صفحه 1:
002۸۵۱5
WATER, WATER EVERYWHERE...
BUT ONLY ON THE EARTH! |
صفحه 2:
Oceans
Over 70% of the Earth’s surface is covered
by water
Of that, 95% is salt water - only 5% is fresh
water - and part of that is ice
صفحه 3:
Ocean names
» All the oceans are really just one body of
water
» This is divided into the four named oceans:
1 Pacific
1 Atlantic
5 Indian
1 Arctic
صفحه 4:
Tides
» The oceans are always in motion
» Tides happen twice daily
» Tides are caused by the pull of gravity by
the moon, and to a lesser degree by the sun
» Why do you think the sun would pull less
than the moon?
صفحه 5:
Currents
» There are two type of Ocean Currents:
Surface Currents-Surface Circulation
» These waters make up about 10% of all the
water in the ocean.
» These waters are the upper 400 meters of
the ocean.
صفحه 6:
Currents
Deep Water Currents-Thermohaline
Circulation
< These waters make up the other 90% of the
ocean
» These waters move around the ocean basins
by density driven forces and gravity
» The density difference is caused by different
temperatures and salinity
» These deep waters sink into the deep ocean
basins at high latitudes where the
temperatures are cold enou
density to increase.
عا لمعب
صفحه 7:
Forces
» Ocean Currents are influenced by two types
of forces
» 1. Primary Forces--start the water
moving
» The primary
Solar Heatin
Winds
Gravity
صفحه 8:
Forces
» 2. Secondary Forces--influence where
the currents flow
» Surface Circulation
Solar heating cause water to expand. Near
the equator the water is about 8 centimeters
high than in middle latitudes. This cause a
very slight slope and water wants to flow
down the slope.
Winds blowing on the surface of the ocean
push the water. Friction o a
۲ wind and the water's surf
صفحه 9:
Wind direction
صفحه 10:
Wind
» A wind blowing for 10 hours across the
ocean will cause the surface waters to
flow at about 2% of the wind speed.
Water will pile up in the direction the wind
is blowing.
Gravity will pull the water down the "hill" or
pile of water.
But the Coriolis Force causes the water to
move to the right (in the northern
hemisphere) around the m
صفحه 11:
Mounding
ص2
صفحه 12:
» These large mounds of water and the flow
around them are called Gyres. The produce
large circular currents in all the ocean
basins.
> Gyres
صفحه 13:
» Remember the Coriolis Force move
objects to the right in the northern
hemisphere, and to the left in the
southern hemisy °
صفحه 14:
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