2018年中国长江三角洲地区气溶胶的垂直分布特征

Characteristics of Aerosol Vertical Distribution over the Yangtze River Delta Region of China in 2018

利用主动式遥感卫星云-气溶胶激光雷达和红外探测者卫星观测(CALIPSO)提供的激光雷达资料,重点分析了2017-12~2018-11中国长江三角洲地区对流层大气中532 nm气溶胶消光系数,气溶胶退偏比,气溶胶色比以及各类型气溶胶的时空变化特征.对气溶胶的光学参数随高度变化的研究表明,与对流层高空相比,一般在对流层低空中气溶胶消光能力更强,气溶胶粒子更规则,气溶胶粒径更小.对气溶胶的光学参数随季节变化的研究表明,与冬春季相比,一般夏秋季在对流层高空中气溶胶消光能力更强,在2 km以下气溶胶粒子更规则,在对流层高空中气溶胶粒径的范围更大.长江三角洲地区全年中污染沙尘气溶胶出现的频率最高,为37.481 6%,夏秋季烟尘、污染大陆与洁净海洋气溶胶出现的频率比冬春季高,而夏秋季沙漠沙尘气溶胶出现的频率相对较低.

Based on the lidar data provided by cloud-aerosol lidar and infrared pathfinder satellite observations(CALIPSO)from December 2017 to November 2018,the temporal and spatial variation characteristics of 532 nm aerosol extinction coefficient,aerosol depolarization ratio,aerosol color ratio,and various types of aerosols in the troposphere over the Yangtze River Delta region of China were analyzed in detail.The altitude variation of aerosol optical parameters showed that the extinction ability of aerosols was generally stronger in the lower troposphere than that in the upper troposphere,the shape of particles was generally more regular in the lower troposphere than that in the upper troposphere,and the size of particles was generally smaller in the lower troposphere than that in the upper troposphere.The seasonal variation of aerosol optical parameters showed that the extinction ability of aerosols in the upper troposphere was generally stronger in summer and autumn than that in winter and spring,the shape of particles below 2 km was generally more regular in summer and autumn than that in winter and spring,and the size range of particles in the upper troposphere was generally larger in summer and autumn than that in winter and spring.The occurrence frequency of polluted dust aerosols over the Yangtze River Delta throughout the year was the highest(37.481 6%).The occurrence frequency of smoke aerosols,polluted continental aerosols,and clean marine aerosols in the troposphere was higher in summer and autumn than that in winter and spring.However,the occurrence frequency of dust aerosols in summer and autumn was relatively low.