Global and local winds
- 1. Global and Local Winds
- 2. Air Movement •Wind is the movement of air caused by differences in air pressure •The greater the difference, the faster the wind moves
- 3. Air Pressure •Differences in air pressure are caused by the uneven heating of Earth •Uneven heating produces pressure belts which occur every 30° latitude
- 5. Pressure Belts •As warm air rises at the equator and moves toward the poles, it cools •As it cools, some of the air sinks around 30° north and south of the equator
- 6. Pressure Belts •At the poles, cold air sinks and moves towards the equator •Around 60° north and south, the air begins to heat up and rise
- 7. Global Winds •The combination of pressure belts and the Coriolis Effect cause global winds •These are polar easterlies, westerlies, and trade winds
- 9. Polar Easterlies •Wind belts that extend from the poles to 60° latitude •Formed from cold sinking air moving from the poles creating cold temperatures
- 11. Westerlies •Wind belts found between 30° and 60° latitude •Flow towards the poles from west to east carrying moist air over the Unites States
- 13. Trade Winds •Winds that blow from 30° almost to the equator •Called the trade winds because of their use by early sailors
- 15. Doldrums •Located along the equator where no winds blow because the warm rising air creates and area of low pressure
- 16. Horse Latitudes • Occur at about 30° north and south of the equator where the winds are very weak • Most deserts on the Earth are located here because of the dry air
- 17. Jet Stream •The jet streams are narrow belts of high speed winds that blow in the upper troposphere and lower stratosphere •Separates warm air from cold air
- 19. Local Winds •Generally move short distances and can blow in any direction •Caused by geographic features that produce temperature differences
- 20. Sea Breezes • High pressure is created over the ocean during the day and low pressure over land due to uneven heating • Air moves from the ocean to the land creating a sea
- 22. Land Breezes • Low pressure occurs over the ocean during the night and high pressure over land due to the uneven heating of earth • This causes wind to move from the land to the ocean creating a land breeze
- 24. Question 1 •What causes winds?
- 25. Answer •Winds are caused by the uneven heating of Earth’s surface, which causes pressure differences
- 26. Question 2 •What are the three types of global winds?
- 28. Question 3 •What is the difference between a land breeze and a sea breeze?
- 29. Answer •Sea breezes occur during the day when the land is warmer than water and a land breeze occurs at night when the water is warmer than land