Impact of COVID-19 on air quality in the Yangtze River Delta, China.

ABSTRACT: To investigate the effect of nationwide restrictions due to COVID-19 on air quality in the Yangtze River Delta (YRD), China, we defined four periods named period I (January 1 to 23, 2020), period II (January 24 to February 23), period III (February 24 to April 7), and period IV (April 8 to May 31), which indicated normal period, lockdown period, regional work resumption period, and nationwide work resumption period, respectively. Hourly PM_2.5, PM₁₀, NO₂, SO₂, CO, and O₃ in 41 cities in the YRD region were analyzed. Compared to period I, NO₂ decreased by 58% during period II and increased in periods III and IV. SO₂ remained constant during the four periods (7-8 μg/m³). Higher PM_2.5 concentrati

SUBMITTER: Yao L 

PROVIDER: S-EPMC8315727 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature