华北地区霾期间对流层中低层气溶胶垂直分布

基于美国宇航局(NASA)的CALIPSO星载激光雷达监测数据,通过分析总后向散射系数、体积退偏比和色比,对华北地区2007年1月1日至2008年12月31日期间出现灰霾时对流层中低层气溶胶光学和微物理特性的垂直分布进行了研究.结果表明:灰霾期间对于4 km以下的对流层中低层大气总体来说,非球形气溶胶出现频率略高于球形气溶胶,小粒径气溶胶出现频率高于大粒径气溶胶.在4 km以下的大气中,气溶胶出现频率在1 ～2 km高度范围内最高,在2～3 km高度范围内最低；球形气溶胶在2～3 km高度范围内出现频率最高,非球形气溶胶出现频率在1 ～2 km高度范围内最高；大粒径气溶胶在l～2 km高度范围内出现频率最高,小粒径气溶胶在0～1 km高度范围内出现频率最高.

Vertical distribution of aerosols in middle and low troposphere in Northern China during haze periods

Based on the lidar observation data from CALIPSO satellite of National Aeronautics and Space Administration (NASA), the vertical distribution of optical and micro-physical properties of aerosols in middle and low troposphere in northern China during the haze periods from January 1, 2007 to December 31, 2008 were characterized by analyzing total attenuated backscatter coefficient, volume depolarization ratio and color ratio. The results showed that during the haze periods, for middle and low troposphere below 4 km, the frequency of spherical aerosol particles was slightly higher than that of non-spherical aerosol particles and the frequency of small particles was higher than that of large particles. The frequency of aerosols was the highest at 1~2 km altitude and the lowest at 2~3 km altitude; the frequency of spherical aerosols was the highest at 2~3 km altitude and that of non-spherical aerosols was the highest at 1~2 km altitude; the frequency of large aerosol particles was the highest at 1~2 km altitude and that of small ones was the highest at 0~1 km altitude.