Water that is held in rock, underground

When rain water soaks down into the ground

Water drops that fall to Earth as rain, hail, sleet, or snow

The process that turns water vapour into water

The process by which water runs over the ground into rivers

The process by which precipitation is stopped from reaching the ground surface by the presence of trees and other plants

The movement of water up plants and its subsequent loss as water vapour from their leaves

There is a fixed amount of water on Earth that neither increases nor decreases.

Humans need water for domestic, industrial and agricultural purposes.