Evaporation
… Evaporation is a process that allows water to change from its liquid phase to a vapor.
… Hydrologists are mostly interested in the evaporation from the free water surface of open water or subsurface water exposed via the capillary action; however, precipitation that is intercepted by the vegetative canopy may also be evaporated and may be a significant amount in terms of the overall hydrologic budget.
… Factors that affect evaporation are temperature, humidity and vapor pressure, radiation, and wind speed.
… A number of equations are used to estimate evaporation. There are also a number of published tables and maps providing regional estimates of annual evaporation.