一次强沙尘过程对江苏省空气质量的影响研究

Study on Air Quality Impacted by a Strong Sand-Dust Process in Jiangsu Province

2021年3月15—17日,江苏省自北向南经历了一次严重沙尘污染过程,在此期间对连云港和苏州2市的PM_(10)和PM_( 2.5)质量浓度,以及退偏振比参数进行连续观测,结合后向轨迹(HYSPLIT)模型对沙尘气团来向进行分析。结果表明,本次沙尘过程起源于蒙古国南部,起沙之后自西北至东南传输,约24 h后开始影响江苏省。受其影响,江苏省3月16日4市达重度污染,沙尘对苏北和苏南城市影响差异较大,连云港市PM_(10)质量浓度短时高达978μg/m^( 3),近地面至高空2 km退偏振比值达0.3左右,沙尘特征较明显;苏州市受沙尘影响时间较连云港滞后约14 h,PM_(10)质量浓度峰值仅为155μg/m ^(3),以浮尘天气为主。

From 15 to 17 of March 2021,Jiangsu was sufferring a severe air pollution impacted by a sand-dust storm.The concentration of PM_(10)and PM_(2.5),the depolarization ratio of particulate matter,and the backward trajectory by HYSPLIT were analyzed.The results showed that the air pollution process was a typical sand-dust transportation from the northwest to the southeast,which originated in southern Mongolia and began to affect Jiangsu Province 24 hours later.On March 16,the air quality of 4 cities in Jiangsu have reached heavy pollution.There were significant differences in the impact of sand-dust on the southern and northern regions of Jiangsu.The characteristics of sand-dust pollution in Lianyungang in northern Jiangsu were more obvious,with a peak hourly PM_(10)concentration of 978μg/m^(3).The aerosol depolarization ratio in Lianyungang was about 0.3 from near the ground to 2 km altitude.The sand-dust pollution in Suzhou was 14 hours later than that in Lianyungang,and the pollution level had been reduced to floating dust,with the PM_(10) peak value 155μg/m^(3).