The Magnetic Model update was officially released on Feb. 4 and the magnetic north can again be precisely located for people around the world.
This is breaking news to lots of us, but the truth is that magnetic north has never sat still.
In the last 100 years or so, the direction in which our compasses steadfastly point has lumbered ever northward, driven by Earth’s churning liquid outer cored some 1,800 miles beneath the surface.
In recent years, scientists noticed something unusual: Magnetic north’s routine plod has shifted into high gear, sending it galloping across the Northern Hemisphere — and no one can entirely explain why.
The changes have been so large that scientists began working on an emergency update for the World Magnetic Model, the mathematical system that lays the foundations for navigation, from cell phones and ships to commercial airlines.
But then the U.S. government shutdown, placing the model’s official release on hold, as Nature News first reported earlier this year.
Now, the wait for a new north is over.
The model is updated every five years, with the last update in 2015.
Between each update, scientists check the model’s accuracy against data from ground magnetic observatories and the European Space Agency’s Swarm mission — a trio of magnetic-field mapping satellites that zip around the Earth 15 to 16 times each day. Until now, this seemed sufficient to keep up with the magnetic north’s march toward Siberia.
In the mid 1900s, the north magnetic pole was lumbering along at less than 100 feet each day, adding up to seven miles of difference each year. But in the ‘90s, this started to change. By the early aughts, magnetic north was chugging along at some 34 miles each year.
To keep up with all these changes, the U.S. National Oceanic and Atmospheric Administration and the British Geological Survey developed what eventually became known as the World Magnetic Model, “so they would all be on the same map, essentially,” Ciaran Beggan, a geophysicist with the BGS said.
Beggan said the average user is not going to be overly affected by this unless they happened to be trekking around the high Arctic.
Interest in these unexpected jolts is about more than mapping. The dance of Earth’s magnetic field lines presents one of the few windows scientist have to processes that happened thousands of miles below your feet.
At the 2018 American Geophysical Union fall meeting, one scientist presented what he calls a magnetic field “tug-of-war” that may offer an explanation for the recent odd behavior. The north magnetic pole seems to be controlled by two patches of magnetic field, one under northern Canada and one under Siberia.
Historically, the one under northern Canada seems to have been stronger, keeping the magnetic pole in its clutches. But recently that seems to have changed.
The Siberian patch looks like it’s winning the battle. It’s sort of pulling the magnetic field all the way across to its side of the geographic pole. If you are having trouble with your cell phone, don’t blame it on your device. It may be that the Magnetic north just is traveling some more.