中文摘要：

利用1986-2006年PATMOS-X、ISCCP总云量和低云量产品与中国区域地面台站观测的总云量、低云量资料进行对比分析，对比不同来源、不同观测方法造成的云量数据在时间、空间上的差异，为资料使用者提供参考。结果表明，与台站观测资料相比，无论PATMOS．X还是ISCCP其总云量数据的空间分布、与站点观测数据的格点相关性均好于低云量数据；PATMOS—X总云量、低云量多年平均的空间分布较ISCCP更接近站点观测；中国区域平均低云量的线性趋势PATMOS—X与站点观测一致，表现为显著的上升趋势，而ISCCP低云量数据则呈现微弱的下降趋势。

英文摘要：

PATMOS-x is a project to derive atmospheric and surface climate records from NOAA＇s Advanced Very High Resolution Radiometer （AVHRR）.The longest global remotely sensed cloud imagery record is from AVHRR, located on the National Oceanic and Atmospheric Administration（NOAA） polar-orbiting satellites. The PATMOS-x provides multiple products （cloud, aerosol, surface and radiometric） on the same grid using a common processing path. The International Satellite Cloud Climatology Project （ISCCP） was established in 1982 as part of the World Climate Research Program （WCRP） to collect weather satellite radiance measure- ments and to analyze them to infer the global distribution of clouds, their properties, and their diurnal, seasonal and interannual variations. This study focused on the comparison of cloud amount from PATMOS-x and ISC- CP with ground observation over China. The spatial and temporal differences of low cloud amount and total cloud amount are investigated using PATMOS-x data, ISCCP data and ground observation in 1984-2006. The quantitative analysis results show that the distribution of total cloud amount from PATMOS-x and 1SCCP are better than that of low cloud amount according to that of ground observation. And it is the same as grid-based correlation with ground observation. The distribution of low cloud amount from PATMOS-x is more similar with ground observation than that oflSCCR The low cloud amount from PATMOS-x and from ground observa- tion over China both show obviously linear increasing trend.