Everyone knows the North Pole. This geographic point represents the highest point on earth. But in reality there are three different “norths” on earth. The first, called geographic, corresponds to the point of convergence of the lines of longitude on Earth.
He never moves. The second, magnetic, moves chaotically. Finally, the last one, that of maps, is only hypothetical and allows planes and boats to easily move around the earth.
Scientists are therefore most interested in magnetic north. In fact, its movement is still a mystery, but a study published in the famous scientific journal Nature offers an interesting theory.
According to a team of researchers from the University of Leeds led by Professor Livermore, the movements of magnetic north are caused by the random flow of molten iron at the heart of our planet.
Metals of all kinds are melted in the earth’s core. Iron, one of the heaviest and most stable elements in the universe, moves much less than the others. But these rare moves have consequences right up to the surface.
A “North” in constant motion
The scientists explain that the movement of a few millimeters of iron in the heart of the earth can have an impact of several kilometers on the surface. Magnetic north, first discovered in 1830, has never been perfectly positioned with respect to true north.
This difference has long been explained by the tilt of the earth on itself. Today, magnetic north, which is level with Canada, is approaching Siberia faster than before.
Scientists agreed that the movement of the latter was 10 kilometers per year. Today it would be more like around 50 kilometers per year. These deviations are not without consequences for us.
Sailors and migratory birds: the first to be affected?
If the changes in everyday life were rather small, the sailors would certainly be affected the most. They are the ones who most commonly use magnetic north, along with compasses, to orient themselves.
While the latter just aligns to true north, the offsets of one to two degrees are no longer necessary. This change should make navigation easier and more accurate. Migratory birds are also affected by this change.
It is unlikely that the birds will be lost
You feel the movements of magnetic north and let them guide you. If this current shift is strong enough, however, it is not enough to lose these birds in flight. Once within sight of the coast, you will always find your way around.
Magnetic north movements are expected to continue throughout the year, according to scientists at Ordnance Survey, a magnetic north tracking organization. The northern flight path will pass on the other side of the Greenwich meridian in a few days before leaving the English coast in 2025.
The movements of magnetic north: source of many theories
The movements of the magnetic north pole are now scientifically explained (and predicted), but some groups of people continue to attribute supernatural powers to such a phenomenon. For many climate skeptics, the acceleration of magnetic north would be caused by a warming of the sun (so far this is partially true) and thus cause global warming.
In more than 100 years of research, no scientific study has been able to find a connection between the movement of magnetic north and global warming, but this idea is still valid.
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