一次长三角大气重污染期间浙江典型城市大气PM2.5污染成因分析  

The causes of PM2.5 pollution in typical cities of Zhejiang during a severe pollution event of Yangtze River Delta

作　　者：王琼真[1] 于燕 孟伟江 蒋琦清 张天[4] 晁娜[1] 吴电[1] 吴建[1] WANG Qiongzhen;YU Yan;MENG Weijiang;JIANG Qiqing;ZHANG Tian;CHAO Na;WU Dian;WU Jian(Environmental Science Research&Design Institute of Zhejiang Province,Hangzhou Zhejiang 310007;Zhejiang Institute of Meteorological Sciences,Hangzhou Zhejiang 310008;Times Shenghua Technology Co.,Ltd.,Hangzhou Zhejiang 311202;Hangzhou Environmental Monitoring Centre Station,Hangzhou Zhejiang 310007)

机构地区：[1]浙江省环境保护科学设计研究院,浙江杭州310007 [2]浙江省气象科学研究所,浙江杭州310008 [3]时代盛华科技有限公司,浙江杭州311202 [4]杭州市环境监测中心站,浙江杭州310007

出　　处：《环境污染与防治》2019年第9期1076-1081,共6页Environmental Pollution & Control

基　　金：国家重点研发计划项目(No.2018YFC0213806)

摘　　要：浙江大气PM 2.5污染问题突出。利用国家环境空气质量监测站的实时在线监测数据分析了2013年12月上旬长三角地区一次大气PM 2.5严重污染前后浙江典型城市(杭州、湖州、金华、宁波和舟山)的PM 2.5污染成因。结果表明,严重污染天(SPD)风速和大气边界层高度均较非污染天低,不利于污染物扩散,而气温和相对湿度高,易于二次颗粒物生成。PM 2.5/CO(质量比)的变化结果显示,SPD二次颗粒物对杭州、宁波、舟山PM 2.5浓度的贡献高于60%,对湖州和金华PM 2.5浓度的贡献略低(42%~54%)。杭州SPD时二次NO^-3、SO ^2-4、NH^+4的增长幅度远高于PM 2.5,且氮转化率和硫转化率随相对湿度的升高而上升,表明硫酸盐和硝酸盐的生成是PM 2.5污染的重要来源。气团后向轨迹显示,SPD时杭州和湖州主要受江苏、安徽及浙江省内其他城市气团传输的影响,宁波和舟山主要受上海、江苏、安徽及东海上空气团传输的影响,而金华主要受本地及邻近的杭州、绍兴的影响。Atmospheric PM 2.5 pollution is a serious issue in Zhejiang.In this study,the causes of PM 2.5 pollution in five typical cities indcluding Hangzhou,Huzhou,Jinhua,Ningbo and Zhoushan were comparatively analyzed during a severe PM 2.5 pollution event of Yangtze River Delta in early December,2013,based on real time on-line observation data from nation-controlled stations.Results showed that wind speed and height of planetary boundary layer decreased in severe pollution days(SPD)in all the five cities,leading to accumulations of atmospheric pollutants,while temperature and relative humidity increased,easy to formaiton of secondary particles.Based on the variation of PM 2.5/CO(mass ratio),secondary particles were estimated to account for more than 60%of PM 2.5 in Hangzhou,Ningbo and Zhoushan,while only 42%-54%in Huzhou and Jinhua.In Hangzhou,the increase of secondary NO^-3,SO 2^-4 and NH^+4 in SPD was significantly higher than that of PM 2.5,and nitrogen oxidation ratio and sulfur oxidation ratio increased significantly along with the increase of relative humidity,indicating that the formation of sulfate and nitrate was the crucial source of PM 2.5 pollution.Backward trajectories of air masses in SPD showed that PM 2.5 pollution in Hangzhou and Huzhou was influenced by air masses from Jiangsu,Anhui and other cities in Zhejiang,that PM 2.5 pollution in Ningbo and Zhoushan was influenced by air masses from Shanghai,Jiangsu,Anhui and the East China Sea,and that PM 2.5 pollution in Jinhua was influenced by air masses from native sources and adjacent Hangzhou and Shaoxing.

关 键 词：PM 2.5 二次转化 区域传输 

分 类 号：F42[经济管理—产业经济]