Articles | Volume 26, issue 10
https://doi.org/10.5194/acp-26-7503-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-26-7503-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
29 May 2026
Research article |
| 29 May 2026
| 29 May 2026
Evaluation of ozone trends in the mesosphere/lower thermosphere using a new merged dataset of ozone profiles
Finnish Meteorological Institute, Helsinki, Finland
Viktoria F. Sofieva
Finnish Meteorological Institute, Helsinki, Finland
Edward Malina
ESA/ESRIN, Frascati, Italy
Pekka T. Verronen
Finnish Meteorological Institute, Helsinki, Finland
Sodankylä Geophysical Observatory, University of Oulu, Sodankylä, Finland
Michelle L. Santee
Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
Manuel López-Puertas
Instituto de Astrofísica de Andalucía, CSIC, Granada, Spain
Bernd Funke
Instituto de Astrofísica de Andalucía, CSIC, Granada, Spain
Gabriele Stiller
Karlsruhe Institute of Technology, Karlsruhe, Germany
Alexandra Laeng
Karlsruhe Institute of Technology, Karlsruhe, Germany
Kaley A. Walker
Department of Physics, University of Toronto, Toronto, Canada
Patrick E. Sheese
Department of Physics, University of Toronto, Toronto, Canada
Mark E. Hervig
GATS, Driggs, Idaho, USA
Benjamin T. Marshall
GATS, Hampton, Virginia, USA
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The 2022 Hunga eruption injected unprecedented quantities of water vapor into the stratosphere, alongside modest amounts of aerosol precursors. We assess its impacts on stratospheric ozone layer using a multi-model ensemble of chemistry-climate simulations. The results confirm the eruption's role in modulating SH mid and high latitudes ozone abundances in the short term, and discuss the different chemical and dynamical processes driving those changes as well as the role of natural variability.
Miriam Sinnhuber, Christina Arras, Stefan Bender, Bernd Funke, Hanli Liu, Daniel R. Marsh, Thomas Reddmann, Eugene Rozanov, Timofei Sukhodolov, Monika E. Szelag, and Jan Maik Wissing
Atmos. Chem. Phys., 25, 14719–14734, https://doi.org/10.5194/acp-25-14719-2025, https://doi.org/10.5194/acp-25-14719-2025, 2025
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Nitric oxide in the upper atmosphere varies with solar activity. Observations show that this starts a chain of processes affecting the ozone layer and climate system. This is often underestimated in models. We compare five models which show large differences in simulated NO. Analysis of these discrepancies identify two processes which interact with each other: the balance between atomic and molecular oxygen in the thermosphere, and a poleward - downward transport in the winter thermosphere.
Sergey Khaykin, Slimane Bekki, Sophie Godin-Beekmann, Michael D. Fromm, Philippe Goloub, Qiaoyun Hu, Béatrice Josse, Alexandra Laeng, Mehdi Meziane, David A. Peterson, Sophie Pelletier, and Valérie Thouret
Atmos. Chem. Phys., 25, 14551–14571, https://doi.org/10.5194/acp-25-14551-2025, https://doi.org/10.5194/acp-25-14551-2025, 2025
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In 2023, massive wildfires in Canada injected huge amounts of smoke into the atmosphere. Surprisingly, despite their intensity, the smoke did not rise very high but lingered at flight cruising altitudes, causing widespread pollution. This study shows how two different pathways lifted smoke into the lower stratosphere and reveals new insights into how wildfires affect air quality and climate, challenging what we thought we knew about fire and atmospheric impacts.
Maryam Ramezani Ziarani, Miriam Sinnhuber, Thomas Reddmann, Bernd Funke, Stefan Bender, and Michael Prather
Geosci. Model Dev., 18, 7891–7905, https://doi.org/10.5194/gmd-18-7891-2025, https://doi.org/10.5194/gmd-18-7891-2025, 2025
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Our study aims to present a new method for incorporating top-down solar forcing into stratospheric ozone relying on linearized ozone scheme. The addition of geomagnetic forcing led to significant ozone losses in the polar upper stratosphere of both hemispheres due to the catalytic cycles involving NOy. In addition to the particle precipitation effect, accounting for solar UV variability in the ICON-ART model leads to the changes in ozone in the tropical stratosphere.
Cecilia Tirelli, Simone Ceccherini, Samuele Del Bianco, Bernd Funke, Michael Höpfner, Ugo Cortesi, and Piera Raspollini
Atmos. Meas. Tech., 18, 5619–5636, https://doi.org/10.5194/amt-18-5619-2025, https://doi.org/10.5194/amt-18-5619-2025, 2025
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The Complete Data Fusion is an a posteriori method used to combine remote sensing products from independent observations of the same or proximate air masses. In this study, we extend the algorithm’s applicability to two-dimensional products, testing it with simulated ozone datasets from nadir and limb measurements. Our results show that the exploitation of the tomographic capabilities of future atmospheric sensors maximizes the information extracted from complementary datasets.
Pekka T. Verronen, Akira Mizuno, Yoshizumi Miyoshi, Sandeep Kumar, Taku Nakajima, Shin-Ichiro Oyama, Tomoo Nagahama, Satonori Nozawa, Monika E. Szeląg, Tuomas Häkkilä, Niilo Kalakoski, Antti Kero, Esa Turunen, Satoshi Kasahara, Shoichiro Yokota, Kunihiro Keika, Tomoaki Hori, Takefumi Mitani, Takeshi Takashima, and Iku Shinohara
Ann. Geophys., 43, 561–578, https://doi.org/10.5194/angeo-43-561-2025, https://doi.org/10.5194/angeo-43-561-2025, 2025
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We use NO column density data from the Syowa station in Antarctica from 2012–2017. We compare these ground-based radiometer observations with results from a global atmosphere model to understand the year-to-year and day-to-day variability, shortcomings of current electron forcing, and how geomagnetic storms are driving the variability of NO. Our results demonstrate an underestimation in the magnitude of day-to-day variability in simulations, which calls for improved electron forcing in models.
Carlo Arosio, Viktoria Sofieva, Andrea Orfanoz-Cheuquelaf, Alexei Rozanov, Klaus-Peter Heue, Diego Loyola, Edward Malina, Ryan M. Stauffer, David Tarasick, Roeland Van Malderen, Jerry R. Ziemke, and Mark Weber
Atmos. Meas. Tech., 18, 3247–3265, https://doi.org/10.5194/amt-18-3247-2025, https://doi.org/10.5194/amt-18-3247-2025, 2025
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Tropospheric ozone affects air quality and climate, being a pollutant and a greenhouse gas. We analyze satellite data of tropospheric ozone columns obtained by combining two types of observations: one providing stratospheric and the other total ozone. We compare common climatological features and study the influence of the tropopause (troposphere to stratosphere boundary) on the results. We also examine trends over the last 20 years and compare satellite data with ozonesondes to identify drifts.
Patrick E. Sheese, Kaley A. Walker, Chris D. Boone, and David A. Plummer
Atmos. Chem. Phys., 25, 5199–5213, https://doi.org/10.5194/acp-25-5199-2025, https://doi.org/10.5194/acp-25-5199-2025, 2025
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Observations from Atmospheric Chemistry Experiment–Fourier Transform Spectrometer (ACE-FTS) are used to examine global stratospheric water vapour trends for 2004–2021. The satellite measurements are used to quantify trend contributions arising from changes in tropical tropopause temperatures, general circulation patterns, and methane concentrations. While most of the observed trends can be explained by these changes, there remains an unaccounted-for and increasing source of water vapour in the lower mid-stratosphere at mid-latitudes, which is discussed.
Tuomas Häkkilä, Maxime Grandin, Markus Battarbee, Monika E. Szeląg, Markku Alho, Leo Kotipalo, Niilo Kalakoski, Pekka T. Verronen, and Minna Palmroth
Ann. Geophys., 43, 217–240, https://doi.org/10.5194/angeo-43-217-2025, https://doi.org/10.5194/angeo-43-217-2025, 2025
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We study the atmospheric impact of auroral electron precipitation through the novel combination of both magnetospheric modelling and atmospheric modelling. We first simulate fluxes of auroral electrons and then use these fluxes to model their atmospheric impact. We find an increase of more than 200 % in thermospheric odd nitrogen and a corresponding decrease in stratospheric ozone of around 0.8 %. The produced auroral electron precipitation is realistic and shows potential for future studies.
Laura N. Saunders, Kaley A. Walker, Gabriele P. Stiller, Thomas von Clarmann, Florian Haenel, Hella Garny, Harald Bönisch, Chris D. Boone, Ariana E. Castillo, Andreas Engel, Johannes C. Laube, Marianna Linz, Felix Ploeger, David A. Plummer, Eric A. Ray, and Patrick E. Sheese
Atmos. Chem. Phys., 25, 4185–4209, https://doi.org/10.5194/acp-25-4185-2025, https://doi.org/10.5194/acp-25-4185-2025, 2025
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We present a 17-year stratospheric age-of-air dataset derived from ACE-FTS satellite measurements of sulfur hexafluoride. This is the longest continuous, global, and vertically resolved age of air time series available to date. In this paper, we show that this dataset agrees well with age-of-air datasets based on measurements from other instruments. We also present trends in the midlatitude lower stratosphere that indicate changes in the global circulation that are predicted by climate models.
Florian Voet, Felix Ploeger, Johannes Laube, Peter Preusse, Paul Konopka, Jens-Uwe Grooß, Jörn Ungermann, Björn-Martin Sinnhuber, Michael Höpfner, Bernd Funke, Gerald Wetzel, Sören Johansson, Gabriele Stiller, Eric Ray, and Michaela I. Hegglin
Atmos. Chem. Phys., 25, 3541–3565, https://doi.org/10.5194/acp-25-3541-2025, https://doi.org/10.5194/acp-25-3541-2025, 2025
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This study refines estimates of the stratospheric “age of air”, a measure of how long air circulates in the stratosphere. By analyzing correlations between trace gases measurable by satellites, the research introduces a method that reduces uncertainties and detects small-scale atmospheric features. This improved understanding of stratospheric circulation is crucial for better climate models and predictions, enhancing our ability to assess the impacts of climate change on the atmosphere.
Louis Rivoire, Marianna Linz, Jessica L. Neu, Pu Lin, and Michelle L. Santee
Atmos. Chem. Phys., 25, 2269–2289, https://doi.org/10.5194/acp-25-2269-2025, https://doi.org/10.5194/acp-25-2269-2025, 2025
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The recovery of the ozone hole since the 1987 Montreal Protocol has been observed in some regions but has yet to be seen globally. We ask how long it will take to witness a global recovery. Using a technique akin to flying a virtual satellite in a climate model, we find that the degree of confidence we place in the answer to this question is dramatically affected by errors in satellite observations.
Paul S. Jeffery, James R. Drummond, C. Thomas McElroy, Kaley A. Walker, and Jiansheng Zou
Atmos. Meas. Tech., 18, 569–602, https://doi.org/10.5194/amt-18-569-2025, https://doi.org/10.5194/amt-18-569-2025, 2025
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The MAESTRO instrument has been monitoring ozone and NO2 since February 2004. A new version of these data products has recently been released; however, these new products must be validated against other datasets to ensure their validity. This study presents such an assessment, using measurements from 11 satellite instruments to characterize the new MAESTRO products. In the stratosphere, good agreement is found for ozone and acceptable agreement is found for NO2 with these other datasets.
Kimberlee Dubé, Susann Tegtmeier, Felix Ploeger, and Kaley A. Walker
Atmos. Chem. Phys., 25, 1433–1447, https://doi.org/10.5194/acp-25-1433-2025, https://doi.org/10.5194/acp-25-1433-2025, 2025
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The transport rate of air in the stratosphere has changed in response to human emissions of greenhouse gases and ozone-depleting substances. This transport rate can be approximated using measurements of long-lived trace gases. We use observations and model results to derive anomalies and trends in the mean rate of stratospheric air transport. We find that air in the Northern Hemisphere aged by up to 0.3 years per decade relative to air in the Southern Hemisphere over 2004–2017.
Norbert Glatthor, Gabriele P. Stiller, Thomas von Clarmann, Bernd Funke, Sylvia Kellmann, and Andrea Linden
Atmos. Chem. Phys., 25, 1175–1208, https://doi.org/10.5194/acp-25-1175-2025, https://doi.org/10.5194/acp-25-1175-2025, 2025
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We present global upper-tropospheric distributions of the pollutants HCN, CO, C2H2, C2H6, PAN, and HCOOH, observed between 2002 and 2012 by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) on the Environmental Satellite (Envisat). By comparing the spatial distributions of their volume mixing ratios and by global correlation and regression analyses, we draw conclusions on their sources, such as biomass burning, anthropogenic sources, and biogenic release.
Jiansheng Zou, Kaley A. Walker, Patrick E. Sheese, Chris D. Boone, Ryan M. Stauffer, Anne M. Thompson, and David W. Tarasick
Atmos. Meas. Tech., 17, 6983–7005, https://doi.org/10.5194/amt-17-6983-2024, https://doi.org/10.5194/amt-17-6983-2024, 2024
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Ozone measurements from the ACE-FTS satellite instrument have been compared to worldwide balloon-borne ozonesonde profiles using pairs of closely spaced profiles and monthly averaged profiles. ACE-FTS typically measures more ozone in the stratosphere by up to 10 %. The long-term stability of the ACE-FTS ozone data is good, exhibiting small (but non-significant) drifts of less than 3 % per decade in the stratosphere. Lower in the profiles, the calculated drifts are larger (up to 10 % per decade).
Viktoria F. Sofieva, Alexei Rozanov, Monika Szelag, John P. Burrows, Christian Retscher, Robert Damadeo, Doug Degenstein, Landon A. Rieger, and Adam Bourassa
Earth Syst. Sci. Data, 16, 5227–5241, https://doi.org/10.5194/essd-16-5227-2024, https://doi.org/10.5194/essd-16-5227-2024, 2024
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Climate-related studies need information about the distribution of stratospheric aerosols, which influence the energy balance of the Earth’s atmosphere. In this work, we present a merged dataset of vertically resolved stratospheric aerosol extinction coefficients, which is derived from data of six limb and occultation satellite instruments. The created aerosol climate record covers the period from October 1984 to December 2023. It can be used in various climate-related studies.
Luis F. Millán, Peter Hoor, Michaela I. Hegglin, Gloria L. Manney, Harald Boenisch, Paul Jeffery, Daniel Kunkel, Irina Petropavlovskikh, Hao Ye, Thierry Leblanc, and Kaley Walker
Atmos. Chem. Phys., 24, 7927–7959, https://doi.org/10.5194/acp-24-7927-2024, https://doi.org/10.5194/acp-24-7927-2024, 2024
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In the Observed Composition Trends And Variability in the UTLS (OCTAV-UTLS) Stratosphere-troposphere Processes And their Role in Climate (SPARC) activity, we have mapped multiplatform ozone datasets into coordinate systems to systematically evaluate the influence of these coordinates on binned climatological variability. This effort unifies the work of studies that focused on individual coordinate system variability. Our goal was to create the most comprehensive assessment of this topic.
Robert P. Damadeo, Viktoria F. Sofieva, Alexei Rozanov, and Larry W. Thomason
Atmos. Meas. Tech., 17, 3669–3678, https://doi.org/10.5194/amt-17-3669-2024, https://doi.org/10.5194/amt-17-3669-2024, 2024
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Comparing different aerosol data sets for scientific studies often requires converting aerosol extinction data between different wavelengths. A common approximation for the spectral behavior of aerosol is the Ångström formula; however, this introduces biases. Using measurements across many different wavelengths from a single instrument, we derive an empirical relationship to both characterize this bias and offer a correction for other studies that may employ this analysis approach.
Karen De Los Ríos, Paulina Ordoñez, Gabriele P. Stiller, Piera Raspollini, Marco Gai, Kaley A. Walker, Cristina Peña-Ortiz, and Luis Acosta
Atmos. Meas. Tech., 17, 3401–3418, https://doi.org/10.5194/amt-17-3401-2024, https://doi.org/10.5194/amt-17-3401-2024, 2024
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This study examines newer versions of H2O and HDO retrievals from Envisat/MIPAS and SCISAT/ACE-FTS. Results reveal a better agreement in stratospheric H2O profiles than in HDO profiles. The H2O tape recorder signal is consistent across databases, but δD tape recorder composites show differences that impact the interpretation of water vapour transport. These findings enhance the need for intercomparisons to refine our insights.
Manuel López-Puertas, Federico Fabiano, Victor Fomichev, Bernd Funke, and Daniel R. Marsh
Geosci. Model Dev., 17, 4401–4432, https://doi.org/10.5194/gmd-17-4401-2024, https://doi.org/10.5194/gmd-17-4401-2024, 2024
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The radiative infrared cooling of CO2 in the middle atmosphere is crucial for computing its thermal structure. It requires one however to include non-local thermodynamic equilibrium processes which are computationally very expensive, which cannot be afforded by climate models. In this work, we present an updated, efficient, accurate and very fast (~50 µs) parameterization of that cooling able to cope with CO2 abundances from half the pre-industrial values to 10 times the current abundance.
Xin Yang, Kimberly Strong, Alison S. Criscitiello, Marta Santos-Garcia, Kristof Bognar, Xiaoyi Zhao, Pierre Fogal, Kaley A. Walker, Sara M. Morris, and Peter Effertz
Atmos. Chem. Phys., 24, 5863–5886, https://doi.org/10.5194/acp-24-5863-2024, https://doi.org/10.5194/acp-24-5863-2024, 2024
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This study uses snow samples collected from a Canadian high Arctic site, Eureka, to demonstrate that surface snow in early spring is a net sink of atmospheric bromine and nitrogen. Surface snow bromide and nitrate are significantly correlated, indicating the oxidation of reactive nitrogen is accelerated by reactive bromine. In addition, we show evidence that snow photochemical release of reactive bromine is very weak, and its emission flux is much smaller than the deposition flux of bromide.
Viktoria F. Sofieva, Monika Szelag, Johanna Tamminen, Didier Fussen, Christine Bingen, Filip Vanhellemont, Nina Mateshvili, Alexei Rozanov, and Christine Pohl
Atmos. Meas. Tech., 17, 3085–3101, https://doi.org/10.5194/amt-17-3085-2024, https://doi.org/10.5194/amt-17-3085-2024, 2024
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We have developed the new multi-wavelength dataset of aerosol extinction profiles, which are retrieved from the averaged transmittance spectra by the Global Ozone Monitoring by Occultation of Stars instrument aboard Envisat. The retrieved aerosol extinction profiles are provided in the altitude range 10–40 km at 400, 440, 452, 470, 500, 525, 550, 672 and 750 nm for the period 2002–2012. FMI-GOMOSaero aerosol profiles have improved quality; they are in good agreement with other datasets.
Norbert Glatthor, Thomas von Clarmann, Bernd Funke, Maya García-Comas, Udo Grabowski, Michael Höpfner, Sylvia Kellmann, Michael Kiefer, Alexandra Laeng, Andrea Linden, Manuel López-Puertas, and Gabriele P. Stiller
Atmos. Meas. Tech., 17, 2849–2871, https://doi.org/10.5194/amt-17-2849-2024, https://doi.org/10.5194/amt-17-2849-2024, 2024
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We present global atmospheric methane (CH4) and nitrous oxide (N2O) distributions retrieved from measurements of the MIPAS instrument on board the Environmental Satellite (Envisat) during 2002 to 2012. Monitoring of these gases is of scientific interest because both of them are strong greenhouse gases. We analyze the latest, improved version of calibrated MIPAS measurements. Further, we apply a new retrieval scheme leading to an improved CH4 and N2O data product .
Felicia Kolonjari, Patrick E. Sheese, Kaley A. Walker, Chris D. Boone, David A. Plummer, Andreas Engel, Stephen A. Montzka, David E. Oram, Tanja Schuck, Gabriele P. Stiller, and Geoffrey C. Toon
Atmos. Meas. Tech., 17, 2429–2449, https://doi.org/10.5194/amt-17-2429-2024, https://doi.org/10.5194/amt-17-2429-2024, 2024
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The Canadian Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE-FTS) satellite instrument is currently providing the only vertically resolved chlorodifluoromethane (HCFC-22) measurements from space. This study assesses the most current ACE-FTS HCFC-22 data product in the upper troposphere and lower stratosphere, as well as modelled HCFC-22 from a 39-year run of the Canadian Middle Atmosphere Model (CMAM39) in the same region.
Paul S. Jeffery, James R. Drummond, Jiansheng Zou, and Kaley A. Walker
Atmos. Chem. Phys., 24, 4253–4263, https://doi.org/10.5194/acp-24-4253-2024, https://doi.org/10.5194/acp-24-4253-2024, 2024
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The MOPITT instrument has been monitoring carbon monoxide (CO) since March 2000. This dataset has been used for many applications; however, episodic emission events, which release large amounts of CO into the atmosphere, are a major source of uncertainty. This study presents a method for identifying these events by determining measurements that are unlikely to have typically arisen. The distribution and frequency of these flagged measurements in the MOPITT dataset are presented and discussed.
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.
Gabriele P. Stiller, Thomas von Clarmann, Norbert Glatthor, Udo Grabowski, Sylvia Kellmann, Michael Kiefer, Alexandra Laeng, Andrea Linden, Bernd Funke, Maya García-Comas, and Manuel López-Puertas
Atmos. Meas. Tech., 17, 1759–1789, https://doi.org/10.5194/amt-17-1759-2024, https://doi.org/10.5194/amt-17-1759-2024, 2024
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CFC-11, CFC-12, and HCFC-22 contribute to the depletion of ozone and are potent greenhouse gases. They have been banned by the Montreal protocol. With MIPAS on Envisat the atmospheric composition could be observed between 2002 and 2012. We present here the retrieval of their atmospheric distributions for the final data version 8. We characterise the derived data by their error budget and their spatial resolution. An additional representation for direct comparison to models is also provided.
Bernd Funke, Thierry Dudok de Wit, Ilaria Ermolli, Margit Haberreiter, Doug Kinnison, Daniel Marsh, Hilde Nesse, Annika Seppälä, Miriam Sinnhuber, and Ilya Usoskin
Geosci. Model Dev., 17, 1217–1227, https://doi.org/10.5194/gmd-17-1217-2024, https://doi.org/10.5194/gmd-17-1217-2024, 2024
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We outline a road map for the preparation of a solar forcing dataset for the upcoming Phase 7 of the Coupled Model Intercomparison Project (CMIP7), considering the latest scientific advances made in the reconstruction of solar forcing and in the understanding of climate response while also addressing the issues that were raised during CMIP6.
Victoria A. Flood, Kimberly Strong, Cynthia H. Whaley, Kaley A. Walker, Thomas Blumenstock, James W. Hannigan, Johan Mellqvist, Justus Notholt, Mathias Palm, Amelie N. Röhling, Stephen Arnold, Stephen Beagley, Rong-You Chien, Jesper Christensen, Makoto Deushi, Srdjan Dobricic, Xinyi Dong, Joshua S. Fu, Michael Gauss, Wanmin Gong, Joakim Langner, Kathy S. Law, Louis Marelle, Tatsuo Onishi, Naga Oshima, David A. Plummer, Luca Pozzoli, Jean-Christophe Raut, Manu A. Thomas, Svetlana Tsyro, and Steven Turnock
Atmos. Chem. Phys., 24, 1079–1118, https://doi.org/10.5194/acp-24-1079-2024, https://doi.org/10.5194/acp-24-1079-2024, 2024
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It is important to understand the composition of the Arctic atmosphere and how it is changing. Atmospheric models provide simulations that can inform policy. This study examines simulations of CH4, CO, and O3 by 11 models. Model performance is assessed by comparing results matched in space and time to measurements from five high-latitude ground-based infrared spectrometers. This work finds that models generally underpredict the concentrations of these gases in the Arctic troposphere.
Andrea Pazmiño, Florence Goutail, Sophie Godin-Beekmann, Alain Hauchecorne, Jean-Pierre Pommereau, Martyn P. Chipperfield, Wuhu Feng, Franck Lefèvre, Audrey Lecouffe, Michel Van Roozendael, Nis Jepsen, Georg Hansen, Rigel Kivi, Kimberly Strong, and Kaley A. Walker
Atmos. Chem. Phys., 23, 15655–15670, https://doi.org/10.5194/acp-23-15655-2023, https://doi.org/10.5194/acp-23-15655-2023, 2023
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The vortex-averaged ozone loss over the last 3 decades is evaluated for both polar regions using the passive ozone tracer of the chemical transport model TOMCAT/SLIMCAT and total ozone observations from the SAOZ network and MSR2 reanalysis. Three metrics were developed to compute ozone trends since 2000. The study confirms the ozone recovery in the Antarctic and shows a potential sign of quantitative detection of ozone recovery in the Arctic that needs to be robustly confirmed in the future.
Manuel López-Puertas, Maya García-Comas, Bernd Funke, Thomas von Clarmann, Norbert Glatthor, Udo Grabowski, Sylvia Kellmann, Michael Kiefer, Alexandra Laeng, Andrea Linden, and Gabriele P. Stiller
Atmos. Meas. Tech., 16, 5609–5645, https://doi.org/10.5194/amt-16-5609-2023, https://doi.org/10.5194/amt-16-5609-2023, 2023
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This paper describes a new version (V8) of ozone data from MIPAS middle-atmosphere spectra. The dataset comprises high-quality ozone profiles from 20 to 100 km, with pole-to-pole latitude coverage for the day- and nighttime, spanning 2005 until 2012. An exhaustive treatment of errors has been performed. Compared to other satellite instruments, MIPAS ozone shows a positive bias of 5 %–8 % below 70 km. In the upper mesosphere, this new version agrees much better than previous ones (within 10 %).
Maya García-Comas, Bernd Funke, Manuel López-Puertas, Norbert Glatthor, Udo Grabowski, Sylvia Kellmann, Michael Kiefer, Andrea Linden, Belén Martínez-Mondéjar, Gabriele P. Stiller, and Thomas von Clarmann
Atmos. Meas. Tech., 16, 5357–5386, https://doi.org/10.5194/amt-16-5357-2023, https://doi.org/10.5194/amt-16-5357-2023, 2023
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We have released version 8 of MIPAS IMK–IAA temperatures and pointing information retrieved from MIPAS Middle and Upper Atmosphere mode version 8.03 calibrated spectra, covering 20–115 km altitude. We considered non-local thermodynamic equilibrium emission explicitly for each limb scan, essential to retrieve accurate temperatures above the mid-mesosphere. Comparisons of this temperature dataset with SABER measurements show excellent agreement, improving those of previous MIPAS versions.
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.
Monali Borthakur, Miriam Sinnhuber, Alexandra Laeng, Thomas Reddmann, Peter Braesicke, Gabriele Stiller, Thomas von Clarmann, Bernd Funke, Ilya Usoskin, Jan Maik Wissing, and Olesya Yakovchuk
Atmos. Chem. Phys., 23, 12985–13013, https://doi.org/10.5194/acp-23-12985-2023, https://doi.org/10.5194/acp-23-12985-2023, 2023
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Reduced ozone levels resulting from ozone depletion mean more exposure to UV radiation, which has various effects on human health. We analysed solar events to see what influence it has on the chemistry of Earth's atmosphere and how this atmospheric chemistry change can affect the ozone. To do this, we used an atmospheric model considering only chemistry and compared it with satellite data. The focus was mainly on the contribution of chlorine, and we found about 10 %–20 % ozone loss due to that.
Michael Kiefer, Dale F. Hurst, Gabriele P. Stiller, Stefan Lossow, Holger Vömel, John Anderson, Faiza Azam, Jean-Loup Bertaux, Laurent Blanot, Klaus Bramstedt, John P. Burrows, Robert Damadeo, Bianca Maria Dinelli, Patrick Eriksson, Maya García-Comas, John C. Gille, Mark Hervig, Yasuko Kasai, Farahnaz Khosrawi, Donal Murtagh, Gerald E. Nedoluha, Stefan Noël, Piera Raspollini, William G. Read, Karen H. Rosenlof, Alexei Rozanov, Christopher E. Sioris, Takafumi Sugita, Thomas von Clarmann, Kaley A. Walker, and Katja Weigel
Atmos. Meas. Tech., 16, 4589–4642, https://doi.org/10.5194/amt-16-4589-2023, https://doi.org/10.5194/amt-16-4589-2023, 2023
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We quantify biases and drifts (and their uncertainties) between the stratospheric water vapor measurement records of 15 satellite-based instruments (SATs, with 31 different retrievals) and balloon-borne frost point hygrometers (FPs) launched at 27 globally distributed stations. These comparisons of measurements during the period 2000–2016 are made using robust, consistent statistical methods. With some exceptions, the biases and drifts determined for most SAT–FP pairs are < 10 % and < 1 % yr−1.
Luis F. Millán, Gloria L. Manney, Harald Boenisch, Michaela I. Hegglin, Peter Hoor, Daniel Kunkel, Thierry Leblanc, Irina Petropavlovskikh, Kaley Walker, Krzysztof Wargan, and Andreas Zahn
Atmos. Meas. Tech., 16, 2957–2988, https://doi.org/10.5194/amt-16-2957-2023, https://doi.org/10.5194/amt-16-2957-2023, 2023
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The determination of atmospheric composition trends in the upper troposphere and lower stratosphere (UTLS) is still highly uncertain. We present the creation of dynamical diagnostics to map several ozone datasets (ozonesondes, lidars, aircraft, and satellite measurements) in geophysically based coordinate systems. The diagnostics can also be used to analyze other greenhouse gases relevant to surface climate and UTLS chemistry.
Frank Werner, Nathaniel J. Livesey, Luis F. Millán, William G. Read, Michael J. Schwartz, Paul A. Wagner, William H. Daffer, Alyn Lambert, Sasha N. Tolstoff, and Michelle L. Santee
Atmos. Meas. Tech., 16, 2733–2751, https://doi.org/10.5194/amt-16-2733-2023, https://doi.org/10.5194/amt-16-2733-2023, 2023
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The algorithm that produces the near-real-time data products of the Aura Microwave Limb Sounder has been updated. The new algorithm is based on machine learning techniques and yields data products with much improved accuracy. It is shown that the new algorithm outperforms the previous versions, even when it is trained on only a few years of satellite observations. This confirms the potential of applying machine learning to the near-real-time efforts of other current and future mission concepts.
Bernd Funke, Maya García-Comas, Norbert Glatthor, Udo Grabowski, Sylvia Kellmann, Michael Kiefer, Andrea Linden, Manuel López-Puertas, Gabriele P. Stiller, and Thomas von Clarmann
Atmos. Meas. Tech., 16, 2167–2196, https://doi.org/10.5194/amt-16-2167-2023, https://doi.org/10.5194/amt-16-2167-2023, 2023
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New global nitric oxide (NO) volume-mixing-ratio and lower-thermospheric temperature data products, retrieved from Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) spectra with the IMK-IAA MIPAS data processor, have been released. The dataset covers the entire Envisat mission lifetime and includes retrieval results from all MIPAS observation modes. The data are based on ESA version 8 calibration and were processed using an improved retrieval approach.
Viktoria F. Sofieva, Monika Szelag, Johanna Tamminen, Carlo Arosio, Alexei Rozanov, Mark Weber, Doug Degenstein, Adam Bourassa, Daniel Zawada, Michael Kiefer, Alexandra Laeng, Kaley A. Walker, Patrick Sheese, Daan Hubert, Michel van Roozendael, Christian Retscher, Robert Damadeo, and Jerry D. Lumpe
Atmos. Meas. Tech., 16, 1881–1899, https://doi.org/10.5194/amt-16-1881-2023, https://doi.org/10.5194/amt-16-1881-2023, 2023
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The paper presents the updated SAGE-CCI-OMPS+ climate data record of monthly zonal mean ozone profiles. This dataset covers the stratosphere and combines measurements by nine limb and occultation satellite instruments (SAGE II, OSIRIS, MIPAS, SCIAMACHY, GOMOS, ACE-FTS, OMPS-LP, POAM III, and SAGE III/ISS). The update includes new versions of MIPAS, ACE-FTS, and OSIRIS datasets and introduces data from additional sensors (POAM III and SAGE III/ISS) and retrieval processors (OMPS-LP).
Michael Kiefer, Thomas von Clarmann, Bernd Funke, Maya García-Comas, Norbert Glatthor, Udo Grabowski, Michael Höpfner, Sylvia Kellmann, Alexandra Laeng, Andrea Linden, Manuel López-Puertas, and Gabriele P. Stiller
Atmos. Meas. Tech., 16, 1443–1460, https://doi.org/10.5194/amt-16-1443-2023, https://doi.org/10.5194/amt-16-1443-2023, 2023
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A new ozone data set, derived from radiation measurements of the space-borne instrument MIPAS, is presented. It consists of more than 2 million single ozone profiles from 2002–2012, covering virtually all latitudes and altitudes between 5 and 70 km. Progress in data calibration and processing methods allowed for significant improvement of the data quality, compared to previous data versions. Hence, the data set will help to better understand e.g. the time evolution of ozone in the stratosphere.
Nasrin Mostafavi Pak, Jacob K. Hedelius, Sébastien Roche, Liz Cunningham, Bianca Baier, Colm Sweeney, Coleen Roehl, Joshua Laughner, Geoffrey Toon, Paul Wennberg, Harrison Parker, Colin Arrowsmith, Joseph Mendonca, Pierre Fogal, Tyler Wizenberg, Beatriz Herrera, Kimberly Strong, Kaley A. Walker, Felix Vogel, and Debra Wunch
Atmos. Meas. Tech., 16, 1239–1261, https://doi.org/10.5194/amt-16-1239-2023, https://doi.org/10.5194/amt-16-1239-2023, 2023
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Ground-based remote sensing instruments in the Total Carbon Column Observing Network (TCCON) measure greenhouse gases in the atmosphere. Consistency between TCCON measurements is crucial to accurately infer changes in atmospheric composition. We use portable remote sensing instruments (EM27/SUN) to evaluate biases between TCCON stations in North America. We also improve the retrievals of EM27/SUN instruments and evaluate the previous (GGG2014) and newest (GGG2020) retrieval algorithms.
Joshua L. Laughner, Sébastien Roche, Matthäus Kiel, Geoffrey C. Toon, Debra Wunch, Bianca C. Baier, Sébastien Biraud, Huilin Chen, Rigel Kivi, Thomas Laemmel, Kathryn McKain, Pierre-Yves Quéhé, Constantina Rousogenous, Britton B. Stephens, Kaley Walker, and Paul O. Wennberg
Atmos. Meas. Tech., 16, 1121–1146, https://doi.org/10.5194/amt-16-1121-2023, https://doi.org/10.5194/amt-16-1121-2023, 2023
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Observations using sunlight to measure surface-to-space total column of greenhouse gases in the atmosphere need an initial guess of the vertical distribution of those gases to start from. We have developed an approach to provide those initial guess profiles that uses readily available meteorological data as input. This lets us make these guesses without simulating them with a global model. The profiles generated this way match independent observations well.
Thomas von Clarmann, Norbert Glatthor, Udo Grabowski, Bernd Funke, Michael Kiefer, Anne Kleinert, Gabriele P. Stiller, Andrea Linden, and Sylvia Kellmann
Atmos. Meas. Tech., 15, 6991–7018, https://doi.org/10.5194/amt-15-6991-2022, https://doi.org/10.5194/amt-15-6991-2022, 2022
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Errors of profiles of temperature and mixing ratios retrieved from spectra recorded with the Michelson Interferometer for Passive Atmospheric Sounding are estimated. All known and quantified sources of uncertainty are considered. Some ongoing uncertaities contribute to both the random and to the systematic errors. In some cases, one source of uncertainty propagates onto the error budget via multiple pathways. Problems arise when the correlations of errors to be propagated are unknown.
Ali Jalali, Kaley A. Walker, Kimberly Strong, Rebecca R. Buchholz, Merritt N. Deeter, Debra Wunch, Sébastien Roche, Tyler Wizenberg, Erik Lutsch, Erin McGee, Helen M. Worden, Pierre Fogal, and James R. Drummond
Atmos. Meas. Tech., 15, 6837–6863, https://doi.org/10.5194/amt-15-6837-2022, https://doi.org/10.5194/amt-15-6837-2022, 2022
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This study validates MOPITT version 8 carbon monoxide measurements over the Canadian high Arctic for the period 2006 to 2019. The MOPITT products from different detector pixels and channels are compared with ground-based measurements from the Polar Environment Atmospheric Research Laboratory (PEARL) in Eureka, Nunavut, Canada. These results show good consistency between the satellite and ground-based measurements and provide guidance on the usage of these MOPITT data at high latitudes.
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, https://doi.org/10.5194/acp-22-14709-2022, https://doi.org/10.5194/acp-22-14709-2022, 2022
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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.
Kimberlee Dubé, Daniel Zawada, Adam Bourassa, Doug Degenstein, William Randel, David Flittner, Patrick Sheese, and Kaley Walker
Atmos. Meas. Tech., 15, 6163–6180, https://doi.org/10.5194/amt-15-6163-2022, https://doi.org/10.5194/amt-15-6163-2022, 2022
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Satellite observations are important for monitoring changes in atmospheric composition. Here we describe an improved version of the NO2 retrieval for the Optical Spectrograph and InfraRed Imager System. The resulting NO2 profiles are compared to those from the Atmospheric Chemistry Experiment – Fourier Transform Spectrometer and the Stratospheric Aerosol and Gas Experiment III on the International Space Station. All datasets agree within 20 % throughout the stratosphere.
Carlo Arosio, Alexei Rozanov, Victor Gorshelev, Alexandra Laeng, and John P. Burrows
Atmos. Meas. Tech., 15, 5949–5967, https://doi.org/10.5194/amt-15-5949-2022, https://doi.org/10.5194/amt-15-5949-2022, 2022
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This paper characterizes the uncertainties affecting the ozone profiles retrieved at the University of Bremen through OMPS limb satellite observations. An accurate knowledge of the uncertainties is relevant for the validation of the product and to correctly interpret the retrieval results. We investigate several sources of uncertainties, estimate a total random and systematic component, and verify the consistency of the combined OMPS-MLS total uncertainty.
Xin Yang, Kimberly Strong, Alison S. Criscitiello, Marta Santos-Garcia, Kristof Bognar, Xiaoyi Zhao, Pierre Fogal, Kaley A. Walker, Sara M. Morris, and Peter Effertz
EGUsphere, https://doi.org/10.5194/egusphere-2022-696, https://doi.org/10.5194/egusphere-2022-696, 2022
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Snow pack in high Arctic plays a key role in polar atmospheric chemistry, especially in spring when photochemistry becomes active. By sampling surface snow from a Canadian high Arctic location at Eureka, Nunavut (80° N, 86° W), we demonstrate that surface snow is a net sink rather than a source of atmospheric reactive bromine and nitrate. This finding is new and opposite to previous conclusions that snowpack is a large and direct source of reactive bromine in polar spring.
Niilo Kalakoski, Viktoria F. Sofieva, René Preusker, Claire Henocq, Matthieu Denisselle, Steffen Dransfeld, and Silvia Scifoni
Atmos. Meas. Tech., 15, 5129–5140, https://doi.org/10.5194/amt-15-5129-2022, https://doi.org/10.5194/amt-15-5129-2022, 2022
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Geophysical validation of the Integrated Water Vapour (IWV) product from the Sentinel-3 Ocean and Land Colour Instrument (OLCI) was performed against reference observations from SUOMINET and IGRA databases. Results for cloud-free matchups over land show a wet bias of 7 %–10 % for OLCI, with a high correlation against the reference observations (0.98 against SUOMINET and 0.90 against IGRA). Special attention is given to validation of uncertainty estimates and cloud flagging.
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, https://doi.org/10.5194/acp-22-11657-2022, https://doi.org/10.5194/acp-22-11657-2022, 2022
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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.
Carsten Baumann, Antti Kero, Shikha Raizada, Markus Rapp, Michael P. Sulzer, Pekka T. Verronen, and Juha Vierinen
Ann. Geophys., 40, 519–530, https://doi.org/10.5194/angeo-40-519-2022, https://doi.org/10.5194/angeo-40-519-2022, 2022
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The Arecibo radar was used to probe free electrons of the ionized atmosphere between 70 and 100 km altitude. This is also the altitude region were meteors evaporate and form secondary particulate matter, the so-called meteor smoke particles (MSPs). Free electrons attach to these MSPs when the sun is below the horizon and cause a drop in the number of free electrons, which are the subject of these measurements. We also identified a different number of free electrons during sunset and sunrise.
William G. Read, Gabriele Stiller, Stefan Lossow, Michael Kiefer, Farahnaz Khosrawi, Dale Hurst, Holger Vömel, Karen Rosenlof, Bianca M. Dinelli, Piera Raspollini, Gerald E. Nedoluha, John C. Gille, Yasuko Kasai, Patrick Eriksson, Christopher E. Sioris, Kaley A. Walker, Katja Weigel, John P. Burrows, and Alexei Rozanov
Atmos. Meas. Tech., 15, 3377–3400, https://doi.org/10.5194/amt-15-3377-2022, https://doi.org/10.5194/amt-15-3377-2022, 2022
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This paper attempts to provide an assessment of the accuracy of 21 satellite-based instruments that remotely measure atmospheric humidity in the upper troposphere of the Earth's atmosphere. The instruments made their measurements from 1984 to the present time; however, most of these instruments began operations after 2000, and only a few are still operational. The objective of this study is to quantify the accuracy of each satellite humidity data set.
Viktoria F. Sofieva, Risto Hänninen, Mikhail Sofiev, Monika Szeląg, Hei Shing Lee, Johanna Tamminen, and Christian Retscher
Atmos. Meas. Tech., 15, 3193–3212, https://doi.org/10.5194/amt-15-3193-2022, https://doi.org/10.5194/amt-15-3193-2022, 2022
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We present tropospheric ozone column datasets that have been created using combinations of total ozone column from OMI and TROPOMI with stratospheric ozone column datasets from several available limb-viewing instruments (MLS, OSIRIS, MIPAS, SCIAMACHY, OMPS-LP, GOMOS). The main results are (i) several methodological developments, (ii) new tropospheric ozone column datasets from OMI and TROPOMI, and (iii) a new high-resolution dataset of ozone profiles from limb satellite instruments.
Irina Mironova, Miriam Sinnhuber, Galina Bazilevskaya, Mark Clilverd, Bernd Funke, Vladimir Makhmutov, Eugene Rozanov, Michelle L. Santee, Timofei Sukhodolov, and Thomas Ulich
Atmos. Chem. Phys., 22, 6703–6716, https://doi.org/10.5194/acp-22-6703-2022, https://doi.org/10.5194/acp-22-6703-2022, 2022
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From balloon measurements, we detected unprecedented, extremely powerful, electron precipitation over the middle latitudes. The robustness of this event is confirmed by satellite observations of electron fluxes and chemical composition, as well as by ground-based observations of the radio signal propagation. The applied chemistry–climate model shows the almost complete destruction of ozone in the mesosphere over the region where high-energy electrons were observed.
Cynthia H. Whaley, Rashed Mahmood, Knut von Salzen, Barbara Winter, Sabine Eckhardt, Stephen Arnold, Stephen Beagley, Silvia Becagli, Rong-You Chien, Jesper Christensen, Sujay Manish Damani, Xinyi Dong, Konstantinos Eleftheriadis, Nikolaos Evangeliou, Gregory Faluvegi, Mark Flanner, Joshua S. Fu, Michael Gauss, Fabio Giardi, Wanmin Gong, Jens Liengaard Hjorth, Lin Huang, Ulas Im, Yugo Kanaya, Srinath Krishnan, Zbigniew Klimont, Thomas Kühn, Joakim Langner, Kathy S. Law, Louis Marelle, Andreas Massling, Dirk Olivié, Tatsuo Onishi, Naga Oshima, Yiran Peng, David A. Plummer, Olga Popovicheva, Luca Pozzoli, Jean-Christophe Raut, Maria Sand, Laura N. Saunders, Julia Schmale, Sangeeta Sharma, Ragnhild Bieltvedt Skeie, Henrik Skov, Fumikazu Taketani, Manu A. Thomas, Rita Traversi, Kostas Tsigaridis, Svetlana Tsyro, Steven Turnock, Vito Vitale, Kaley A. Walker, Minqi Wang, Duncan Watson-Parris, and Tahya Weiss-Gibbons
Atmos. Chem. Phys., 22, 5775–5828, https://doi.org/10.5194/acp-22-5775-2022, https://doi.org/10.5194/acp-22-5775-2022, 2022
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Air pollutants, like ozone and soot, play a role in both global warming and air quality. Atmospheric models are often used to provide information to policy makers about current and future conditions under different emissions scenarios. In order to have confidence in those simulations, in this study we compare simulated air pollution from 18 state-of-the-art atmospheric models to measured air pollution in order to assess how well the models perform.
Alexandra Laeng, Thomas von Clarmann, Quentin Errera, Udo Grabowski, and Shawn Honomichl
Atmos. Meas. Tech., 15, 2407–2416, https://doi.org/10.5194/amt-15-2407-2022, https://doi.org/10.5194/amt-15-2407-2022, 2022
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In validation exercises, a universal excuse used to explain the residual discrepancy between the data is the natural atmospheric variability due to imperfect co-locations. This work is the first attempt to quantify this atmospheric variability for a large sample of atmospheric constituents and to provide the user with a tool to substract the natural atmospheric variability portion from the residual variability.
Edward Malina, Ben Veihelmann, Matthias Buschmann, Nicholas M. Deutscher, Dietrich G. Feist, and Isamu Morino
Atmos. Meas. Tech., 15, 2377–2406, https://doi.org/10.5194/amt-15-2377-2022, https://doi.org/10.5194/amt-15-2377-2022, 2022
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Methane retrievals from remote sensing instruments are fundamentally based on spectroscopic parameters, which indicate spectral-line positions, and their characteristics. These parameters are stored in several databases that vary in their make-up. Here we assess how concentrations of methane isotopologues measured from the same Total Carbon Column Observing Network (TCCON) instruments vary across a range of spectral windows using different spectroscopic databases and comment on the implications.
David A. Newnham, Mark A. Clilverd, William D. J. Clark, Michael Kosch, Pekka T. Verronen, and Alan E. E. Rogers
Atmos. Meas. Tech., 15, 2361–2376, https://doi.org/10.5194/amt-15-2361-2022, https://doi.org/10.5194/amt-15-2361-2022, 2022
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Ozone (O3) is an important trace gas in the mesosphere and lower thermosphere (MLT), affecting heating rates and chemistry. O3 profiles measured by the Ny-Ålesund Ozone in the Mesosphere Instrument agree with Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) for winter night-time, but autumn twilight SABER abundances are up to 50 % higher. O3 abundances in the MLT from two different SABER channels also show significant differences for both autumn twilight and summer daytime.
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, https://doi.org/10.5194/acp-22-4779-2022, https://doi.org/10.5194/acp-22-4779-2022, 2022
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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.
Piera Raspollini, Enrico Arnone, Flavio Barbara, Massimo Bianchini, Bruno Carli, Simone Ceccherini, Martyn P. Chipperfield, Angelika Dehn, Stefano Della Fera, Bianca Maria Dinelli, Anu Dudhia, Jean-Marie Flaud, Marco Gai, Michael Kiefer, Manuel López-Puertas, David P. Moore, Alessandro Piro, John J. Remedios, Marco Ridolfi, Harjinder Sembhi, Luca Sgheri, and Nicola Zoppetti
Atmos. Meas. Tech., 15, 1871–1901, https://doi.org/10.5194/amt-15-1871-2022, https://doi.org/10.5194/amt-15-1871-2022, 2022
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The MIPAS instrument onboard the ENVISAT satellite provided 10 years of measurements of the atmospheric emission al limb that allow for the retrieval of latitude- and altitude-resolved atmospheric composition. We describe the improvements implemented in the retrieval algorithm used for the full mission reanalysis, which allows for the generation of the global distributions of 21 atmospheric constituents plus temperature with increased accuracy with respect to previously generated data.
Patrick E. Sheese, Kaley A. Walker, Chris D. Boone, Adam E. Bourassa, Doug A. Degenstein, Lucien Froidevaux, C. Thomas McElroy, Donal Murtagh, James M. Russell III, and Jiansheng Zou
Atmos. Meas. Tech., 15, 1233–1249, https://doi.org/10.5194/amt-15-1233-2022, https://doi.org/10.5194/amt-15-1233-2022, 2022
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This study analyzes the quality of two versions (v3.6 and v4.1) of ozone concentration measurements from the ACE-FTS (Atmospheric Chemistry Experiment Fourier Transform Spectrometer), by comparing with data from five satellite instruments between 2004 and 2020. It was found that although the v3.6 data exhibit a better agreement than v4.1 with respect to the other instruments, v4.1 exhibits much better stability over time than v3.6. The stability of v4.1 makes it suitable for ozone trend studies.
Sheena Loeffel, Roland Eichinger, Hella Garny, Thomas Reddmann, Frauke Fritsch, Stefan Versick, Gabriele Stiller, and Florian Haenel
Atmos. Chem. Phys., 22, 1175–1193, https://doi.org/10.5194/acp-22-1175-2022, https://doi.org/10.5194/acp-22-1175-2022, 2022
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SF6-derived trends of stratospheric AoA from observations and model simulations disagree in sign. SF6 experiences chemical degradation, which we explicitly integrate in a global climate model. In our simulations, the AoA trend changes sign when SF6 sinks are considered; thus, the process has the potential to reconcile simulated with observed AoA trends. We show that the positive AoA trend is due to the SF6 sinks themselves and provide a first approach for a correction to account for SF6 loss.
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, https://doi.org/10.5194/acp-22-903-2022, https://doi.org/10.5194/acp-22-903-2022, 2022
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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.
Bianca Maria Dinelli, Piera Raspollini, Marco Gai, Luca Sgheri, Marco Ridolfi, Simone Ceccherini, Flavio Barbara, Nicola Zoppetti, Elisa Castelli, Enzo Papandrea, Paolo Pettinari, Angelika Dehn, Anu Dudhia, Michael Kiefer, Alessandro Piro, Jean-Marie Flaud, Manuel López-Puertas, David Moore, John Remedios, and Massimo Bianchini
Atmos. Meas. Tech., 14, 7975–7998, https://doi.org/10.5194/amt-14-7975-2021, https://doi.org/10.5194/amt-14-7975-2021, 2021
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The level-2 v8 database from the measurements of the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS), aboard the European Space Agency Envisat satellite, containing atmospheric fields of pressure, temperature, and volume mixing ratio of 21 trace gases, is described in this paper. The database covers all the measurements acquired by MIPAS (from July 2002 to April 2012). The number of species included makes it of particular importance for the studies of stratospheric chemistry.
Michael Höpfner, Oliver Kirner, Gerald Wetzel, Björn-Martin Sinnhuber, Florian Haenel, Sören Johansson, Johannes Orphal, Roland Ruhnke, Gabriele Stiller, and Thomas von Clarmann
Atmos. Chem. Phys., 21, 18433–18464, https://doi.org/10.5194/acp-21-18433-2021, https://doi.org/10.5194/acp-21-18433-2021, 2021
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BrONO2 is an important reservoir gas for inorganic stratospheric bromine linked to the chemical cycles of stratospheric ozone depletion. Presently infrared limb sounding is the only way to measure BrONO2 in the atmosphere. We provide global distributions of BrONO2 derived from MIPAS observations 2002–2012. Comparisons with EMAC atmospheric modelling show an overall agreement and enable us to derive an independent estimate of stratospheric bromine of 21.2±1.4pptv based on the BrONO2 measurements.
Frank Werner, Nathaniel J. Livesey, Michael J. Schwartz, William G. Read, Michelle L. Santee, and Galina Wind
Atmos. Meas. Tech., 14, 7749–7773, https://doi.org/10.5194/amt-14-7749-2021, https://doi.org/10.5194/amt-14-7749-2021, 2021
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In this study we present an improved cloud detection scheme for the Microwave Limb Sounder, which is based on a feedforward artificial neural network. This new algorithm is shown not only to reliably detect high and mid-level convection containing even small amounts of cloud water but also to distinguish between high-reaching and mid-level to low convection.
Tyler Wizenberg, Kimberly Strong, Kaley Walker, Erik Lutsch, Tobias Borsdorff, and Jochen Landgraf
Atmos. Meas. Tech., 14, 7707–7728, https://doi.org/10.5194/amt-14-7707-2021, https://doi.org/10.5194/amt-14-7707-2021, 2021
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CO is an important atmospheric gas that influences both air quality and the climate. Here, we compare CO measurements from TROPOMI with those from ACE-FTS and an Arctic ground-based FTS at Eureka, Nunavut, to further characterize the accuracy of TROPOMI measurements. CO columns from the instruments agree well but show larger differences at high latitudes. Despite this, the results fall within the TROPOMI accuracy target, indicating good data quality at high latitudes.
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, https://doi.org/10.5194/acp-21-16645-2021, https://doi.org/10.5194/acp-21-16645-2021, 2021
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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.
Nathaniel J. Livesey, William G. Read, Lucien Froidevaux, Alyn Lambert, Michelle L. Santee, Michael J. Schwartz, Luis F. Millán, Robert F. Jarnot, Paul A. Wagner, Dale F. Hurst, Kaley A. Walker, Patrick E. Sheese, and Gerald E. Nedoluha
Atmos. Chem. Phys., 21, 15409–15430, https://doi.org/10.5194/acp-21-15409-2021, https://doi.org/10.5194/acp-21-15409-2021, 2021
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The Microwave Limb Sounder (MLS), an instrument on NASA's Aura mission launched in 2004, measures vertical profiles of the temperature and composition of Earth's "middle atmosphere" (the region from ~12 to ~100 km altitude). We describe how, among the 16 trace gases measured by MLS, the measurements of water vapor (H2O) and nitrous oxide (N2O) have started to drift since ~2010. The paper also discusses the origins of this drift and work to ameliorate it in a new version of the MLS dataset.
Pekka T. Verronen, Antti Kero, Noora Partamies, Monika E. Szeląg, Shin-Ichiro Oyama, Yoshizumi Miyoshi, and Esa Turunen
Ann. Geophys., 39, 883–897, https://doi.org/10.5194/angeo-39-883-2021, https://doi.org/10.5194/angeo-39-883-2021, 2021
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This paper is the first to simulate and analyse the pulsating aurorae impact on middle atmosphere on monthly/seasonal timescales. We find that pulsating aurorae have the potential to make a considerable contribution to the total energetic particle forcing and increase the impact on upper stratospheric odd nitrogen and ozone in the polar regions. Thus, it should be considered in atmospheric and climate simulations.
David E. Siskind, V. Lynn Harvey, Fabrizio Sassi, John P. McCormack, Cora E. Randall, Mark E. Hervig, and Scott M. Bailey
Atmos. Chem. Phys., 21, 14059–14077, https://doi.org/10.5194/acp-21-14059-2021, https://doi.org/10.5194/acp-21-14059-2021, 2021
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General circulation models have had a very difficult time simulating the descent of nitric oxide through the polar mesosphere to the stratosphere. Here, we present results suggesting that, with the proper specification of middle atmospheric meteorology, the simulation of this process can be greatly improved. Despite differences in the detailed geographic morphology of the model NO as compared with satellite data, we show that the overall abundance is likely in good agreement with the data.
Francesco Grieco, Kristell Pérot, Donal Murtagh, Patrick Eriksson, Bengt Rydberg, Michael Kiefer, Maya Garcia-Comas, Alyn Lambert, and Kaley A. Walker
Atmos. Meas. Tech., 14, 5823–5857, https://doi.org/10.5194/amt-14-5823-2021, https://doi.org/10.5194/amt-14-5823-2021, 2021
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We present improved Odin/SMR mesospheric H2O concentration and temperature data sets, reprocessed assuming a bigger sideband leakage of the instrument. The validation study shows how the improved SMR data sets agree better with other instruments' observations than the old SMR version did. Given their unique time extension and geographical coverage, and H2O being a good tracer of mesospheric circulation, the new data sets are valuable for the study of dynamical processes and multi-year trends.
Ilya Stanevich, Dylan B. A. Jones, Kimberly Strong, Martin Keller, Daven K. Henze, Robert J. Parker, Hartmut Boesch, Debra Wunch, Justus Notholt, Christof Petri, Thorsten Warneke, Ralf Sussmann, Matthias Schneider, Frank Hase, Rigel Kivi, Nicholas M. Deutscher, Voltaire A. Velazco, Kaley A. Walker, and Feng Deng
Atmos. Chem. Phys., 21, 9545–9572, https://doi.org/10.5194/acp-21-9545-2021, https://doi.org/10.5194/acp-21-9545-2021, 2021
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We explore the utility of a weak-constraint (WC) four-dimensional variational (4D-Var) data assimilation scheme for mitigating systematic errors in methane simulation in the GEOS-Chem model. We use data from the Greenhouse Gases Observing Satellite (GOSAT) and show that, compared to the traditional 4D-Var approach, the WC scheme improves the agreement between the model and independent observations. We find that the WC corrections to the model provide insight into the source of the errors.
Thomas von Clarmann, Udo Grabowski, Gabriele P. Stiller, Beatriz M. Monge-Sanz, Norbert Glatthor, and Sylvia Kellmann
Atmos. Chem. Phys., 21, 8823–8843, https://doi.org/10.5194/acp-21-8823-2021, https://doi.org/10.5194/acp-21-8823-2021, 2021
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Measurements of long-lived trace gases (SF6, CFC-11, CFC-12, HCFC-12, CCl4, N2O, CH4, H2O, and CO) performed with the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) have been used to infer the stratospheric and mesospheric meridional circulation. The MIPAS data set covers the time period from July 2002 to April 2012. The method used for this purpose was the direct inversion of the two-dimensional continuity equation. Multiannual monthly mean circulation fields are presented.
Michael Kiefer, Thomas von Clarmann, Bernd Funke, Maya García-Comas, Norbert Glatthor, Udo Grabowski, Sylvia Kellmann, Anne Kleinert, Alexandra Laeng, Andrea Linden, Manuel López-Puertas, Daniel R. Marsh, and Gabriele P. Stiller
Atmos. Meas. Tech., 14, 4111–4138, https://doi.org/10.5194/amt-14-4111-2021, https://doi.org/10.5194/amt-14-4111-2021, 2021
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An improved dataset of vertical temperature profiles of the Earth's atmosphere in the altitude range 5–70 km is presented. These profiles are derived from measurements of the MIPAS instrument onboard ESA's Envisat satellite. The overall improvements are based on upgrades in the input data and several improvements in the data processing approach. Both of these are discussed, and an extensive error discussion is included. Enhancements of the new dataset are demonstrated by means of examples.
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Short summary
We present a new global dataset of ozone profiles in the mesosphere and lower thermosphere, created by combining several satellite measurements covering more than three decades. Our results show that ozone is recovering in the stratosphere but decreasing in the mesosphere, with the strongest declines near the mesopause. This dataset provides a valuable resource for investigating long-term changes, improving model performance, and addressing an observational gap in the upper atmosphere.
We present a new global dataset of ozone profiles in the mesosphere and lower thermosphere,...
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