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Re: Magnetic Variation
From: Jeremy C
Date: 2010 Feb 27, 22:21 EST
From: Jeremy C
Date: 2010 Feb 27, 22:21 EST
No, if you read the chart, it will give you an "annual change" of
Variation, not a seasonal variation. For example, the chart will say
variation 0 deg, annual change 6' E. If the chart edition was 2000,
by 2010 the variation should be 1 degree East. There is no noted cycle
over the course of a year, otherwise there would be a table on the chart for
each month.
Jeremy
In a message dated 2/27/2010 9:45:18 P.M. Eastern Standard Time,
apacherunner@gmail.com writes:
Do you mean that variation on charts etc is updated annually or there is a component to the variation that has a year-long periodicity?
The first I can easily believe - the second doesn't seem right.
On Sat, Feb 27, 2010 at 9:30 PM, <Anabasis75@aol.com> wrote:
I've never heard of that at all. Variation has to do with the magnetic fields of the earth. While they may change slightly with the Earths angle and distance to the sun over the course of a year, it certainly isn't something that you deal with in practical navigation. Variation, as marked on charts, changes annually, and usually only by some matter of minutes.I guess it depends a lot on exactly how technical you want to be with this.JeremyIn a message dated 2/27/2010 9:22:42 P.M. Eastern Standard Time, guyschwartz@sbcglobal.net writes:Hello all:
I just took a test today and one of the questions had to do with magnetic variation. The answer to the question was that magnetic variation changed seasonally. I checked Chapman’s, Dutton’s and Bowditch, no mention of seasonally adjusting?
Anyone have any information or was the test wrong?
Thanks
Guy
"May the SCHWARTZ BE WITH YOU"