NO2 pollution decrease in big cities of Latin America during COVID-19 pandemic

Abstract

NO2 is a mainly anthropogenic gas that affects population health and its exposure is associated with several respiratory diseases. Its tropospheric concentration is associated with vehicle emissions. During 2020, COVID-19 lockdowns have impeded population's mobility, hence constructing an almost ideal situation to study their relationship with tropospheric NO2 concentration. We used TROPOMI satellite images, Google mobility reports and vehicule count in order to study these relationships in six big Latin American metropolitan areas. In all of them, tropospheric NO2 concentration decreased during 2020 compared to 2019, particularly during April 2020. The daily vehicle count in Buenos Aires was a significantly important variable in order to explain NO2 concentration variations. This study strengthens previous research findings about NO2 concentration reduction during COVID-19 lockdowns and shows the relationship between human mobility and air pollution in the particular context of Latin America big cities.