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    Anomalous atmospheric conditions and Dip correction?
    From: Tony Oz
    Date: 2021 Sep 6, 04:42 -0700


    Quite often there are conditions (at 60°N 30°E) that are not handled by "usual" refraction correction tables.

    This happens when the cold air is above much warmer water, and some sort of miraging appears. In less severe form - the line of sight bends upward hiding low objects on the horizon that are usually visible.

    I have two questions here:

    • how does this atmospheric condition affect the refraction at higher angles? Say, the angles more than 15°?
    • is this line of sight bending equivalent to the additional Dip, HoE change or me being further off from an observed body?

    Is it correct to say that such a bending (cold air above warm water) makes apparent Earth "more round" (i.e. of less equatorial radius)? And the opposite condition (warm air above cold water) makes Earth "flatter"?

    I need a way to understand these aspects to be able to quickly judge what the error in my intercept will be - will I be "away" or will I be "toward" - to compensate for this offset.

    Warm regards,
    60°N 30°E

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