河南省2015-2019年大气污染时空变化特征研究

Spatial and temporal variation analysis of air pollution in Henan province during 2015—2019

河南省位于京津冀周边区域,其大气复合污染形势较为严峻.本研究利用河南省2015—2019年83个国控站点数据,综合探究了PM_(10)、PM_(2.5)、SO_(2)、NO_(2)、CO和O_(3)MAD8(臭氧日最大8 h平均值)的时空变化特征.与2015年相比,2019年河南省PM_(10)、PM_(2.5)、SO_(2)、NO_(2)和CO年均浓度分别下降了26.8%、26.5%、70.5%、17.1%和37.9%,而O_(3)MAD8的年均浓度却上升了19μg·m-^(3).从区域上看,除了O_(3)MAD8外,其它污染物的年均浓度最大值均出现在豫北地区,最低值出现在豫南地区.污染物季节变化特征较为明显,均呈现出冬季高、夏季低的特征(O_(3)MAD8除外),O_(3)MAD8则表现出相反的变化趋势.从日变化特征上看,PM_(10)、PM_(2.5)、SO_(2)、NO_(2)和CO呈“双峰”分布,最大值出现在8:00—11:00和22:00—0:00,而O_(3)的最大值出现在下午14:00—16:00,最小值出现在早上7:00左右.5个研究区域O_(3)与其他5种污染物呈现出明显的负相关,说明其他污染物的增加在一定程度上不利于O_(3)的生成.

Henan,located in the surrounding area of Beijing-Tianjin-Hebei,had been seriously affected by complex air pollution.This study systematically analyze the spatial and temporal variation of air pollutants(PM_(10)、PM_(2.5)、SO_(2)、NO_(2)、CO、O_(3)MAD8(O_(3)maximum daily 8 h average)),based on data from 83 national air quality monitoring sites in Henan province during 2015—2019.From 2015 to 2019,annual mean concentrations of PM_(10)、PM_(2.5)、SO_(2)、NO_(2)and CO decreased by 26.8%、26.5%、70.5%、17.1%and 37.9%,respectively.In contrast,concentration of O_(3)MAD8 increased 19μg·m^(-3).Except O_(3)MAD8,the annual mean concentration of all pollutants were the highest in North Henan and lowest in South Henan.In all regions of Henan,there were obvious season variations of the six pollutants.The concentrations were higher in winter than that in summer,except O_(3)MAD8,which exhibited an opposite seasonal variation pattern.Diurnal variations of six pollutants(except for O_(3))revealed a bimodal pattern with peaks between 8:00—11:00 and 22:00—0:00,whereas O_(3)concentration waxed between 14:00—16:00 and waned in 7:00.In all regions,negative correlation were found between O_(3)and the other pollutants,demonstrating that enhanced pollution by other pollutants is unfavorable to O_(3)formation.