GEO 125

Physical Geography

Global Models:  Winds

Components of the wind regime

• Velocity

• Direction

• Duration

Vertical variation in winds

• Positive relationship between altitude and wind speed

• Headwinds versus tailwinds

• Negative relationship between altitude and turbulence

Factors infuencing the velocity  and direction of surface winds

• Velocity governed bypressure gradient force

• Direction governed by pressure gradient force, Coriolis effect, and friction

How winds are named

Prevailing versus dominant winds

Cyclonic versus anticyclonic wind circulation systems

Cyclonic wind circulation systems

• Associated with low pressure

• Counter clockwise in the northern hemisphere

• Clockwise in the southern hemisphere

Anticyclonic wind circulation

• Associated with high pressure

• Clockwise circulation in the northern hemisphere

• Counter clockwise circulation in the southern hemisphere

Global wind belts

• Northeast trade winds (northern hemisphere)

• Southeast trade winds (southern hemisphere)

• Prevailing westerlies ( northern and southern hemispheres)

• Polar easterlies (northern and southern hemispheres)

• Horse latitudes (northern hemisphere)

• Doldrums (Intertropical Convergence Zone or ITCZ)

Main Menu