Abstract: Evapotranspiration is a key factor which frequently used in the agricultural and meteorological change studies.However it is difficult to estimate evapotranspiration(ET) over large area of natural land surface.In this study,the evapotranspiration estimation models with vegetation cover and bare soil were presented based on information of surface parameters like vegetation fraction and surface albedo.Combined with vegetation fraction data,a model for regional evapotranspiration estimation over the heterogeneous landscape was derived from Landsat TM/ETM+.Meanwhile,through a case study with remote sensing data in Quanzhou city,which lies in Southeast China,the accuracy of the model for regional evapotranspiration estimation was validated.The features of evapotranspiration in Quanzhou City and models were also discussed.It is possible to estimate the regional evapotranspiration by this model.

Key words: Evapotranspiration, Evapotranspiration, Remote sensing, Heterogeneous landscape, Quanzhou city