Evaluation of Energy Balance, Combination, and Complementary schemes for estimation of evaporation

A comparison between three basic approaches for estimation of actual evapotranspiration, namely, the energy balance, the combination, and the complementary approaches is undertaken. We utilized Monin- Obukhov Similarity Theory (MOST) as a framework for the energy balance method, the single-layer Penman-Monteith method as the combination approach, and the Advection-Aridity method as the complementary approach, in a sound analytical framework. Data from 3 flux tower stations are used to evaluate model estimated heat fluxes at short time steps. Results indicate advantages and/or limitations of each method under different conditions, highlighting issues in application of the Advection-Aridity technique in dry conditions and energy balance methods over sparse canopies.