Global Winds What are they These are winds

Global Winds

What are they? • These are winds that are affected by the unequal heating of the earth’s surface. • Caused by regions of high pressure and lower pressure that form. • Differences in pressure and temperature set up a large system of winds around the globe.

Global Wind Systems: Doldrums – Located at the equator – Very warm air keeps the pressure very low – Winds are weak if any arise

Global Wind Systems: Trade Winds – Located between 0° - 30° North and South Latitude – Air from the equator cools and sinks – Air moves toward the equator – Produces warm steady winds

Global Wind Systems: Trade Winds (continued) Northern Hemisphere: Northeast Trades Southern Hemisphere: Southeast Trades 30° North or South = Horse Latitudes

Global Wind Systems: Prevailing Westerlies – Located between 40° - 60° in both hemispheres – Air from the equator moves toward the poles – It’s deflected east in both hemispheres – These winds are strong and constant

Global Wind Systems: Polar Easterlies – Located between 60° - 90° in both hemispheres – Cold air from the poles flows toward the equator – Winds are deflected west – Cold, weak winds

Jet Streams • High speed winds • Located at ~12 km in altitude • They can move north or south depending on other weather factors • Have a great impact on the daily weather.

Global winds and the Coriolis Effect • Global winds are affected by the Coriolis Effect • There is a shift in the winds due to the rotation of the earth. – Northern Hemisphere winds are shifted right – Southern Hemisphere winds are shifted left.