摘要
基于2015-2020年成都市国控环境监测站点逐时大气污染物监测数据,将其分为3类站点(城区、交通、背景站点),研究不同季节、不同污染水平下,各类站点细颗粒物(PM_(2.5))和臭氧(O_(3))复合污染特征及相互作用.结果表明:(1)成都各类站点的PM_(2.5)超标天数和PM_(2.5)年平均浓度总体呈下降趋势,背景站点浓度明显小于城区站点和交通站点;O_(3)年际变化趋势呈波动性,且交通站点和背景站点的变化波动强于城区站点.(2)各类站点PM与O_(3)相关性在O_(3)污染期(4-8月)和PM污染期(11-次年1月)均存在显著差异,且二者在不同季节甚至呈现相反的相关性,总体趋势为夏季PM_(2.5)-O_(3)的相关性趋于正相关,冬季趋于负相关.(3)O_(3)污染期,各类站点二次PM的浓度和贡献率随光化学水平的升高而增加,而一次PM_(2.5)日变化幅度差异不大,表现出明显的O_(3)和PM_(2.5)协同增长现象.(4)PM_(2.5)污染期,PM_(2.5)与O_(3)之间并不是简单的线性关系,不同PM_(2.5)污染程度下,各类站点O_(3)浓度变化率昼夜波动趋势基本相同,均在12:00-13:00达到峰值,在18:00达到谷值;且随着PM_(2.5)浓度的增加,O_(3)浓度变化率峰值/谷值波动范围亦随之增加.
The characteristics and interaction between fine particulate matter(PM_(2.5))and ozone(O_(3))combined pollution in different types of sites(classified as urban site,traffic site,background site)under different seasons and pollution levels in Chengdu has been studied,by using the hourly air pollution monitoring data from the national-controlled environmental monitoring sites from 2015 to 2020.Results showed that:①The number of days with PM_(2.5)-exceedance and the annual mean PM_(2.5) concentration in all types of sites showed a general downward trend.And the PM_(2.5) concentration of background site was significantly lower than that of urban site and traffic site.The interannual variation trend of O_(3) was fluctuating,and the fluctuation of traffic site and background site was stronger than that of urban site.②Whether during O_(3) pollution season(April to August)or PM_(2.5) pollution season(November to January of next year),the correlation between PM_(2.5) and O_(3) varied significantly among different types of sites(They even showed opposite correlation during different seasons).The overall trend was that the relationship of PM_(2.5)-O_(3) tended to be positive in summer and negative in winter.③During O_(3) pollution season,with the increase of photochemical level,the concentration and contribution of secondary PM_(2.5) increased accordingly,while the difference of daily variation of primary PM_(2.5) at various sites was not significant,which showed obvious synergistic growth of O_(3) and PM_(2.5).④During PM_(2.5) pollution season,the relationship between PM_(2.5) and O_(3) was not merely a linear.The diurnal variation of O_(3) concentration change rate at various sites under different PM_(2.5) pollution levels tended to be consistent,all reached a peak at 12:00-13:00 and a trough at 18:00.In addition,with the increase of PM_(2.5) concentration,the range of peak/trough fluctuations of O_(3) concentration change rate increased as well.
作者
康平
侯静雯
冯浩鹏
张小玲
曾胜兰
郑国伟
KANG Ping;HOU Jingwen;FENG Haopeng;ZHANG Xiaoling;ZENG Shenglan;ZHENG Guowei(Plateau Atmosphere and Environment Key Laboratory of Sichuan Province,School of Atmospheric Sciences,Chengdu University of Information Technology,Chengdu 610225;Chengdu Plain Urban Meteorology and Environment Observation and Research Station of Sichuan Province,Chengdu 610225)
出处
《环境科学学报》
CAS
CSCD
北大核心
2022年第10期80-90,共11页
Acta Scientiae Circumstantiae
基金
国家重点研发计划(No.2018YFC0214001)
国家外国专家项目(No.G2021036001)
成都市重大科技应用示范项目(No.2020-YF09-00031-SN)。
关键词
细颗粒物
臭氧
复合污染
污染相互作用
成都市
fine particulate matter
ozone
combined pollution
pollution interactions
Chengdu
