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利用2001年11月—2005年10月＂云与地球辐射能量系统（CERES）＂辐射和云资料SYN（Syn-optic Radiation Fluxes and Clouds）,分析了青藏高原（下称高原）地区不同高度云辐射强迫的时空变化特征。结果表明：（1）高原整体为云强迫正、负值的过渡区域,这种过渡性有显著的季节差异和区域划分。高原东南部表现出较强的冷却效应,其西部和东北部干旱区在冬、春季表现为较弱的加热效应。（2）高云、高的中云和低的中云对云短波辐射强迫的季节变化都有贡献,其中中云是导致区域差异的主要因素;云长波辐射强迫的区域差异不明显,但季节差异显著,这主要是由高的中云和高云的变化引起的,且云量是主要的影响因子,高云云量虽小但其影响不可忽视。（3）高云在高原地区产生净加热效应,高的中云既产生加热作用也产生冷却作用,低的中云产生净冷却效应。（4）云短波辐射强迫在云辐射强迫的日变化中仍然占主导地位,日变化的区域差异主要是由云量引起的。白天,在云短波辐射强迫的日变化中,低的中云贡献更大。高云对云长波辐射强迫的日变化贡献主要在晚上,低的中云在夜间对云长波辐射强迫有抑制作用。“,”The cloud and radiation data,archived in CERES(Clouds and the Earth′s Radiant Energy System) SYN(Synoptic Radiation Fluxes and Clouds) product,are applied to gain a better understanding of the temporal and spatial variations of cloud radiation forcing over the Qinghai-Xizang Plateau(QXP) from November 2001 to October 2005.The results indicate four important points: Firstly,the whole QXP is the transition area of cloud radiation forcing,and this transition has significant seasonal and regional variations.The southeast of QXP makes a cooling effect,the western and northeastern QXP regions,an arid area,showed a weaker warming effect.Secondly,high cloud,upper-middle cloud and lower-middle clouds all contribute to the seasonal and regional differences of cloud shortwave radiation forcing,and the middle cloud is the main factor of regional differences;regional differences of longwave radiation forcing is not so obvious,but it has significant seasonal difference,which is mainly caused by the high cloud and upper-middle clouds,and cloud amount is a main factor of influence.Although the cloud amount of high cloud is small,but its impact is unnegligible.Thirdly,over QXP,high cloud causes a net heating effect,upper-middle clouds have both heating effect and cooling effect,and low cloud cause a net cooling effect.Fourthly,for the diurnal variation of cloud radiation forcing,the shortwave plays a dominating role.The significant regional differences of diurnal variation are mainly caused by the cloud amount.During the daytime,the lower-middle clouds have the greatest contribution on the diurnal variation of shortwave radiation.At night,the high cloud plays an important role of diurnal variation of shortwave radiation,while the lower-middle clouds inhibit the for longwave radiation forcing.