Atmospheric Circulation

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Atmospheric Circulation

• Convergence Divergence Coriolis Force
  High Pressure Low Pressure
• What Does It All Mean???

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• Simple Model of Global Circulation
• Assumptions
• .
• The Earth is not rotating in space (no Coriolis
  Force)
• The Earth's surface is composed of similar
  materials (think of a flat astroturf world).
• But
• The global reception of solar insolation and
  loss of longwave radiation cause a temperature
  gradient of hotter air at the equator and colder
  air at the poles.

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If we let the earth rotate Planetary rotation
would cause the development of three circulation
cells in each hemisphere rather than one. These
three circulation cells are known as the Hadley
cell Ferrel cell and Polar cell.
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. Earth not rotating
Earth rotating
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• However The Earth's surface is not composed of
  uniform materials.
• The two surface materials that dominate are
  water and land. These two materials behave
  differently in terms of heating and cooling
  causing latitudinal pressure zones to be less
  uniform.
• Actual circulation patterns are also influenced
  by land elevation. Elevation tends to cause
  pressure centers to become intensified when
  altitude is increased. This is especially true of
  high pressure systems.

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Subtropical Jet Stream with
Surface Highs and Lows
Winter ?
Summer ?