From Glossary of Meteorology
One pascal (Pa) is equal to 1 newton m-2. The kilopascal (kPa) is the preferred unit for atmospheric pressure, but the more familiar millibar (mb) is the unit of pressure generally used by meteorologists, by international agreement; 1 mb = 1 hPa (hectopascal). For a typical sea level pressure, 102.345 kPa = 1023.45 hPa = 1023.45 mb.
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