[Analysis of Air Pollution Characteristics and Meteorological Conditions in Zhengzhou from 2014 to 2017].

Online monitoring data of atmospheric pollutants and meteorological parameters in Zhengzhou from 2014 to 2017 were collected to analyze the concentration levels, seasonal variations, and the ratio characteristics of atmospheric pollutants, as well as the effects of meteorological conditions on these pollutants. Results show that the annual average concentrations of PM _2.5 and PM ₁₀ in the four years were (88±49.8), (95.8±60.2), (78.6±70.3), and (72.0±53.5) μg·m ^-3 , and (158.5±65.3), (167.7±82.6), (144.5±91.5), and (132.7±70.3) μg·m ^-3 , respectively, and were approximately two times higher than the grade Ⅱ annual limits set by China. Fuel combustion and the formation of secondary pollutants were the main sources of PM _2.5 in Zhengzhou. Moreover, the contribution of coal combustion was found to be decreased, while that of traffic sources increased year by year. Low wind speed, high humidity, and reduced precipitation are important meteorological factors that contribute to serious air pollution. In addition, the Potential Source Contribution Function and the Concentration-Weighted Trajectory were used to analyze the potential sources, and the contribution of these sources to the distribution of PM _2.5 . The potential source areas of PM _2.5 were mainly distributed in neighboring cities and provinces, such as Shanxi, Shaanxi, Hubei, Shandong, and Hebei. The short-distance transmission was found to contribute significantly to the mass concentration of PM _2.5 .