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    Re: The taxonomy of refraction
    From: John Huth
    Date: 2011 Jan 9, 09:16 -0500
    Marcel - 

    If you know of a website that has that information, that would be great.   The town is Harwich Port, MA, US

    The approx midpoint of a line from the lighthouse to my house is

    41 deg 37 min  N 70 deg 03 min W

    I think it was Aug. 10th - I have to look it up.  I do know how to get the sea surface temperature - there is a lot of buoy data that the US NOAA site has recorded.   This is typically the most reliable for me.


    John H. 

    On Sat, Jan 8, 2011 at 7:46 PM, Marcel Tschudin <marcel.e.tschudin@gmail.com> wrote:
    Thank you, John, for sharing the answer.

    Yes, the question regarding the wind is important in this case, since
    the image shows the opposite of what one could conclude from the air
    and water temperatures. An other point could be how deep the water
    temperature has been measured. I also could imagine a thin layer of
    cold air on top of the water which didn't mix with the warmer air
    above it.

    More information on the temperature profile of the atmosphere could be
    found from a sounding of a nearby radiosonde station. One could
    possibly also find some further information on the sea surface
    temperature (SST). Do you know how to retrieve such data? If not, let
    me know date, time and location, I can give it a try.

    At my location I observe these days also inferior mirages when the sun
    is setting. In December we had for about a week or ten days a warm
    periode with temperatures about 10C higher than average which heated
    the water. Now having again colder temperatures the inferior mirages
    show up. On January 1st I happened to catch a nice one which I attach
    here. (I notice that my lens needs some cleaning.)


    Keeping up with the grind
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