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    Re: Table A4 + elevation?
    From: Paul Hirose
    Date: 2003 May 2, 09:53 -0700

    George Huxtable wrote:
    > Vaguely remembering (or maybe misremembering?) the density (relative to
    > water) of air as 1/830 and of Mercury as 13.6, it seems to me that at
    > Doug's height of 2100 ft. the atmospheric pressure will be reduced by 7.5%
    > below what it is at ground level. (Somebody please check!) If that's
    > correct, then the local pressure will reduce to 935 millibars, compared
    > with its "standard" sea-level value of 1010. That takes it well outside the
    > realms of the diagram that goes with table A4, which goes no further down
    > than 970.
    At 2100 feet in the 1976 U.S. Standard Atmosphere, pressure is .92641
    of sea level. Multiplying that by 1010 mb gives 935.7 mb. Pretty good
    estimate, George.

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