1 / 12

15.4 air movement

15.4 air movement. The Water Cycle Continues. Learning Targets. List the properties of the air currents within a convection cell Describe how high and low pressure cells create local winds and explain how several types of local winds form

ulema
Télécharger la présentation

15.4 air movement

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. 15.4 air movement The Water Cycle Continues

  2. Learning Targets • List the properties of the air currents within a convection cell • Describe how high and low pressure cells create local winds and explain how several types of local winds form • Discuss how global convection cells lead to the global wind belts

  3. Air Movement • Caused by convection within Troposphere • Hot air rises • Less dense • Cold air sinks • More dense

  4. Pressure • High pressure H • Sinking air • Cold • Dry • Low pressure L • Rising air • Hot • Wet

  5. Low Pressure • Warmer air holds more moisture than colder air • When warm air rises and cools in low pressure zone, cannot hold all water it contains as vapor. • Excess water forms clouds and precipitation

  6. High Pressure • When cool air descends, it warms. Since it can then hold more moisture, the descending air will evaporate water on the ground

  7. Wind • Rules of wind • Moves from H to L • Moves from cold to hot • Named for direction it comes from • Local winds result from air moving between small H and L pressure systems • Global winds result from large H and L pressure systems

  8. Sea Breezes & Land Breezes • Local wind • Created by high specific heat of water and low specific heat of land • From sea to land in summer–Sea Breeze • Cool water; hot land • From land to sea in winter – Land Breeze • Warm water; cold land • Moderates coastal climates

  9. Global Wind Belts • 3 enormous convection cells • Control global climate zones • Hadley Cells 00 to 300 • Hot air rises at equator L • Ferrel Cells 300 to 500 • Separates Hadley and polar • Polar Cells 500 to 600 • Cold air falls at the poles H

  10. Global Wind Belts • Circulation cells determine amount of precipitation region receives • Low pressure regions: • air is rising • rain is common • High pressure regions: • Sinking air causes evaporation • Usually dry

More Related