资源环境科技发展态势分析平台

The Copernicus Atmosphere Monitoring Service (CAMS) has contributed to the newly-released study led by the German Meteorological Service Deutscher Wetterdienst. The study sheds light on highly unusual low ozone values in the free troposphere in the Northern Hemisphere and suggests that reduced emission due to COVID-19 restrictions have caused ozone reductions between 1 and 8 kilometres altitude. CAMS is implemented by the European Centre for Medium-Range Weather Forecasts on behalf of the European Commission.

Richard Engelen, Deputy Director of the Copernicus Atmosphere Monitoring Service, comments: “The COVID-19 pandemic led to lockdown measures around the globe, which had a significant effect on our emissions. For example, less transport and aviation meant less fuel was burnt and less emission were released into the atmosphere. This caused lower concentration of nitrogen oxides, which are main drivers for photochemical reactions in the atmosphere. Low concentrations of nitrogen oxides in the free troposphere meant low photochemical production, which resulted in less ozone.”

“Our CAMS reanalysis data contributed to the study by showing that the low ozone values, as observed by the balloon sonde observations, could not be explained by year-to-year changes in the meteorological conditions, which led to the conclusion that reduced emissions are likely the main cause”, he adds.

Whereas in the stratosphere ozone plays a key role to protect life on the Earth’s surface from harmful and dangerous UV-radiation, ozone in the troposphere is a pollutant as well as a major greenhouse gas. Ideally, there should be a lot of ozone in the stratosphere, and just a little in the troposphere. Human activities, however, have resulted in a decrease of stratospheric ozone over the last century, and in increases of tropospheric ozone.

You can access the DWD press release here: https://www.dwd.de/presse

You can access the study by DWD here: https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020GL091987

CAMS microsite with information air quality in support of the COVID-19 crisis: https://atmosphere.copernicus.eu/european-air-quality-information-support-covid-19-crisis

* This image has been corrected since the Press Statement was sent out.