At sea level, the atmosphere exerts pressure on Earth at a force of 14.7 pounds per square inch.
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Courtesy of the FAA
is an idea scientists use to describe how gases and liquids "push" on things. The atmosphere
This pressure changes if you go different places on Earth. Imagine your home is very near sea level and that it is mild day (about 60oF).
If you go to a place that is high in the mountains, it will have less pressure then at your home. If it gets really, really cold at your house, there will be less pressure.
If a low pressure system passes over your house, the pressure will be less. If a high pressure system is passing over your house, that will make the pressure go up.
Atmospheric pressure is measured in many different ways.
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