Open Video Clip on Global Wind Patterns And High Low Pressure

Weather Map for Tuesday, April 17th

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

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

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.

Tradewinds— 0-30 degrees latitude at the equator (0 degrees), air rises, and then sinks at around 30 degrees north and south Westerlies— 30-60 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.

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

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

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

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

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