Social Sciences and History / Unit 10 SSH 0929 short lesson, about 20 seconds
Where the Water Is; The Hydrologic Cycle
Captions available
The idea
Oceans hold ninety-seven percent of Earth's water; three percent is fresh, most of it ice in Greenland and Antarctica. A reservoir is any storage location, ocean, glacier, pond or atmosphere, and residence time is how long a molecule stays. The hydrologic cycle moves water among them.
In practice
Water expands when frozen.
Where people slip
Streams return land's rain to the sea.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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