Evaluating the Performance of Various Evaporation Estimation Method Using Satellite Images over Saline Water Body (Case study: Urmia Lake)

Evaporation is one of the main sources of water loss. Various methods were introduced to estimate evaporation and evaluating their performances in saline water bodies is of great significant. Accordingly, the aim of this study was to use the remote sensing images in evaporation estimation models applied to a saline water body and evaluate the results. Accordingly, using Moderate Resolution Imaging Spectroradiometer (MODIS) images and meteorological data, evaporation from the Urmia Lake was calculated by employing FAO56-PM, Priestley-Taylor, Kimberly-Penman, Hargreaves-Samani, and METRIC methods and the spatial distribution of evaporation was mapped. The result of this research showed that the evaporation is not evenly distributed over the selected saline water surface and considering a constant value of albedo for the whole surface would result in an error in the evaporation estimation. The obtained result indicated that combined methods give more reliable results compared to the other methods since they consider all effective parameters.