Once again, I may be showing my ignorance but how is that dip any different
from what I could cause by holding the compass in a non-level orientation?
In that case, I just level it myself. Isn't that the solution in this case?
I could see a problem if the compass was mounted in a fixed position on a
ship but it ain't too stable on my console anyways!

Earth's Magnetic Pole Drifting Quickly

 By ALICIA CHANG
AP Science Writer
Dec 09 7:28 PM US/Eastern

SAN FRANCISCO - Earth's north magnetic pole is drifting away from North
America and toward Siberia at such a clip that Alaska might lose its
spectacular Northern Lights in the next 50 years, scientists said Thursday.
Despite accelerated movement over the past century, the possibility that
Earth's modestly fading magnetic field will collapse is remote. But the
shift could mean Alaska may no longer see the sky lights known as auroras,
which might then be more visible in more southerly areas of Siberia and
Europe.

The magnetic poles are part of the magnetic field generated by liquid iron
in Earth's core and are different from the geographic poles, the surface
points marking the axis of the planet's rotation.
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Scientists have long known that magnetic poles migrate and in rare cases,
swap places. Exactly why this happens is a mystery.

"This may be part of a normal oscillation and it will eventually migrate
back toward Canada," Joseph Stoner, a paleomagnetist at Oregon State
University, said Thursday at an American Geophysical Union meeting.

Previous studies have shown that the strength of the Earth's magnetic shield
has decreased 10 percent over the past 150 years. During the same period,
the north magnetic pole wandered about 685 miles out into the Arctic,
according to a new analysis by Stoner.

The rate of the magnetic pole's movement has increased in the last century
compared to fairly steady movement in the previous four centuries, the
Oregon researchers said.

At the present rate, the north magnetic pole could swing out of northern
Canada into Siberia. If that happens, Alaska could lose its Northern Lights,
which occur when charged particles streaming away from the sun interact with
different gases in Earth's atmosphere.

The north magnetic pole was first discovered in 1831 and when it was
revisited in 1904, explorers found that the pole had moved 31 miles.

For centuries, navigators using compasses had to learn to deal with the
difference between magnetic and geographic north. A compass needle points to
the north magnetic pole, not the geographic North Pole. For example, a
compass reading of north in Oregon is about 17 degrees east of geographic
north.

In the study, Stoner examined the sediment record from several Arctic lakes.
Since the sediments record the Earth's magnetic field at the time,
scientists used carbon dating to track changes in the magnetic field.

They found that the north magnetic field shifted significantly in the last
thousand years. It generally migrated between northern Canada and Siberia,
but it sometimes moved in other directions, too.

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On the Net:

American Geophysical Union: http://www.agu.org