Ocean Currents

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Ocean Currents
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Ocean Water Temperatures
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2 types of Ocean Currents

• Surface Currents stream-like movement of water
  that occur at or near the surface of the ocean.
• Deep Currents movements of water far below the
  surface.

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The paths of ocean currents are controlled by 3
factors

• 1. Global Winds
• 2. The Coriolis Effect
• 3. Continental Deflections

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1. Global Winds

• Winds that constantly blow in the same direction.
• When winds continuously blow across the surface
  of the ocean in the same direction, it causes the
  water underneath to head in that direction too.

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• Near the Equator, the winds blow ocean water from
  EAST to WEST (Trade Winds).
• This water is warm. After heading East to West,
  it begins to head toward the poles.
• Near the poles, winds blow from WEST to EAST
  (Prevailing Westerlies).
• Ocean water near the poles is cold.
• Global winds cause ocean currents to circulate
  between warm and cold water in a certain
  direction.

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2. The Coriolis Effect The curving of moving
objects from a straight path due to the Earths
rotation.

• Causes things to curve CLOCKWISE in the Northern
  Hemisphere.
• Causes things to curve COUNTER-CLOCKWISE in the
  Southern Hemisphere.
• Link http//ww2010.atmos.uiuc.edu/(Gh)/guides/mtr
  /fw/crls.rxml (kids with ball)
• http//www.nasa.gov/mov/142348main_corioliseffect_
  hi.mov (NASA)
• http//www.classzone.com/books/earth_science/terc/
  content/visualizations/es1904/es1904page01.cfm
  (on Earth)

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3. Continental Deflections

• If there were no continents at all (only water on
  Earth) the ocean currents would flow freely in
  very specific patterns.
• However, the continents that cover 1/3 the Earth
  get in the way and deflect, or change, the
  direction of the ocean currents.

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