by AYLIN WOODWARD
- Earth’s magnetic north pole keeps moving as our planet’s magnetic field changes.
- It has moved so much, in fact, that scientists issued an early update to the World Magnetic Model (WMM) in February.
- The WMM informs everything from Google Maps to the US Department of Defense’s navigation systems.
- The latest version of the WMM, published December 10, shows that magnetic north is still moving towards Siberia from eastern Canada.
Earth’s magnetic north pole has been leading scientists on something of a wild goose chase.
Over the last 40 years, the spot toward which all our compasses point has moved by an average of about 30 miles per year. In September, magnetic north aligned briefly with geographic north (where all the lines of longitude converge at the North Pole) as it passed over the Prime Meridian.
But then it kept moving, skittering from its previous location in Nunavut, Canada towards Siberia.
“Magnetic north has spent the last 350 years wandering around the same part of Canada,” Ciaran Beggan, a scientist from the British Geological Survey (BGS), told Business Insider. “But since the 1980s, the rate it was moving jumped from 10 kilometers [6.2 miles] per year to 50 kilometers [31 miles].”
Beggan is part of a group of scientists who track the errant pole from year to year. Their work informs the World Magnetic Model (WMM), a map of the planet’s magnetic field.
According to the most recent update of the WMM, magnetic north is still zooming along, though its speed has decreased a bit, to 24.8 miles per year.
“By 2040, all compasses will probably point eastward of true north,” Beggan said, adding that magnetic north’s march toward northern Russia is far from over.
Magnetic north is crucial for navigation systems
Earth’s magnetic field is a sheath of geomagnetic energy that shields the planet from deadly and destructive solar radiation. Without it, solar winds could strip Earth of its oceans and atmosphere.
But the magnetic field and its poles aren’t static. Since scientists discovered the magnetic north pole’s existence in 1831, it has moved 1,400 miles. Magnetic south, however, hasn’t moved at all in the last century, Beggan said.
Keeping tabs on changes in the magnetic field is imperative for European and American militaries, since their navigation systems rely on it. So, too, do GPS apps and commercial airlines.
That’s why every five years, BGS and NOAA release an updated World Magnetic Model.
The WMM isn’t a static snapshot of what the Earth’s magnetic field looks like every five years. Rather, it’s a list of numbers that allows devices and navigators to calculate what the magnetic field will look like anywhere on Earth at any time during the five years after the model was published. The WMM was updated for 2015 and scheduled for another update for 2020.
Recently, however, magnetic north’s gambol around the Arctic accelerated so much that the movement made the WMM inaccurate.
Mapping a moving field
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