Method for Soil Moisture and Surface Temperature Estimation in the Tibetan Plateau Using Spaceborne Radiometer Observations
Method for Soil Moisture and Surface Temperature Estimation in the Tibetan Plateau Using Spaceborne Radiometer Observations
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DOI：
10.1109/lgrs.2014.2326890
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发表时间：
2015
影响因子：
4.8
通讯作者：
J. Zeng;Zhen Li;Quan Chen;H. Bi
中科院分区：
文献类型：
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作者：
J. Zeng;Zhen Li;Quan Chen;H. Bi
基于物理基础认为的36。然后，利用先进微波扫描辐射计（AMSR-E）观测数据，将新的地表温度模型整合到本文提出的土壤水分反演算法中。该算法将植被光学深度和粗糙度合并为一个综合因子，避免了对植被光学深度和粗糙度进行不可靠的假设和使用辅助数据来获取这两个参数。最后，通过密集那曲网络的地面测量对算法进行了验证，并与NASA AMSR-E和SMOS官方算法进行了比较。结果表明，该算法在那曲网络区域的土壤水分反演精度明显高于其他两种卫星算法。该算法可以应用于植被稀疏的区域，但可能不太适合植被密集的表面。
A method for soil moisture and surface temperature estimation in the Tibetan Plateau (TP) using spaceborne radiometer observations was presented. Based on the physical basis that the 36.5-GHz (Ka-band) vertical brightness temperature is highly sensitive to the topsoil temperature, a new surface temperature model was developed using all ground measurements available from three networks named CAMP/Tibet, Maqu, and Naqu, established in the TP, which can significantly improve the accuracy of surface temperature derived from the land parameter retrieval model (LPRM). Then, the new surface temperature model, which was calibrated with in situ data, was integrated into the soil moisture retrieval algorithm proposed in this letter using Advanced Microwave Scanning Radiometer (AMSR-E) observations. The algorithm combines the vegetation optical depth and roughness into an integrated factor to avoid making unreliable assumptions and using auxiliary data to get these two parameters. Finally, the algorithm was validated by ground measurements from the dense Naqu network and was compared with NASA AMSR-E and Soil Moisture and Ocean Salinity (SMOS) official algorithms. The results show that the proposed algorithm can provide much more accurate soil moisture retrievals than the other two satellite algorithms in the Naqu network region. The algorithm can be applied to the areas with spare vegetation but may not be very suitable for densely vegetated surfaces.