Welcome to the NavList Message Boards.


A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Compose Your Message

Add Images & Files
    Re: The taxonomy of refraction
    From: John Huth
    Date: 2011 Jan 7, 09:41 -0500
    Marcel - 

    I guess my first-order thinking is that the apparent horizon is going further out as the day progresses, and I can go back and test this against the theory, given the conditions.   But, the inferior image gave me pause.   I'll send them on to your expert as you suggest.


    John H. 

    On Fri, Jan 7, 2011 at 9:32 AM, Marcel Tschudin <marcel.e.tschudin@gmail.com> wrote:
    Uuups, I mixed up the temperatures John provided. If the water is
    colder than the air (and not the other way round) then it's unlikely
    to be an inferior mirage. I have therefore the same question as John
    has when he mentions "Nominally I associate this with the "hot road
    mirage", where the surface of a road is hotter than the air above it".
    The "hot road mirage" is actually the inferior mirage. I'm therefore
    also interested what Andy comments on it. Please let me know. I must
    admit that I'm not really familiar with these optical effects on
    distant landscapes since I observe the effects on the setting sun.
    It's the shape of the setting sun which informs me on larger
    temperature differences between sea and air and shows which is
    (considerably) warmer or colder.

    Keeping up with the grind
    Browse Files

    Drop Files


    What is NavList?

    Join NavList

    (please, no nicknames or handles)
    Do you want to receive all group messages by email?
    Yes No

    You can also join by posting. Your first on-topic post automatically makes you a member.

    Posting Code

    Enter the email address associated with your NavList messages. Your posting code will be emailed to you immediately.

    Email Settings

    Posting Code:

    Custom Index

    Start date: (yyyymm dd)
    End date: (yyyymm dd)

    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site