World Geography / Unit 2: Physical Geography
2.5 Earth's Water
Notes
About 71 percent of Earth's surface is covered by water, and most of it is salty ocean. Only about 3 percent of Earth's water is fresh, and most of that is frozen in glaciers and ice sheets.
- The water cycle: evaporation, condensation, precipitation, then runoff or infiltration back to oceans.
- A watershed (drainage basin) is all the land that drains into one river system.
- Groundwater is stored in underground layers called aquifers.
- Five oceans: Pacific (largest), Atlantic, Indian, Southern, Arctic. Seven continents: Asia (largest), Africa, North America, South America, Antarctica, Europe, Australia/Oceania.
- Ocean currents move heat. Warm currents (Gulf Stream) raise coastal temperatures; cold currents (Humboldt, off South America) cool them.
Practice
Which is the largest ocean?
The Pacific covers about one-third of Earth's surface.
Where is most of Earth's fresh water stored?
Most fresh water is locked up as ice, mainly in Antarctica and Greenland.
The land area from which all the rain and snowmelt flows into one river is called its
A watershed or drainage basin feeds a river system.
Ready for more? Take the Unit 2 test.