Is the local atmospheric pressure greater than, equal to or less than 1 standard atmospheric pressure?

It is possible that the local atmospheric pressure is greater than, equal to or less than 1 standard atmospheric pressure. Different areas have different altitudes and different air pressures. Standard atmospheric pressure is the air pressure at sea level under standard atmospheric conditions.

standard atmospheric pressure was put forward by physicist Torricelli in 1644, and its value is 11.325kPa, which is the unit of pressure and is recorded as atm.

once in chemistry, the standard temperature and pressure (STP) were defined as °C(273.15K k) and 11.325kPa(1atm), but in 1982, IUPAC redefined the standard pressure as 1 kPa.

1 standard atmospheric pressure =76mm Hg =76cm Hg = 1.1325× 1 5pa = 1.339 m H2O.

Extended data:

The change of atmospheric pressure is related to altitude. Atmospheric pressure is produced by the action of gravity in the atmosphere. The higher the ground is, the thinner the atmosphere is, and the smaller the atmospheric pressure there should be. However, because the air density related to the gravity received by the atmosphere varies unevenly with height, the atmospheric pressure decreases unevenly with height. Variation with height: the atmospheric pressure decreases with the increase of height.

the change of atmospheric pressure is also related to the weather. At different times, the atmospheric pressure in the same place is not exactly the same. We know that the density of water vapor is smaller than that of air. When there is more water vapor in the air, the air density will become smaller and the atmospheric pressure will also decrease.

changes with climate: in general, the atmospheric pressure is higher in sunny days than in cloudy days, higher in winter than in summer, and higher in the morning than at noon.

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