2015-2021年河南省PM_(2.5)-O_(3)复合污染时空特征分析

Spatiotemporal Distribution Characteristics of Co-pollution of PM_(2.5)-O_(3) in Henan Province From 2015 to 2021

基于2015—2021年河南省17个城市的污染和气象数据,分析了河南省PM_(2.5)-O_(3)复合污染的时空分布特征及与气象条件的关系。结果表明:2015—2021年河南省PM_(2.5)-O_(3)复合污染累计出现8~60 d,平顶山、焦作、郑州、新乡和安阳出现次数较多,周口、三门峡、信阳、鹤壁和南阳出现较少。PM_(2.5)-O_(3)复合污染主要出现在4—10月。PM_(2.5)与O_(3)呈现“夏正冬负”的相关性,在春季和秋季呈弱相关。PM_(2.5)污染等级为优时,与O_(3)呈正相关;而其它PM_(2.5)污染等级时,与O_(3)为负相关。河南省PM_(2.5)-O_(3)复合污染出现时的主要温度区间为20.1~25.8℃,相对湿度(RH)区间为54.0%~69.0%,风速区间为1.3~2.5 m/s,风向为NE—E和SSE—SSW。郑州市南部周边城市的污染传输对其PM_(2.5)-O_(3)复合污染有重要贡献。

Based on the pollutants and meteorological factors observed data of 17 cities in Henan province from 2015 to 2021,the spatiotemporal distribution characteristics of PM_(2.5)-O_(3) co-pollution and the relationship with meteorological conditions in Henan province were analyzed.The results revealed that the PM_(2.5)-O_(3) co-pollution in Henan province accumulated for 8~60 d from 2015 to 2021,with more occurrences in Pingdingshan,Jiaozuo,Zhengzhou,Xinxiang and Anyang,and fewer occurrences in Zhoukou,Sanmenxia,Xinyang,Hebi and Nanyang.The PM_(2.5)-O_(3) co-pollution mainly occurred from April to October.O_(3) was positively correlated with PM_(2.5) in summer and negatively correlated in winter.A weak correlation in spring and fall was found.When the PM_(2.5) pollution level was excellent,PM_(2.5) was positively correlated with O_(3),and other PM_(2.5) pollution levels were negatively correlated.The main temperature intervals at the time of PM_(2.5)-O_(3) co-pollution in Henan province were 20.1~25.8℃,the relative humidity(RH)intervals were 54.0%~69.0%,the wind speed intervals were 1.3~2.5 m/s,and the wind directions were NE—E and SSE—SSW.Pollution transmission in the southern surrounding cities of Zhengzhou has made an important contribution to its PM_(2.5)-O_(3) co-pollution.