Estimation of evaporation using the surface energy balance system (SEBS) and numerical models

This study estimates evaporation using the Surface Energy Balance System (SEBS) method over an agricultural region in the Murrumbidgee Irrigation Area of NSW, Australia. Evaporation is estimated as latent heat flux using the standard Monin-Obukhov Similarity Theory (MOST) equations of SEBS and meteorological observations form an eddy-covariance system. Landsat and MODIS satellite data coincident with the period of in-situ flux measurements are used to examine the spatial variability of evaporation measurements. To extend the investigation, atmospheric forcing data from recent simulations of the Weather Research and Forecasting (WRF) model are used. A comparison at the point scale is made between observed eddy-covariance, modeled WRF predictions, and calculated SEBS values. In addition, the spatial variability of evaporation from the Landsat and MODIS images are compared against WRF results. Results show good estimation of the sensible heat flux using Landsat, MODIS, and WRF data, but estimation of the latent heat flux are not comparable with observations due to non-closure issues.