atmospheric pressure

noun, Meteorology
1.
the pressure exerted by the earth's atmosphere at any given point, being the product of the mass of the atmospheric column of the unit area above the given point and of the gravitational acceleration at the given point.
2.
a value of standard or normal atmospheric pressure, equivalent to the pressure exerted by a column of mercury 29.92 inches (760 mm) high, or 1013 millibars (101.3 kilopascals).
Also called barometric pressure.
Compare sea-level pressure.
Origin
1655-65
Examples from the web for atmospheric pressure
  • The outer envelope of all four sections contains air maintained at atmospheric pressure.
  • It runs at normal atmospheric pressure, and uses molten salts instead of water.
  • And since it operates at atmospheric pressure, the need for a costly containment dome is eliminated.
  • The blockage would cause a local rise of atmospheric pressure.
  • They're shock waves, created as the expanding fuel hits the higher atmospheric pressure outside the nozzle.
  • atmospheric pressure is the weight of the atmosphere overhead.
  • Changes in atmospheric pressure signal shifts in the weather.
  • As the balloon soared higher, the pressure inside stayed the same as the atmospheric pressure outside decreased.
  • atmospheric pressure increases the amount of energy needed to make water boil.
  • atmospheric pressure there is about half that at near-by sea level.
British Dictionary definitions for atmospheric pressure

atmospheric pressure

noun
1.
the pressure exerted by the atmosphere at the earth's surface. It has an average value of 1 atmosphere
atmospheric pressure in Science
atmospheric pressure
  (āt'mə-sfîr'ĭk)   
The pressure at any location on the Earth, caused by the weight of the column of air above it. At sea level, atmospheric pressure has an average value of one atmosphere and gradually decreases as altitude increases. Also called barometric pressure.

Our Living Language  : The weight of the air mass, or atmosphere, that envelopes Earth exerts pressure on all points of the planet's surface. Meteorologists use barometers to measure this atmospheric pressure (also called barometric pressure). At sea level the atmospheric pressure is approximately 1 kilogram per square centimeter (14.7 pounds per square inch), which will cause a column of mercury in a mercury barometer to rise 760 millimeters (30.4 inches). The pressure is frequently expressed in pascals, after the French mathematician and philosopher Blaise Pascal, who studied the transmission of pressure in confined fluids. Subtle variations in atmospheric pressure greatly affect the weather. Low pressure generally brings rain. In areas of low air pressure, the air is less dense and relatively warm, which causes it to rise. The expanding and rising air naturally cools, and the water vapor in the air condenses, forming clouds and the drops that fall as rain. In high pressure areas, conversely, the air is dense and relatively cool, which causes it to sink. The water vapor in the sinking air does not condense, leaving the skies sunny and clear.
atmospheric pressure in Culture

atmospheric pressure definition


The pressure caused by the weight of the air above a given point.

Note: Normal atmospheric pressure at sea level is about fifteen pounds per square inch. (See barometer.)