Transcript Water on the Earth Notes

Water on the Earth
Notes
Earth Science
Grade 8
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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.
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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% Fresh water
33% of 3% = only
1% for all plants and
animals to use
97%
33%
available
to use
67%
locked in
glaciers
Fresh w ater in
glaciers
fresh w ater available
to use
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Water constantly moves through the atmosphere
by the water cycle.
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Water that does not soak into the ground or
evaporate into the atmosphere is called runoff.
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RUNOFF=RIVERS
Water Cycle Animation
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Click here
Four factors affecting absorption of
rain
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Amount of rainfall
Heavy downpour =
A lot of runoff
Light, misty rain=
Little run off
Four factors affecting absorption of
rain
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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
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Velocity of the Rivers
Fastest at 1) very center of the river
2)outside of the meander
2
1
Erosion/Deposition of a River
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Erosion occurs on the outside of the river meander
Deposition occurs on the inside of the river meander
Bed load and Suspended load
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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.
2.
3.
4.
Oxbow lake:
cutoff
meander