Water on the Earth Notes Earth Science Grade 8

The Earth is the only planet in the solar system to be covered in water. Water covers about 75% of the Earth’s surface. Any place on the Earth that contains water is called the hydrosphere.

Of the water on the Earth, 97% is salt water and 3% is fresh. Almost 67% of all the fresh water is locked up in glaciers near the North and South Poles. That leaves just 1% of all the water on the planet available for plants and animals to live on.

Water Percentages 3% 33% of 3% = only 1% for all plants and animals to use 97% 33% available to use 67% locked in glaciers

Water constantly moves through the atmosphere by the water cycle. Water that does not soak into the ground or evaporate into the atmosphere is called runoff. RUNOFF=RIVERS

Water Cycle Animation http://epa.gov/climatechange/kids/water_cycle_version2.html

Four factors affecting absorption of rain Amount of rainfall Heavy downpour = A lot of runoff Light, misty rain= Little run off

Four factors affecting absorption of rain Time span of the rain 2 inches of rain in 1 hour = a lot of runoff 2 inches of rain in 1 week = little runoff

***Four factors affecting absorption of rain Slope of the land Steeper the land, the more run off Flatter the land, less runoff

****Four factors affecting absorption of rain Amount of vegetation Lots of vegetation = less run off No vegetation= more off

Velocity of the Rivers Fastest at 1) very center of the river 2)outside of the meander 2 1

Erosion/Deposition of a River Erosion occurs on the outside of the river meander Deposition occurs on the inside of the river meander

Bed load and Suspended load Bed load: material that rolls along the bottom of the river Suspended load: material that floats suspended in the water

Development of an Oxbow lake 1. Oxbow lake: cutoff meander 2. 3. 4.