基于大气成分观测网的山西省近地面O3体积分数分布特征  

Distribution Characteristics of Near Surface Ozone Volume Fraction in Shanxi Province Based on Atmospheric Composition Observation Network

作　　者：李莹 王淑敏 裴坤宁 闫世明 孙鸿娉 张逢生 高兴艾 LI Ying;WANG Shu-min;PEI Kun-ning;YAN Shi-ming;SUN Hong-ping;ZHANG Feng-sheng;GAO Xing-ai(Shanxi Branch of Monitoring and Assessment Center for GHGs&Carbon Neutrality,China Meteorological Administration,Shanxi Institute of Meteorological Sciences,Taiyuan 030006,China;Shanxi Weather Modification and Lightning Protection Technical Center,Taiyuan 030006,China)

机构地区：[1]山西省气象科学研究所,中国气象局温室气体及碳中和监测评估中心山西分中心,太原030006 [2]山西省人工增雨防雷技术中心,太原030006

出　　处：《环境科学》2024年第2期655-667,共13页Environmental Science

基　　金：山西省基础研究计划青年科学研究项目(20210302124617,202203021212112);山西省气象局项目(SXKMSDW20217114)。

摘　　要：利用山西省6个大气成分观测站2019年3月至2020年2月的反应性气体O_(3)、NO、NO_(2)和NO_(x)连续观测资料以及同期气象资料,采用统计分析和后向轨迹分析等方法,对山西近地面O_(3)体积分数变化特征及影响因素进行了对比研究.结果表明,6个站的O_(3)体积分数一般在4~9月较高,10月至翌年3月较低,研究期内山西南部的晋城和临汾2站的O_(3)日最大8h体积分数滑动平均值φ(MDA8O_(3))超标最严重,其次是北部的五台山、朔州和大同3站,中部的太原站O_(3)污染较轻.对比城市站和高山站发现,两类站点的O_(3)体积分数季节变化虽都表现为:夏季>春季>秋季>冬季,但前者主要受前体物NO_(x)光化学反应的影响,后者的NO_(x)并不是产生高体积分数O_(3)的主要来源;两类站点的O_(3)日变化谱型截然相反,城市站O_(3)小时平均体积分数的峰谷值分别出现在15:00和06:00,而高山站分别出现在20:00和10:00,分别比城市站滞后了约5 h;此外城市站的O_(3)日振幅明显大于高山站.就城市站而言,相较日照时数、降水量和总云量,气温对O_(3)体积分数的影响更为显著;白天的NO_(2)体积分数直接影响O_(3)的日振幅大小,尽管太原站O_(3)的光化学生成潜力也较高,由于被高体积分数的NO滴定消耗,O_(3)体积分数为城市站中最低;各城市站高体积分数的O_(3)对应低体积分数的NO_(x),低NO_(x)以NO_(2)为主,高NO_(x)的贡献则主要来自NO,在较高NO_(x)体积分数时,O_(3)基本上完全被消耗.影响全部站点O_(3)体积分数升高的地面风主要来自东南、南和西南方向,特定的风速条件将导致站点O_(3)体积分数增加.站点地理位置不同会引起大气污染物输送作用的差异,而来自华北平原和汾渭平原高浓度O_(3)的水平输送很可能是造成山西各站点O_(3)体积分数升高的共同原因.Based on the continuous data of O_(3),NO,NO_(2),and NO_(x) and the meteorological data from March 2019 to February 2020 at six atmospheric composition observation stations in Shanxi Province,the characteristics and influence factors of O_(3) volume fractions were studied using statistical analysis and backward trajectory analysis.The results showed that O_(3) volume fractions were generally higher from April to September and lower from October to the following March.During the study period,O_(3) pollution represented by φ(MDA8O_(3)),i.e.,the maximum daily 8-h average of O_(3) volume fractions,was the most serious at the Jincheng and Linfen stations in the south of Shanxi,followed by that in the Wutaishan,Shuozhou,and Datong stations in the north,with the least pollution occurring at the Taiyuan station in the middle.There were differences between the urban and alpine stations,although their seasonal O_(3) volume fractions were both summer>spring>autumn>winter.O_(3) volume fractions at the urban station were usually lower than those at the alpine station;O_(3) at the urban station might have been influenced by photochemical reactions with precursor NO_(x);however,this was not the main source of high O_(3) at the alpine station.The peak and valley values appeared at 15:00 and 06:00,respectively,at the urban station,whereas they appeared at 20:00 and 10:00,respectively,at the alpine station,representing diametrically opposite diurnal variation patterns.Further,the daily amplitude of O_(3) at the urban station was much larger than that at the alpine station.For urban stations specifically,temperature was the most important meteorological factor affecting O_(3) volume fraction,compared with sunlight hours,precipitation,and total cloud cover.The NO_(2) volume fraction in the daytime affected the daily amplitude of O_(3);although the photochemical generation potential of O_(3) at the Taiyuan station was good,the O_(3) volume fractions were the lowest among urban stations due to strong NO titration.The higher O_(3) corr

关 键 词：O_(3)体积分数 前体物NO_(x) 城市站 高山站 气团输送 

分 类 号：X515[环境科学与工程—环境工程]