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WEATHER
Lesson 3 - Page 3

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In the area of higher pressure the air molecules are closer together than in areas of lower pressure. Warm air, which is lighter, cause low pressure. Air that is warmed exerts less pressure on the ground creating a low pressure region. Cold air when it is over the oceans will actually depress the sea level in that area. Warm air will elevate the sea level.

Cold air is denser and heavier and pushes the warmer, lighter air upward. Depending on how the warmer air is pushed will depend upon how big the "fight" will be. Where these two air masses meet is called a "front." How these different fronts meet cause weather patterns to change. Remember there are many temperature variations of "cold" air and "warm" air, resulting in many weather types.


Moving from low to high pressure  
causes movement


Warm front

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