Analysis of changes and trends in ambient air pollutant concentrations in the Beijing-Tianjin-Hebei region in recent years

Abstract

The Beijing-Tianjin-Hebei region is a key prevention and control area for air pollution in China. Based on the PM2.5, PM10, SO2, NO2 and AQI data published by the Ministry of Ecology and Environment and the online monitoring and analysis platform of air quality, the temporal variation of air pollutant concentrations in the Beijing-Tianjin-Hebei region from 2019 to 2021 and the contribution of each pollutant to air pollution were analyzed by the comprehensive pollution index method and the pollution load factor method. The results show that: (1) The changes in the comprehensive air pollution index and AQI index in the Beijing-Tianjin-Hebei region from 2019 to 2021 show a downward trend. Compared with the annual average concentrations of PM2.5, PM10, SO2 and NO2 in 2019, the average concentrations of PM2.5, PM10, SO2 and NO2 decreased by 23.72%, 19.28%, 34.28% and 24.03%, respectively. (2) The monthly average change of the concentration of various pollutants in the Beijing-Tianjin-Hebei region from 2019 to 2021 shows a roughly shaped “U”, following the governing rule of "high in winter and low in summer, rising in autumn and falling in spring". (3) The average pollution load coefficients of four pollutants in the Beijing-Tianjin-Hebei region, including PM2.5, PM10, SO2 and NO2, were 38.18%, 31.64%, 3.84% and 26.34% from 2019 to 2021, respectively. It indicates that the ambient air quality in this area is greatly affected by particulate matter pollution.