The semi-empirical Priestley-Taylor (PT) approach was originally developed to monitor monthly evapotranspiration (ET) at a 1 km resolution at a continental and global scale, by integrating satellite data from Moderate Resolution Imaging Spectroradiometer (MODIS) and AmeriFlux tower measurements (Jin et al., 2011). We have adapted the PT method for high spatial resolution ET estimates by using Landsat satellite data. This automated remote sensing (RS) data-driven approach has a potential to estimate more accurate ET by model calibration and multi-satellites data fusion in a cost efficient way.