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This image shows three common ways that atmospheric pressure is measured - using a mercurial barometer, an aneroid barometer or a barograph.
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Windows Original (Using images from FAA)

Measuring Atmospheric Pressure

Even though we can't see air, it is real and pushes on the things it surrounds. The push of the atmosphere is called pressure. Atmospheric pressure changes all the time.

We can measure the pressure of the atmosphere with a mercury barometer or with an aneroid barometer. You can see they look very different in the picture to the left. Both of the instruments will tell us if the pressure has gone up or gone down.

If a mercury barometer or an aneroid barometer is set up to take measurements all the time, it is called a barograph (see picture).

Nowadays, many weather instruments like the mercury barometer or an aneroid barometer have been replaced by electronic instruments that record atmospheric pressure onto a computer.

Atmospheric pressure can be measured in many different units. Some of the units are called Pascals, bars, or even inches of Mercury. They are all used in describing and forecasting Earth's weather.

Last modified June 11, 2010 by Becca Hatheway.

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