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Evapotranspiration contributes water into the air - in the water cycle

Detailed Description

Evapotranspiration (Evaporation and transpiration)

Take a breath and breathe out—you just participated in the global water cycle. Your breath contains water—breathe on a glass pane to see it appear. When a person breathes, the term is called "respiration".

All the plants around you are "breathing" and releasing water, too. The term is called "transpiration", and although a Brussels sprout doesn't have a mouth, it has tiny holes in its leaves that allow water to leave the leaf, via evaporation, and go into the air. So, plants "transpire" water while humans "respire" water. A large tree can transpire many thousands of gallons during the growing season. 

But the big word is "Evapotranspiration", which is just a combination of "evaporation" plus "transpiration". This just means that not only are plants transpiring water from their leaves, water is evaporating from the soil all around them, too.


Public Domain.