珠三角秋冬季节长时间灰霾污染特性与成因  

Causes and Pollution Characteristics of Long-time Haze Episodes in the Pearl River Delta Region during the Seasons of Autumn and Winter

作　　者：区宇波[1] 岳玎利[1] 张涛[1] 周炎[1] 袁鸾[1] 谢敏[1] 

机构地区：[1]广东省环境监测中心国家环境保护区域空气质量监测重点实验室,广东广州510308

出　　处：《中国环境监测》2014年第5期16-20,共5页Environmental Monitoring in China

基　　金：广东省自然科学基金重点项目"珠江三角洲秋季PM2.5重要来源及区域输送特征研究"(S2012020011044);国家自然科学基金青年基金项目"珠三角地区新粒子生成特性及其二次组分的作用"(41303075)

摘　　要：利用珠三角大气超级站2012年10月与2013年1月能见度、不同粒径颗粒物与BC质量浓度、气溶胶光散射系数、O3、相对湿度等在线监测数据,分析秋冬季节2次持续时间超过10 d的长时间灰霾过程污染特性与成因。结果表明,冬季灰霾过程中气溶胶吸光系数和光散射系数对大气总消光系数的贡献分别为13%和67%;PM2.5、PM1占PM10质量浓度分别为66%和39%;较高的PM2.5与BC日均浓度相关系数(R2=0.88)体现了一次排放对颗粒物质量浓度及能见度的显著影响。秋季灰霾过程中气溶胶吸光系数和光散射系数对大气总消光系数的贡献分别为11%和69%,由BC导致的吸光效应较冬季下降了约20%;PM2.5和PM1占PM10质量浓度比例分别为68%和45%,均高于冬季;O3浓度日最大小时值的平均值接近冬季的2倍;二次来源对PM2.5浓度升高和能见度下降起主导作用。来自不同方向的2种气团在珠三角僵持,大气扩散条件差是导致这2次灰霾过程的重要外在条件,应成为灰霾预报预警的重点关注对象。Based on the on-line measurement of visibility,mass concentrations of size resolved particles and black carbon,particle light-scattering coefficient,ozone concentration and relative humidity etc. during October of 2012 and January of 2013 at the atmospheric supersite in the Pearl River Delta Region,the properties and causes of two so called long-time haze episodes lasting for over ten days were analyzed. It showed that during the winter episode,particle light-absorption coefficient and light scattering coefficient accounted for 13% and 67% in the total atmospheric extinction coefficient,respectively; PM2. 5and PM1contributed66% and 36% to PM10mass; the higher correlation coefficient between daily PM2. 5and BC（ R2= 0. 88） indicated the significant influence of primary emission on the fine particles and visibility. During the autumn episode,particle light-absorption coefficient and light scattering coefficient accounted for 11% and 69% in the total atmospheric extinction coefficient,with 20% lower lightabsorption effect of BC than winter episode; the contributions of PM2. 5and PM1 to PM10were 68% and 45%,both larger than winter episode; the average value of the daily maximum O3- 1 h was nearly twice of that in winter episode; secondary transformation played a major role in the particle mass concentration increase and visibility degradation. The conditions with two kinds of air masses in different directions stalemating over PRD region and weak diffusion were important external conditions for the two long-time haze episodes,and should be taken as one of the focuses for haze forecasting and warning.

关 键 词：能见度 颗粒物质量浓度 消光系数 大气氧化性 气团来源 

分 类 号：X823[环境科学与工程—环境工程]