On Dec. 17, the World Magnetic Model was updated, predicting the magnetic north pole’s shift for the next five years. Here’s why this crucial change was made.
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Magnetic North Pole on the Move What’s Causing the Shift?
Magnetic North Pole on the Move
On December 17, the National Centers for Environmental Information (NCEI) and the British Geological Survey (BGS) released an updated version of the World Magnetic Model, predicting how Earth’s magnetic field will shift and evolve over the next five years. This crucial model underpins everything from satellite navigation and aircraft orientation to the maps we use on our smartphones, like Google Maps. By accurately predicting the difference between magnetic north and true north at every point on Earth, the World Magnetic Model ensures that our devices can orient themselves correctly, even as the magnetic north pole moves slightly each year. While most users won’t notice any immediate changes as a result of this update, the changes are vital to maintaining the accuracy of navigation systems and making better future predictions about the behavior of Earth’s magnetic field. The update is part of a five-year cycle, timed to ensure that these technologies remain precise and reliable, adapting smoothly to the continually shifting dynamics of Earth’s outer core. According to William Brown, a geophysicist at the BGS who helped create and update the World Magnetic Model, “Your smartphone or GPS system has a magnetometer, effectively a digital compass built into it. It measures the direction of the magnetic field where you are, and it enters your position into the World Magnetic Model software to tell it what the magnetic field should look like.
Small deviations from the predicted field can accumulate over time and occasionally compound to the point where the model must be updated more frequently. For example, the NCEI and BGS released an off-cycle update in 2019 to account for the outer core flowing faster than usual in the Northern Hemisphere — a phenomenon that caused the magnetic north pole to shift much more quickly than usual.
But for most people, the 2025 update won’t result in any noticeable changes to navigation, and users won’t have to change anything for phone map apps to work properly.
“You should be able to navigate as well as you could yesterday,” Brown said. “We keep the updates coming so that it’s only a bit of time, small enough that most people don’t notice, because for most users, the accuracy is more than they need anyway.”
The World Magnetic Model is essentially a snapshot of Earth’s magnetic field at a given moment, combining data from satellites like the European Space Agency’s Swarm mission and high-precision magnetometers at ground-based observatories. Earth’s magnetic field is generated deep within the planet’s outer core, a layer of molten iron and nickel 2,200 to 3,100 miles beneath the surface.
The movement of this conductive liquid iron generates electric currents, creating a magnetic field—a process known as the geodynamo. This self-sustaining process has been at work for billions of years, keeping Earth’s magnetic field intact. The constant motion of the outer core causes the magnetic north pole to shift, typically moving tens of miles per year. These shifts are not regular or predictable, which is why the World Magnetic Model is updated every five years to ensure that our navigation systems can handle these changes seamlessly. For most users, the 2025 update won’t result in any noticeable changes; however, for devices that depend on accurate magnetic orientation, these updates are crucial.
“The real challenge,” says Bruce Buffett, a geophysicist at the University of California, Berkeley, “is that the magnetic field doesn’t change in a regular, predictable manner. We release a model every five years to account for the irregular, chaotic nature of the outer core’s motion. It’s all about keeping our navigational systems precise and reliable for the future