MLS Research

Stratospheric Polar Processes and Ozone

Contact Michelle Santee

One of the overarching goals of the Aura mission is to track the stability of the stratospheric ozone layer. At issue is whether global stratospheric ozone will recover as anticipated as the abundances of ozone-depleting substances decline in response to international regulations.

The primary agent responsible for the formation of the ozone hole that forms over Antarctica every austral spring is anthropogenic chlorine. Stratospheric chlorine loading is presently near its peak but waning; assuming compliance with existing protocols, it should return to pre-1980 levels by about 2050.

Although detection and attribution of small changes in chlorine-catalyzed ozone loss are challenging problems, some abatement of lower stratospheric polar ozone depletion may become apparent during the Aura timeframe. There are, however, important linkages between climate change and ozone depletion that could delay recovery of the ozone layer. Changes in stratospheric temperature, humidity, and circulation patterns brought about by climate change could exacerbate polar ozone destruction processes. These issues are of particular concern in the Arctic, where wintertime temperatures often hover near the thresholds at which the processes leading to severe chlorine-catalyzed ozone destruction are triggered.

Aura MLS measures vertical profiles of many of the key species involved in polar processing and ozone loss in the lower stratosphere. In addition to temperature and ozone itself, MLS is providing the first simultaneous, collocated daily global measurements of both ClO, the primary form of reactive (ozone-destroying) chlorine in the stratosphere, and HCl, the main stratospheric chlorine reservoir (relatively inactive) species. MLS also measures two other minor chlorine species, HOCl and (in version 3) CH3Cl (the only significant natural source of organic chlorine).

In addition, MLS measures H2O and HNO3, the main components of the polar stratospheric clouds that form in the very low temperatures in the winter polar regions in both hemispheres; these cloud particles provide surfaces on which the heterogeneous chemical reactions that convert reservoir chlorine to reactive forms can take place, thus priming the atmosphere for severe ozone destruction.

N2O and CO are "tracers" of stratospheric air motions; MLS measurements of these species provide critical information needed to disentangle the effects of transport and mixing from those of chemical loss on the observed ozone distributions. Other MLS measurements that are arguably relevant for lower stratospheric polar processes and ozone loss include volcanic SO2 (for helping diagnose the influence of major volcanic eruptions on the ozone layer), and HCN, CH3CN, and cloud ice water content in the upper troposphere (for helping assess the impact of pollutants and other species lofted from below that may affect ozone chemistry in the stratosphere).

MLS-related publications concerning polar stratospheric ozone

  1. Petropavlovskikh, I., K. Miyagawa, A. McClure-Beegle, B. Johnson, J. Wild, S. Strahan, K. Wargan, R. Querel, L. Flynn, E. Beach, G. Ancellet and S. Godin-Beekmann
    Optimized Umkehr profile algorithm for ozone trend analyses
    Atmos. Chem. Phys. Discuss. doi:10.5194/amt-2021-203, in review
  2. Rawat, P., M. Naja, E. Fishbein, P. Thapliyal, R. Kumar, P. Bhardwaj, A. Jaiswal, S. Tiwari, S. Venkataramani and S. Lal
    Performance of AIRS ozone retrieval over the central Himalayas: Case studies of biomass burning, downward ozone transport and radiative forcing using long-term observations
    Atmospheric Measurement Techniques Discussions doi:10.5194/amt-2022-187, in review
  3. Shi, G., W. Krochin, E. Sauvageat and G. Stober
    Ozone and water vapor variability in the polar middle atmosphere observed with ground-based microwave radiometers
    Environmental Science and Pollution Research in review
  4. Vogel, A., J. Ungermann and H. Elbern
    Analyzing trace gas filaments in the Ex-UTLS by 4D-variationalassimilation of airborne tomographic retrievals
    Atmos. Chem. Phys. Discuss. doi:10.5194/acp-2017-308, in review
  5. Roy, C., A.R. Ravishankara, P. Newman, L. David, S. Fadnavis, S. Rathod, L. Lait, R. Krishnan, H. Clark and B. Sauvage
    Estimation of Stratospheric Intrusions During Indian Cyclones
    Journal of Geophysical Research: Atmospheres doi:10.1029/2022jd037519, 2023
  6. Solomon, S., K. Stone, P. Yu, D.M. Murphy, D. Kinnison, A.R. Ravishankara and P. Wang
    Chlorine activation and enhanced ozone depletion induced by wildfire aerosol
  7. Tencé, F., J. Jumelet, M. Bouillon, D. Cugnet, S. Bekki, S. Safieddine, P. Keckhut and A. Sarkissian
    14 years of lidar measurements of polar stratospheric clouds at the French Antarctic station Dumont d'Urville
    Atmos. Chem. Phys. doi:10.5194/acp-23-431-2023, 2023
  8. Wang, P., S. Solomon and K. Stone
    Stratospheric chlorine processing after the 2020 Australian wildfires derived from satellite data
    Proc. Nat. Acad. Sci. doi:10.1073/pnas.2213910120, 2023
  9. Ardra, D., J. Kuttippurath, R. Roy, P. Kumar, S. Raj, R. Müller and W. Feng
    The Unprecedented Ozone Loss in the Arctic Winter and Spring of 2010/2011 and 2019/2020
    ACS Earth and Space Chemistry doi:10.1021/acsearthspacechem.1c00333, 2022
  10. Barras, E.M., A. Haefele, R. Stübi, A. Jouberton, H. Schill, I. Petropavlovskikh, K. Miyagawa, M. Stanek and L. Froidevaux
    Dynamical linear modeling estimates of long-term ozone trends from homogenized Dobson Umkehr profiles at Arosa/Davos, Switzerland
    Atmos. Chem. Phys. doi:10.5194/acp-22-14283-2022, 2022
  11. Benito-Barca, S., N. Calvo and M. Abalos
    Driving mechanisms for the El Niño–Southern Oscillation impact on stratospheric ozone
    Atmos. Chem. Phys. 10.5194/acp-22-15729-2022, 2022
  12. Blunden, J. and T. Boyer
    State of the Climate in 2021
    Bull. Am. Meteorol. Soc. doi:10.1175/2022bamsstateoftheclimate.1, 2022
  13. Dutta, R., S. S. and S. Ojha
    Impact of stratospheric planetary wave and ozone variabilities on the austral polar middle atmospheric circulation
    Adv. Space Res. doi:10.1016/j.asr.2022.01.025, 2022
  14. Eswaraiah, S., K. Seo, K. Kumar, M. Ratnam, A. Koval, J. Jeong, C. Mengist, Y. Lee, K. Greer, J. Hwang, W. Lee, M. Pramitha, G.V. Chalapathi, M.V. Reddy and Y. Kim
    Anthropogenic Influence on the Antarctic Mesospheric Cooling Observed during the Southern Hemisphere Minor Sudden Stratospheric Warming
    Atmosphere doi:10.3390/atmos13091475, 2022
  15. Fujiwara, M., G.L. Manney, L.J. Gray and J.S. Wright
    SPARC Reanalysis Intercomparison Project S-RIP Final Report
    n/a 2022
  16. Hulswar, S., P. Mohite and A. Mahajan
    Quantifying stratospheric ozone loss over Antarctica in the last two decades using corrected satellite profiles
    Polar Science doi:10.1016/j.polar.2022.100860, 2022
  17. Lee, H., T. Choi, S. Kim, J. Bak, D. Ahn, N. Kramarova, S. Park, J. Kim and J. Koo
    Validations of satellite ozone profiles in austral spring using ozonesonde measurements in the Jang Bogo station, Antarctica
    Environmental Research doi:10.1016/j.envres.2022.114087, 2022
  18. Li, Y., S. Dhomse, M. Chipperfield, W. Feng, A. Chrysanthou, Y. Xia and D. Guo
    Effects of reanalysis forcing fields on ozone trends and age of air from a chemical transport model
    Atmos. Chem. Phys. doi:10.5194/acp-22-10635-2022, 2022
  19. Roy, R., J. Kuttippurath, F. Lefèvre, S. Raj and P. Kumar
    The sudden stratospheric warming and chemical ozone loss in the Antarctic winter 2019: comparison with the winters of 1988 and 2002
    Theoretical and Applied Climatology doi:10.1007/s00704-022-04031-6, 2022
  20. Salawitch, R. and L. McBride
    Australian wildfires depleted the ozone layer
  21. Santee, M.L., A. Lambert, G.L. Manney, N.J. Livesey, L. Froidevaux, J.L. Neu, M.J. Schwartz, L.F. Millán, F. Werner, W.G. Read, M. Park, R.A. Fuller and B.M. Ward
    Prolonged and Pervasive Perturbations in the Composition of the Southern Hemisphere Midlatitude Lower Stratosphere From the Australian New Year's Fires
    Geophys. Res. Lett. doi:10.1029/2021gl096270, 2022
  22. Shams, S.B., V. Walden, J. Hannigan, W. Randel, I. Petropavlovskikh, A. Butler and A.D.l. Cámara
    Analyzing ozone variations and uncertainties at high latitudes during sudden stratospheric warming events using MERRA-2
    Atmos. Chem. Phys. doi:10.5194/acp-22-5435-2022, 2022
  23. Stauffer, R., A. Thompson, D. Kollonige, D. Tarasick, R.V. Malderen, H. Smit, H. Vömel, G. Morris, B. Johnson, P. Cullis, R. Stübi, J. Davies and M. Yan
    An Examination of the Recent Stability of Ozonesonde Global Network Data
    Earth and Space Science doi:10.1029/2022ea002459, 2022
  24. Strahan, S., L. Coy, A. Douglass and M. Damon
    Faster Tropical Upper Stratospheric Upwelling Drives Changes in Ozone Chemistry
    Geophys. Res. Lett. doi:10.1029/2022gl101075, 2022
  25. Strahan, S., D. Smale, S. Solomon, G. Taha, M. Damon, S. Steenrod, N. Jones, B. Liley, R. Querel and J. Robinson
    Unexpected Repartitioning of Stratospheric Inorganic Chlorine After the 2020 Australian Wildfires
    Geophys. Res. Lett. doi:10.1029/2022gl098290, 2022
  26. Sullivan, J., A. Apituley, N. Mettig, K. Kreher, K.E. Knowland, M. Allaart, A. Piters, M.V. Roozendael, P. Veefkind, J. Ziemke, N. Kramarova, M. Weber, A. Rozanov, L. Twigg, G. Sumnicht and T. McGee
    Tropospheric and stratospheric ozone profiles during the 2019 TROpomi vaLIdation eXperiment TROLIX-19
    Atmos. Chem. Phys. doi:10.5194/acp-22-11137-2022, 2022
  27. Wespes, C., G. Ronsmans, L. Clarisse, S. Solomon, D. Hurtmans, C. Clerbaux and P. Coheur
    Polar stratospheric nitric acid depletion surveyed from a decadal dataset of IASI total columns
    Atmos. Chem. Phys. doi:10.5194/acp-22-10993-2022, 2022
  28. Xiong, X., X. Liu, W. Wu, K.E. Knowland, Q. Yang, J. Welsh and D. Zhou
    Satellite observation of stratospheric intrusions and ozone transport using CrIS on SNPP
    Atmospheric Environment doi:10.1016/j.atmosenv.2022.118956, 2022
  29. Aabaribaoune, M.E., E. Emili and V. Guidard
    Estimation of the error covariance matrix for IASI radiances and its impact on the assimilation of ozone in a chemistry transport model
    Atmospheric Measurement Techniques doi:10.5194/amt-14-2841-2021, 2021
  30. Bazhenov, O.E., A.A. Nevzorov, A.V. Nevzorov, S.I. Dolgii and A.P. Makeev
    Disturbance of the Stratosphere over Tomsk prior to the 2018 Major Sudden Stratospheric Warming: Effect of ClO Dimer Cycle
    Optical Memory and Neural Networks doi:10.3103/s1060992x21020065, 2021
  31. Blunden, J. and T. Boyer
    State of the Climate in 2020
    Bull. Am. Meteorol. Soc. doi:10.1175/2021bamsstateoftheclimate.1, 2021
  32. Dhomse, S., C. Arosio, W. Feng, A. Rozanov, M. Weber and M. Chipperfield
    ML-TOMCAT: machine-learning-based satellite-corrected global stratospheric ozone profile data set from a chemical transport model
    Earth System Science Data 10.5194/essd-13-5711-2021, 2021
  33. Dietmüller, S., H. Garny, R. Eichinger and W. Ball
    Analysis of recent lower-stratospheric ozone trends in chemistry climate models
    Atmos. Chem. Phys. doi:10.5194/acp-21-6811-2021, 2021
  34. Emili, E. and M.E. Aabaribaoune
    Impact of Infrared Atmospheric Sounding Interferometer IASI thermal infrared measurements on global ozone reanalyses
    Geoscientific Model Development doi:10.5194/gmd-14-6291-2021, 2021
  35. Feng, W., S. Dhomse, C. Arosio, M. Weber, J. Burrows, M. Santee and M. Chipperfield
    Arctic Ozone Depletion in 2019/20: Roles of Chemistry, Dynamics and the Montreal Protocol
    Geophys. Res. Lett. doi:10.1029/2020gl091911, 2021
  36. Gharibzadeh, M., A. Bidokhti and K. Alam
    The interaction of ozone and aerosol in a semi-arid region in the Middle East: Ozone formation and radiative forcing implications
    Atmospheric Environment doi:10.1016/j.atmosenv.2020.118015, 2021
  37. Gordon, E., A. Seppälä, B. Funke, J. Tamminen and K. Walker
    Observational evidence of energetic particle precipitation NOx (EPP-NOx) interaction with chlorine curbing Antarctic ozone loss
    Atmos. Chem. Phys. doi:10.5194/acp-21-2819-2021, 2021
  38. Grooß, J. and R. Müller
    Simulation of Record Arctic Stratospheric Ozone Depletion in 2020
    Journal of Geophysical Research: Atmospheres doi:10.1029/2020jd033339, 2021
  39. Hu, D., Z. Guan, M. Liu and W. Feng
    Dynamical mechanisms for the recent ozone depletion in the Arctic stratosphere linked to North Pacific sea surface temperatures
    Climate Dynamics doi:10.1007/s00382-021-06026-x, 2021
  40. Hulswar, S., P. Mohite, V. Soni and A. Mahajan
    Differences between in-situ ozonesonde observations and satellite retrieved ozone vertical profiles across Antarctica
    Polar Science doi:10.1016/j.polar.2021.100688, 2021
  41. Jenkins, G., V.D. Castro, B. Cunha, I. Fontanez and R. Holzworth
    The Evolution of the Wave‐One Ozone Maximum During the 2017 LASIC Field Campaign at Ascension Island
    Journal of Geophysical Research: Atmospheres doi:10.1029/2020jd033972, 2021
  42. Karpowicz, B., W. McCarty and K. Wargan
    Investigating the utility of hyperspectral sounders in the 9.6 μm band to improve ozone analyses
    Q. J. Roy. Meteorol. Soc. doi:10.1002/qj.4198, 2021
  43. Keeble, J., B. Hassler, A. Banerjee, R. Checa-Garcia, G. Chiodo, S. Davis, V. Eyring, P. Griffiths, O. Morgenstern, P. Nowack, G. Zeng, J. Zhang, G. Bodeker, S. Burrows, P. Cameron-Smith, D. Cugnet, C. Danek, M. Deushi, L. Horowitz, A. Kubin, L. Li, G. Lohmann, M. Michou, M. Mills, P. Nabat, D. Olivié, S. Park, O. Seland, J. Stoll, K. Wieners and T. Wu
    Evaluating stratospheric ozone and water vapour changes in CMIP6 models from 1850 to 2100
    Atmos. Chem. Phys. doi:10.5194/acp-21-5015-2021, 2021
  44. Kumar, K., B. Singh and Kumar, K.
    Intriguing aspects of Asian Summer Monsoon Anticyclone Ozone variability from Microwave Limb Sounder measurements
    Atmos. Res. 10.1016/j.atmosres.2021.105479, 2021
  45. Kuttippurath, J., W. Feng, R. Müller, P. Kumar, S. Raj, G. Gopikrishnan and R. Roy
    Exceptional loss in ozone in the Arctic winter/spring of 2019/2020
    Atmos. Chem. Phys. doi:10.5194/acp-21-14019-2021, 2021
  46. Liu, M. and D. Hu
    Contrast relationships between Arctic Oscillation and ozone in the stratosphere over the Arctic in early and mid‐to‐late winter
    Journal of Geophysical Research: Atmospheres doi:10.1029/2020jd033426, 2021
  47. Lu, J., F. Xie, H. Tian and J. Luo
    Impacts of Ozone Changes in the Tropopause Layer on Stratospheric Water Vapor
    Atmosphere doi:10.3390/atmos12030291, 2021
  48. Rieger, L.A., W.J. Randel, A.E. Bourassa and S. Solomon
    Stratospheric Temperature and Ozone Anomalies Associated With the 2020 Australian New Year Fires
    Geophys. Res. Lett. doi:10.1029/2021gl095898, 2021
  49. Sepúlveda, E., R. Cordero, A. Damiani, S. Feron, J. Pizarro, F. Zamorano, R. Kivi, R. Sánchez, M. Yela, J. Jumelet, A. Godoy, J. Carrasco, J. Crespo, G. Seckmeyer, J. Jorquera, J. Carrera, B. Valdevenito, S. Cabrera, A. Redondas and P. Rowe
    Evaluation of Antarctic Ozone Profiles derived from OMPS-LP by using Balloon-borne Ozonesondes
    Scientific Reports doi:10.1038/s41598-021-81954-6, 2021
  50. Sofieva, V., M. Szeląg, J. Tamminen, E. Kyrölä, D. Degenstein, C. Roth, D. Zawada, A. Rozanov, C. Arosio, J. Burrows, M. Weber, A. Laeng, G. Stiller, T. von Clarmann, L. Froidevaux, N. Livesey, M. van Roozendael and C. Retscher
    Measurement report: regional trends of stratospheric ozone evaluated using the MErged GRIdded Dataset of Ozone Profiles MEGRIDOP
    Atmos. Chem. Phys. doi:10.5194/acp-21-6707-2021, 2021