This paper presents a new formulation which connects the variations in evaporation among adjacent shallow saline solutions to the differences in their surface temperatures. The derivations are based on the theory of water vapor transfer and energy balance considerations. Evaporation differences among adjacent shallow saline solutions are evaluated without the need to measure their activity coefficients or the prevailing meteorological forcings. The only parameters needed to evaluate the differences in evaporation among saline solutions exposed to the same meteorological forcings are their surface temperatures and a general heat transfer coefficient term for sensible heat. When combined with conventional or remote-sensing data, the procedure can be used for operational purposes and as a diagnostic tool to analyze evaporation and heat balance dynamics of saline water bodies under different environmental conditions. The present formulation will prove useful in evaluating the transfer coefficient of sensible heat using only evaporation from and temperature of saline solutions having different activity coefficients. In addition to the above applications this formulation can be extended to examine the efficiency of monolayers or other chemicals in suppressing evaporation from freshwater lakes, particularly in arid and semiarid regions. This can be achieved by observing the increase in temperature of these water bodies compared to untreated or controlled dams or lakes.