The needle of a compass has guided humanity for centuries, pointing unerringly toward the magnetic north. But what happens when that point moves — and accelerates?
This week, scientists unveiled the World Magnetic Model 2025 (WMM2025), a vital update to our understanding of Earth’s restless magnetic field. For navigators, mapmakers, and technologists, it’s a recalibration moment as the model reflects how magnetic north edges closer to Siberia, moving away from its historical Canadian home.
A Magnetic Shift
Magnetic north is not fixed like its geographic counterpart, the North Pole. Instead, it meanders, driven by the roiling motion of molten metals in Earth’s outer core. This relentless churn generates the planet’s magnetic field, a phenomenon first mapped in the Arctic by Sir James Clark Ross in 1831. Since then, the magnetic north pole has trekked over 2,200 kilometers (about 1,400 miles), with its pace quickening dramatically in the last few decades.
Dr. William Brown, a geomagnetic field modeler at the British Geological Survey (BGS), is as baffled as other scientists: “The current behavior of magnetic north is something that we have never observed before. Magnetic north has been moving slowly around Canada since the 1500s but, in the past 20 years, it accelerated towards Siberia.”
This rapid movement peaked at 50 to 60 kilometers per year in the early 2000s, only to decelerate to about 35 kilometers annually in recent years — a slowdown that has intrigued scientists worldwide.
Why WMM2025 Matters
The World Magnetic Model is a cornerstone for modern navigation. Ships, airplanes, and even your smartphone compass rely on this dataset for accuracy. A gap of just a few years without updates could result in significant navigational errors. For instance, traveling 8,500 kilometers (about 5,280 miles) from South Africa to the UK could put you 150 kilometers off course using an outdated model.
So, this year’s release marks a significant leap forward with the introduction of the WMM High Resolution (WMMHR2025). Offering a spatial resolution of 300 kilometers at the equator. More than ten times finer than the previous standard, this high-resolution model ensures pinpoint accuracy.
“Users can now have the most up-to-date information to navigate accurately for the next five years,” said Dr. Brown.
Historically, the WMM has been updated every five years to keep up with these movements. The last update was in 2019.
Blackout zones near the poles, where magnetic navigation becomes unreliable, have also been recalibrated in the update.
The Science Behind the Shift
At the heart of magnetic north’s migration lie two massive magnetic lobes beneath Earth’s crust — one under Canada and the other under Siberia. These subterranean powerhouses exert a tug-of-war on the magnetic pole, with the Siberian lobe recently gaining the upper hand.
The magnetic field itself is a marvel of physics. It emerges from the liquid iron and nickel swirling in the outer core, driven by convection and Earth’s rotation. This dynamo effect generates electric currents, which in turn produce a magnetic field that extends into space, shielding our planet from harmful solar radiation. Understanding this dynamic system requires input from global ground-based measurements and satellite data.
The WMM is the product of international collaboration, jointly developed by NOAA’s National Centers for Environmental Information (NCEI) and the British Geological Survey. Supported by the U.S. National Geospatial-Intelligence Agency and the UK’s Defence Geographic Centre, the model serves governments, commercial sectors, and international organizations such as NATO. It’s also embedded in consumer technologies, ensuring your GPS or compass app functions seamlessly.
As the magnetic north continues its unpredictable journey, the WMM must adapt. So, whether guiding ships through polar waters or ensuring Santa’s sleigh stays on course, this model reminds us of the delicate interplay between science, technology, and the natural forces shaping our world.
