Meteorology · Pressure — Units and Conversion
A barometric pressure of 1013.25 millibars (hPa) is equal to approximately:
- A14.7 inches of mercury
- B29.92 inches of mercury (the standard atmosphere)✓ Correct
- C1013 inches of mercury
- D76 inches of mercury
Explanation
The standard sea-level atmosphere is 1013.25 mb (hPa) = 29.92 inches of mercury = 760 mm Hg. Mariners convert between millibars and inches when comparing instruments; 1 inch Hg ≈ 33.86 mb.
Authority: WMO; Bowditch (Pub. No. 9)
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