中国东部地区气溶胶光学特性和类型特性分析

Analysis of Optical Characteristics and Type Characteristics of Aerosols in Eastern China

本文基于我国东部沿海岸线分布的Beijing-RADI、Beijing-CAMS、Xuzhou-CUMT、Taihu、Hong_Kong_PolyU、Hong_Kong_Sheung六个AERONET长期观测站点的光学厚度(AOD)、Angstrom指数(AE)、单次散射反照率(SSA)、细粒子百分比(FMF)四种气溶胶的物理光学特性观测产品,结合Terra/Aqua MODIS Level2 C6 AOD产品,研究了我国东部地区气溶胶时空变化特性及类型特性。研究表明:1)北京、徐州、太湖、香港地区四个地区地基的AOD年均值徐州>太湖>北京>香港地区,依次为0.805±0.129、0.775±0.069、0.664±0.197、0.519±0.125;2)在AERONET站点处,MODIS AOD年均值检测值太湖>徐州>香港地区>北京,依次为0.902±0.227、0.772±0.082、0.547±0.064、0.517±0.234,与地基检测值依次相差22.2%、4.1%、5.5%、16.3%;3)AE年均值香港地区>太湖>徐州>北京,依次为1.314±0.054、1.213±0.084、1.198±0.104、1.118±0.078,表明中国东部地区污染物的粒径从北往南逐渐减小;4)北京、徐州、太湖、香港地区四个地区均以弱吸收型细粒子所占比重最大,依次为38.29%、44.99%、44.30%、48.14%,中度吸收型细粒子和强散射细粒子次之,其他类型的粒子均较少。

The aerosol optical depth(AOD),Angstrom exponent(AE),single scattering albedo(SSA),and fine mode fraction(FMF)were extracted through six AERONET long-term observation sites,including Beijing-RADI,Beijing-CAMS,Xuzhou-CUMT,Taihu,Hong_Kong_PolyU,and Hong_Kong_Sheung locating along the coastline of eastern China,and were processed using the Terra/Aqua MODIS level2 C6 AOD products to study the aerosol variation characteristics and type characteristics of aerosols in eastern China.It is found that 1)the annual average value of AOD decreases from Xuzhou to Taihu,Beijing,and Hong Kong region in the order 0.805±0.129、0.775±0.069、0.664±0.197,and 0.519±0.125,respectively;2)at the AERONET site location,the annual average value of MODIS AOD decreases from Taihu to Xuzhou,Hong Kong region,and Beijing in the order 0.902±0.227,0.772±0.082,0.547±0.064,and 0.517±0.234 and the ground detection differences are 22.2%,4.1%,5.5%,and 16.3%,respectively;3)the annual average AE value decreases from Hong Kong to Taihu,Xuzhou,and Beijing in the order 1.314±0.054、1.213±0.084、1.198±0.104、and 1.118±0.078,respectively,indicating that the average size of air pollutant particulates in eastern China decreases from north to south;4)the proportions of weakly absorbable fine particles are 38.29%,44.99%,44.30%,and 48.14% in the four regions of Beijing,Xuzhou,Taihu,and Hong Kong region,respectively,followed by moderate absorption fine particles and strong scattering fine particles.Other types of particles are found in lower concentrations.