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Re: magnetic variation calculator
From: Bill Murdoch
Date: 2005 Feb 24, 20:02 EST
From: Bill Murdoch
Date: 2005 Feb 24, 20:02 EST
In a message dated 2/24/05 7:18:09 P.M. Eastern Standard Time,
george@HUXTABLE.U-NET.COM writes:
I'm puzzled. Bill implies that there was no change in variation with
longitude? (Both locations showing variation of -3.797 deg, though 1 degree
apart in longitude?). Was that what he meant to write?
You are right George. I got the numbers wrong. For a one degree
change in longitude at my location the declination changes from -3.797 to -3.029
or about 3/4 of a degree.
Of course it was tongue in cheek. It is pure happenstance that I
have a significant change of declination with latitude at my
location. And, the measurement of azimuth at sea to the required accuracy
would be difficult at best. And, I wonder about the accuracy of the model
(A mountain called Iron Mountain is just to the east of me.). And, no
doubt it has taken a couple of centuries of data gathering to support the
model.
But, it is fun to play.
Bill Murdoch
