Search results
Results From The WOW.Com Content Network
Map showing atmospheric pressure in mbar or hPa A tire-pressure gauge displaying bar (outside) and pounds per square inch (inside) Atmospheric air pressure where standard atmospheric pressure is defined as 1013.25 mbar, 101.325 kPa, 1.01325 bar, which is about 14.7 pounds per square inch.
Atmospheric pressure, also known as air pressure or barometric pressure (after the barometer), is the pressure within the atmosphere of Earth.The standard atmosphere (symbol: atm) is a unit of pressure defined as 101,325 Pa (1,013.25 hPa), which is equivalent to 1,013.25 millibars, [1] 760 mm Hg, 29.9212 inches Hg, or 14.696 psi. [2]
Deutsche Seewarte atmospheric pressure map 23 January 1907. Maximum pressure in Europe 22–23 January 1907 recorded in Pärnu, Estonia and Riga, Latvia at 1067.1 mbar. [3] The Free University of Berlin state the European air pressure record is 23 January 1907 in Riga at 1068.7 hPa. [4]
On the top right corner of the model for a surface weather map is the pressure, showing the last two integer digits of the pressure in millibars, or hectopascals, along with the first decimal. For instance, if the pressure at a certain location is 999.7 hPa, the pressure portion of the station model will read 997.
A millibar is a way of measuring pressure. The lower the pressure, the more powerful the storm. Some of the most intense winter storms to batter the country's coasts have been bomb cyclones.
A prognostic chart is a map displaying the likely weather forecast for a future time. Such charts generated by atmospheric models as output from numerical weather prediction and contain a variety of information such as temperature , wind , precipitation and weather fronts .
Such maps have been in use since the mid-19th century and are used for research and weather forecasting purposes. Maps using isotherms show temperature gradients, [2] which can help locate weather fronts. Isotach maps, analyzing lines of equal wind speed, [3] on a constant pressure surface of 300 or 250 hPa show where the jet stream is located.
The ambient atmospheric pressure at sea level is not constant: it varies with the weather, but averages around 100 kPa. In fields such as meteorology and underwater diving, it is common to see ambient pressure expressed in bar or millibar. One bar is 100 kPa or approximately ambient pressure at sea level.