Download Winds

Winds
Local Winds - Caused by changing air masses.
Sea Breezes
•Occur on warm sunny days.
•Air over the land heats faster than the air over the cool
ocean.
•Warmer air rises.
•Cool air flows in under it to fill the area over the land.
•This air warms and the cycle continues.
Land Breezes
•Occur at night and on cool days.
•Air over water maintains an even temperature.
•Air over land cools faster.
•Cooler air flows from the land out under the warmer
ocean air.
•This air warms and the cycle continues.
Changes in Pressure
•Air flows from high air pressure area toward a low
pressure area.
•High pressure usually brings clear weather.
•Low pressure usually brings stormy weather.
Changes in Temperature
•As air is heated by the sun, it begins to rise.
•Cool air flows in under it and takes it's place.
•This cycle is repeated continuously.
Global Winds - Caused by the earth's rotation ( Coriolis Effect)
and movement of warm air away from the equator.
Coriolis Effect: The earth's rotation causes air to move in a
circular motion.
Prevailing Westerlies
•When air moves toward the poles, it flows from west to east.
•The Prevailing Westerlies wind pattern causes most of the
weather changes in the United States.
Jet Stream
•A high-speed high-altitude airstream blowing from west to east
near the top of the troposphere.
•Has important effects of the formation of weather fronts.
El Nino - (El Nee-nyo)
•Warming of water in the Pacific Ocean.
•Rain and flooding along the Pacific coast
•Warm water disrupts food chain of fish, birds, and sea
mammals.
•Tornadoes and thunderstorms in southern US.
•Fewer than normal hurricanes n the Atlantic.
La Nina - (Lah Nee-Nyah)
•Cooling of water in the Pacific Ocean.
•Snow and rain on the west coast.
•Unusually cold weather in Alaska .
•Unusually warm weather in the rest of the USA.
•Drought n the southwest.
•Higher than normal number of hurricanes in the Atlantic.