Winds & Pressure
Geography: AQA GCSE, topic 1.3.1
Winds and Pressure
Below are a few basics you need to understand before seeing the global atmospheric circulation model in full.
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What are winds?
- The wind is the movement of air on a large scale. The air is made up of gases.
What causes winds?
- Differences in air pressure cause winds.
What causes differences in air pressure?
- Like with convection currents, different temperatures cause movement.
- The equator is warmer than the North Pole or the South Pole.
- This difference causes different air pressures.
How does air pressure affect winds?
- Winds move from high-pressure areas of the Earth to lower-pressure areas of the Earth.
What are global atmospheric circulation cells?
- Winds combine to help create global atmospheric circulation cells.
- Global atmospheric circulation cells are made up of:
- Cool sinking air - forms high-pressure belts of wind.
- Warm rising air - forms low-pressure belts of wind.
- The Northern hemisphere has 3 global atmospheric circulation cells and the Southern hemisphere has 3 global atmospheric circulation cells.
- These cells are called the Hadley, Ferrel, and Polar cells.
Test yourself on Winds & Pressure
What do we call large scale movements of air?