在特定环境中气溶胶组分光学特性的分析

The Analysis of the Optical Properties of Aerosol Components in Three Particular Environments

基于Mie散射的OPAC软件包,分析了在激光雷达探测气溶胶时的3种特定环境(大陆洁净、大陆污染、海上污染)下各种气溶胶组分对光学特性(消光系数、散射系数、吸收系数、激光雷达比)的影响,对比了在550、1000 nm这2个波长下的变化规律.研究结果表明:在550、1000 nm这2个波长下不同环境中气溶胶组分的消光系数、散射系数随水滴数浓度的增加均呈线性递增,大陆洁净型和大陆污染型气溶胶环境的吸收系数变化均比较缓慢.在海上污染型气溶胶环境中,当气溶胶组分为积聚模态海盐和粗模态海盐时,水滴数浓度的变化率为0,这表明在这2种气溶胶组分环境下,吸收系数不随水滴数浓度的变化而变化;激光雷达比受雷达波长和气溶胶环境组分2个因素的影响,该值在大陆污染型气溶胶环境下的变化最为明显,在水溶性和非水溶性组分下大幅递减,而在煤烟组分下大幅递增.

Based on the OPAC software package of Mie scattering,the effects of various aerosol components on optical properties(extinction coefficient,scattering coefficient,absorption coefficient and lidar ratio)are analyzed when lidar detects aerosols in three specific environments(continental clean,continental polluted and maritime polluted).And the changing regular under the two wavelengths(550 nm,1000 nm)are further compared.The results show that the extinction coefficients and scattering coefficients of aerosol components in different environments at two wavelengths increase linearly with the increase of number concentration,and the absorption coefficients of the continental clean and continental polluted aerosol environments change slowly.In the maritime polluted aerosol environment,when the aerosol components are the accumulation mode sea salt and the coarse mode sea salt,the change rate of the water droplet number concentration is zero,which shows that the absorption coefficient doesn′t change with the water droplet in the environment of the two aerosol components.The lidar ratio is affected by two factors(the wavelength of the radar and the composition of the aerosol environment),the lidar ratio changes obviously in the continental polluted aerosol environment.The ratio is greatly increased under the soot component.