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Despite accelerated movement over the past century, the possibility that the Earth's fading magnetic field will collapse or that the magnetic poles will flip is remote. But the shift could mean that Alaska may no longer be able to see the high-altitude shimmering displays of colourful lights known as auroras.

Scientists have long known that magnetic poles migrate and in rare cases, swap places. But exactly why this happens is a mystery. "This may be part of a normal oscillation and it will eventually migrate back toward Canada," said Joseph Stoner, a paleomagnetist at Oregon State University.

Results were presented at an American Geophysical Union meeting. Previous studies have shown that the strength of the Earth's protective magnetic shield has decreased 10 per cent over the past 150 years. During the same period, the north magnetic pole wandered about 1102 km out into the Arctic, according to a new analysis by Stoner.

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 the earth's atmosphere.

The Earth's magnetic poles are different from its geographic poles, which indicate the rotation axis around which it spins. The north magnetic pole was first discovered in 1831 and when it was revisited in 1904, explorers found that the pole had moved 50 km since it was first found.