1. Open Video Clip on Global Wind Patterns
And High Low Pressure

2. Weather Map for Tuesday, April 17th

4. WIND
Is air in motion
Is caused by the uneven heating of the earth’s surface by the sun

5. Warm air which weighs less than cold air, rises
Warm air which weighs less than cold air, rises. Cool air moves in and replaces the rising warm air
High to Low Video Clip
COOL AIR
WARM AIR
High pressures are cool air; low pressures are warm air
Winds blow from a high pressure to a low pressure
Winds are named by the direction they blow from

6. DIFFERENT TYPES OF WIND PATTERNS
1. JET STREAM: narrow belts of strong winds found in the lower stratosphere
Video Clip on
Global Winds…3 min
2. GLOBAL WIND PATTERNS: These are winds that are happening in the upper atmosphere ALL THE TIME. These patterns are made because hot air (low pressure) rises and cold air (high pressure) sinks.

7. Tradewinds— 0-30 degrees latitude
at the equator (0 degrees), air rises, and then sinks at around 30 degrees north and south
Westerlies— degrees latitude
Air sinks at 30 degrees north and south and rises again at 60 degrees north and south
Are responsible for moving weather across the U.S.

8. Polar Easterlies— 60-90 degrees latitude
Air rises at 60 degrees north and south, and then sinks at the poles
Doldrums
are found at the equator and are weak winds.
Horse Latitudes
Found at about the 30° latitude over the oceans…weak winds here

9. 3. LOCAL BREEZES: occur because of the heating differences of land and water
SEA BREEZES—a convection current blows wind from the cooler sea towards warmer land during the day
Land warms up faster than water during the day
Wind blows from a high to a low (cold to warm)
Cool Air
Warm Air
Sea Breeze

10. LAND BREEZES occur at night, air moves toward the water as the land cools more rapidly than the water.
Water keeps its heat longer than land at night
Winds are named by the direction they blow from
Warm Air
Cool Air
Land Breeze

11. AMAZING EARTH SCIENCE FACTS
1. _______ are caused by the uneven heating of the earth
2. ______________ causes deflections of the atmosphere and oceans due to the rotation of the Earth
3. Winds blow from ________ pressure to _______ pressure
4. Cold air is ________ pressure because the molecules are close together and weight more than hot air
Winds
Coriolis effect
high
low
high

12. 5. Warm air is ______ pressure because the molecules are far apart, therefore weight less
6. U.S. weather is dominated by prevailing ____________. Weather moves west to east.
7. ______ breeze- daytime, land is hot (low pressure) ocean is cold (high pressure) winds blow high to low
8. _______ breeze-occurs at night and is the exact opposite of the conditions above
low
westerlies
Sea
Land