Chapter 7: Atmospheric Circulations

Scales of atmospheric motionEddies of different sizes

Microscale- chimney smoke, leaves in a corner of a building

Mesoscale- city smoke, a sea breeze/land breeze Synoptic scale- weather fronts, winter storm

Local Wind Systems

Thermal Circulations Sea breeze Land breeze

Seasonal winds Santa Ana winds

• Warm dry, fall season winds

The monsoon• Seasonal reversal in winds• Wet summer/Dry winter• Most pronounced in Asia• Does occur in Southwest U.S.

Mountain/Valley Breezes

Valley Breezes Mountain slopes heat up Air rises along the mountain slopes Upslope valley breezes Clouds may form along mountains At night, slopes begin to cool Air along slopes sinks into the valleys Colder air settles into valleys

Desert winds

Hot desert air Haboobs Dust devils Dust storms

These wind storms are quite common in the deserts….

Focus on “Readings”

Eddies and “Air Pockets”Snow Eaters and Rapid Temperature Changes

Global Winds

Intertropical Convergence Zone (ITCZ) Equatorial low pressure, rising air Doldrums

Sub tropical high pressure zones 30° Horse Latitudes Sinking air

Westerlies Jet stream winds

Polar easterlies Sinking air

Polar Jet Stream

North PacificHigh Pressure

Equatorial Low Pressure

Polar Jet Stream

Pacific High

End of Chapter 7

Key TermsQuestions for Review: 1, 4, 5a-b, 6, 7, 8, 9a-b, 10, 11, 12, 13, 14, 15, 16, 17, 18a-c, 19, 20, 22.

Questions for Thought/Exploration 7, 9, 10,