Download The Jet Stream and Ocean Currents

The Jet Stream and
Ocean Currents
Earth Science
Mr. Cloud
General
Circulation
in the
Troposphere
Prevailing Winds
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Winds that blow from a certain
compass direction for a large part of
the year
Affected by Earth’s rotation (Coriolis
Effect)
Otherwise known as planetary winds.
Example: prevailing westerlies
Monsoons
A wet day in Mumbai, India (summer monsoon)
In summer, the sun’s intensity
is greatest over Asia. This
creates a region of low
pressure that rises from the
land, sinks to the ocean, and
brings extreme moisture in its
return.
In winter, insolation has its
greatest intensity south of the
equator. This creates a region
of low pressure that rises from
the south, sinks over Asia, and
brings dry, cool weather to the
region.
Jet Streams are caused by extreme
pressure gradients between polar and
equatorial air masses.
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Jet streams follow the boundaries between hot and cold air.
The 50°-60° N/S region is where the polar jet is located
with the subtropical jet located around 30°N.
Temperature changes the greatest in these areas causing
extreme differences in air pressure.
As the difference in temperature between the two locations
increase, the strength of the wind increases
General Location of the Polar and Subtropical Jet
Stream in Summer (N. Hemisphere)
Surface Ocean Currents
What causes
Ocean Currents to flow?
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Break it down!
Earth is spherical
 causes uneven heating of the Earth
 causes convection in the troposphere
 establishes Earth’s pressure belts
 produces prevailing winds
 drags upon the ocean’s surface causing
the water to move!
Types of Ocean Currents
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Cold Current
originate in polar regions and flow
towards the equator
Warm current
originate in equatorial regions and
flow towards the poles
Ocean Currents: What
direction do they flow?
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Northern Hemisphere:
clockwise
Southern Hemisphere:
counterclockwise
Warm,
tropical
waters travel
in a
clockwise
direction due
to the
prevailing
winds and
Coriolis
Effect.
Color enhanced image of the Gulf Stream.