基于CloudSat资料对中国低纬度陆地区域卷云物理特征的研究

Characteristics of clouds properties in cirrus clouds in low latitude land areas of China with the CloudSat data

利用2008年9月—2016年8月的CloudSat卫星资料对发生在我国低纬度陆地区域(5°~36.5°N,78°~124°E)的卷云物理特征进行统计分析,并分别讨论东部沿海、中部、西部3个子区域的卷云物理特征的季节变化。结果表明:卷云的整层发生率西部地区整体低于中部与东部沿海地区。3个子区域整层发生率均在夏季最高、冬季最低。卷云的主要发生高度在5.04~18.71 km,垂直分布中卷云发生率的最大值出现在春季中部地区,为15.34%,高度为9.83 km。冰水路径最大值出现在夏季的东部沿海,液水路径最大值在秋季的西部地区。冰水含量、冰粒数浓度、冰粒有效半径的主要分布高度与卷云的发生高度一致,液水含量、液滴数浓度、液滴有效半径的主要分布高度在5.04~9.35 km。3个子区域卷云冰水含量、冰粒数浓度、冰粒有效半径垂直分布中大多集中在中上部;液水含量垂直分布主要集中在分布高度的中下部。四季卷云雷达反射率因子的最大值在-19.89~-16.78 dBZ,分布高度在7.19~10.55 km。

By using the CloudSat satellite data from September 2008 to August 2016,the physical characteristics of cirrus clouds occurring in China s low latitude regions(5°-36.5°N,78°-124°E)were statistically analyzed and the physical characteristics of cirrus clouds in the eastern coastal,central and western sub-regions change in the four seasons were discussed.Results show that the probabilities in cirrus clouds at total altitudes in the western region is lower than in the central and eastern coastal regions.The probabilities in cirrus clouds at total altitudes of the three sub-regions was highest in summer and lowest in winter.The main occurrence height of cirrus clouds is between 5.08 km and 18.71 km.The maximum occurrence rate of cirrus clouds in the vertical distribution occurs in the central part of summer,which is 15.34%,and the height is 9.83 km.The maximum value of ice water path occurs in the eastern coast in summer,and the maximum value of liquid water path occurs in the western region in spring.The main distribution heights of ice water content,ice particle concentration and ice particle effective radius are consistent with the occurrence height of cirrus cloud,and the main distribution heights of liquid water content,droplet concentration and droplet effective radius are 5.08-9.35 km.In the three sub-regions,the vertical distribution of cirrus cloud ice water content,ice particle concentration,and ice particle effective radius are mostly concentrated in the middle and upper part;the vertical distribution of liquid water content is mainly concentrated in the middle and lower part of the distribution height.The maximum reflectivity factor of the four seasons cirrus cloud radar is-19.89--16.78 dBZ,and the distribution height is 7.19-10.55 km.