Validation of remotely sensed evapotranspiration: a case study

A comprehensive validation method of remotely sensed evapotranspiration (ET) was proposed in this paper. Among this method, an observation system was constituted of an eddy covariance system, a large aperture scintillometer and an automatic weather station, and then an observation network was established at Miyun, Guantao, Daxing, Xiaotangshan, and Haidian Park sites in Hai River Basin, which were set up from 2004 for ET and correlative parameters measurements at different satellite pixel scales. On this basis, rigorous data process and quality control were executed to ensure the high quality of observations. Meanwhile, a validation procedure of remotely sensed ET based on ground measurements was presented, and the method of selecting validation pixels and evaluation index were investigated intensively. According to this method, validation of remote sensing ET was performed in Beijing area. The results demonstrated the proposed validation method was feasible.