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The North Magnetic Pole moves towards Siberia at a slower pace: what can mean

A new edition of the World Magnetic Model (Wmm), a model of the British Geological Survey and Noaa (National Oceanic and Atmospheric Administration) which identifies the updated position of the North Magnetic Pole. Since the northern magnetic pole began to monitor it in the nineteenth century He is migrating from Canada to Siberia. In the last century he moved and faster and fasterreaching i 50 km/yearbut now he is slowing down (he moves to 35 km/year). The phenomenon is linked to one variation of the earth’s magnetic field due to the movements of the fluid external nucleus of the earth, even if the reasons for the slowdown are not completely clear. Knowing the movements of the North Magnetic Pole is essential to maintain the accuracy of Satellite navigation systems (GPS), used for example by ships and planes, but also for military and scientific purposes.

What are the Earth’s magnetic field and the North Magnetic Pole

The earth has a huge magnetic field which protects us from the harmful radiation that come from space and is believed to originate from electric fields in the Fluid external nucleusmainly made up of iron. We can think of the earth’s magnetic field as the one generated by a gigantic bar magnet placed in the center of the earth. The points where the axis passing through the bar meet the earth’s surface are the geomagnetic poles (or earthly magnetic poles), which do not coincide with geographical ones, instead given by the intersection of the earth’s axis with the surface of the earth. The North Magnetic Pole, in which the lines of strength of the magnetic field converge, is indicated by the Bussola’s needle. The earth’s magnetic field (and therefore also the magnetic poles) is not fixed, but undergoes variations over time. During the history of the earth it is inverted many times: to testify to it are particular minerals (said ferromagnetic) contained in the rocks that record the orientation of the Earth’s magnetic field at the time of their training. When the magnetic field is reversed, the North Magnetic Pole takes the place of the southern magnetic pole and vice versa.

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The earth’s magnetic field, with the lines of force that enter the North Magnetic Pole.

How to move the magnetic north pole and why

Since it was located for the first time, in 1831from the explorer James Clark Rossthe North Magnetic Pole has progressively moved From Canada to Siberia. His movement was faster and faster: in the last century it has passed by about 10 km/year about 50 km/year. However, in the last five years he has Suddenly slowed downpassing to about 35 km/year. “The current behavior of the magnetic North is something that we have never observed before“, Says William Brown of the British Geological Survey, adding that this is”The largest deceleration of the speed we have ever seen“.

At the basis of the movements of the North Magnetic Pole, as well as the inversions of the Earth’s magnetic field, there are the changes in the dynamics of materials which constitute the fluid external nucleus. However, it is not clear why in recent decades the movement of the pole has undergone acceleration while now it is slowing down. Some researchers believe that theintensity overall of the Earth’s magnetic field in the last two centuries has decreased in a non -uniform way: It would have weakened near Canada while it would strengthen at Siberia, making the pole moves right towards the latter.

The weakening of the magnetic field could announce a future reversal of the magnetic fieldeven if we don’t know when this will happen. The inversion, being accompanied by a decrease in the intensity of the magnetic field, would be dangerous for living beingswhich would be less protected from ultraviolet radiation and cosmic rays towards which the earth’s magnetic field acts as a shield.

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The movement of the North Magnetic Pole from 1590 to 2030. Credit: Ukri, Wessel, WHF Smith

Because it is important to keep track of the movements of the North Magnetic Pole

It is very important to keep track of the movements of the North Magnetic Pole because they have consequences for the Satellite navigation systems. For example, if its position was not updated, the ships would find themselves off course. For this reason, every five years British and American researchers issue a new edition of the World Magnetic Model (Wmm), which provides a map of the North Magnetic Pole. The Wmm High-Vestion 2025 model, in particular, is ad very high resolutionten times higher than the standard used for previous models. The model also provided forecasts on the trajectory that the North Magnetic Pole could follow in the coming years. However, it is not known with what rhythm the migration will take place, which could slow down or accelerate again.

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The magnetic declination, that is, the corner that the direction of the North Magnetic Pole forms with the direction of the North Geographical Pole, according to the World Magnetic Model 2025. Credit: Noaa Ncei