嘉峪关市大气污染物传输特征与潜在源分析

ANALYSIS OF TRANSMISSION CHARACTERISTICS AND POTENTIAL SOURCES OF AIR POLLUTANTS IN JIAYUGUAN

利用Meteoinfo软件中的Trajstat插件对2019-03—2020-02期间抵达嘉峪关市的气团进行后向轨迹模拟,并结合各类大气污染物数据,对嘉峪关市四季的后向轨迹进行聚类分析,研究抵达嘉峪关市的主要气团输送路径及对应路径的污染物浓度特征。通过潜在源贡献因子法(PSCF)及权重浓度轨迹分析法(CWT)来分析PM_(10)与O;的输送来源及主要潜在源区。结果表明:输送至嘉峪关市的气团中,西北方向气团轨迹数目和污染轨迹数目占比均大于其余方向,嘉峪关市四季的大气污染更易受到西北方向气团的影响。嘉峪关市春季PM_(10)污染相对严重,更易受到新疆东部地区潜在源区的影响,其余三季PM_(10)污染相对较轻,潜在源区主要集中在新疆东部地区,少数位于嘉峪关市东北方向。嘉峪关市春、夏季的O;污染相对严重,强潜在源区主要集中在新疆东部地区及甘肃河西走廊地区,秋、冬季O;污染相对较轻,其中秋季潜在源区主要位于甘肃河西走廊地区,冬季潜在源区主要位于新疆东部地区。

Use the Trajstat plug-in in the Meteoinfo software to simulate the backward trajectory of the air masses arriving in Jiayuguan City from March 2019 to February 2020,and combine the data of various air pollutants to perform a cluster analysis of the backward trajectory of Jiayuguan City in the four seasons.In this way,we studied the main air masses transportation path and the pollutant concentration characteristics of the corresponding path to Jiayuguan City.The potential source contribution function(PSCF)and concentration weighted trajectory(CWT)were used to analyze the impact of pollutant transportation sources and main potential source areas and the transmission of air pollutants on air quality in Jiayuguan City.Among the air masses transported into Jiayuguan City,the number of air mass trajectories in the northwest and the percentage of pollution trajectories were larger than those in the other directions.The air pollution in Jiayuguan City in four seasons was more susceptible to the influence of air masses in the northwest.Jiayuguan City had relatively serious PM_(10) pollution in spring and was more susceptible to potential source areas in eastern Xinjiang,and PM_(10) pollution in other seasons was relatively light.The potential source areas were mainly concentrated in eastern Xinjiang,with a few located in the northeast of Jiayuguan City.The O;pollution in Jiayuguan City in spring and summer was relatively serious.The strong potential source areas were mainly concentrated in eastern Xinjiang and the Hexi Corridor area of Gansu.The O;pollution in autumn and winter was relatively light.The potential source area in autumn was mainly located in the Hexi Corridor area of Gansu,and the potential source area in winter was mainly located in eastern Xinjiang.