COVID-19 Crisis Reduces Free Tropospheric Ozone across the Northern Hemisphere

Wolfgang Steinbrecht (1) , Dagmar Kubistin (1) , Christian Plass-Dülmer (1) , Jonathan Davies (2) , David W. Tarasick (2) , Peter von Der Gathen (3) , Holger Deckelmann (3) , Nis Jepsen (4) , Rigel Kivi (5) , Norrie Lyall (6) , Matthias Palm (7) , Justus Notholt (7) , Bogumil Kois (8) , Peter Oelsner (1) , Marc Allaart (9) , Ankie Piters (9) , Michael Gill (10) , Roeland van Malderen (11) , Andy W. Delcloo (11) , Ralf Sussmann (12) , Emmanuel Mahieu (13) , Christian Servais (13) , Gonzague Romanens (14) , Rene Stübi (14) , Gérard Ancellet (15) , Sophie Godin-Beekmann (16) , Shoma Yamanouchi (17) , Kimberly Strong (17) , Bryan Johnson (18) , Patrick Cullis (18, 19) , Irina Petropavlovskikh (19, 18) , James W. Hannigan (20) , Jose-Luis Hernandez (21) , Ana Diaz Rodriguez (21) , Tatsumi Nakano (22) , Fernando Chouza (23) , Thierry Leblanc (23) , Carlos Torres (21) , Omaira Garcia (21) , Amelie N. Röhling (24) , Matthias Schneider (24) , Thomas Blumenstock (24) , Matt Tully (25) , Clare Paton-Walsh (26) , Nicholas Jones (26) , Richard Querel (27) , Susan Strahan (28) , Ryan M. Stauffer (29, 28) , Anne M. Thompson (28) , Antje Inness (30) , Richard Engelen (30) , Kai-Lan Chang (31, 19) , Owen R. Cooper (31, 19)

1 DWD - Deutscher Wetterdienst [Offenbach]
2 Environment and Climate Change Canada
3 AWI - Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung
4 DMI - Danish Meteorological Institute
5 FMI - Finnish Meteorological Institute
6 Met Office Lerwick
7 Universität Bremen
8 IMGW - PIB - Institute of Meteorology and Water Management - National Research Institute
9 KNMI - Royal Netherlands Meteorological Institute
10 MET ÉIREANN - Irish Meteorological Service
11 IRM - Institut Royal Météorologique de Belgique [Bruxelles] - Royal Meteorological Institute
12 IMK-IFU - Institut für Meteorologie und Klimaforschung - Atmosphärische Umweltforschung
13 Institut d'Astrophysique et de Géophysique [Liège]
14 Federal Office of Meteorology and Climatology MeteoSwiss
15 TROPO - LATMOS
16 STRATO - LATMOS
17 University of Toronto
18 GML - ESRL Global Monitoring Laboratory [Boulder]
19 CIRES - Cooperative Institute for Research in Environmental Sciences
20 NCAR - National Center for Atmospheric Research [Boulder]
21 AEMet - Agencia Estatal de Meteorología
22 MRI - Meteorological Research Institute [Tsukuba]
23 JPL - Jet Propulsion Laboratory
24 IMK-ASF - Institut für Meteorologie und Klimaforschung - Atmosphärische Spurengase und Fernerkundung
25 BoM - Australian Bureau of Meteorology [Melbourne]
26 University of Wollongong [Australia]
27 NIWA - National Institute of Water and Atmospheric Research [Lauder]
28 GSFC Earth Sciences Division
29 ESSIC - Earth Science System Interdisciplinary Center [College Park]
30 ECMWF - European Centre for Medium-Range Weather Forecasts
31 CSL - NOAA Chemical Sciences Laboratory

Throughout spring and summer 2020, ozone stations in the northern extratropics recorded unusually low ozone in the free troposphere. From April to August, and from 1 to 8 kilometers altitude, ozone was on average 7% (≈4 nmol/mol) below the 2000 to 2020 climatological mean. Such low ozone, over several months, and at so many stations, has not been observed in any previous year since at least 2000. Atmospheric composition analyses from the Copernicus Atmosphere Monitoring Service and simulations from the NASA GMI model indicate that the large 2020 springtime ozone depletion in the Arctic stratosphere contributed less than one quarter of the observed tropospheric anomaly. The observed anomaly is consistent with recent chemistry‐climate model simulations, which assume emissions reductions similar to those caused by the COVID‐19 crisis. COVID‐19 related emissions reductions appear to be the major cause for the observed reduced free tropospheric ozone in 2020.

Keywords: Emissions; Troposphere; Ozone; COVID‐19

Domains: Atmospheric and Oceanic Physics [physics.ao-ph]; Ocean, Atmosphere; Infectious diseases; Pulmonology and respiratory tract

Wolfgang Steinbrecht, Dagmar Kubistin, Christian Plass-Dülmer, Jonathan Davies, David W. Tarasick, et al.. COVID-19 Crisis Reduces Free Tropospheric Ozone across the Northern Hemisphere. Geophysical Research Letters, 2021, 48 (5), pp.e2020GL091987. ⟨10.1029/2020GL091987⟩. ⟨insu-03137114v2⟩