XI. Wind

A. Global circulation cells (fig. 18.15)
warm air rises, cold air sinks
  1. equatorial low (doldrums,ITCZ)
  2. sub-tropical high; (horse latitudes)
  3. sub-polar low
  4. polar high
  5. seasonal variations (fig. 18.16)
B. Pressure Basics
  1. pressure (focus on horizontal variations)
  2. isobars
  3. pressure gradient
C. Controls on wind speed and direction
  1. pressure gradient - high to low pressure (perpendicular to isobars)
  2. coriolis effect (fig. 18.6)
  3. surface friction
D. Global winds
  1. polar easterlies
  2. westerlies
  3. trade winds
  4. doldrums (intertropical convergence)
E. Regional variations (fig 18.10)
  1. cyclone - Low in center, ccw, convergent, cloudy
  2. anticlyclone - High in center, cw, divergent, fair skies
F. Local winds
  1. land/sea breeze - fig. 18.17
  2. mountain/valley breeze - fig. 18.18
  3. monsoon
  4. El nino - fig. 18.21, 18.22
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