珠江三角洲大气光化学氧化剂(O_(x))与PM_(2.5)复合超标污染特征及气象影响因素  

Characteristics and Meteorological Factors of Complex Nonattainment Pollution of Atmospheric Photochemical Oxidant(O_(x))and PM_(2.5)in the Pearl River Delta Region,China

作　　者：颜丰华 陈伟华 常鸣 王伟文 刘永林 钟部卿 毛敬英 杨土士 王雪梅 刘婵芳 YAN Feng-hua;CHEN Wei-hua;CHANG Ming;WANG Wei-wen;LIU Yong-lin;ZHONG Bu-qing;MAO Jing-ying;YANG Tu-shi;WANG Xue-mei;LIU Chan-fang(Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for Environmental Quality,Institute for Environmental and Climate Research,Jinan University,Guangzhou 510443,China;Shenzhen Environmental Monitoring Center,Shenzhen 518049,China)

机构地区：[1]暨南大学环境与气候研究院,粤港澳环境质量协同创新联合实验室,广州510443 [2]深圳市环境监测中心站,深圳518049

出　　处：《环境科学》2021年第4期1600-1614,共15页Environmental Science

基　　金：广东省科技创新战略专项(2019B121205004);深圳市环境科研课题项目(GXZX-19042SZGK);国家环境保护区域空气质量监测重点实验室开放基金项目(SRAQM02202001);暨南大学高性能计算公共服务平台项目。

摘　　要：基于粤港澳珠江三角洲区域空气监测网络12个监测子站的大气污染物数据,梳理2013~2017年大气光化学氧化剂O_(x)(NO_(2)+O_(3))与PM_(2.5)质量浓度的变化趋势.O_(x)+PM_(2.5)复合超标污染定义为NO_(2)和PM_(2.5)质量浓度日平均值以及O_(3)浓度日最大8 h平均值(O_(3)MDA8)同时超过二级浓度限值,分析了不同类型站点复合超标污染的时空分布特征以及气象因素影响.结果表明,2013~2017年珠三角PM_(2.5)年均质量浓度由(44±7)μg·m^(-3)下降至(32±4)μg·m^(-3),实现PM_(2.5)连续3 a达标.O_(x)年均质量浓度由2013年(127±14)μg·m^(-3)下降至2016年(114±12)μg·m^(-3),2017年反弹至(129±13)μg·m^(-3),O_(3)浓度上升明显(10μg·m^(-3)).以O_(3)为首要污染物的污染过程占比由2013年33%增多至2017年78%,多个城市同时发生污染的区域特征明显.研究时段内O_(x)+PM_(2.5)复合超标污染事件共发生60次,主要在城区站点(78%)和郊区站点(22%).秋季发生复合超标污染天数最多(52%),是因为强太阳辐射有利于臭氧生成,大气氧化性增加,进而促进了PM_(2.5)二次生成.造成珠三角复合超标污染的天气形势主要为高压出海型(43%)、高压控制型(30%)和热带低压型(27%).就具体气象因素而言,气温在20~25℃且相对湿度在60%~75%的范围内时,复合超标污染事件发生占比最高(22%).在O_(3)重污染过程中,夜间高湿和低风速使得NO_(2)和PM_(2.5)浓度显著上升,日间高温加剧了复合超标污染.Based on the atmospheric pollutant data from twelve monitoring sites in the Guangdong-Hong Kong-Macao Pearl River Delta Regional Air Quality Monitoring Network,the mass concentration trends of atmospheric photochemical O_(x)idants(O_(x),NO_(2)+O_(3))and PM_(2.5)during 2013-2017 were studied.The complex nonattainment pollution of O_(x)and PM_(2.5)is defined as the daily average mass concentration of NO_(2)and PM_(2.5)and daily maximum 8 h average(O_(3)MDA8)mass concentration of O_(3)simultaneously that exceeds the Chinese gradeⅡnational air quality standard.The characteristics and meteorological factors that influence the complex nonattainment pollution of O_(x)and PM_(2.5)at different types of areas were analyzed.The results indicate that from 2013 to 2017,the annual average mass concentration of PM25 in the Pearl River Delta(PRD)region decreased from(44±7)μg·m^(-3)to(32±4)μg·m^(-3),which met the annual standard for three consecutive years.The annual average mass concentration of O_(x)decreased from(127±14)μg·m^(-3)in2013 to(114±12)μg·m^(-3)in 2016 and then showed a general rebound trend to(129±13)μg·m^(-3)in 2017 when 03 concentrations increased significantly(10μg·m^(-3)).The proportion of pollution processes with 03 as the primary pollutant increased from 33%in2013 to 78%in 2017,and the regional characteristics of simultaneous pollution in multiple cities have been highlighted.The complex nonattainment pollution of O_(x)and PM_(2.5)occurred 60 times during the study period,primarily in urban sites(78%)and suburban sites(22%).The largest number of days of complex nonattainment pollution occurred in autumn(52%)because of strong solar radiation that was conducive to ozone formation,and consequently,the high O_(x)idization of the atmosphere promoted the secondary generation of PM_(2.5).The weather conditions that caused the complex nonattainment pollution in the PRD mainly include outflow-high-pressures(43%),subtropical-high-pressures(30%),and tropical-depressions(27%).In terms of specific meteor

关 键 词：大气光化学氧化剂(O_(x)) PM_(2.5) 复合污染 天气形势 珠江三角洲(PRD) 

分 类 号：X51[环境科学与工程—环境工程]