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    Re: Ups and Downs of reflecting AH's
    From: David Iwancio
    Date: 2022 Aug 4, 14:29 -0700

    Loz:

    For the swirling water, are you sure there's no breeze getting into your glass tent?  If there's a draft pushing at the edge of your plate it could cause the swirling.  Maybe put a feather or something similarly light in there to see if it's disturbed.

    As for refraction in your immediate environment, tables and mathematical models of refraction assume that the air being looked through is "well mixed," with any "lumps" evened out.  Being surrounded by tall, wind-blocking buildings keeps the air from being mixed very well (you might have noticed that mirages are associated with little to no wind being present).  There's also the wider "heat island" effect that comes from living in an urban area, which has you looking up through nested domes rather than flat layers.  As for how much this might change things, I don't know.

       
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