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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Earth's Magnetic Pole Shifting
From: Frank Reed CT
Date: 2005 Dec 9, 20:51 EST
From: Frank Reed CT
Date: 2005 Dec 9, 20:51 EST
Andrew C, you wrote: "I found this on AP Science today. It is interesting, and I am sure that this will affect our estimated position and compass work in the next several decades. I am not sure how we factor this in, and am wondering if anyone has observed this effect in their work. http://news.yahoo.com/s/ap/20051209/ap_on_sc/earth_magnetic_pole " It's not too difficult to include this in navigational calculations. Although the pole is moving along at a faster than average clip right now, it is not historically unusual. It's believed that the north magnetic pole was in about the same latitude as today some 450 years ago. From year to year (up to a decade or so), the change in the magnetic field at any given locality can be accounted for by a simple linear increase or decrease in the magnetic variation (or magnetic "declination" as most everyone except mariners call it). On a time scale of decades, it's not so simple. The article you reference makes a very good point about the aurorae. The area that sees the northern lights most often lies in a roughly circular band centered on the north magnetic pole. As the pole rockets north, that band follows. That means fewer opportunities to see the aurora borealis in the northern USA. By the way, the south magnetic pole's motion is no symmetrical with the north at all. The south magnetic pole is still a long way from the geographic south pole. Just evidence of the fact that the Earth's field is much more complex than the simple dipole field of a bar magnet. The magnetic poles are not directly opposite each other, and they do not move in synchrony. -FER 42.0N 87.7W, or 41.4N 72.1W. www.HistoricalAtlas.com/lunars
