北京一次严重雾霾过程气溶胶光学特性与气象条件

摘要

对北京地区2013年10月2~7日一次严重雾霾过程中的气溶胶光学特性开展研究,分析了气象条件对雾霾过程的影响,并结合HYSPLIT模型分析污染物的来源.结果表明,在污染天气中气溶胶光学厚度、?ngstr?m波长指数、细模态体积尺度谱峰值浓度远高于清洁天.10月5日雾霾最为严重,440nm波长处气溶胶光学厚度高达3.89.在雾霾发生前后,单次散射反照率日均值随波长增大而增大,而在10月5日,单次散射反照率值随波长增加先增大后减小,在675nm波长处达到最大值0.965.雾霾过程中大气气溶胶以强散射型细粒子为主,人为因素贡献较大,且受气象条件影响明显.%Results of aerosol optical properties research during a severe haze-fog episode from 2 October to 7 October 2013 in Beijing were studied. The meteorological effects on the haze-fog process were investigated, and the pollution sources were analyzed with the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model. The values of aerosol optical thickness (AOT), ?ngstr?m wavelength exponent (AE), and the peak of aerosol volume size concentration in fine mode in polluted days were much higher than that of clean days. The daily average single scattering albedo (SSA) increased with the increasing of wavelength in the earlier and later period of the intensive haze-fog episode. On October 5, the most serious haze process was happened and the AOT of wavelength 440nm was raised as much as 3.89. The SSA firstly increased and then decreased with the increasing of wavelength. The maximum SSA value was 0.965 at the wavelength of 675nm. During the haze-fog episode, fine particles with strong scattering characteristics were dominated which was mainly contributed by human factors, and was significantly influenced by meteorological parameters.