The Magnetic North Pole – the spot that every compass points at – has been on the move since British explorer James Clark Ross first plotted its position it in 1831.
But while the pole’s movement had been tracking at a fairly leisurely 9 miles a year for most of the past two centuries, scientists say that since the 1990s it has begun up speed, and is now drifting southwards at close to 40 miles a year.
Towards the end of October 2017 the magnetic north pole crossed the international date line, passing within 240 miles of the geographic north pole, and is now heading towards the chilly Russian province of Siberia.
A paper published in the scientific journal Nature Geoscience by researchers Philip W. Livermore, Christopher C. Finlay and Matthew Bayliff explains exactly why this is happening.
“The wandering of Earth’s north magnetic pole, the location where the magnetic field points vertically downwards, has long been a topic of scientific fascination,” the researchers say.
They explain that the Earth’s magnetic field is generated by our planets large metallic core, and that two sizeable priced of the core are moving around.
The “tussling magnetic blobs deep below Earth’s surface,” as the researchers put it, are pulling the pole’s location southwards.
Phil Livermore, from the University of Leeds, told EarthSky: “By analysing magnetic field maps and how they change over time, we can now pinpoint that a change in the circulation pattern of flow underneath Canada has caused a patch of magnetic field at the edge of the core, deep within the Earth, to be stretched out
"This has weakened the Canadian patch and resulted in the pole shifting towards Siberia.”
The phenomenon is not just a scientific curiosity, the researchers point out, Even in the era of GPS we have to be careful that we understand what our compasses are telling us.
The European Space Agency explained: “One of the practical consequences of this is that the World Magnetic Model has to be updated periodically with the pole’s current location.
"The model is vital for many navigation systems used by ships, Google maps and smartphones, for example”.
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