利用MODIS遥感数据结合地表气象观测,在对SEBS模型物理参数进行计算和灵敏度分析的基础上,得到黑河流域春、夏、秋、冬四季不同气象条件和不同下垫面条件下的地表蒸散发。依靠黑河流域综合研究站—临泽站蒸散发仪观测的蒸散发验证遥感反演的精度,结果表明遥感反演的地表蒸散发精度较高,模型参数方案可行。这一方法可以在流域尺度上揭示出流域不同下垫面的蒸散发随季节变化的空间特征。最后,利用遥感反演的蒸散发与地面站点蒸发器实测的水面蒸发量和Penman-Monteith公式计算的蒸发量进行对比分析不同下垫面条件不同季节地表潜在蒸发能力和干湿状况。

The evapotranspiration in the Heihe River basin in different season under different underlying conditions are calculated according to the remote sensing data combining with meteorological observation data. The Surface Energy Balance System (SEBS) model is adopted and the related land surface biophysical parameters are obtained from reverse calculation and determined based on sensitivity analysis. The validity and accuracy of the calculated evapotranspiration are verified by lysimeter observation data obtained from a hydrological station in the river basin. The analysis on obtained evapotranspiration shows that by using this reverse calculation approach the seasonal spatial variation of evapotranspiration for different underlying conditions in river basin scale can be revealed. Finally, the evapotranspiration values obtained from reverse calculation are used together with those calculated by Penman-Montheith formula to analyze the land surface potential evaporation and moisture situation in different seasons under different underlying conditions.