Research of cloud vertical distribution around China based on occultation data

Based on the idea that retrieving cloud boundary by using the mutation of relative humidity profile when it comes into or out of cloud, this paper gets the statistical analysis of cloud vertical structure around China by using(COSMIC) data from January 2007 to January 2009. The results show that clouds around China are mainly single-layered, double-layered and thriple-layered, probability of cloud occurrence shows higher in summer and lower in winter, and it has different changing trends along warp and weft direction. The cloud amount around China nearly obeys bimodal distribution and it has some seasonal variation regularity. Cloud (base or top) height, cloud thickness and clear-sky distance between two consecutive layers have different ranges, which are larger in summer and lower in winter