Some Discussions on the Algorithms for Estimating Evapotranspiration for Mixed Landscapes in Three-Temperature Model

Three-temperature model (3T model) was a recently proposed algorithm, which could be used to estimate actual evapotranspiration (ET) and evaluate environmental quality. The 3T model has been verified as a simple and accurate one for soil evaporation and vegetation transpiration in situ. It also showed a good potential to estimate ET accurately under regional or macro scale conditions for the mixed-landscape. However, because the algorithm for estimating ET in the 3T model was only proposed from theoretical deduction, several parameters need to be further defined and the accuracy of algorithm needs to be verified. Therefore, the aim of this paper is to define and verify an algorithm for estimating ET for the mixed landscapes. By revising the original algorithm in the 3T model, new algorithm was proposed. The validation results showed that the revised algorithm was much better than the original one.