Study on Spatial-temporal Variation of Atmospheric Pollution in China between 2014 and 2019

The study in this paper reveals that the atmospheric contaminants in mainland China is of concentricity in spatial distribution, persistence in temporal distribution and correlation between different parameters. This spatial-temporal variation law plays an important role in improving and addressing the problem with atmospheric environment of given cities and regions by employing focused and pointed measures. In this paper, seven kinds of atmospheric pollution parameters including PM2.5, PM10, AQI, CO, NO2, O3 and SO2 in 370 Chinese cities from 2014 to 2019 are analyzed based on their hourly mass concentration. The spatial-temporal variations of each parameter in each separated year are obtained by using interpolation calculation towards the annual atmospheric pollution parameters. The results show that higher mass concentration (including the highest mass concentration) of PM2.5, AQI, PM10, CO, NO2, SO2 mainly concentrated in Beijing-Tianjin-Hebei region in the northeast of mainland China and its neighboring regions and Xinjiang region in the northwest of mainland China. The spatial variation of PM2.5, AQI, PM10, CO, NO2, SO2 experienced similar trend. Higher mass concentration (including the highest mass concentration) of O3 mainly concentrated in Qinghai and Inner Mongolia in the central north of mainland China and Shandong on the right side of Beijing-Tianjin-Hebei region. The spatial variation of O3 experienced different trend from that of other parameters. PM2.5, AQI, PM10 indicated increase and decrease, followed by increase and decrease again with time, which was a S-shaped change. Almost the same temporal variation happened to PM2.5, AQI, PM10 and to CO, NO2, SO2, which was opposite to O3. The analysis from the perspective of the annual highest mass concentration of PM2.5, AQI, PM10, NO2 and O3 indicates the atmospheric environment of mainland China had not been authentically improved by 2019. The analysis from the perspective of the annual highest mass concentration of CO and SO2 indicates the atmospheric environment of mainland China had been authentically improved by 2019. What should we do immediately is to strengthen environmental governance and address the source of contamination in Beijing-Tianjin-Hebei region in the northeast of China, Xinjiang region in the northwest of China, Qinghai and Inner Mongolia regions in the central north of China.