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    Re: Ah, give someone a calculator.......
    From: Gary LaPook
    Date: 2010 Aug 15, 19:50 +0200

    I'm just trying to figure out how you would measure 8000 SM visibility.
    The distance to the horizon is calculated with the formula of 1.35 times
    the square root of the height above the sea which gives you the distance
    in statute miles (from table 12 in Bowditch.) The highest point on earth
    is Mt. Everest at 29,035 feet above sea level. Applyiung the formula,
    the distance to the sea horizon from the top of Mt. Everest (assuming no
    intervening obstructions) is 230 SM. Even assuming another mountain as
    high as Mt. Everest existed and that the two were separated by an
    unobstructed sea horizon, the maximum distance that you could see
    between these peaks is twice as much, 460 SM so it appears the maximum
    visibility that could ever be measured on the surface of the earth is
    only 460 SM, much less that the 8000 SM given in the Weather Underground
    weather report.
    Giving it some  more thought, since the maximum diameter of the earth is
    only 7926 SM, to be able to measure 8000 SM you would need to drill a
    hole through the center and out the opposite side and then have a
    satellite fly over the opposite opening at an altitude of 74 SM and
    shine a powerful light down through the hole so that you can see it from
    your side.
    Marcel Tschudin wrote:
    > Trying here different settings:
    > I don't get the language mixture as you seem to have. All is shown in
    > English, my selected language, because the translations are bad. The
    > value for the visibility is definitely wrong. Regarding the pressure:
    > When I started to use to use their archived data, I had first some
    > difficulties to find out what the "strange" values around 30 would
    > correspond to.
    > Marcel

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