The analysis of sources of ambient light extinction coefficient in summer time of Beijing city
北京市夏季大气消光系数的来源分析

Using the measured concentrations of ambient particles and gaseous species in the summer of 1999, the averaged contributions of light extinction are calculated by Mie model. It is found that the total extinction coefficient is 0.388?km~(-1). The major component of b_(ext) is b_(sp) (70.5% of b_(ext)), followed by b_(ap) (22.3% of b_(ext)), b_(sg) (3.6% of b_(ext)) and b_(ag) (3.5% of b_(ext)). The light extinction is mainly from particles, which accounts for more than 90% of total extinction coefficient.