为了分析造成合肥上空春季自由对流层气溶胶浓度分布高于其它季节的原因,本文对偏振 激光雷达2005～2008年期间春季常规测量和加密测量的数据结果进行 再分析,从中提取了137组气溶胶结构层进行统计研究,并对2008年3月2日的观测结果作了个 例分析。结果表明,特殊气溶胶结构层大多源于沙尘源区气溶胶粒子的 远距离传输,其影响高度70%分布在2～4 km范围内,退偏振比大于0.1的结构层占据85%,这些 结果可用于解释合肥春季自由对流层的气溶胶浓度分布偏高的原因。

Aerosol data measured by polarization lidar over Hefei in spring of 2005～2008 are analysed again. The observational results on Mar. 2nd, 2008 are used for case study and 137 samples of aerosol layers are investigated statistically. The results show that 70% of the average heights for these layers is ranged from 2 to 4 km, and the value of depolarization ratio for them, which is lager than 0.1, takes up to 85%, and these aerosol layers are sourced from the dust particles, which are transported in long range from the dust regions. These results can used to interpret why the aerosol concentration in free troposphere over Hefei in spring is higher than other seasons.