Nile River Basin Evaporation in Average Year

The evaporation maps show the clear divide from the moist highlands of central and eastern Africa to the arid desert area. Evaporation is higher in the moist regions and low in the desert area. Despite high temperatures in arid regions there is little available water so evaporation estimates are very low. In contrast the Ethiopian highlands experience lower temperatures which results in less rainfall being evaporation and more to appear as run off. It is interesting that the main stem of the river does appear to have slightly higher evaporation than the surrounding areas.