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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Dip and Temperature Gradient
From: Marcel Tschudin
Date: 2013 May 15, 02:09 +0300
From: Marcel Tschudin
Date: 2013 May 15, 02:09 +0300
Thank you, Paul, for locating and correcting here http://fer3.com/arc/m2.aspx/Dip-Temperature-Gradient-Hirose-may-2013-g24035 the wrong sign in my calculation of the temperature gradient, and for showing additionally how its value depends on the pressure difference. Thank you, Richard, for providing here http://fer3.com/arc/m2.aspx/Dip-Temperature-Gradient-Langley-may-2013-g24047 the two documents which also treat terrestrial refraction. I will have a look at them to find out what could be useful for my purposes. @Frank, Regarding refraction near the horizon: I was always astonished to see that it was considered sufficient to use during all seasons and at all times during the day the same set of (astronomical) refraction values as they were derived from some single standard atmosphere. I have the impression that it should be possible to attain improved estimates for some more specific "general" conditions. Marcel
