Changes in physical and chemical properties of urban atmospheric aerosols and ozone during the COVID-19 lockdown in a semi-arid region.

ABSTRACT: The synergistic response of urban atmospheric aerosols and ozone (O₃) to reduction of anthropogenic emissions is complicated and still needs further study. Thus, the changes in physical and chemical properties of urban atmospheric aerosols and O₃ during the Coronavirus Disease 2019 (COVID-19) lockdown were investigated at three urban sites and one rural site in Lanzhou with semi-arid climate. Fine particulate matter (PM_2.5) decreased at four sites by ∼ 20% while O₃ increased by >100% at two urban sites during the COVID-19 lockdown. Both primary emissions and secondary formation of PM_2.5 decreased during the lockdown. Significant increase in both sulfur and nitrogen oxidation ratios was found in the afternoon, which accounted for 48.7%

SUBMITTER: Chang Y 

PROVIDER: S-EPMC9259058 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature