Normal atmospheric pressure varies, but is usually around 14.7 lbs per square inch (psi).
If a liquid has a vapor pressure of greater than atmospheric pressure, that liquid boils.
For example, when you heat a pan of water the vapor pressure increases until it reaches atmospheric pressure.
Returning the superheated mixture suddenly to atmospheric pressure causes it to separate into its liquid and gaseous components.
At higher altitudes, where atmospheric pressure is lower, oxygen enters the body less readily, leading to the hypoxic state.
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Atmospheric pressure is caused by the weight of the air over our heads.
The chamber is pressurized with pure oxygen, and the pressure inside the chamber will slowly rise to about two and a half times normal atmospheric pressure.
Temperature increases were found to increase the chances of people developing severe headaches, and low atmospheric pressure, which usually causes cloudy, stormy weather, can have a smaller effect.
Though he devoted much spare time to tracking atmospheric pressure with a portable barometer, by age 50 he had stopped writing scientific papers and instead occupied himself with obscure religious controversies.
Chronic hypobaric hypoxia (lack of oxygen): where the expedition will encounter equivalent altitudes up around 3, 800m due to the extreme cold temperatures and distance from the Equator which further decreases atmospheric pressure.
This is the height of tornado season across much of the American Midwest, when the changing seasons bring that peculiar mix of moisture, hot and cold temperatures and varying atmospheric pressure that creates a funnel of death.
The flooding, which began on the night of 31 January, was caused by a combination of a high spring tide, deep atmospheric low pressure which raised sea levels and exceptionally strong northerly gales, which led to a surge of sea water over coastal defences.
Then in the early 20th Century, German chemist Fritz Haber invented a high temperature-high pressure technique to convert atmospheric nitrogen into ammonia.
At the bottom of the Knotty Head hole, the 450-degree-Fahrenheit temperature and the pressure (2, 000 times atmospheric) would crush or melt most drilling tools.
Researchers using the car-sized mobile laboratory have identified transient whirlwinds, mapped winds in relation to slopes, tracked daily and seasonal changes in air pressure, and linked rhythmic changes in radiation to daily atmospheric changes.
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