Evapotranspiration estimation using remote sensing and its Spatial Distribution Characteristics

In order to reveals the Spatial Distribution Characteristics of actual evapotranspiration and driving factors. Based on MODIS data and meteorological data, the daily actual evapotranspiration of February and September 2001 is simulated by SEBAL remote sensing model in Dongjiang River. The space distribution rule of actual evapotranspiration is analyzed. The results show that actual evapotranspiration in north is more than that in south and west. Actual evapotranspiration of trees and water is most, the following is grass and broadleaf crop, the last is cereal crop and urban and built up. Actual evapotranspiration increases with elevation. Actual evapotranspiration is the most in east aspect in February. That is the most in southeast in September. It is smallest in flat ground, the following aspect is northwest in February and September. The relationship of actual evapotranspiration with land temperature, air temperature, albedo is negative, that with NDIV is positive. The relationship of actual evapotranspiration with sunlight rate is negative, that with precipitation is positive in February, it is opposite in September.