Geography Notes

In: Business and Management

Submitted By mwuestho
Words 681
Pages 3
February 25, 2013

Winds Aloft
* Isobaric surfaces slope downward from the low latitudes to the pole
* Atmosphere is warmer near the Equator, pressure gradients force pushes air poleward
* Pressure gradient force increase with altitude, bringing strong winds at high altitudes
* Friction increases from low latitude to high latitude
* Decreases in upper atmosphere where wind speeds are high

The Geostrophic Wind
* At high latitudes, a moving parcel of air is subjected to: Pressure gradient force and Coriolis forces.
* When forces balance, air moves at right angles to the pressure gradient, parallel to the isobars, as the geostrophic wind
* Winds that move bulk of our air mass around the planet
* Heavy lifting of moving heat

Global Circulation at Upper Levels
* General pattern global circulation at upper levels
* Bands of equatorial easterly winds (result of downward air)
* Bring air into the equator
* Found at higher latitudes
* Tropical high-pressure belts
* Zone of westerly winds – come from est and blow to east
* Polar lows
* Lack of land mass and lack of friction fast winds speeds in southern hemisphere

Jet Streams and the Polar Front
* Jet streams are streams of fast-moving air at high altitudes that occur where atmospheric temperature gradients are strong
* Each hemisphere normally exhibits westerly polar and subtropical jet streams.
* An easterly jet occurs in summer over Asia and Africa
* Polar jet located between 35 and 65 latitude in both hemispheres
* Boundary between cold polar air and warm subtropical air
* Altitudes of 10 to 12 km (about 30,000 to 40,000 ft)

Disturbances in the Jet Stream
* Broad wavelike undulations called Jetstream disturbances or Rossby waves
* Occurs from heating and cooling
* The flow of…...