Exploring how forest restoration affects water cycles

How would afforestation and restoration of large areas worldwide affect water-fluxes world wide? A new study led by Wageningen University researcher Anne Hoek van Dijke with contributions from Martin Herold, GFZ, has ...

Lake evaporation patterns will shift with climate change

For many people, warm summer days feature spending time swimming in a lake. Lakes are important for more than just recreation and serve as a major global source of freshwater. But as temperatures continue to get warmer, so ...

Do forests lead to more or fewer clouds? It depends

Large-scale deforestation, forest restoration, forest fires, and droughts all have one thing in common: Most research on these topics focuses on forest ecosystems' impact on carbon storage and release. Other effects of forests ...

The curious task of watching liquid marbles dry

A comprehensive framework for studying the evaporation behavior of liquid marbles is helping KAUST researchers to better understand these tiny biological structures.

Researchers create morphing crystals powered by water evaporation

Water evaporation, as observed when a puddle of water disappears on a summer day, is a remarkably powerful process. If it were harnessed, the process could provide a clean source of energy to power mechanical machines and ...

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Evaporation is a type of vaporization of a liquid that occurs only on the surface of a liquid. The other type of vaporization is boiling, which, instead, occurs on the entire mass of the liquid.

On average, the molecules in a glass of water do not have enough heat energy to escape from the liquid. With sufficient heat, the liquid would turn into vapor quickly (see boiling point). When the molecules collide, they transfer energy to each other in varying degrees, based on how they collide. Sometimes the transfer is so one-sided for a molecule near the surface that it ends up with enough energy to 'escape' (evaporate).

Liquids that do not evaporate visibly at a given temperature in a given gas (e.g., cooking oil at room temperature) have molecules that do not tend to transfer energy to each other in a pattern sufficient to frequently give a molecule the heat energy necessary to turn into vapor. However, these liquids are evaporating. It is just that the process is much slower and thus significantly less visible.

Evaporation is an essential part of the water cycle. Solar energy drives evaporation of water from oceans, lakes, moisture in the soil, and other sources of water. In hydrology, evaporation and transpiration (which involves evaporation within plant stomata) are collectively termed evapotranspiration. Evaporation of water occurs when the surface of the liquid is exposed, allowing molecules to escape and form water vapor, this vapor can then rise up and form clouds.

This text uses material from Wikipedia, licensed under CC BY-SA