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    Re: Extremely poor conditions??
    From: Brendan Kinch
    Date: 2012 Mar 20, 18:54 +0100

    In follow on from the below quote and maybe more relevant if you say it was
    hot that day.....
    Sub refraction may occur,
    "In warm moist air over the sea when an increase in humidity with height may
    occur. In this case a temperature inversion will usually accompany the
    humidity inversion, but when the humidity factor is dominant sub-refraction
    will result. These conditions may sometimes be found in the warm sector of a
    depression in temperate latitudes"
    I do not know the whole weather picture during the time you were taking
    sights and am aware that the mariners handbook is written with conditions at
    sea the governing factor (rather than at the shore) - but if you are still
    in a puzzle then any hint as to a possible reason for what you experienced
    will give you food for thought.
    -----Original Message-----
    From: navlist-bounce@fer3.com [mailto:navlist-bounce@fer3.com] On
    Behalf Of Alexandre E Eremenko
    Sent: 20 March 2012 16:59
    To: NavList@fer3.com
    Subject: [NavList] Re: Extremely poor conditions??
    > What you describe here is Sub Refraction as opposed to Super refraction.
    > Sub refraction (is upward bending) and as per Mariners Handbook:  "can
    > occur when cool air flows over a relatively warmer sea"
    Which is exactly opposite to the conditions that apparently existed.
    However, I suspect it could be relevant that we observed from the shore.
    It was really hot, and the sand on which we stood was warm, then the sea is
    shallow near the shore...

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