EVAPORATION
Evaporation is the process where a liquid in this case water changes from its liquid state to a gaseous state. Liquid water becomes water vapor. Although lower air pressure helps promote evaporation and temperature is the primary factor. The water vapor or steam leaves the river, lake, or ocean and goes into the air. For example, all of the water in a pot left on a table will eventually evaporate. It may take several weeks. But, if the pot of water is put on a stove and brought to a boiling temperature, the water will evaporate more quicly.
Approximately 80 percent of all evaporation is from the oceans, with the remaining 20 percent from inland and vegetation.