With Spring just around the corner, we’ve been thinking a lot about Earth’s water cycle. Feel free to share these fun facts with your students!
The Water Cycle is often thought of as a simple, cyclical process that often repeats itself. Most of us can remember being taught that water falls as rain, flows through rivers, streams, and lakes, ends up in the ocean, and is then evaporated back into clouds. It is often depicted like this:
The facts, however, are much more complex and interesting! First, remember that there are three different states of water:
1) solid ice
2) liquid water
3) gaseous evaporated water
Of all the water on the planet, about 97% of it is salt water. Of all the fresh water on the planet, nearly 70% is stored in ice-caps and glaciers, with nearly 30% stored in groundwater. That leaves just about 0.3 percent of all the fresh water on the planet to be found in surface lakes, rivers and streams!
Of course, those aren’t the only places that fresh water can be found; don’t forget about the water in animals, plants, clouds, and even the water used in agriculture and other human projects. This tells us that the water cycle is quite a bit more complex than what we might have thought.
The people at Project WET, an international team focused on water education, have set out to correct our misconceptions concerning the water cycle. They have created a wonderful array of lesson plans and teaching tools to be used in the classroom, including a wonderful dice game that does a great job mimicking the complexity of the water cycle. Check it out to dive deeper into this exploration of the water cycle!
National Geographic: http://www.nationalgeographic.org/media/earths-fresh-water/
Project WET: http://www.projectwet.org/
Project WET Sample Lesson Plan: http://files.dnr.state.mn.us/education_safety/education/project_wet/sample_activity.pdf