The Earth’s The Earth’s WaterWater

Chapter 2 ~ Section 3Chapter 2 ~ Section 3

Oceans, lakes, rivers, and Oceans, lakes, rivers, and other bodies of water make up other bodies of water make up the earth’s the earth’s hydrospherehydrosphere

HydrosphereHydrosphere

HydrosphereHydrosphere

The total amount of water on The total amount of water on the earth does not change, but the earth does not change, but the water is constantly movingthe water is constantly moving

The The Water CycleWater Cycle shows the shows the regular movement of waterregular movement of water

http://www.classzone.com/books/earth_science/terc/content/visualizhttp://www.classzone.com/books/earth_science/terc/content/visualizations/es0105/es0105page01.cfm?chapter_no=visualizationations/es0105/es0105page01.cfm?chapter_no=visualization

The Water CycleThe Water Cycle

The Water CycleThe Water Cycle The sun The sun evaporatesevaporates the water from the water from

oceans, lakes, and streamsoceans, lakes, and streams Changes it from liquid to vapor, or gasChanges it from liquid to vapor, or gas Warm air carries more water vapor Warm air carries more water vapor

than cold airthan cold air

Excess vapor changes into liquid water Excess vapor changes into liquid water - - condensationcondensation

The Water CycleThe Water Cycle

Drops of water come together Drops of water come together to create cloudsto create clouds

When there is too much water When there is too much water in the clouds, it falls to the in the clouds, it falls to the earth as earth as precipitationprecipitation – rain, – rain, snow, or sleet depending on snow, or sleet depending on temperaturetemperature

The Water CycleThe Water Cycle

Bodies of WaterBodies of Water The earth is 70% waterThe earth is 70% water

almost all of it is salt wateralmost all of it is salt water

Four oceans: Four oceans: Pacific, Atlantic, Indian, and ArcticPacific, Atlantic, Indian, and Arctic

The Pacific Ocean is larger than all the The Pacific Ocean is larger than all the earth’s land combinedearth’s land combined

Seas, gulfs, and bays – smaller than Seas, gulfs, and bays – smaller than oceans & partially enclosed by landoceans & partially enclosed by land

97% of the earth’s water is salt water97% of the earth’s water is salt water

To make this water drinkable, it goes To make this water drinkable, it goes through the process of through the process of desalinationdesalination – removing the salt– removing the saltVery expensiveVery expensive

Bodies of WaterBodies of Water

Fresh waterFresh water3% of the earth’s water supply is 3% of the earth’s water supply is

fresh waterfresh waterMost of this is in glaciers and ice Most of this is in glaciers and ice

capscapsThe rest is found beneath the The rest is found beneath the

earth’s surface, in earth’s surface, in aquifersaquifers,, or in or in lakes & riverslakes & rivers