Crop Evapotranspiration (ET) Estimation Models: A Review and Discussion of the Applicability and Limitations of ET Methods

摘要: This is a review paper on existing methodologies to calculate crop evapotranspiration (ETc). We have attempted present all the important ET estimation procedures date starting from simple empirical Blaney Criddle method complex Shuttleworth model. The common approach ETc estimate reference rate (ETref) using weather variables nearby station, and multiplying it by an appropriate coefficient (Kc). Recently, there been attempts actual (ETa) directly without Kc. latter still in developmental phase. study reviews literature identifies research needs current methods technology. extension of model for hourly time step validity Irmak Mutibwaa at field level various crops would be good milestone one estimation. Furthermore, are indications that development new variable canopy surface resistance (rc) model, which can applicable different climatic conditions, contribution this field.