Nitrogen dioxide decline and rebound observed by GOME-2 and TROPOMI during COVID-19 pandemic

Abstract:

Since its first confirmed case in December 2019, coronavirus disease 2019 (COVID-19) has become a worldwide pandemic with more than 16 million confirmed cases by July 2020. Countries and territories around the world have enforced lockdown measures to prevent the spread of the virus, introducing a temporal change of air pollutants strongly related to transportation, industry, and energy, such as nitrogen dioxide (NO₂).

In this contribution, the NO₂ variation over regions with strong social responses to COVID-19 is analyzed using the global long-term datasets from Global Ozone Monitoring Experiment-2 (GOME-2) sensor onboard the EUMETSAT Metop satellites and the high-resolution measurements from TROPOspheric Monitoring Instrument (TROPOMI) onboard the EU/ESA Sentinel-5 Precursor satellite. We briefly present the NO₂ retrieval algorithm for GOME-2 and TROPOMI developed at German Aerospace Center (DLR). We introduce the temporal and meteorological correction methods that statistically take into account the potential influences of long-term trend and short-term wind-driven transport, respectively. We present the decline and rebound of NO₂ concentration during and after the COVOD-19 lockdown for regions dominated by anthropogenic emissions in Asia, Europe, North and South America.