Global and Local Winds : Global and Local Winds
Air Movement : Air Movement Wind is the movement of air caused by differences in air pressure
The greater the difference, the faster the wind moves
Air Pressure : Air Pressure Differences in air pressure are caused by the uneven heating of Earth
Uneven heating produces pressure belts which occur every 30° latitude
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Pressure Belts : 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
Pressure Belts : 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
Global Winds : Global Winds The combination of pressure belts and the Coriolis Effect cause global winds
These are polar easterlies, westerlies, and trade winds
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Polar Easterlies : Polar Easterlies Wind belts that extend from the poles to 60° latitude
Formed from cold sinking air moving from the poles creating cold temperatures
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Westerlies : Westerlies Wind belts found between 30° and 60° latitude
Flow towards the poles from west to east carrying moist air over the Unites States
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Trade Winds : Trade Winds Winds that blow from 30° almost to the equator
Called the trade winds because of their use by early sailors
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Doldrums : Doldrums Located along the equator where no winds blow because the warm rising air creates and area of low pressure
Horse Latitudes : 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
Jet Stream : 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
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Local Winds : Local Winds Generally move short distances and can blow in any direction
Caused by geographic features that produce temperature differences
Sea Breezes : 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 breeze
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Land Breezes : 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
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Question 1 : Question 1 What causes winds?
Answer : Answer Winds are caused by the uneven heating of Earth’s surface, which causes pressure differences
Question 2 : Question 2 What are the three types of global winds?
Answer : Answer Polar Easterlies
Westerlies
Trade Winds
Question 3 : Question 3 What is the difference between a land breeze and a sea breeze?
Answer : 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