Barometric pressure of under 29.50 inches of mercury at sea level is considered low. At sea level, a normal barometer reading is between about 29.70 inches of mercury and 30.20 inches. More »

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Barometric pressure was discovered in about 1644 when physicist and inventor Evangelista Torricelli invented the first mercury barometer. Torricelli was an assistant to Galileo Galilei who suggested that Torricelli try u... More »

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A barometric pressure sensor measures pressure differences in the atmosphere. In automotive applications, this reading is used by the powertrain control module to regulate engine timing and fuel trim. More »

Barometric pressure was discovered in about 1644 when physicist and inventor Evangelista Torricelli invented the first mercury barometer. Torricelli was an assistant to Galileo Galilei who suggested that Torricelli try u... More »

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The normal air pressure at sea level is 14.7 pounds per square inch. Standard atmospheric pressure can also be expressed using different units, including 1013.25 millibars, 1013.25 hectoPascals, 760 millimeters of mercur... More »

Air pressure, the force exerted on a mass by the weight of air particles, is measured in either inches of mercury or in millibars, represented by inHg and mb, respectively. One standard atmosphere, represented by the sym... More »

Low barometric pressure is caused by warm air from the planet's surface rising, decreasing the amount of air pulled downward by Earth's gravity. This rising heat can lead to adverse weather conditions. More »