North Magnetic Pole Moving Due to Core Flux

The core is too deep for scientists to directly detect its magnetic field. But researchers can infer the field's movements by tracking how Earth's magnetic field has been changing at the surface and in space.

Now, newly analyzed data suggest that there's a region of rapidly changing magnetism on the core's surface, possibly being created by a mysterious "plume" of magnetism arising from deeper in the core.

And it's this region that could be pulling the magnetic pole away from its long-time location in northern Canada, said Arnaud Chulliat, a geophysicist at the Institut de Physique du Globe de Paris in France.

Finding North

Magnetic north, which is the place where compass needles actually point, is near but not exactly in the same place as the geographic North Pole. Right now, magnetic north is close to Canada's Ellesmere Island.

Navigators have used magnetic north for centuries to orient themselves when they're far from recognizable landmarks.

Although global positioning systems have largely replaced such traditional techniques, many people still find compasses useful for getting around underwater and underground where GPS satellites can't communicate.

The magnetic north pole had moved little from the time scientists first located it in 1831. Then in 1904, the pole began shifting northeastward at a steady pace of about 9 miles (15 kilometers) a year.

In 1989 it sped up again, and in 2007 scientists confirmed that the pole is now galloping toward Siberia at 34 to 37 miles (55 to 60 kilometers) a year.

A rapidly shifting magnetic pole means that magnetic-field maps need to be updated more often to allow compass users to make the crucial adjustment from magnetic north to true North.

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