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The Water Cycle

    Going Round in Circles

RiverWater is constantly being cycled between the atmosphere, the ocean and the land. This cycling is a very important process that helps sustain life on Earth. When the sun heats water, the water evaporates or changes to water vapor. Water vapor rises and condenses or changes back into liquid water droplets. These water droplets are very small and form around dust particles.

    Falling for You
RiverWhen temperature conditions are right, these droplets gather together and form clouds. The clouds move over the land, and precipitation falls as rain, ice or snow. The water fills streams and rivers, and eventually flows back into the oceans where evaporation starts the process all over again!
    Soaking It All In
RiverSome of the water that falls on Earth goes through the process of infiltration. During infiltration, water is soaked into the ground. Some of this water returns to the Earth's surface and some of it remains underground and becomes groundwater. Plants absorb water from the soil. The water moves from the roots through the stems to the leaves. Once water reaches the leaves, some of it evaporates from the leaves, adding to the amount of water vapor in the air. This process of evaporation through plant leaves is called transpiration.
    Making Rain
RiverIn large forests, an enormous amount of water will transpire through leaves. In warm parts of the Earth, particularly near the Equator, plants create so much water vapor that they make their own weather! Rainforests rely on transpiration for most of their water.