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    Re: Refraction at the horizon.
    From: Marcel Tschudin
    Date: 2008 Mar 19, 11:20 +0200

    ... when I wrote last night the above comment related to the powers of
    temperature and pressure I should have added that I don't understand
    (yet) the reason for it. I therefore can't absolutely exclude an
    artefact of the calculation itself. However, thanks to Andrew T. Young
    the program could be tested beforehand carefully on several less and
    more critical bench mark calculations. The more critical cases were
    situations just at the edge before ducting occurs and situations with
    ducting, this for different observer positions. The results compared
    well. We found that the (small) differences we had resulted mainly
    from calculating/using gravity slightly different when calculating the
    pressure for the different layers. Andy used one same gravity value
    for all layers, calculated for an intermediate hight of the atmosphere
    (which is for his simulations absolutely sufficient) whereas in my
    model the gravity is calculated for an intermediate height within each
    When I dug again in the files which were produced one year ago I
    selected "a" set of available graphs without finding out whether they
    really corresponded to the latest results found at that time. The aim
    was to show you what I meant with exponential behaviour, not more.
    It's clear that it would be interesting to understand the reason for
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