Estimation of Annual Change of Actual Catchment Evapotranspiration Using Landsat TM Data and Complementary Relationship Equation

the Case of Tokoro River Basin

Abstract

Land cover classification in Tokoro river basin was done immediately after cutting out the catchment image from the Landsat TM full-and sub-scene so as to superimpose this image on an elevation mesh image. The monthly mean Evapotranspiration (ET) of Tokoro river basin was obtained by Kojima's equation in winter and by Morton's equation in other seasons. The annual change in estimated monthly mean ET, which reaches its maximum value in July, increases as the albedo decrease. The influence of land cover category, land development and air temperature on ET was examined.