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利用Aqua卫星上同时搭载的AMSR-E和MODIS提供同步观测的微波和红外资料,反演青藏高原地区陆面微波比辐射率。结合MODIS反演的地表类型资料,分析该地区陆地微波比辐射率随地表类型、微波频率、不同时间尺度的变化特征。结果表明：该地区主要的3种地表类型中,草地比辐射率普遍高于裸地和灌木丛,并且后两者比辐射率的量值和变化趋势都很接近;陆面微波比辐射率随着频率增大而逐渐减小,并且垂直极化比辐射率随频率变化幅度较为显著。3种地表类型的比辐射率随年度变化很小,有一定的季节差异,而昼夜差异显著。不同地表的水平极化比辐射率差异幅度比垂直极化更加显著,能更有效地识别地表类型。“,”We utilized the synchronous observation of MODIS and AMSR-E on Aqua satellite to retrieve the microwave surface emissivity of Tibetan Plateau.Combining with the data of land surface types derived from MODIS observations,we further analyzed the variations of microwave emissivity with frequency,different time scales,and land types over Tibetan Plateau.The results show that among the three main land types in Tibetan Plateau,the emissivity over grass land is higher than that over barren and shrub land,and the two latter have very similar trend and close value.The land surface emissivity decrease with increasing frequency,and the variation range at vertical polarization is more remarkable than that at horizontal polarization with increasing frequency.For different time scale,the annual variation is small,and the seasonal variation is a little bit,and the diurnal one is quite obvious.The differences of horizontal polarized emissivity over different land types are more obvious than those of vertical one so that the former emissivity could be more useful to classify land surface types.