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After some 400 years of relative stability, Earth's North Magnetic Pole has moved nearly 1,100 kilometers out into the Arctic Ocean during the last century, scientists from Oregon State University reported. If it keeps going at the present clip, it will move from northern Canada to Siberia within the next half-century.
Besides the possibility that Alaskans, the Inuit and other natives of northern Norh America may loose the sight of the Northern Lights for many generations, the shift has implications for international travel and communications. The scientists said that radiation influx associated with our planet's magnetic field affects charged particles streaming down through the atmosphere can impact airplane flights and telecommunications.
"This may be part of a normal oscillation and it will eventually migrate back toward Canada," said Joseph Stoner, assistant professor at the university' s College of Oceanic and Atmospheric Sciences. "There is a lot of variability in the polar motion, but it isn't something that occurs often. There appears to be a 'jerk' of the magnetic field that takes place every 500 years or so. The bottom line is that geomagnetic changes can be a lot more abrupt than we ever thought."
The scientists said in a press release that calculations of the North Magnetic Pole's location from historical records goes back only about 400 years, while polar observations trace back to John Ross in 1838 at the west coast of Boothia Peninsula.
To look deeper in the past, the scientists drilled 5-meter core samples from the ice and 5,000 year old sediments deposited on the bottom of frozen Arctic lakes.
These sediments contain magnetic particles called magnetite, the scientists said. Much like a classroom experiment with magnets and iron filings, they record the the orientation of Earth's magnetic field at the time they were deposited. The team then used carbon dating and layer counting to determine approximately when the sediments were deposited and track changes in the magnetic field.
The Oregon team reported that "Earth last went through a magnetic reversal some 780,000 years ago. These episodic reversals, in which south becomes north and vice versa, take thousands of years and are the result of complex changes in the Earth's outer core. Liquid iron within the core generates the magnetic field that blankets the planet."
Because of that field, a compass reading of north in Oregon will be approximately 17 degrees east from 'true geographic north.' In Florida, farther away and more in line with the poles, the declination is only 4-5 degrees west."
The Northern Lights, which are triggered by the sun and fixed in position by the magnetic field, drift with the movement of the North Magnetic Pole and may soon be visible in more southerly parts of Siberia and Europe - and less so in northern Canada and Alaska."
No word on whether the southern magnetic pole is undergoing silimar shift.
One beguiling question also remains unaswered. Could it be the movement of Earth's crust that's actually sped up? After all, it was magnetite crystals recovered from basalts in Greenland in the 1960s that proved the movement of plate tectonics and pointed to the existence of Pangea, the mother of all continents.

Image Credit: University of Northern British Columbia