Animation 1: The Water Cycle, Revisited

Now that you've had a chance to learn some vocabulary words, it's time to see them in action.

Watch this video to find out how human interference makes the REAL water cycle a lot more complex than the basic water cycle shown in the introduction.

As you're viewing the segment, look out for definitions and descriptions of glossary words. In addition to evaporation, condensation and precipitation, the terms interception, infiltration, and percolation will show up.

Stop the animation at any time, watch it again, or read the transcript.

Keyboard Shortcut	Action
Space	Pause/Play video playback
Enter	Pause/Play video playback
m	Mute/Unmute video volume
Up and Down arrows	Increase and decrease volume by 10%
Right and Left arrows	Seek forward or backward by 5 seconds
0-9	Fast seek to x% of the video.
f	Enter or exit fullscreen. (Note: To exit fullscreen in flash press the Esc key.
c	Press c to toggle captions on or off

Water Cycle Revisited Transcript

The water cycle may seem pretty simple. Water goes up due to evaporation and transpiration, water condenses, and then comes down as precipitation. But there are a few more steps to consider.

When water falls onto surfaces, it’s “intercepted” by things like leaves, trees, rocks and any surface (umbrella/sidewalk) that gets wet, but then dries (back to evaporation).

The water that does make it to the surface has two options, it can flow over the land as run off or it soaks in -a process called infiltration- and then percolates or moves through the soil. If it doesn’t get routed back into the “up” part of the cycle (trees taking up water, evaporation) it will likely make its way to a storage area like an underground aquifer, a lake or ocean.

But there is that one pesky detail that adds more complexity– humans. We like to change the environment which changes the flow of water through that environment. We build dams, cut down forests, and construct buildings. We divert water to crops (irrigation) and take water from the ground (extraction). All of which adds another arrow until it becomes less of a “cycle”, and more of a super complex system that is constantly changing and being changed.

Just another day in our wonderful, watery world.

Take Notes

1. Describe one possible path water can take after it falls to the ground as precipitation.
2. List three ways people change the flow of water through the water cycle

(Click SAVE when you have finished. To see your saved or submitted work again, click MY WORK at the top of the page.)