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Re: Anomalous dip. was: [NAV-L] Testing pocket sextant.

From: Alexandre E Eremenko (no email)
Date: Fri Jun 16 2006 - 12:07:04 EDT

  • Next message: Bill: "Re: Anomalous dip. was: [NAV-L] Testing pocket sextant."

    Dear George,

    > We have to be careful about naming it "positive" or
    > otherwise. Usually, dip is a value that you have to subtract

    I follow the convention of the almanac tables.
    The negative sign there indicates that you subtract:-)

    But I agree to call it "reversed dip" to avoid confusion.

    > There can be misunderstandings here, also.

    Yes, I expected this too.

    > Normally, with increasing
    > height, the air temperature falls.

    I thought this was not the case in the lower layer over a sea surface
    I was confused by your example of a desert where sand
    is hot and air is cool. I always thought that it is this
    combination which gives reversed dip.
    (You do not even have to go to the desert, just look
    along a long, straight highway on a hot day. You will see
    a strong reversed dip).

    I thought that the combination of hot air and cold water
    would give the opposite effect. That is normal dip.

    But maybe I misunderstood something.
    Have to read some article on the subject...

    Now I depart to my sailing trip to Denmark,
    hope the weather will permit some Cel Nav:-)

    A


  • Next message: Bill: "Re: Anomalous dip. was: [NAV-L] Testing pocket sextant."



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