Global, continental, and national variation in PM_2.5, O₃, and NO₂ concentrations during the early 2020 COVID-19 lockdown.

ABSTRACT: Lockdowns implemented in response to COVID-19 have caused an unprecedented reduction in global economic and transport activity. In this study, variation in the concentration of health-threatening air pollutants (PM_2.5, NO₂, and O₃) pre- and post-lockdown was investigated at global, continental, and national scales. We analyzed ground-based data from >10,000 monitoring stations in 380 cities across the globe. Global-scale results during lockdown (March to May 2020) showed that concentrations of PM_2.5 and NO₂ decreased by 16.1% and 45.8%, respectively, compared to the baseline period (2015-2019). However, O₃ concentration increased by 5.4%. At the continental scale, concentrations of PM_2.5 and NO₂ substan

SUBMITTER: He C 

PROVIDER: S-EPMC7867708 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature