一种可同时反演土壤水分与地表温度而无需植被及地表粗糙度辅助参数的微波辐射计算法.pdf

IEEE GEOSCIENCE AND REMOTE SENSING LETTERS, VOL. 12, NO. 1, JANUARY 2015 97 Method for Soil Moisture and Surface Temperature Estimation in the Tibetan Plateau Using Spaceborne Radiometer Observations Jiangyuan Zeng, Zhen Li, Quan Chen, and Haiyun Bi Abstract—A method for soil moisture and surface temperature signals received by passive sensors are also affected by many estimation in the Tibetan Plateau (TP) using spaceborne radiome- other factors, such as vegetation cover, surface roughness, and ter observations was presented. Based on the physical basis that surface temperature [2]. Among them, surface temperature is a the 36.5-GHz (Ka-band) vertical brightness temperature is highly very important parameter. It influences the brightness temper- sensitive to the topsoil temperature, a new surface temperature model was developed using all ground measurements available ature through interactions with the surface emissivity and thus from three networks named CAMP/Tibet, Maqu, and Naqu, es- must be eliminated for soil moisture retrieval. Thermal infrared tablished in the TP, which can significantly improve the accuracy (TIR) is an effective and widely used means to obtain surface of surface temperature derived from the land parameter retrieval temperature. However, TIR is vulnerable to the influence of model (LPRM). Then, the new surface temperature model, which clouds and may experience signal saturation easily under the was calibrated with in situ data, was integrated into the soil mois- condition of heavy vegetation. The former is a great limitation ture retrieval algorithm proposed in th