利用2008年冬季和夏季星载激光雷达CALIOP版本3一级数据产品,分别对北半球两个季节CALIOP 532 nm垂直通道和平行通 道的瞬态响应进行统计分析,对比可知北半球冬季和夏季的瞬态响应具有明显的差异。由于南极大陆和格陵兰岛常年 被冰雪覆盖,利用CALIOP在该区域的数据得到532 nm垂直和平行通道的瞬态响应函数作为冰雪后向散射特性,并以 此作为判断冰雪的依据。北半球冬季有41.8%的数据点和夏季数据点的特性保持一致,表明这些点未被冰雪 覆盖。而其它58.2%的数据点的特性和南极大陆以及格陵兰岛数据点特性一致,表明这些点被冰雪覆盖。

The transient responses of the CALIOP instrument in the 532 nm parallel and perpendicular channel are derived and analyzed from the CALIOP level 1 version 3 products in the winter and summer of 2008. The results show that there is great difference between winter and summer in northern hemisphere. For the reason that Antarctic and Greenland are almost entirely covered by snow and ice all the year round, the characteristic of transient response on these land cloud be a basis for judging whether the transient response is caused by snow or ice in somewhere else. The distribution statistics of about 41.8% samples in winter are the same as that of the samples in summer in northern hemisphere. It means these areas are not covered by snow and ice. The other 52.8% samples’ statistics are consistent with the samples on Antarctic and Greenland, indicating that these areas are covered by snow and ice.