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If you utilize your smartphone for navigation, your system has just received a vital update. Researchers have published a new model monitoring the location of the magnetic north pole, indicating that the pole is presently nearer to Siberia than it was five years ago and continues to veer towards Russia.
Unlike the geographical North Pole, which represents a stable point, the position of the magnetic north pole is influenced by Earth’s magnetic field, which is perpetually shifting. In recent decades, the movement of magnetic north has been extraordinary — it significantly accelerated, then in a later shift, slowed down rapidly — yet researchers are unable to clarify the reasons behind the magnetic field’s peculiar behavior.
Global positioning systems, inclusive of those employed by aircraft and vessels, ascertain magnetic north via the World Magnetic Model, which was introduced in 1990. Crafted by the British Geological Survey and the National Oceanic and Atmospheric Administration, this model documents the defined position of magnetic north and forecasts future movement based on the trends observed in recent years. To maintain the precision of GPS readings, researchers update the WMM every five years, recalibrating the official position of magnetic north and providing fresh predictions for the next five years of movement.
“The longer you delay updating the model, the greater the error becomes,” stated Dr. Arnaud Chulliat, a senior research scientist at the University of Colorado, Boulder, along with the NOAA National Centers for Environmental Information. “Based on how the model is constructed, our estimation is primarily an extrapolation derived from our current understanding of the Earth’s magnetic field.”
The researchers unveiled two models on December 17: the standard WMM, featuring a spatial resolution of around 2,051 miles (3,300 kilometers) at the equator, and the first high-resolution model, boasting a spatial resolution of approximately 186 miles (300 kilometers) at the equator. Although anyone can utilize the more advanced high-resolution model, most GPS devices used by the general populace integrate the standard WMM and lack the capacity to accommodate the alternative — many users may not gain from the enhancement, as noted by Dr. William Brown, a geophysicist and geomagnetism investigator from the British Geological Survey, in an email.
“Major airlines will upgrade the navigation software throughout their entire fleets to incorporate the new model, and militaries within NATO will need to enhance software across a myriad of sophisticated navigation systems for various kinds of equipment,” Brown informed CNN. However, for most individuals, the transition is not essential.
“Consider it akin to updating your smartphone — you don’t automatically need to purchase a new phone just to refresh an application to a newer version that is more powerful,” he remarked.
Transitioning to the new model should be an effortless process for GPS users; with the update, scientists confirmed the accuracy of the previous model’s predictions regarding where magnetic north would be situated by 2025, Chulliat stated.
“The prediction was quite accurate,” he stated. “Thus, the new model validated that our estimates were not too far off.”
But what is the reason for these updates, and why doesn’t magnetic north remain stationary?
At the pinnacle of the planet, in the center of the Arctic Ocean rests the geographic North Pole, the place where all longitudinal lines that wrap around Earth from top to bottom meet in the north.
Designating the North Pole is difficult, as it is obscured by shifting sea ice, yet its geographical position, often referred to as the true North Pole, remains constant.
In contrast, the magnetic north pole is the northernmost point where Earth’s magnetic field converges, also identified as the magnetosphere. Produced by the swirling molten metals within Earth’s core, the magnetosphere protects the planet from damaging solar radiation and prevents solar winds from eroding Earth’s atmosphere.
Due to the convective movement in Earth’s core being unceasing, the magnetosphere is never stationary. Consequently, its northernmost location is perpetually changing.
British navigator Sir James Clark Ross identified the magnetic north pole in 1831 in northern Canada, roughly 1,000 miles (1,609 kilometers) south of the true North Pole. It is now understood that every day, magnetic north follows an elliptical route of approximately 75 miles (120 kilometers).
Since its initial discovery, the magnetic north has drifted from Canada towards Russia. By the 1940s, magnetic north had shifted northwest from its 1831 position by nearly 250 miles (400 kilometers). In 1948, it arrived at Prince Wales Island, and by 2000 it had left Canadian waters.
“It has generally shifted approximately 10 km (6.2 miles) annually or less over the past 400 years,” said Brown.
Nevertheless, the most recent WMM update comes after a period of exceptionally abnormal activity for the magnetic north pole. In 1990, its northern migration sped up, growing from 9.3 miles (15 kilometers) each year to 34.2 miles (55 kilometers) annually, Chulliat noted. The shift “was unparalleled based on our available records,” he added.
Around 2015, the drift decelerated to roughly 21.7 miles (35 kilometers) per year. The swift deceleration was similarly unprecedented, Chulliat said. By 2019, the fluctuations had strayed to such an extent from the earlier model that scientists updated the WMM a year ahead of schedule.
Researchers anticipate that the drift towards Russia will keep slowing, yet there remains some ambiguity regarding how long the deceleration will last and whether it will proceed at its present rate, as stated by Brown.
“It could alter (its) velocity, or even accelerate again,” remarked Brown. “We will continue to observe the field and evaluate the WMM’s performance, but we do not foresee the necessity to release a new model prior to the scheduled update in 2030.”
The Earth’s magnetic field has exhibited even more extreme behaviors in the past, to the extent that the magnetosphere weakened significantly enough to reverse its polarity. This reversal swaps the magnetic north and south poles, with the change potentially enduring for tens of thousands of years. Scientists estimate that this polar reversal, which may take millennia to finalize, occurs approximately once every million years, although the intervals between reversals have varied widely — from 5,000 years to as long as 50 million years. The indicators preceding such reversals are also not well comprehended, rendering them hard to forecast, Brown noted. The most recent major inversion happened around 750,000 to 780,000 years ago.
During a polar inversion, creatures that navigate using the magnetic field for orientation, such as whales, butterflies, sea turtles, and various types of migratory birds, might be impacted. A reversal would disturb radio communications and interfere with navigation systems. Satellites in orbit would face threats, as a diminished magnetic field would provide less safeguard against solar activity.
While life on Earth has endured multiple magnetic reversals over more than 100 million years, “we’ve never faced a reversal when contemporary technology was in existence,” Brown remarked.
“It would undoubtedly be an intriguing period for engineers to adjust our technology to, but ideally one they’d have a gradual, centuries-long buildup to, rather than any abrupt change.”
Mindy Weisberger is a science journalist and media producer whose contributions have been featured in Live Science, Scientific American, and How It Works magazine.