Spatio-temporal variation of PM2.5 pollution in Xinjiang and its causes: The growing importance in air pollution situation in China

Due to the differences in topographic features, water vapor distribution and emission structures between north south of Xinjiang Uygur Autonomous Region (hereinafter Xinjiang), air pollution exhibits remarkable spatial heterogeneity this region. In study, is divided into four regions from at municipality scale based on data quality monitoring sites recorded 2013–2019, namely, clean area northern (region I), heavily polluted Urumqi-Changji-Shihezi region Ⅲ), moderately southern Ⅱ), severely Ⅳ). For highly Xinjiang, Ⅲ Ⅳ are compared with those typical central eastern China, spatio-temporal variation characteristics causes PM 2.5 each sub-region discussed. The results show that a anthropogenic source, where occurrence frequency intensity moderate level or above (18%) higher than most China (16%, North west Huang-Huai). IV affected by dust weather, being about 52% much other regions. addition, under combined effects sources aerosols, duration II prolonged. Therefore, contrast improvement has become relatively more severe recent years. Moreover, as upstream mid-latitude westerlies, heavy due sand dust, their mixing far-reaching impact downstream areas, further highlighting growing importance prevention control Xinjiang.