Document Type : Original Article


NUIST Reading Academy, 219 Ningliu Road, Nanjing, Jiangsu, 210044, P.R. China


The COVID-19 pandemic, which began during early 2020, had been a worldwide problem, resulting in significant fatalities. In China, the pandemic resulted in strict lockdowns, restricted movement, and reduced transportation. This resulted in improvement of air quality in many cities in China. The objective of the study is to compare the nature of air quality pre-COVID period (2018-2019) and during COVID period (2020-2201). The following air quality parameters were investigated, air quality index (AQI), particulate matter (PM2.5 and PM10), sulphur dioxide (SO2), nitrogen dioxide (NO2), ozone (O3), and carbon monoxide (CO). The present investigation results will augment to the current understanding on the air pollution situation during the COVID-19 pandemic in Jiangsu Province in China. The study revealed that air quality in Jiangsu Province improved during the months when COVID-19 positive cases increased. The reduction in air pollutants concentrations started during 2020 and reached a maximum during 2021. Overall the air quality index (AQI) improved by 8.2 % and air pollutant reductions achieved were, PMs (≈ 21%), SO2 (26.2 %), NO2 (13.6 %), O3 (2.4 %) and CO (10.4 %). Cities in Jiangsu Province with high air pollutant concentrations achieved a moderate reduction. The correlation between air pollutants and AQI was positive except for O3. The implications of the study are, reduction of fossil fuel powered vehicles and industrial activity can make notable positive impact on the air quality of the region.


Main Subjects

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