【摘要】 利用被动微波遥感数据TMI和GAME-Tibet加强观测期的地面观测数据,改进和发展了一个被动微波遥感反演地表温度、土壤湿度和植被含水量的三维查表算法(3-D LUT),并在青藏高原中部中尺度范围内进行了反演试验.对1998年7月1日的数据进行了个例处理,给出了3个地表参数的空间分布结果.进一步考虑了高原对流云对反演结果的影响,对5个月的TMI数据进行了10天的合成处理,利用合成图像运行算法得到了10天平均的结果.结果显示1998年5-9月5个月的土壤湿度反演结果的时空分布与实际情况符合较好;从选取的几个测站的数据比较看,去云处理后得到的土壤湿度反演结果有了明显改善.更多还原

【Abstract】 In addition to investigating the rainfall over the Tibetan Plateau, Microwave Imager observations on board of the satellite Tropical Rainfall Measurement Mission (TRMM) have also been used to retrieve land surface parameters, such as surface temperature (Ts), vegetation water content (wc), and volumetric soil surface moisture (φv). A three dimensional Look-up Table (LUT) scheme, by using one band brightness temperature, a ’Polarization Index’ (PI), and an ’Index for Soil Wetness’ (ISW), was developed for this purpose, which can retrieve the three basic parameters Ts, wc, and φs simultaneously. Considering that there were still clouds as well as heavy rainfall disturbance in deriving surface parameters over the Tibetan Plateau, 10-day composite TMI images were used. For the five months from May to September 1998, the distribution of surface parameters of every ten days on the mesoscale intensive experimental region of GAME-Tibet was evaluated. The results were compared with field observations; particularly for the mostly concerned surface soil moisture, the results were quite acceptable. 3-D LUT is an easy and effective method to be used in the passive microwave remote sensing.更多还原