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The Water Cycle

Water plays many different roles on the Earth. Some is at the poles in ice caps, and some is in the snow and glaciers at the tops of high mountains. Some is in lakes and streams, and some is underground. Some is vapor in the atmosphere. But most of the water on Earth is in the oceans.

Water is always on the move! The Sun’s energy causes water to evaporate from oceans and lakes into the atmosphere. Plants and animals also release water vapor into the atmosphere as they breathe. When the atmosphere cools, water vapor condenses; making clouds that might produce rain or snow. Water has been recycled in its different forms as ice, liquid, or vapor --for more than 3.5 billion years.