Pressure Readings on Surface Weather Maps

What does a reading of 894 of pressure on a surface weather map represent?

A. Atmospheric pressure of 894 millibars

Answer:

The reading of 894 on a surface weather map represents the atmospheric pressure directly at the surface level, without adjustment for elevation.

When interpreting a surface weather map, the pressure value shown is the atmospheric pressure at the site of measurement. However, it is important to note that this reading may not reflect the actual atmospheric pressure at sea level. As altitude increases, atmospheric pressure decreases.

To account for this variation in elevation, meteorologists employ a method known as "reducing to sea level," which adjusts the measured pressure value based on the height of the measurement location.

In this case, the reading of 894 on the surface weather map specifically signifies the atmospheric pressure at the surface, uncorrected for elevation. Therefore, the correct interpretation is that it represents a pressure of 894 millibars.

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