Shift in Magnetic North

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DrNed

The mountains are calling and I must go
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Thread starter #1
A Forbes article states that magnetic north
is constantly changing, approximately 7 miles a year, and the change lately has been 34 miles a year requiring an update in magnetic north.

As one who uses modern tech for navigation but always has a map and compass, I’m curious what this means in reality.
 

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#2
It means if you use a map and compass you need to make sure that you are adjusting declination based on the most current numbers. Don't rely on the declination on a map printed 10 years ago. As far as all the snazzy gps I believe it was a problem during the shutdown because some of the updates had not been made but I believe everything is good now.
 

Wyatt Carson

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#4
The poles also completely flip every so often, most likely not in our era but they have done it many times. Since I have lived here in southern Arizona the declination has changed around 3 degrees plus or minus. I simply get a new list of declinations every couple of years for the areas we ramble and list them in my notes.

Now if you find yourself afoot in the vast western wildernesses with no current declination you could follow Kephart’s advice on a clear night;

“The North Star bears exactly due north only twice a day. It is always close enough to steer by, but if one wishes to correct his compass by it he must

do so at a time when the double star in the middle of the Dipper's handle (c in the figure) is either directly above or directly below the North Star, for that is when the bearing is correct. At all other hours Polaris bears somewhat east or west of true north.”

Excerpt From
Camping and woodcraft; a handbook for vacation campers and for travelers in the wilderness
Kephart, Horace, 1862
 

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