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Old 09-02-2011, 13:20   #16
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Right here: "The pole kept going during the 20th century, north at an average speed of 10 km per year, lately accelerating "to 40 km per year," says Newitt. At this rate it will exit North America and reach Siberia in a few decades."

Earth's Inconstant Magnetic Field - NASA Science

Unfortunately, the term "magnetic north pole shift" in Google brings up a lot of apocalyptic nutjob stuff concerned with the lights going out and Jesus's return according to the Mayan calendar being hampered thereby.

Good grief.

EDIT: Here's a brief, more current explanation: http://openintelligence.amplify.com/...-to-core-flux/
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Old 06-03-2011, 21:18   #17
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Re: Variation Getting More Variable

My god. that means the Russians will have control of it. If they turn it off we'll all be lost. Hows that for some nutjob paranoia?
I think we are quite capable of adapting but I think the annual deviation on our current charts may be out of sync with the real variation. I don't know what it would cost to update them if it had to be done at shorter intervals.
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Old 06-03-2011, 21:51   #18
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Re: Variation Getting More Variable

Quote:
Originally Posted by perchance View Post
My god. that means the Russians will have control of it. If they turn it off we'll all be lost. Hows that for some nutjob paranoia?
I think we are quite capable of adapting but I think the annual deviation on our current charts may be out of sync with the real variation. I don't know what it would cost to update them if it had to be done at shorter intervals.
Goto post 13, it's free. or here; NOAA's Geophysical Data Center - Geomagnetic Online Calculator
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Old 07-03-2011, 08:37   #19
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Re: Variation Getting More Variable

Unless my small motors start failing, I'm OK with this!
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Old 07-03-2011, 09:10   #20
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Re: Variation Getting More Variable

Computation of magnetic variation for any given location is apparently an inexact science.

My NOAA chart for Washington, DC harbor has a compass rose which notes that variation in 2010 is 10 degs 45 mins Westerly, with a yearly change rate of 0 degs 1 minute.

If you use NOAA's Geophysical Data Center computer to calculate the variation for the same location for the year 2010 you get 9 degs 28 mins Westerly, also with a yearly change rate of 0 degs 1 minute.

That's more than one degree of difference!!

Navigator beware :-)

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Old 07-03-2011, 09:27   #21
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pirate Re: Variation Getting More Variable

Damn.... so thats why I'm sleeping so poorly lately...
My Feng Shui is outa sync.... gotta move the damn bed again
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