石家庄市2020年秋冬季首轮灰霾污染过程分析

Analysis of the first haze pollution episode in fall and winterof 2020 in Shijiazhuang

为了探究石家庄市秋冬季重污染天气成因,采用石家庄市大气复合污染及灰霾监测超级站监测数据,结合地面空气站实况监测数据及气象资料,对2020年10月8日—11日石家庄市入秋后首轮灰霾污染过程进行分析,并探析污染物的组成及灰霾成因。结果表明:1)在此次污染过程期间,地面湿度较大且处于高压后部的辐合区,污染物形成堆积;2)根据组分重构污染特征分析可知,灰霾过程中NO_(x)向硝酸根离子的转化驱动了PM_(2.5)不断攀升,日均浓度达到中度污染水平;3)与2019年入秋后首次污染过程相比,2020年入秋后首次污染过程移动源占比显著增加,呈现明显的机动车源特征。研究结果能够为石家庄市进一步加强机动车源管控提供依据,调整交通运输结构、提高交通管理水平提供依据,并可为城市环境精细化管理提供技术参考。

In order to explore the cause of pollution in fall and winter of Shijiazhuang,the pollution process of the first haze pollution episode in fall in Shijiazhuang from October 8th to 11th,2020 was analyzed by using the monitoring data of combined air pollution and haze from super station,combining with monitoring data and meteorological data of ground air station,and the composition of polluants and the causes of haze were explored too.The results show that:1)during the process of the pollution,with high ground humidity,the pollutants are accumulated in the convergence zone of the back of high pressure;2)based on the analysis of component reconstruction and pollution characteristics,the concentration of PM_(2.5)increases due to the conversion of NOx into nitrate,the average daily concentration reaches medium pollution level;3)compared with the first pollution episode in fall 2019,the proportion of motor vehicle sources increases significantly in the first pollution episode in fall 2020,which presents obvious characteristics of motor vehicle source.The research results can strengthen the management of motor vehicle source,readjust the transportation structure and improve the management level of transportation,provide technical reference for the delicacy management of city envionment.