Understanding the Water Cycle: A Comprehensive Guide

1. The Water Cycle

2. INDEX • Water Background • The Water Cycle • Evaporation • Condensation • Precipitation • Collection • Review • Content Standards • References

3. Water Background • Pure water is colorless. It often appears blue in ice or in a clear lake or green or brown in a river because it contains or reflects other matter. • Over 97 percent of the earth’s water is found in the ocean as salt water. • Two percent of the earth’s water is stored as fresh water in glaciers, ice caps, and snowy mountain ranges. • The one percent left remaining is used for our daily water supply needs. Index

4. The Water Cycle Condensation Precipitation Evaporation Collection Index

5. The sun heats up water in rivers, lakes or ocean and turns it into vapor or steam. The water vapor or steam leaves the river, lake or ocean and goes into the air. Index

6. As Water Vapor in the air gets cold, it changes back into liquid forming clouds. Index

7. This occurs when so much water has condensed that the air cannot hold it anymore. The clouds get heavy and water falls back to the earth in the form of rain, hail or snow. Index

8. When water falls back to earth as precipitation, it is then collected back in the oceans, lakes or rivers or it may end up on the land as groundwater. Then the cycle start all over again. Index

9. Now, Let’s review the four stages of the Water Cycle. Evaporation is when the sun heats up water in rivers or lakes or the ocean and turns it into vapor or steam. The water vapor or steam leaves the river, lake or ocean and goes into the air. Index

10. Water vapor in the air gets cold and changes back into liquid, forming clouds. This is called condensation. Index

11. Precipitation occurs when so much water has condensed that the air cannot hold it anymore. The clouds get heavy and water falls back to the earth in the form of rain, hail, sleet or snow. Index

12. Collection is when water falls back to earth as precipitation. It may fall back in the oceans, lakes or rivers or it may end up on land.  When it ends up on land, it will either soak into the earth and become part of the “ground water” that plants and animals use to drink or it may run over the soil and collect in the oceans, lakes or rivers where, guess what, the cycle starts all over again. Index

13. References ACWA Water Education Foundation Kidzone Index

14. California State Board of Education Content Standards met: Grade Five Earth Sciences Content Standards Water on Earth moves between the oceans and land through the processes of evaporation and condensation. As a basis for understanding this concept: 3a Students know most of Earth's water is present as salt water in the oceans, which cover most of Earth's surface. 3b Students know when liquid water evaporates, it turns into water vapor in the air and can reappear as a liquid when cooled or as a solid if cooled below the freezing point of water. 3c Students know water vapor in the air moves from one place to another and can form fog or clouds, which are tiny droplets of water or ice, and can fall to Earth as rain, hail, sleet, or snow. Index