Earth's Magnetic North Pole Is Shifting Toward Siberia and Raising Questions About Unusual Movement
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Earths Magnetic North Pole Is Shifting Toward Siberia and Raising Questions About Unusual MovementScientists released an update to a model that maps the ever-moving pole and has significant implications for navigation systemsElla JeffriesStaff ContributorJanuary 24, 2025 12:41 p.m. The magnetic north pole, distinct from the geographic North Pole, is the point where Earths magnetic field lines converge. NASA via RawpixelFor decades, Earths magnetic north pole has been slowly drifting across the Arctic, but recent shifts in its path have caught the attention of scientistsand those who rely on precise navigation systems. The magnetic north poles movement, which has suddenly accelerated toward Siberia this century, raises questions about whats driving the unusual shift and why its motion matters.The magnetic north pole is distinct from the geographic North Pole, a fixed point where the Earths axis meets its surface. Instead, magnetic north is the changing location where the planets magnetic field lines converge. This field is generated by the churning of the planets outer core, a layer of molten iron and nickel that begins roughly 1,800 miles beneath Earths surface. As the fluid dynamics of the core change, the magnetic pole shifts over time in a process known as the geodynamo. Now, something unusual seems to be happening.The current behavior of magnetic north is something that we have never observed before, William Brown, a global geomagnetic field modeler at the British Geological Survey, says in a statement.Since it was first discovered in 1831 by explorer James Clark Ross, the magnetic north pole has gradually shifted. Over the past century, its movement from Canada toward Russia has accelerated, increasing from about 6 miles per year to a peak of 31 miles annually by the 2000s. However, in the last five years, the rate of movement has slowed significantly to about 22 miles per year, the biggest deceleration in speed weve ever seen, Brown adds in the statement.British and American scientists have traced this motion over time. Every five years, they release a new edition of the World Magnetic Model (WMM), a tool used by GPS systems and navigation devices that maps the north magnetic pole. As of the latest revision, released in December, its location is closer to Siberia than it was five years ago.For industries reliant on magnetic fields, such as aviation, shipping and navigation, this movement is no small matter. GPS systems, planes and military equipment track the magnetic field and rely on accurate models of magnetic north to function properly. When the magnetic field shifts, the models must be updated to reflect the changes.The more you wait to update the model, the larger the error becomes, Arnaud Chulliat, a senior research scientist at the University of Colorado, Boulder, and NOAAs National Centers for Environmental Information, tells Mindy Weisberger of CNN. The way the model is built, our forecast is mostly an extrapolation given our current knowledge of the Earths magnetic field.Scientists are still unsure why the magnetic north poles speed changed so dramatically. Some researchers believe that changes in the strength of the magnetic field near Canada and Siberia could be influencing the shift.Ciarn Beggan, a geophysicist at the British Geological Survey, says the overall strength of Earths magnetic field has been decreasing over the past couple of centuries, but not uniformly. The field is getting weaker in Canada but stronger around Siberia, and that pulls the magnetic pole towards Siberia, Beggan tells Kasha Patel of the Washington Post.However, the exact reasons for the acceleration and subsequent deceleration remain unclear. The behavior of the magnetic field is considered complicated and chaotic, Brown tells Live Sciences Skyler Ware, which is why the WMM must be updated regularly. In 2019, scientists released the WMM one year early, because the magnetic pole was moving much faster than usual.While these changes may seem minor to the average person, they have significant consequences for systems that rely on magnetic fields for navigation. The latest version of the WMM includes a much higher resolution map of magnetic north than ever before to help reduce errors in navigation systems.Scientists say that if you tried traveling the 5,280 miles from South Africa to the United Kingdom in a straight line using the old WMM, it would leave you 93 miles off course by the end of your trip, per the statement.The WMM update also comes amid broader scientific discussions about the future of Earths magnetic field. Over the last two centuries, the field has weakened by about 9 percent, per the Washington Post. Geophysicists have long speculated that the weakening of the magnetic field could signal a potential geomagnetic reversal, in which the planets north and south magnetic poles swap places.While such an event is not expected to happen any time soon, they have occurred periodically throughout Earths historythe last reversal took place around 780,000 years ago. Scientists are not yet able to predict when the next reversal will occur.As for the magnetic north pole, its future movement is also uncertain.It could change (its) rate, or even speed up again, Brown told CNN. We will continue to monitor the field and assess the performance of the WMM, but we do not anticipate needing to release a new model before the planned update in 2030.Get the latest stories in your inbox every weekday.Filed Under: Astrophysics, Canada, Earth's Core, Explorers, Geography, Geology, Navigation, Physics, Russia , Technology
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