利用星载激光雷达研究云层垂直结构及其分布

Cloud vertical structure statistics from CALIPSO lidar observations

云的垂直结构(CVS)是云的重要特征量,在大气模式研究中有着有着十分重要的影响。利用CALIPSO星载激光雷达2007～2010年间Level 2 Version3的云数据对中国海域及其周边海域云的垂直结构及其分布随年度和区域的变化进行了统计分析。结果表明:层数不同的云在研究区域内发生的概率(COF)差别较大,云顶海拔高度(LTA)不同的云沿纬度方向的分布差异明显,LTA在10～20 km的云出现的概率较高而且大多出现于靠近赤道区域。由于有些云CALIPSO信号不能穿透,可能使云层数以及云顶高度的统计结果偏小。

The cloud vertical structure （CVS） acts an important aspect of cloud characteristics and at- mospheric model. The vertical distribution statistics of clouds over China Sea and adjacent sea area were derived from the Cloud Aerosol Lidar and Infrared Pathfinder Satellite Observations （CALIPSO） level 2 version 3 lidar cloud layer data from 2007 to 2010. The results show that the cloud occurrence frequencies （COF） of single and multi-layer clouds over the mentioned area are different, and the layer-top-altitude （LTA） occurrence frequencies have obvious difference with latitude. High clouds （10 - 20 km） have high occurrence frequency near equator. Because there are some opacity clouds, the result of layer-number and LTA may be smaller than the real situation.