EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

Near‐Complete Local Reduction of Arctic Stratospheric Ozone by Severe Chemical Loss in Spring 2020

Ingo Wohltmann1, Peter von der Gathen1, Ralph Lehmann1, Marion Maturilli1, Holger Deckelmann1, Gloria Manney2,3, Jonathan Davies4, David Tarasick4, Nis Jepsen5, Rigel Kivi6, Norrie Lyall7, and Markus Rex1
Ingo Wohltmann et al.
  • 1Stiftung Alfred Wegener Institut für Polar und Meeresforschung, Forschungsstelle Potsdam, Potsdam, Germany (
  • 2NorthWest Research Associates, Socorro, NM, USA
  • 3New Mexico Institute of Mining and Technology, Socorro, NM, USA
  • 4Air Quality Research Division, Environment and Climate Change Canada, Downsview, Ontario, Canada
  • 5Danish Meteorological Institute, Copenhagen, Denmark
  • 6Space and Earth Observation Centre, Finnish Meteorological Institute, Sodankylä, Finland
  • 7Lerwick Observatory, UK Met Office, Shetland Islands, UK

In the Antarctic ozone hole, ozone mixing ratios have been decreasing to extremely low values of 0.01–0.1 ppm in nearly all spring seasons since the late 1980s, corresponding to 95–99% local chemical loss. In contrast, Arctic ozone loss has been much more limited and mixing ratios have never before fallen below 0.5 ppm. In Arctic spring 2020, however, ozonesonde measurements in the most depleted parts of the polar vortex show a highly depleted layer, with ozone loss averaged over sondes peaking at 93% at 18 km. Typical minimum mixing ratios of 0.2 ppm were observed, with individual profiles showing values as low as 0.13 ppm (96% loss). The reason for the unprecedented chemical loss was an unusually strong, long-lasting, and cold polar vortex, showing that for individual winters the effect of the slow decline of ozone-depleting substances on ozone depletion may be counteracted by low temperatures.

How to cite: Wohltmann, I., von der Gathen, P., Lehmann, R., Maturilli, M., Deckelmann, H., Manney, G., Davies, J., Tarasick, D., Jepsen, N., Kivi, R., Lyall, N., and Rex, M.: Near‐Complete Local Reduction of Arctic Stratospheric Ozone by Severe Chemical Loss in Spring 2020, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-2699,, 2021.

Corresponding presentation materials formerly uploaded have been withdrawn.