Re: KRS: Final thoughts on North Pole

On Sun, 03 Jul 2005 15:35:39 GMT, Philip Deitiker
<Donevenask@xxxxxxxxxxxxxxx> wrote:

>"Daryl Krupa" <icycalmca@xxxxxxxxx> says in
>news:1120365321.271411.292090@xxxxxxxxxxxxxxxxxxxxxxxxxxxx:
>
>> You seem to be using the same term "magnetic pole" for
>> two different concepts: the North Magnetic Pole (NMP),
>> towards which a compass needle points, and the Geomagnetic
>> North Pole (GNP), where the lines of magnetic force
>> intersect the Earth's surface.
>
>The dipole axis/surface intersect is the phyical point where the
>earths average pole intersects the surface, it insects at a different
>point from the magnetic dip maximum because the the pole does not
>cross through the center of the earth and is on a skewed 'parallel'
>from the rotational axis.

The north magnetic pole is traditionally taken as the 'dip pole', the
region where the lines of flux are normal (vertical) to the surface.
See http://sarbc.org/pole.html for example.

The notional axis of the earths magnetic field is a distinctly fuzzy
ide for the simple reason that the earths magnetic field is far more
complex that of a simple bar magnet. See the spaghetti of
http://www.astronet.ru/db/xware/msg/1181025 Somewhere in the internet
is a plot of the magnetic field at the south pole that shows that at
the moment there are three regions of 90degree dip and it's anyone's
guess where you place the intercept of the earth's magnetic field in
this region. Unfortunately I can't find the diagram but
http://www.pureenergysystems.com/news/2005/02/27/6900064_Magnet_Pole_Shift/
gives some idea of the background.

The NMP which Daryl referred to as the place to which a compass needle
points is determined on the basis of magnetic declination (see
http://www.ngdc.noaa.gov/seg/geomag/icons/WMM-00D.gif ) and appears to
be in a different position, according to where you are at the time.
Theoretically it corresponds with the pole of bar magnet. The magnetic
north pole as determined by compass generally corresponds with neither
the dip pole nor the notional axis. In fact, a magnetic compass is
useless in the vicinity of the magnetic pole.

---- snip ----
>
>> In the time of Norse exploration
>> in northern Baffin Bay, it might have been further away,
>> but the point on the earth's surface below the centre
>> of the auroral ring might well have been used as a proxy
>> for the location of the North Pole, and for the era when
>> Europeans might have been exploring near Thule, it was
>> to the north of Thule, and that's a good enough source of
>> a myth of a north pole with four islands and strong currents
>> for me.
>
>I seriously doubt it, and even if it were true, the Inventio
>Fortunata, as we know what was in it (which is not much), would be
>considered a fabrication.
>
The logical connection is ... ?



Eric Stevens

.

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