Earth’s Water

1. Earth’s Water 2.2 identify and locate major land masses and bodies of water

2. The Caspian Sea in southeastern Europe/southwestern Asia is actually a salt lake–the largest one on Earth. It is a lake, not a sea, because it is surrounded by land. The ancient Romans called the Caspian a sea because its water was salty. Australia’s Lake Eyre, Venezuela’s Lake Maracaibo, and Utah’s Great Salt Lake are other notable saltwater lakes

4. The Water Cycle • The part of the earth that is covered by water is called the hydrosphere. • Most of the hydrosphere is salt water, found in the oceans, seas, and some lakes. • The rest of the hydrosphere is the freshwater of lakes, rivers, and springs.

5. The sun’s heat evaporates water, which remains in the air until the air cools. • The cool air returns the water to Earth in the form of rain, snow, or sleet. • The total volume of the hydrosphere remains relatively constant because the evaporated water returns to Earth as precipitation.

7. Bodies of Salt Water Oceans • About 97 percent of the hydrosphere is a huge body of salt water divided into four oceans: the Atlantic, the Pacific, the Indian, and the Arctic Oceans.

8. Seas, Gulfs, and Bays • Large bodies of salt water partially enclosed by land comprise seas, gulfs, and bays.

9. Ocean Water to Drinking Water • Because of the great demand for drinking water, people are experimenting with desalination–the removal of salt from ocean water. 2.4 explain the significance of water as a renewable resource

11. Bodies of Freshwater • Only about 3 percent of the hydrosphere is freshwater, and most of it is frozen in glaciers and icecaps, inaccessible to people.

12. Lakes, Streams, and Rivers • A lake is a body of freshwater completely surrounded by land. Only a few lakes are made of salt water. • Streams are narrow bodies of water flowing through areas of land. Rivers are large streams that carry greater volumes of water.

13. Because rivers and streams flow through land, they carry freshwater to people and animals. • Most people and animals live near sources of freshwater.

14. Groundwater • Ground water is freshwater lying beneath the planet’s surface. • Natural springs and handmade wells allow people to retrieve groundwater.