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Global warming may affect the moisture content of soil, subsequently affecting plant productivity. This is all the more so in deserts where water is the major limiting factor. In an attempt to evaluate the possible effect of temperature rise on pan and soil evaporation, the evaporation rates of water from variable-size pans and of plots of variable degree of shading (all with different water/soil temperatures) were compared. A close link between the water temperature of the pan (resulting from the different diameter-size pans) and class A pan evaporation was found. The data showed that an increase of 1 degrees C in the maximum temperatures implied an increase of 0.08 mm/day, i.e. similar to 8.3% in the evaporation rate of the pan. Similarly, an increase in the subsurface temperatures (at 5 cm depth) substantially decreased the available water content at the 0- to 10-cm soil, with the evaporation rate increasing by 0.07 mm/day (similar to 6.6%) for each 1 degrees C increase in soil temperature. The findings suggest an increase of similar to 10% in the evaporation rate of the soil surface for each 1 degrees C increase in soil temperature. The advantage in estimating the possible effect of temperature rise upon soil evaporation via shaded plots in comparison with the classical approach of soil heating is discussed, as well as the possible effect of temperature rise on biocrusts, seedling germination and plant productivity. Copyright (C) 2015 John Wiley & Sons, Ltd.