Validation and Comparison of Seven Land Surface Evapotranspiration Products in the Haihe River Basin, China

Evapotranspiration (ET) is an important part of the surface energy balance and water balance. Due to imperfect model parameterizations forcing data, there are still great uncertainties concerning ET products. The validation land products has a certain research significance. In this study, two direct methods, including latent heat flux (LE) from towers method method, one indirect three-corned hat (TCH) uncertainty analysis, were used validate compare seven types in Haihe River Basin China. evaluated included six based on remotely-sensed observations (surface global evapotranspiration [EB-ET], Moderate Resolution Imaging Spectroradiometer [MODIS] terrestrial product [MOD16], Penman–Monteith–Leuning version 2 [PML_V2], Global Land Surface Satellite [GLASS], evaporation Amsterdam [GLEAM], Zhangke [ZK-ET]) atmospheric re-analysis data (Japanese 55-year re-analysis, JRA-55). goals study provide reference for Basin. results indicate following: (1) have higher accuracy when used. Except MOD16_ET EB_ET, Pearson correlation coefficients (R) all greater than 0.6. root mean square deviation (RMSD) values less 40 W/m2. GLASS_ET smallest average (BIAS) value. Overall, GLEAM_ET accuracy. (2) When approach was used, low overestimated high underestimated. GLEAM_ET, JRA_ET, PML_ET, ZK_ET overestimated. According seasonal variations statistics, most R spring lower summer, RMSD highest summer. (3) quantification TCH value relative lowest. JRA_ET mountainous areas non-mountainous area, PML_ET areas. performances relatively equal. significantly summer other periods, they also varied different sub-basins.