Ocean Circulation

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Ocean Circulation Chapter 1 1-18
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Latitude

• parallels
• angle from equator (0) to location
• North or South of the equator

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Longitude

• meridians
• angle from Prime Meridian (0) to location
• East or West of the Prime Meridian

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Glassboro, NJ 39 42 N, 75 07 W
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Questions

• Where does wind come from?
• Why do winds blow in the direction they do?

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Global air circulation

• How does the Coriolis effect drive the direction
  of these wind belts?

How does the Sun drive all of these wind patterns?
Note winds are named for where they come from
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Coriolis myth fact

• Myth water goes down the drain (or toilet)
  clockwise in the Northern Hemisphere and
  counter-clockwise in the Southern Hemisphere
• Fact hurricanes do rotate in different
  directions in the two hemispheres
• Counter-clockwise in N. Hemisphere
• Clockwise in S. Hemisphere
• Why?

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How does the Coriolis effect affect ocean
circulation?

• Winds drive waves currents
• Coriolis deflection of current directions
• (right in N. Hemisphere, left in S.
  Hemisphere)

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How does the Coriolis effect affect ocean
circulation?
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How does the Coriolis effect affect ocean
circulation?
Gulf Stream
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Ocean circulation from thermal density
differences
Cold, dense water sinks Warm, light water floats
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The ocean conveyor belt
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Upwelling

• When winds blow parallel to a shoreline
• and Coriolis deflection drives currents
  offshore
• Cold, nutrient-rich bottom water comes up to
  replace the displaced water along the coastline
• These are VERY PRODUCTIVE places

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Ekman spiral

• mass transport at 90 angle to wind direction
• direction of transport determined by Coriolis
  effect

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Equatorial upwelling
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Upwelling and primary productivity