What is the atmospheric pressure in kpa?

Atmospheric pressure is about 101.325 kPa (kPa). ?

Standard atmospheric pressure. The unit used to express air pressure is the height of the mercury column. For example, a standard atmospheric pressure is equal to the weight of a 760 mm high mercury column, which is equivalent to an atmospheric pressure of 1.0336 kg on a square centimeter area. Since different countries use different units of weight and length, the units of air pressure are not uniform, which makes it difficult to conduct a comparative analysis of global air pressure. Therefore, it is internationally agreed to use "hundred Pascals" as the unit of air pressure.

After conversion, a standard atmospheric pressure = 1.013×105 Pa. 1 standard atmosphere = 760mm mercury (Hg) column height.

Influencing factors

The magnitude of air pressure is related to altitude, atmospheric temperature, atmospheric density, etc., and generally decreases exponentially as altitude increases. There are diurnal and annual variations in air pressure. During the year, the air pressure is higher in winter than in summer. During the day, the air pressure has a maximum value and a minimum value, which appear at 9 to 10 o'clock and 15 to 16 o'clock respectively. There is also a second highest value and a second low value, which appears at 21 to 22 o'clock and 3 to 4 o'clock respectively. .

The changes in air pressure are closely related to the quality of wind and weather, and are therefore important meteorological factors. Commonly used air pressure units include Pascal (Pa), millimeters of mercury column height (mm·Hg), and millibars (mb).

The conversion relationship between them is: 100 Pa = 1 millibar ≈ 3/4 mm mercury column height. Commonly used instruments for measuring air pressure in meteorological observations include mercury barometers, empty box barometers, and barometers. The pressure at the height of a vertical mercury column of 760 mm when the temperature is 0°C. The standard atmospheric pressure was first measured by Italian scientist Torricelli.