What is evapotranspiration (ET)?

Evapotranspiration = evaporation (the movement of water, direct conversion of water into vapor, from the earth’s surface into the atmosphere) + transpiration (the vaporization of the liquid water contained in plant tissues. Water passes to the atmosphere through the stomata, organs that exist on leaves, and young stems and fruits).

These two natural procedures are described as one because of the simultaneous action.

In farming, evaporation is high on tilled fields because of the lower canopy density. Soil dries faster after plowing due to sun exposure and aeration. Transpiration depends on plant type, variety (drought-tolerant variety has lower transpiration), weather conditions, and agricultural practices.

Evapotranspiration is very important for defining the water needs of a crop and creating an irrigation schedule.