Transpiration is the process in which a plant releases water vapor from its leaves into the surrounding air. The rate transpiration occurs varies widely based on the weather and soil conditions surrounding the plant.
Transpiration occurs after a plant absorbs water from the soil through its roots. The water then travels into the leaves and stems. After absorbing its needed moisture and nutrients, the plant expels the excess water into the air. Humidity, temperature and several other factors determine how quickly transpiration occurs. An estimated 10 percent of the moisture in the atmosphere comes from transpiration, while the other 90 percent comes from oceans, lakes and other bodies of water.