Effect of Reduced Emissions from Thermal Power Plants in China on Local Air Quality Improvement

In September 2021, China encountered the shortage of coal and emission activity shrunk to the lowest it had been since February 2020, when coronavirus lockdowns paralyzed the economy. Despite social and economic concerns, this event has brought unexpected positive consequences for environmental quality. In this study, we investigated the impact of restricted thermal power plants operations on local air quality is investigated. For this purpose, social statistics, satellite observations, ground-based air quality measurements, and meteorology data were analyzed to estimate the spatio-temporal characteristics of air pollutants. As a result, significant reductions in the concentrations of air pollutants were found. It was about 11.13% lower than the reduced concentration due to the coronavirus lockdowns period in China. Compared to the average value during the normal year for 2015-2019, large decreased values of SO2 (-38.81%), CO (-24.78%), NO2 (-54.26%), PM 10 (-51.60%), and PM2.5 (-56.35%) were measured in Seoul, Korea. Satellite observation data confirm that these large drop in air pollution levels occurred in both countries, serving as a valuable proof of the emission control impact on local air quality. Moreover, the easterly wind along with the increased precipitation rate in China could affect the wet deposition and dilution of air pollutants.