Water cycle

The water cycle shows the continuous movement of water within the Earth and atmosphere. Liquid water evaporates into water vapor, condenses to form clouds, and precipitates back to earth in the form of rain and snow.

Clouds

Clouds form when the invisible water vapor in the air condenses into visible water droplets or ice crystals.

Condensation

The transition process from the vapor state to the liquid state is called condensation. The water droplets that form from this condensation make up clouds.

Evaporation

Evaporation is the transfer of water from the surface of the Earth to the atmosphere. Transpiration is the evaporation of water through minute pores, or stomata, in the leaves of plants.

Precipitation

By condensation, water vapor in the atmosphere is released to form precipitation. It can be in the form of rain, sleet, snow, or hail. Precipitation is always fresh water, as sea salt does not evaporate.

Runoff

Runoff is the quantity of water discharged in surface streams. This happens when there is more water than the land can absorb. Rivers and lakes are the results of runoffs.

Groundwater

Groundwater is the water found underground in the cracks and spaces in soil, sand, and rock. It is stored and moves slowly through geologic formations of soil, sand, and rocks called aquifers.