Environmental injustices associated with coronavirus-related changes in NO2 pollution

Abstract:

A purported side effect of the coronavirus pandemic is reduced anthropogenic air pollution emissions due to the lockdowns imposed on many cities around the world. In this study, we investigate the impact of the lockdowns on total column nitrogen dioxide (NO₂) in the contiguous United States (U.S.) using satellite retrievals from the TROPOspheric Monitoring Instrument (TROPOMI) for a period prior to lockdowns and during the lockdown period. While NO₂ decreases on average across the U.S., the magnitude of the decrease varies considerably, and some areas experience increases. The unprecedented spatial resolution of the TROPOMI retrievals together with census tract-level data (e.g., income, race, educational attainment) allow us to peer into individual neighborhoods and (1) establish which groups bear disproportionate exposure to NO₂ prior to lockdowns and (2) document which populations experience the largest and smallest gains in lockdown-related changes in NO₂. We also tie these findings to changes in human mobility characterized by traffic data. Our findings build on past studies that have documented disparities in air pollution exposure and associated health risks but provide new insights achieved by leveraging the dramatic changes in human behavior that are unique to the pandemic-related lockdowns and high resolution TROPOMI NO₂ observations. Results may be useful for future development of environmental policies aimed at reducing air pollution and minimizing health disparities.