Cloud Climatology Characteristics Of China From ISCCP Data

Based on the cloud amount or 18CCP D2, the spatial distribution characters and the time variation of cloud amount over 5 regions of China are analyzed using System cluster analysis method. And we concluded that in the east of China the cloud amount increased and decreased in the north west of China .The positive correlation between cloud amount and precipitation and the negative correlation between cloud amount and OLR are found by calculating their correlation coefficient separately. We also discussed the climate characters of total cloud amount in Tibetan plateau, gave spatial distribution characters and yearly, seasonally, daily variation properties of cloud amount according to moisture condition, topographic dynamics and circulation character over Tibetan plateau. The decreasing of cloud amount in 1994-1998 is predicted also. Comparing with station observations, the rationality of ISCCP-D2 data was validated. And the good correlation in summer was found by analyzing the correlation between ISCCP-D2 cloud amount and OLR. We also analyzed the period of cloud amount over Tibetan plateau and predicted that the cloud amount was to be increased in 1994-1998.The remote correlation between cloud amount over Tibetan plateau and precipitation in north China, south China and the middle-down reaches of Yangtze river are done and concluded if there is a lot of cloud, then the precipitation is heavy in north China, south China and the middle-down reaches of Yangtze river at the same time, little in these three regions 6 months later.