What does the weather forecast say about air pressure and weather?

Some changes in atmospheric pressure are caused by storms, some by the circulation weather situation, and some by atmospheric molecules being forced to flow from a relatively high pressure area to a low pressure area in a certain horizontal area.

Most of the high-pressure and low-pressure belts shown on the weather map only form a mild breeze that accompanies us. However, the pressure difference required to generate the breeze only accounts for 1% of the atmospheric pressure itself, and this pressure change will occur in many areas. Relatively speaking, the formation of strong storms stems from the change of larger and more concentrated pressure areas.

Extended data:

Atmospheric pressure is related to altitude, atmospheric temperature and atmospheric density, and generally decreases exponentially with altitude. The air pressure changes every day and every year. In a year, the air pressure in winter is higher than that in summer. In a day, the air pressure has a maximum value and a minimum value, which appear at 9 ~ 10 and 15 ~ 16 respectively, and the second high value and the second low value appear at 2 1 ~ 22 and 3 ~ 4 respectively.

The daily variation of air pressure is small, generally 0. 1 ~ 0.4 kPa, and decreases with the increase of latitude. The change of air pressure is closely related to wind and weather, so it is an important meteorological factor. The commonly used units of air pressure are Pa, mmHg and millibar.

The conversion relationship between them is:100pa =1mbar ≈ 3/4 mm mercury column height. Commonly used instruments for measuring atmospheric pressure in meteorological observation include mercury barometer, empty box barometer and barometer. When the temperature is 0℃ and the pressure is 760mm, the standard atmospheric pressure is first measured by Italian scientist Torricelli.

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