How is atmospheric pressure measured?

Atmospheric pressure is primarily measured in millibars (mb), a unit that reflects the pressure exerted by the weight of air in the atmosphere. One millibar is equal to 100 pascals, making it a commonly used unit in meteorology for reporting and comparing pressure readings.

Millibars are convenient for identifying significant weather patterns, as standard atmospheric pressure at sea level is approximately 1013.25 mb. Meteorologists use millibars to analyze high and low-pressure systems, advancing forecasts and understanding weather phenomena such as storms and hurricanes.

The alternatives provided do not appropriately measure atmospheric pressure. Pascals, although a valid unit for pressure, are not as commonly used in the meteorological context compared to millibars. Degrees Celsius is a unit of temperature, which is unrelated to atmospheric pressure. Liters per square meter is not a unit of pressure at all; it describes a volume over an area, making it unsuitable for measuring atmospheric pressure. Thus, the use of millibars as a standard unit in meteorology makes it the correct choice for measuring atmospheric pressure.