Water Cycle
The continuous movement of water between the Earth and its atmosphere.
Condensation
The change of state from a gas to a liquid.
Precipitation
Rain, snow, sleet, or hail that falls from clouds to the Earth's surface.
Percolation
The downward movement of water through soil and rock due to gravity.
Runoff
Water that flows across the land and enters rivers and streams. It eventually flows into lakes and the ocean.
Evaporation
Vaporization that occurs at the surface of a liquid below the liquid's boiling point.
Water Table
An underground boundary where the zone of aeration and the zone of saturation meet.
Transpiration
The water evaporates from the leaves of plants and moves into the air.
Watershed
The region of land drained by a river system.
Ground Water
The water beneath the Earth's surface.
Surface Water
Water at the surface of the earth.
Aquifer
A rock layer that stores ground water and allows it to flow.
Saturation
To soak or fill to the point where no more can be absorbed.
Permeability
A rock's ability to let water pass through it.