass burning products in the stratosphere from Canadian forest fires in August 2017Exceptional loss in ozone in the Arctic winter/spring of 2019/2020Fifty years of balloon-borne ozone profile measurements at Uccle, Belgium: a short history, the scientific relevance, and the achievements in understanding the vertical ozone distributionOn the use of satellite observations to fill gaps in the Halley station total ozone recordPollution trace gases C2H6, C2H2, HCOOH, and PAN in the North Atlantic UTLS: observations and simulationsMeasurement report: regional trends of stratospheric ozone evaluated using the MErged GRIdded Dataset of Ozone Profiles (MEGRIDOP)Indicators of Antarctic ozone depletion: 1979 to 2019Observational evidence of energetic particle precipitation NOx (EPP-NOx) interaction with chlorine curbing Antarctic ozone lossTotal column ozone in New Zealand and in the UK in the 1950sStudy of the dependence of long-term stratospheric ozone trends on local solar timeTechnical note: LIMS observations of lower stratospheric ozone in the southern polar springtime of 1978Chlorine partitioning near the polar vortex edge observed with ground-based FTIR and satellites at Syowa Station, Antarctica, in 2007 and 2011Is the recovery of stratospheric O3 speeding up in the Southern Hemisphere? An evaluation from the first IASI decadal record (2008–2017)Nitrification of the lowermost stratosphere during the exceptionally cold Arctic winter 2015–2016Improved FTIR retrieval strategy for HCFC-22 (CHClF2), comparisons with in situ and satellite datasets with the support of models, and determination of its long-term trend above JungfraujochA study on harmonizing total ozone assimilation with multiple sensorsUnusual chlorine partitioning in the 2015/16 Arctic winter lowermost stratosphere: observations and simulationsDynamically controlled ozone decline in the tropical mid-stratosphere observed by SCIAMACHYStratospheric ozone loss in the Arctic winters between 2005 and 2013 derived with ACE-FTS measurementsSpace–time variability in UTLS chemical distribution in the Asian summer monsoon viewed by limb and nadir satellite sensorsUsing satellite measurements of N2O to remove dynamical variability from HCl measurementsMiddle atmospheric ozone, nitrogen dioxide and nitrogen trioxide in 2002–2011: SD-WACCM simulations compared to GOMOS observationsThe Network for the Detection of Atmospheric Composition Change (NDACC): history, status and perspectivesSpatio-temporal variations of nitric acid total columns from 9 years of IASI measurements – a driver studyDiurnal variation in middle-atmospheric ozone observed by ground-based microwave radiometry at Ny-Ålesund over 1 yearTotal ozone trends from 1979 to 2016 derived from five merged observational datasets – the emergence into ozone recoveryThe impact of nonuniform sampling on stratospheric ozone trends derived from occultation instrumentsDiurnal variations of BrONO2 observed by MIPAS-B at midlatitudes and in the ArcticMerged SAGE II, Ozone_cci and OMPS ozone profile dataset and evaluation of ozone trends in the stratosphereReconciling differences in stratospheric ozone compositesAn update on ozone profile trends for the period 2000 to 2016Effect of volcanic aerosol on stratospheric NO2 and N2O5 from 2002–2014 as measured by Odin-OSIRIS and Envisat-MIPASResponse of trace gases to the disrupted 2015–2016 quasi-biennial oscillationExtending methane profiles from aircraft into the stratosphere for satellite total column validation using the ECMWF C-IFS and TOMCAT/SLIMCAT 3-D modelAn Atlantic streamer in stratospheric ozone observations and SD-WACCM simulation dataTwo mechanisms of stratospheric ozone loss in the Northern Hemisphere, studied using data assimilation of Odin/SMR atmospheric observationsProbing the subtropical lowermost stratosphere and the tropical upper troposphere and tropopause layer for inorganic bromineCase studies of the impact of orbital sampling on stratospheric trend detection and derivation of tropical vertical velocities: solar occultation vs. limb emission soundingSatellite observations of stratospheric hydrogen fluoride and comparisons with SLIMCAT calculations
Michael J. Prather, Lucien Froidevaux, and Nathaniel J. Livesey
Atmos. Chem. Phys., 23, 843–849,Short summary
From satellite data for nitrous oxide (N2O), ozone and temperature, we calculate the monthly loss of N2O and find it is increasing faster than expected, resulting in a shorter lifetime, which reduces the impact of anthropogenic emissions. We identify the cause as enhanced vertical lofting of high-N2O air into the tropical middle stratosphere, where it is destroyed photochemically. Because global warming is due in part to N2O, this finding presents a new negative climate-chemistry feedback.
Paul S. Jeffery, Kaley A. Walker, Chris E. Sioris, Chris D. Boone, Doug Degenstein, Gloria L. Manney, C. Thomas McElroy, Luis Millán, David A. Plummer, Niall J. Ryan, Patrick E. Sheese, and Jiansheng Zou
Atmos. Chem. Phys., 22, 14709–14734,Short summary
The upper troposphere–lower stratosphere is one of the most variable regions in the atmosphere. To improve our understanding of water vapour and ozone concentrations in this region, climatologies have been developed from 14 years of measurements from three Canadian satellite instruments. Horizontal and vertical coordinates have been chosen to minimize the effects of variability. To aid in analysis, model simulations have been used to characterize differences between instrument climatologies.
Sophie Godin-Beekmann, Niramson Azouz, Viktoria F. Sofieva, Daan Hubert, Irina Petropavlovskikh, Peter Effertz, Gérard Ancellet, Doug A. Degenstein, Daniel Zawada, Lucien Froidevaux, Stacey Frith, Jeannette Wild, Sean Davis, Wolfgang Steinbrecht, Thierry Leblanc, Richard Querel, Kleareti Tourpali, Robert Damadeo, Eliane Maillard Barras, René Stübi, Corinne Vigouroux, Carlo Arosio, Gerald Nedoluha, Ian Boyd, Roeland Van Malderen, Emmanuel Mahieu, Dan Smale, and Ralf Sussmann
Atmos. Chem. Phys., 22, 11657–11673,Short summary
An updated evaluation up to 2020 of stratospheric ozone profile long-term trends at extrapolar latitudes based on satellite and ground-based records is presented. Ozone increase in the upper stratosphere is confirmed, with significant trends at most latitudes. In this altitude region, a very good agreement is found with trends derived from chemistry–climate model simulations. Observed and modelled trends diverge in the lower stratosphere, but the differences are non-significant.
Catherine Wespes, Gaetane Ronsmans, Lieven Clarisse, Susan Solomon, Daniel Hurtmans, Cathy Clerbaux, and Pierre-François Coheur
Atmos. Chem. Phys., 22, 10993–11007,Short summary
The first 10-year data record (2008–2017) of HNO3 total columns measured by the IASI-A/MetOp infrared sounder is exploited to monitor the relationship between the temperature decrease and the HNO3 loss observed each year in the Antarctic stratosphere during the polar night. We verify the recurrence of specific regimes in the cycle of IASI HNO3 and identify the day and the 50 hPa temperature (
drop temperature) corresponding to the onset of denitrification in Antarctic winter for each year.
Mark Weber, Carlo Arosio, Melanie Coldewey-Egbers, Vitali E. Fioletov, Stacey M. Frith, Jeannette D. Wild, Kleareti Tourpali, John P. Burrows, and Diego Loyola
Atmos. Chem. Phys., 22, 6843–6859,Short summary
Long-term trends in column ozone have been determined from five merged total ozone datasets spanning the period 1978–2020. We show that ozone recovery due to the decline in stratospheric halogens after the 1990s (as regulated by the Montreal Protocol) is evident outside the tropical region and amounts to half a percent per decade. The ozone recovery in the Northern Hemisphere is however compensated for by the negative long-term trend contribution from atmospheric dynamics since the year 2000.
Melanie Coldewey-Egbers, Diego G. Loyola, Christophe Lerot, and Michel Van Roozendael
Atmos. Chem. Phys., 22, 6861–6878,Short summary
Monitoring the long-term evolution of ozone and the evaluation of trends is essential to assess the efficacy of the Montreal Protocol and its amendments. The first signs of recovery as a consequence of decreasing amounts of ozone-depleting substances have been reported, but the impact needs to be investigated in more detail. In the Southern Hemisphere significant positive trends were found, but in the Northern Hemisphere the expected increase is still not yet visible.
Lucien Froidevaux, Douglas E. Kinnison, Michelle L. Santee, Luis F. Millán, Nathaniel J. Livesey, William G. Read, Charles G. Bardeen, John J. Orlando, and Ryan A. Fuller
Atmos. Chem. Phys., 22, 4779–4799,Short summary
We analyze satellite-derived distributions of chlorine monoxide (ClO) and hypochlorous acid (HOCl) in the upper atmosphere. For 2005–2020, from 50°S to 50°N and over ~30 to 45 km, ClO and HOCl decreased by −0.7 % and −0.4 % per year, respectively. A detailed model of chemistry and dynamics agrees with the results. These decreases confirm the effectiveness of the 1987 Montreal Protocol, which limited emissions of chlorine- and bromine-containing source gases, in order to protect the ozone layer.
Florian Haenel, Wolfgang Woiwode, Jennifer Buchmüller, Felix Friedl-Vallon, Michael Höpfner, Sören Johansson, Farahnaz Khosrawi, Oliver Kirner, Anne Kleinert, Hermann Oelhaf, Johannes Orphal, Roland Ruhnke, Björn-Martin Sinnhuber, Jörn Ungermann, Michael Weimer, and Peter Braesicke
Atmos. Chem. Phys., 22, 2843–2870,Short summary
We compare remote sensing observations of H2O, O3, HNO3 and clouds in the upper troposphere–lowermost stratosphere during an Arctic winter long-range research flight with simulations by two different state-of-the-art model systems. We find good agreement for dynamical structures, trace gas distributions and clouds. We investigate model biases and sensitivities, with the goal of aiding model development and improving our understanding of processes in the upper troposphere–lowermost stratosphere.
Sandip S. Dhomse, Martyn P. Chipperfield, Wuhu Feng, Ryan Hossaini, Graham W. Mann, Michelle L. Santee, and Mark Weber
Atmos. Chem. Phys., 22, 903–916,Short summary
Solar flux variations associated with 11-year sunspot cycle is believed to exert important external climate forcing. As largest variations occur at shorter wavelengths such as ultra-violet part of the solar spectrum, associated changes in stratospheric ozone are thought to provide direct evidence for solar climate interaction. Until now, most of the studies reported double-peak structured solar cycle signal (SCS), but relatively new satellite data suggest only single-peak-structured SCS.
Jānis Puķīte, Christian Borger, Steffen Dörner, Myojeong Gu, and Thomas Wagner
Atmos. Chem. Phys., 22, 245–272,Short summary
Chlorine dioxide (OClO) is an indicator for chlorine activation. New OClO data by TROPOMI (S5P) are interpreted in a meteorological context and related to CALIOP PSC observations. We report very high OClO levels for the northern hemispheric winter 2019/20 with an extraordinarily long period with a stable polar vortex. A minor stratospheric warming in the Southern Hemisphere was also observed in September 2019, where usual OClO values rapidly deactivated 1–2 weeks earlier.
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,Short summary
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.
Hugh C. Pumphrey, Michael J. Schwartz, Michelle L. Santee, George P. Kablick III, Michael D. Fromm, and Nathaniel J. Livesey
Atmos. Chem. Phys., 21, 16645–16659,Short summary
Forest fires in British Columbia in August 2017 caused an unusual phenomonon: smoke and gases from the fires rose quickly to a height of 10 km. From there, the pollution continued to rise more slowly for many weeks, travelling around the world as it did so. In this paper, we describe how we used data from a satellite instrument to observe this polluted volume of air. The satellite has now been working for 16 years but has observed only three events of this type.
Jayanarayanan Kuttippurath, Wuhu Feng, Rolf Müller, Pankaj Kumar, Sarath Raj, Gopalakrishna Pillai Gopikrishnan, and Raina Roy
Atmos. Chem. Phys., 21, 14019–14037,Short summary
The Arctic winter/spring 2020 was one of the coldest with a strong and long-lasting vortex, high chlorine activation, severe denitrification, and unprecedented ozone loss. The loss was even equal to the levels of some of the warm Antarctic winters. Total column ozone values below 220 DU for several weeks and ozone loss saturation were observed during the period. These results show an unusual meteorology and warrant dedicated studies on the impact of climate change on ozone loss.
Roeland Van Malderen, Dirk De Muer, Hugo De Backer, Deniz Poyraz, Willem W. Verstraeten, Veerle De Bock, Andy W. Delcloo, Alexander Mangold, Quentin Laffineur, Marc Allaart, Frans Fierens, and Valérie Thouret
Atmos. Chem. Phys., 21, 12385–12411,Short summary
The main aim of initiating measurements of the vertical distribution of the ozone concentration by means of ozonesondes attached to weather balloons at Uccle in 1969 was to improve weather forecasts. Since then, this measurement technique has barely changed, but the dense, long-term, and homogeneous Uccle dataset currently remains crucial for studying the temporal evolution of ozone from the surface to the stratosphere and is also the backbone of the validation of satellite ozone retrievals.
Lily N. Zhang, Susan Solomon, Kane A. Stone, Jonathan D. Shanklin, Joshua D. Eveson, Steve Colwell, John P. Burrows, Mark Weber, Pieternel F. Levelt, Natalya A. Kramarova, and David P. Haffner
Atmos. Chem. Phys., 21, 9829–9838,Short summary
In the 1980s, measurements at the British Antarctic Survey station in Halley, Antarctica, led to the discovery of the ozone hole. The Halley total ozone record continues to be uniquely valuable for studies of long-term changes in Antarctic ozone. Environmental conditions in 2017 forced a temporary cessation of operations, leading to a gap in the historic record. We develop and test a method for filling in the Halley record using satellite data and find evidence to further support ozone recovery.
Gerald Wetzel, Felix Friedl-Vallon, Norbert Glatthor, Jens-Uwe Grooß, Thomas Gulde, Michael Höpfner, Sören Johansson, Farahnaz Khosrawi, Oliver Kirner, Anne Kleinert, Erik Kretschmer, Guido Maucher, Hans Nordmeyer, Hermann Oelhaf, Johannes Orphal, Christof Piesch, Björn-Martin Sinnhuber, Jörn Ungermann, and Bärbel Vogel
Atmos. Chem. Phys., 21, 8213–8232,Short summary
Measurements of the pollutants C2H6, C2H2, HCOOH, and PAN were performed in the North Atlantic UTLS region with the airborne limb imager GLORIA in 2017. Enhanced amounts of these species were detected in the upper troposphere and even in the lowermost stratosphere (PAN). Main sources of these gases are forest fires in North America and anthropogenic pollution in South Asia. Simulations of EMAC and CAMS are qualitatively able to reproduce the measured data but underestimate the absolute amounts.
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,Short summary
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.
Greg E. Bodeker and Stefanie Kremser
Atmos. Chem. Phys., 21, 5289–5300,Short summary
This paper presents measures of the severity of the Antarctic ozone hole covering the period 1979 to 2019. The paper shows that while the severity of Antarctic ozone depletion grew rapidly through the last two decades of the 20th century, the severity declined thereafter and faster than expected from declines in stratospheric concentrations of the chlorine- and bromine-containing chemical compounds that destroy ozone.
Emily M. Gordon, Annika Seppälä, Bernd Funke, Johanna Tamminen, and Kaley A. Walker
Atmos. Chem. Phys., 21, 2819–2836,Short summary
Energetic particle precipitation (EPP) is the rain of solar energetic particles into the Earth's atmosphere. EPP is known to deplete O3 in the polar mesosphere–upper stratosphere via the formation of NOx. NOx also causes chlorine deactivation in the lower stratosphere and has, thus, been proposed to potentially result in reduced ozone depletion in the spring. We provide the first evidence to show that NOx formed by EPP is able to remove active chlorine, resulting in enhanced total ozone column.
Stefan Brönnimann and Sylvia Nichol
Atmos. Chem. Phys., 20, 14333–14346,Short summary
Historical column ozone data from New Zealand and the UK from the 1950s are digitised and re-evaluated. They allow studying the ozone layer prior to the era of ozone depletion. Day-to-day changes are addressed, which reflect the flow near the tropopause and hence may serve as a diagnostic for atmospheric circulation in a time and region of sparse radiosondes. A long-term comparison shows the amount of ozone depletion at southern mid-latitudes and indicates how far we are from full recovery.
Eliane Maillard Barras, Alexander Haefele, Liliane Nguyen, Fiona Tummon, William T. Ball, Eugene V. Rozanov, Rolf Rüfenacht, Klemens Hocke, Leonie Bernet, Niklaus Kämpfer, Gerald Nedoluha, and Ian Boyd
Atmos. Chem. Phys., 20, 8453–8471,Short summary
To determine the part of the variability of the long-term ozone profile trends coming from measurement timing, we estimate microwave radiometer trends for each hour of the day with a multiple linear regression model. The variation in the trend with local solar time is not significant at the 95 % confidence level either in the stratosphere or in the low mesosphere. We conclude that systematic sampling differences between instruments cannot explain significant differences in trend estimates.
Ellis Remsberg, V. Lynn Harvey, Arlin Krueger, Larry Gordley, John C. Gille, and James M. Russell III
Atmos. Chem. Phys., 20, 3663–3668,Short summary
The Nimbus 7 limb infrared monitor of the stratosphere (LIMS) instrument operated from October 25, 1978, through May 28, 1979. This note focuses on the lower stratosphere of the southern hemisphere, subpolar regions in relation to the position of the polar vortex. Both LIMS ozone and nitric acid show reductions within the edge of the polar vortex at 46 hPa near 60° S from late October through mid-November 1978, indicating that there was a chemical loss of Antarctic ozone some weeks earlier.
Hideaki Nakajima, Isao Murata, Yoshihiro Nagahama, Hideharu Akiyoshi, Kosuke Saeki, Takeshi Kinase, Masanori Takeda, Yoshihiro Tomikawa, Eric Dupuy, and Nicholas B. Jones
Atmos. Chem. Phys., 20, 1043–1074,Short summary
This paper presents temporal evolution of stratospheric chlorine and minor species related to Antarctic ozone depletion, based on FTIR measurements at Syowa Station, and satellite measurements by MLS and MIPAS in 2007 and 2011. After chlorine reservoir species were processed on PSCs and active ClO was formed, different chlorine deactivation pathways into reservoir species were identified, depending on the relative location of Syowa Station to the polar vortex boundary.
Catherine Wespes, Daniel Hurtmans, Simon Chabrillat, Gaétane Ronsmans, Cathy Clerbaux, and Pierre-François Coheur
Atmos. Chem. Phys., 19, 14031–14056,Short summary
This paper highlights the global fingerprint of recent changes in O3 in both the middle–upper and lower stratosphere from the first 10 years of the IASI/Metop-A satellite measurements. The results present the first detection of a significant O3 recovery at middle–high latitudes in winter–spring in the stratosphere as well as in the total column from one single dataset. They also show a speeding up in the recovery at high southern latitudes contrasting with a decline at northern mid-latitudes.
Marleen Braun, Jens-Uwe Grooß, Wolfgang Woiwode, Sören Johansson, Michael Höpfner, Felix Friedl-Vallon, Hermann Oelhaf, Peter Preusse, Jörn Ungermann, Björn-Martin Sinnhuber, Helmut Ziereis, and Peter Braesicke
Atmos. Chem. Phys., 19, 13681–13699,Short summary
We analyse nitrification of the LMS in the Arctic winter 2015–2016 based on GLORIA measurements. Vertical cross sections of HNO3 for several flights show complex fine–scale structures and enhanced values down to 9 km. The extent of overall nitrification is quantified based on HNO3–O3 correlations and reaches between 5 ppbv and 7 ppbv at potential temperature levels between 350 and 380 K. Further, we compare our result with the atmospheric model CLaMS.
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,Short summary
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.
Yves J. Rochon, Michael Sitwell, and Young-Min Cho
Atmos. Chem. Phys., 19, 9431–9451,Short summary
This paper describes adaptable methodologies and results of bias correction applied for the assimilation of total column ozone data from different satellite instruments. The results demonstrate the capability of ensuring short-term forecast biases of total column ozone to be typically within 1 % of a reference for latitudinal ranges where measurements are available. The bias estimation and correction software can be utilized for measurements of other constituents.
Sören Johansson, Michelle L. Santee, Jens-Uwe Grooß, Michael Höpfner, Marleen Braun, Felix Friedl-Vallon, Farahnaz Khosrawi, Oliver Kirner, Erik Kretschmer, Hermann Oelhaf, Johannes Orphal, Björn-Martin Sinnhuber, Ines Tritscher, Jörn Ungermann, Kaley A. Walker, and Wolfgang Woiwode
Atmos. Chem. Phys., 19, 8311–8338,Short summary
We present a study based on GLORIA aircraft and MLS/ACE-FTS/CALIOP satellite measurements during the Arctic winter 2015/16, which demonstrate (for the Arctic) unusual chlorine deactivation into HCl instead of ClONO2 due to low ozone abundances in the lowermost stratosphere, with a focus at 380 K potential temperature. The atmospheric models CLaMS and EMAC are evaluated, and measured ClONO2 is linked with transport and in situ deactivation in the lowermost stratosphere.
Evgenia Galytska, Alexey Rozanov, Martyn P. Chipperfield, Sandip. S. Dhomse, Mark Weber, Carlo Arosio, Wuhu Feng, and John P. Burrows
Atmos. Chem. Phys., 19, 767–783,Short summary
In this study we analysed ozone changes in the tropical mid-stratosphere as observed by the SCIAMACHY instrument during 2004–2012. We used simulations from TOMCAT model with different chemical and dynamical forcings to reveal primary causes of ozone changes. We also considered measured NO2 and modelled NOx, NOx, and N2O data. With modelled AoA data we identified seasonal changes in the upwelling speed and explained how those changes affect N2O chemistry which leads to observed ozone changes.
Debora Griffin, Kaley A. Walker, Ingo Wohltmann, Sandip S. Dhomse, Markus Rex, Martyn P. Chipperfield, Wuhu Feng, Gloria L. Manney, Jane Liu, and David Tarasick
Atmos. Chem. Phys., 19, 577–601,Short summary
Ozone in the stratosphere is important to protect the Earth from UV radiation. Using measurements taken by the Atmospheric Chemistry Experiment satellite between 2005 and 2013, we examine different methods to calculate the ozone loss in the high Arctic and establish the altitude at which most of the ozone is destroyed. Our results show that the different methods agree within the uncertainties. Recommendations are made on which methods are most appropriate to use.
Jiali Luo, Laura L. Pan, Shawn B. Honomichl, John W. Bergman, William J. Randel, Gene Francis, Cathy Clerbaux, Maya George, Xiong Liu, and Wenshou Tian
Atmos. Chem. Phys., 18, 12511–12530,Short summary
We analyze upper tropospheric CO and O3 using satellite data from limb-viewing (MLS) and nadir-viewing (IASI and OMI) sensors, together with dynamical variables, to examine how the two types of data complement each other in representing the chemical variability associated with the day-to-day dynamical variability in the Asian summer monsoon anticyclone. The results provide new observational evidence of eddy shedding in upper tropospheric CO distribution.
Richard S. Stolarski, Anne R. Douglass, and Susan E. Strahan
Atmos. Chem. Phys., 18, 5691–5697,Short summary
Detecting trends in short data sets of stratospheric molecules is difficult because of variability due to dynamical fluctuations. We suggest that one way around this difficulty is using the measurements of one molecule to remove dynamical variability from the measurements of another molecule. We illustrate this using Aura MLS measurements of N2O to help us sort out issues in the determination of trends in HCl. This shows that HCl is decreasing throughout the middle stratosphere as expected.
Erkki Kyrölä, Monika E. Andersson, Pekka T. Verronen, Marko Laine, Simo Tukiainen, and Daniel R. Marsh
Atmos. Chem. Phys., 18, 5001–5019,Short summary
In this work we compare three key constituents of the middle atmosphere (ozone, NO2, and NO3) from the GOMOS satellite instrument with the WACCM model. We find that in the stratosphere (below 50 km) ozone differences are very small, but in the mesosphere large deviations are found. GOMOS and WACCM NO2 agree reasonably well except in the polar areas. These differences can be connected to the solar particle storms. For NO3, WACCM results agree with GOMOS with a very high correlation.
Martine De Mazière, Anne M. Thompson, Michael J. Kurylo, Jeannette D. Wild, Germar Bernhard, Thomas Blumenstock, Geir O. Braathen, James W. Hannigan, Jean-Christopher Lambert, Thierry Leblanc, Thomas J. McGee, Gerald Nedoluha, Irina Petropavlovskikh, Gunther Seckmeyer, Paul C. Simon, Wolfgang Steinbrecht, and Susan E. Strahan
Atmos. Chem. Phys., 18, 4935–4964,Short summary
This paper serves as an introduction to the special issue "Twenty-five years of operations of the Network for the Detection of Atmospheric Composition Change (NDACC)". It describes the origins of the network, its actual status, and some perspectives for its future evolution in the context of atmospheric sciences.
Gaétane Ronsmans, Catherine Wespes, Daniel Hurtmans, Cathy Clerbaux, and Pierre-François Coheur
Atmos. Chem. Phys., 18, 4403–4423,Short summary
The paper aims at understanding the variability of nitric acid (HNO3) in the stratosphere; 9-year time series of IASI measurements are analysed and, for the first time for HNO3, fitted with regression models in order to identify the factors at play. It was found that the annual variability is the main driver and that the polar stratospheric clouds influence greatly HNO3 variability at polar latitudes. The results show the potential of such analyses to better understand the polar processes.
Franziska Schranz, Susana Fernandez, Niklaus Kämpfer, and Mathias Palm
Atmos. Chem. Phys., 18, 4113–4130,Short summary
We present 1 year of ozone measurements form two ground-based microwave radiometers located at Ny-Ålesund, Svalbard. The ozone measurements cover an altitude range of 25–70 km altitude and have a high time resolution of 1–2 h. With these datasets and model data a comprehensive analysis of the ozone diurnal cycle in the Arctic is performed for the different insolation conditions throughout the year. In the stratosphere we find a diurnal cycle which persists over the whole polar day.
Mark Weber, Melanie Coldewey-Egbers, Vitali E. Fioletov, Stacey M. Frith, Jeannette D. Wild, John P. Burrows, Craig S. Long, and Diego Loyola
Atmos. Chem. Phys., 18, 2097–2117,Short summary
This paper commemorates the 30-year anniversary of the initial signing of the Montreal Protocol (MP) on substances that deplete the ozone layer. The MP is so far successful in reducing ozone-depleting substances, and total ozone decline was successfully stopped by the late 1990s. Total ozone levels have been mostly stable since then. In some regions, barely significant upward trends are observed that suggest an emergence into the expected ozone recovery phase.
Robert P. Damadeo, Joseph M. Zawodny, Ellis E. Remsberg, and Kaley A. Walker
Atmos. Chem. Phys., 18, 535–554,Short summary
An ozone trend analysis that compensates for sampling biases is applied to sparsely sampled occultation data sets. International assessments have noted deficiencies in past trend analyses and this work addresses those sources of uncertainty. The nonuniform sampling patterns in data sets and drifts between data sets can affect derived recovery trends by up to 2 % decade−1. The limitations inherent to all techniques are also described and a potential path forward towards resolution is presented.
Gerald Wetzel, Hermann Oelhaf, Michael Höpfner, Felix Friedl-Vallon, Andreas Ebersoldt, Thomas Gulde, Sebastian Kazarski, Oliver Kirner, Anne Kleinert, Guido Maucher, Hans Nordmeyer, Johannes Orphal, Roland Ruhnke, and Björn-Martin Sinnhuber
Atmos. Chem. Phys., 17, 14631–14643,Short summary
We report the first stratospheric measurements of the diurnal variation in the inorganic bromine (Bry) reservoir species BrONO2 around sunrise and sunset. The main goal of these observations was to check the current understanding of stratospheric bromine chemistry and to estimate the amount of lower-stratospheric Bry. The calculated temporal variation in BrONO2 largely reproduces the balloon-borne observations. The amount of Bry was estimated to be about 21–25 pptv in the lower stratosphere.
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,Short summary
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.
William T. Ball, Justin Alsing, Daniel J. Mortlock, Eugene V. Rozanov, Fiona Tummon, and Joanna D. Haigh
Atmos. Chem. Phys., 17, 12269–12302,Short summary
Several ozone composites show different decadal trends, even in composites built with the same data. We remove artefacts affecting trend analysis with a new method (BASIC) and construct an ozone composite, with uncertainties. We find a significant ozone recovery since 1998 in the midlatitude upper stratosphere, with no hemispheric difference. We recommend using a similar approach to construct a composite based on the original instrument data to improve stratospheric ozone trend estimates.
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,Short summary
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.
Cristen Adams, Adam E. Bourassa, Chris A. McLinden, Chris E. Sioris, Thomas von Clarmann, Bernd Funke, Landon A. Rieger, and Douglas A. Degenstein
Atmos. Chem. Phys., 17, 8063–8080,Short summary
We measured the relationship between volcanic aerosol and trace gases in the stratosphere using the OSIRIS and MIPAS satellite instruments between 2002 and 2014. We found that levels of stratospheric NO2 and N2O5 both decreased significantly in the presence of volcanic aerosol. These decreases were consistent with the modeling results.
Olga V. Tweedy, Natalya A. Kramarova, Susan E. Strahan, Paul A. Newman, Lawrence Coy, William J. Randel, Mijeong Park, Darryn W. Waugh, and Stacey M. Frith
Atmos. Chem. Phys., 17, 6813–6823,Short summary
In this study we examined the impact of unprecedented disruption in the wind pattern (the quasi-biennial oscillation, or QBO) in the tropical stratosphere (16–48 km above the ground) on chemicals very important to the stratospheric climate such as ozone (O3). During the 2016 boreal summer, total O3 is lower in the extratropics than during previous QBO cycles due to lifting forced from the disruption. This decrease in O3 led to the increase in surface UV index by 8.5 % compared to the 36 yr mean.
Shreeya Verma, Julia Marshall, Mark Parrington, Anna Agustí-Panareda, Sebastien Massart, Martyn P. Chipperfield, Christopher Wilson, and Christoph Gerbig
Atmos. Chem. Phys., 17, 6663–6678,Short summary
Aircraft profiles are a useful reference for validation of satellite-based column-averaged dry air mole fraction data. However, these are available only up to about 9–13 km altitude and therefore need to be extended synthetically into the stratosphere using other sources. In this study, we analyse three different data sources that are available for extension of CH4 profiles by comparing the error introduced by each into the total column and provide recommendations regarding the best approach.
Klemens Hocke, Franziska Schranz, Eliane Maillard Barras, Lorena Moreira, and Niklaus Kämpfer
Atmos. Chem. Phys., 17, 3445–3452,Short summary
Observation and simulation show an Atlantic ozone streamer along the edge region of the polar vortex in the northern middle stratosphere during winter. The Atlantic streamer has wind speeds of about 100 m/s and turns equatorward at a vortex erosion region. We compare the fields of stratospheric ozone and water vapour from ground- and space-based microwave radiometry and SD-WACCM simulations for a better understanding of non-linear transport processes in the middle atmosphere.
Kazutoshi Sagi, Kristell Pérot, Donal Murtagh, and Yvan Orsolini
Atmos. Chem. Phys., 17, 1791–1803,Short summary
We assess and quantify the ozone loss driven by NOx, triggered by stratospheric warmings and the halogens-induced ozone loss, using data assimilation results over a decade. To illustrate the difference between halogen-induced loss and NOx-induced loss, we compared a relatively cold and stable winter (2010/2011) with a composite calculation of four winters (2003/2004, 2005/2006, 2008/2009 and 2012/2013) which were all affected by a major mid-winter sudden stratospheric warming event.
Bodo Werner, Jochen Stutz, Max Spolaor, Lisa Scalone, Rasmus Raecke, James Festa, Santo Fedele Colosimo, Ross Cheung, Catalina Tsai, Ryan Hossaini, Martyn P. Chipperfield, Giorgio S. Taverna, Wuhu Feng, James W. Elkins, David W. Fahey, Ru-Shan Gao, Erik J. Hintsa, Troy D. Thornberry, Free Lee Moore, Maria A. Navarro, Elliot Atlas, Bruce C. Daube, Jasna Pittman, Steve Wofsy, and Klaus Pfeilsticker
Atmos. Chem. Phys., 17, 1161–1186,Short summary
The paper reports on inorganic and organic bromine measured in the tropical tropopause layer (TTL) over the eastern Pacific in early 2013. Bryinorg is found to increase from a mean of 2.63 ± 1.04 ppt for θ in the range of 350–360 K to 5.11 ± 1.57 ppt for θ=390 ± 400 K, whereas in the subtropical lower stratosphere, it reaches 7.66 ± 2.95 ppt for θ in the range of 390–400 K. Within the TTL, total bromine is found to range from 20.3 ppt to 22.3 ppt.
Luis F. Millán, Nathaniel J. Livesey, Michelle L. Santee, Jessica L. Neu, Gloria L. Manney, and Ryan A. Fuller
Atmos. Chem. Phys., 16, 11521–11534,Short summary
This paper describes the impact of orbital sampling applied to stratospheric temperature and trace gas fields. Model fields are sampled using real sampling patterns from different satellites. We find that coarse nonuniform sampling patterns may introduce non-negligible errors into the inferred magnitude of temperature and trace gas trends and necessitate considerably longer records for their definitive detection.
Jeremy J. Harrison, Martyn P. Chipperfield, Christopher D. Boone, Sandip S. Dhomse, Peter F. Bernath, Lucien Froidevaux, John Anderson, and James Russell III
Atmos. Chem. Phys., 16, 10501–10519,Short summary
HF, the dominant stratospheric fluorine reservoir, results from the atmospheric degradation of anthropogenic species such as CFCs, HCFCs, and HFCs. All are strong greenhouse gases, and CFCs and HCFCs deplete stratospheric ozone. We report the comparison of HF global distributions and trends measured by the ACE-FTS and HALOE satellite instruments with the output of SLIMCAT, a chemical transport model. The global HF trends reveal a slowing down in the rate of increase of HF since the 1990s.
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