COVID‐19 Crisis Reduces Free Tropospheric Ozone Across the Northern Hemisphere
Kubistin, Dagmar
Plass‐Dülmer, Christian
Davies, Jonathan
Tarasick, David W.
Gathen, Peter von der
Deckelmann, Holger
Jepsen, Nis
Kivi, Rigel
Lyall, Norrie
Palm, Matthias
Notholt, Justus
Kois, Bogumil
Oelsner, Peter
Allaart, Marc
Piters, Ankie
Gill, Michael
Van Malderen, Roeland
Delcloo, Andy W.
Sussmann, Ralf
Mahieu, Emmanuel
Servais, Christian
Romanens, Gonzague
Stübi, Rene
Ancellet, Gerard
Godin‐Beekmann, Sophie
Yamanouchi, Shoma
Strong, Kimberly
Johnson, Bryan
Cullis, Patrick
Petropavlovskikh, Irina
Hannigan, James W.
Hernandez, Jose‐Luis
Diaz Rodriguez, Ana
Nakano, Tatsumi
Chouza, Fernando
Leblanc, Thierry
Torres, Carlos
Garcia, Omaira
Röhling, Amelie N.
Schneider, Matthias
Blumenstock, Thomas
Tully, Matt
Paton‐Walsh, Clare
Jones, Nicholas
Querel, Richard
Strahan, Susan
Stauffer, Ryan M.
Thompson, Anne M.
Inness, Antje
Engelen, Richard
Chang, Kai‐Lan
Cooper, Owen R.
DOI: https://doi.org/10.23689/fidgeo-4331
Plass‐Dülmer, Christian; 1 Deutscher Wetterdienst Hohenpeißenberg Germany
Davies, Jonathan; 2 Environment and Climate Change Canada Toronto ONT Canada
Tarasick, David W.; 2 Environment and Climate Change Canada Toronto ONT Canada
Gathen, Peter von der; 3 Alfred Wegener Institut Helmholtz‐Zentrum für Polar‐ und Meeresforschung Potsdam Germany
Deckelmann, Holger; 3 Alfred Wegener Institut Helmholtz‐Zentrum für Polar‐ und Meeresforschung Potsdam Germany
Jepsen, Nis; 4 Danish Meteorological Institute Copenhagen Denmark
Kivi, Rigel; 5 Finnish Meteorological Institute Sodankylä Finland
Lyall, Norrie; 6 British Meteorological Service Lerwick UK
Palm, Matthias; 7 University of Bremen Bremen Germany
Notholt, Justus; 7 University of Bremen Bremen Germany
Kois, Bogumil; 8 Institute of Meteorology and Water Management Legionowo Poland
Oelsner, Peter; 9 Deutscher Wetterdienst Lindenberg Germany
Allaart, Marc; 10 Royal Netherlands Meteorological Institute DeBilt The Netherlands
Piters, Ankie; 10 Royal Netherlands Meteorological Institute DeBilt The Netherlands
Gill, Michael; 11 Met Éireann (Irish Met. Service) Valentia Ireland
Van Malderen, Roeland; 12 Royal Meteorological Institute of Belgium Uccle Belgium
Delcloo, Andy W.; 12 Royal Meteorological Institute of Belgium Uccle Belgium
Sussmann, Ralf; 13 Karlsruhe Institute of Technology IMK‐IFU Garmisch‐Partenkirchen Germany
Mahieu, Emmanuel; 14 Institute of Astrophysics and Geophysics University of Liège Liège Belgium
Servais, Christian; 14 Institute of Astrophysics and Geophysics University of Liège Liège Belgium
Romanens, Gonzague; 15 Federal Office of Meteorology and Climatology MeteoSwiss Payerne Switzerland
Stübi, Rene; 15 Federal Office of Meteorology and Climatology MeteoSwiss Payerne Switzerland
Ancellet, Gerard; 16 LATMOS Sorbonne Université‐UVSQ‐CNRS/INSU Paris France
Godin‐Beekmann, Sophie; 16 LATMOS Sorbonne Université‐UVSQ‐CNRS/INSU Paris France
Yamanouchi, Shoma; 17 University of Toronto Toronto ONT Canada
Strong, Kimberly; 17 University of Toronto Toronto ONT Canada
Johnson, Bryan; 18 NOAA ESRL Global Monitoring Laboratory Boulder CO USA
Cullis, Patrick; 18 NOAA ESRL Global Monitoring Laboratory Boulder CO USA
Petropavlovskikh, Irina; 18 NOAA ESRL Global Monitoring Laboratory Boulder CO USA
Hannigan, James W.; 20 National Center for Atmospheric Research Boulder CO USA
Hernandez, Jose‐Luis; 21 State Meteorological Agency (AEMET) Madrid Spain
Diaz Rodriguez, Ana; 21 State Meteorological Agency (AEMET) Madrid Spain
Nakano, Tatsumi; 22 Meteorological Research Institute Tsukuba Japan
Chouza, Fernando; 23 Jet Propulsion Laboratory California Institute of Technology Table Mountain Facility Wrightwood CA USA
Leblanc, Thierry; 23 Jet Propulsion Laboratory California Institute of Technology Table Mountain Facility Wrightwood CA USA
Torres, Carlos; 24 Izaña Atmospheric Research Center AEMET Tenerife Spain
Garcia, Omaira; 24 Izaña Atmospheric Research Center AEMET Tenerife Spain
Röhling, Amelie N.; 25 Karlsruhe Institute of Technology IMK‐ASF Karlsruhe Germany
Schneider, Matthias; 25 Karlsruhe Institute of Technology IMK‐ASF Karlsruhe Germany
Blumenstock, Thomas; 25 Karlsruhe Institute of Technology IMK‐ASF Karlsruhe Germany
Tully, Matt; 26 Bureau of Meteorology Melbourne Australia
Paton‐Walsh, Clare; 27 Centre for Atmospheric Chemistry University of Wollongong Wollongong Australia
Jones, Nicholas; 27 Centre for Atmospheric Chemistry University of Wollongong Wollongong Australia
Querel, Richard; 28 National Institute of Water and Atmospheric Research Lauder New Zealand
Strahan, Susan; 29 NASA Goddard Space Flight Center Earth Sciences Division Greenbelt MD USA
Stauffer, Ryan M.; 29 NASA Goddard Space Flight Center Earth Sciences Division Greenbelt MD USA
Thompson, Anne M.; 29 NASA Goddard Space Flight Center Earth Sciences Division Greenbelt MD USA
Inness, Antje; 32 European Centre for Medium‐Range Weather Forecasts Reading UK
Engelen, Richard; 32 European Centre for Medium‐Range Weather Forecasts Reading UK
Chang, Kai‐Lan; 19 Cooperative Institute for Research in Environmental Sciences (CIRES) University of Colorado Boulder CO USA
Cooper, Owen R.; 19 Cooperative Institute for Research in Environmental Sciences (CIRES) University of Colorado Boulder CO USA
Abstract
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 2000–2020 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.
Plain Language Summary: Worldwide actions to contain the COVID‐19 virus have closed factories, grounded airplanes, and have generally reduced travel and transportation. Less fuel was burnt, and less exhaust was emitted into the atmosphere. Due to these measures, the concentration of nitrogen oxides and volatile organic compounds (VOCs) decreased in the atmosphere. These substances are important for photochemical production and destruction of ozone in the atmosphere. In clean or mildly polluted air, reducing nitrogen oxides and/or VOCs will reduce the photochemical production of ozone and result in less ozone. In heavily polluted air, in contrast, reducing nitrogen oxides can increase ozone concentrations, because less nitrogen oxide is available to destroy ozone. In this study, we use data from three types of ozone instruments, but mostly from ozonesondes on weather balloons. The sondes fly from the ground up to 30 kilometers altitude. In the first 8 km, we find significantly reduced ozone concentrations in the northern extratropics during spring and summer of 2020, less than in any other year since at least 2000. We suggest that reduced emissions due to the COVID‐19 crisis have lowered photochemical ozone production and have caused the observed ozone reductions in the troposphere.
Key Points:
In spring and summer 2020, stations in the northern extratropics report on average 7% (4 nmol/mol) less tropospheric ozone than normal
Such low tropospheric ozone, over several months, and at so many sites, has not been observed in any previous year since at least 2000
Most of the reduction in tropospheric ozone in 2020 is likely due to emissions reductions related to the COVID‐19 pandemic