Estimation of lake evaporation from standard meteorological measurements: application to four Australian lakes in different climatic regions

A simple net heat model is presented for estimating monthly lake (or reservoir) evaporation using the Penman formulation with standard meteorological data: air and water-surface temperature, relative humidity, wind speed and sunshine hours. The model comprises simple expressions for the net solar and terrestrial radiation fluxes, or the net all-wave flux, at the waterʹs surface, and for heat storage. The model is applied to four Australian lakes in semi-arid tropical, warm temperate, mediterranean and alpine climatic regions. The model predictions are found to agree well with mean monthly evaporation measurements for the four lakes. The net heat model was used with the Priestley- Taylor formulation, which does not require wind measurements, and its predictions were found to also agree well with the observations.