摘要：利用多种地面观测资料,研究2011年4月14—15日上海的一次典型污染过程,分析生消机制、污染物来源以及气溶胶垂直分布的演变过程。结果表明,14、15日PM_2.5的日平均质量浓度分别为78.9、115.9μg/m³,均超过环境空气质量标准中PM_2.5质量浓度的二级标准;污染过程形成于稳定天气形势下污染物的积累,结束于短时降水和冷空气南下的共同作用;污染物主要源于上海本地及其西南方的局地污染;污染天气对流层低层的消光系数远大于非污染天气的。

关键词：大气污染；气溶胶；垂直分布；消光系数

Abstract：A typical air pollution process in Shanghai from April 14 to 15,2011 was investigated by a variety of observational data.The development mechanism,pollutant source and evolution process of aerosol vertical distribution were analyzed.The results show that the daily concentrations of PM_2.5 on April 14,15 are 78.9 and 115.9 μg/m³,respectively.This pollution period has an air quality grade worse than the Chinese air quality standard II of PM2.5.The pollution process is formed by pollutants accumulation due to stable synoptic situation and ended by short-term precipitation and cold air from the northwest.Pollutants come from local and southwest Shanghai.Vertical distribution of aerosol extinction coefficient in boundary layer in pollution period is much larger than that in non-pollution period.

Keywords：air pollution;aerosol;vertical distribution;extinction coefficient