Impact of spatial scale on remotely sensed evapotranspiration estimates from heterogeneous land surfaces

Abstract

Remote sensing can provide estimates of spatially distributed actual evapotranspiration (ET) at different spatial scales. Methods that combine remotely sensed observations with other ground-based information on land and atmospheric properties usually allow improved estimates of spatially distributed evapotranspiration (ET) than when remotely sensed data are used alone. Spatial resolution of remotely sensed ET estimates depends on the specifications of the satellite instruments (e.g., 60 m for Landsat, 1 km for MODIS and 10 km for AVHRR). Since satellite sensors have different spatial, spectral and radiometric resolutions, it is essential to understand the consistency of ET estimates from dif..