中国大范围雾霾期间大气污染特征分析

Analysis of a wide range haze pollution in China

为分析我国2013年1月份大范围雾霾成因及特点,在收集相关污染物与气象数据的基础上,运用主成分及相关性分析,对雾霾期间我国8个重点城市大气细颗粒物(PM2.5)浓度、粒径分布,时空变化规律,雾霾与气象因素的关系以及雾霾期间各城市大气污染指标的主成分及相关性进行了分析.结果显示雾霾期间8个城市PM2.5平均超标2.34倍,11～14号超标最为严重,PM2.5/PM10浓度比值平均为0.72,高湿、逆温、低压、静风等气象条件有利于雾霾的形成,PM2.5与SO2,NO2等表现出较好的相关性,主成分分析表明多数城市表现出明显的复合污染特征.此次雾霾是以特殊气象条件为主导的机动车尾气及煤烟型复合污染引起的大范围污染现象.

To analyze causes and characteristics of a wide range haze in January 2013 in China, mass concentrations, size distribution and spatio -temporal variation of atmospheric particles in eight major cities were investigated, as well as correlations were analysed between haze and meteorological factors, principal component and correlation analysis also were investigated that of atmospheric pollution indicators in eight major cities during haze period. Results showed that mass concentrations of fine particles （ PM2.5 ） exceeded standard by 234% on average, with most serious from llth to 14th, the mean ratio of PM2.5/PM10 is 0.72. In addition, meteorological conditions with high humidity, thermal inversion, low pressure and calm wind are in favor of formation of haze. Strong correlations are found between PM2.5 and SO2 as well as NO2, principal component analysis indicated that combined pollution existed in many cities. The haze of wide range in January 2013 in China was caused by vehicle exhaust and coal fume combined pollution which additionally dominated by specifical meteorological conditions.