1. Atmospheric Circulation
Atmospheric circulation results from the differential heating of the earth
Heat is redistributed evenly over the globe
Redistribution occurs via circulation of air in the atmosphere
On a global scale, atmospheric circulation results from the differential heating of the planetary surface!!
-more heat equator – less heat poles
This situation is unstable and the heat must be redistributed more evenly over the globe!!
Redistribution of heat occurs via circulation of air in the atmosphere and circulation of water in the oceans!!

2. Tropical Heating Greatest heating at the equator Hot air
Rising air masses
Development of low pressure zones
Hot air
Less dense
Holds more moisture than cold air
Moist air is less dense than dry air at the same temperature and pressure
air with water vapor is less dense than dry air at the same temperature and pressure
when heated, air expands and becomes less dense, warm air holds more moisture than cold air
Net Effect - cold air is more dense than warm air, and cold, dry air is much more dense than warm, moist air!!
greater heating at the equator (i.e., tropics) results in rising air masses and the development of low pressure zones

3. At altitudes with equivalent ambient temperatures (and densities)
As air masses rise:
Temperature decreases
Water vapor cools and condenses
Rain and heat is released
At altitudes with equivalent ambient temperatures (and densities)
Air masses spread laterally
Move poleward and cool
Cooling air masses descend at poles
Creates high pressure
Air moves from high to low pressure
temperature decreases with altitude and water vapor in the rising air masses cools and condenses, resulting in rainfall and rainfall releases heat
air masses continue to rise, eventually reaching altitudes with equivalent ambient temperatures and therefore densities, air masses spread laterally (i.e., north and south)
at equivalent densities with the surrounding atmosphereair masses move poleward (either north or south of the equator) and cool
cooling air masses ultimately begin to descend, creating high pressure zones

4. Hadley cell

5. Doldrums
Trade winds
Horse latitudes
Prevailing westerlies
Polar easterlies

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