Earth’s North Magnetic Pole is Unpredictably Moving Away from the Canadian Arctic and Toward Siberia
Earth’s north magnetic pole is unpredictably moving away from the Canadian Arctic and toward Siberia. It’s travelled so much, that the present representation of the entire globe’s magnetic field, which was updated in 2015, is no longer accurate causing geologists to come up with a new model.
This updated model, known as the World Magnetic Model, was supposed to be published Jan. 15, however, it’s been pushed back to Jan. 30, due to the government shutdown.
Once it goes public, the new model will advise a wide array of navigation, such as people directing airplanes and ships and people checking Google Maps on their smartphones.
There are more models than just the World Magnetic Model — another is known as the International Geomagnetic Reference Field, which tracks so-called declination, or the difference between true, or geographic, north (that is, the North Pole) and magnetic north (the place where your compass needle points). Knowing that declination for points across the planet enables an individual to convert between a magnetic bearing and a true bearing, as per a report on the 2015 model. Using this method, ships, aircraft, antennas, drilling equipment and other devices can be oriented.
The most recent World Magnetic Model was created to last until 2020, but magnetic north’s rapid and unexpected move toward Siberia was so intense, that researchers had to fix the model early, according to Arnaud Chulliat, a geomagnetist at the University of Colorado Boulder and the National Oceanic and Atmospheric Administration’s (NOAA’s) National Centers for Environmental Information.
The magnetic north’s wanderings aren’t exactly new. In the 1800s researchers realized that magnetic north tended to drift. Then, in the mid-1990s, it started to move faster, from just over 9 miles (15 kilometres) a year to about 34 miles (55 km) yearly, as reported by Nature. In 2018, magnetic north moved across the International Date Line and entered the Eastern Hemisphere.
The North Pole’s unpredictable movements are mostly due to the Earth’s liquid-iron outer core, called the core field. (Magnetic minerals in the crust and upper mantle, in addition to the electric currents caused by the flow of seawater, also play a role. However, these influences are small compared to those from the core field, as per the 2015 report on the World Magnetic Model.)
Although no one has ever seen the core field, it can be imagined as a bar magnet at the center of the Earth that has two poles: north and south. This magnet represents approximately 75% of the intensity of the Earth’s magnetic field at the surface today, according to Ronald Merrill, an emeritus professor of Earth and space sciences at the University of Washington, who wasn’t involved with the new World Magnetic Model research. (In reality, electric currents and not a giant bar magnet in Earth’s core create the magnetic field, but it’s simpler to think of it concerning magnets, explained Merrill.)
However, the intensity of this so-called bar magnet is weakening as time goes on, by around 7% every century, said Merrill to Live Science. That bar magnet is also moving right now so that it’s tilted toward Canada at just under 10 degrees.
The other 25% of the magnetic field comes from another domain, which can be imagined as bar magnets that are moving around, explained Merrill. As the giant, central bar magnet loses its intensity, this other magnetic field obtains more influence over Earth’s magnetic field, causing this field to move in the direction of Siberia, as per Merrill.
Some scientists are alarmed by the weakening of this giant bar magnet. They wonder if it’s a sign that Earth’s north and south poles might flip, as they last did around 780,000 years ago. This flip wouldn’t happen for thousands of years, so it remains to be seen what will take place. However, a 2018 study in the journal Proceedings of the National Academy of Sciences discovered evidence that Earth’s magnetic field has weakened before without flipping.
But, this weakening could lead to a field wobble, which could affect technologies like electronics aboard low-Earth-orbit satellites, as previously reported by Live Science.
What’s more, a roving magnetic north has other implications. As it moves, there’s a chance that the best locations to see the Northern Lights will change as time goes on.
As of now, scientists are trying to determine precisely why magnetic north is moving toward Siberia. One hypothesis is that its rapid flight is linked to a high-speed jet of liquid iron under Canada, as reported by Nature.
It seems that this jet is weakening the magnetic field beneath Canada by smearing it out, which means that Canada doesn’t stand a chance against Siberia, said Phil Livermore, a geomagnetist at the University of Leeds, in England.
“The location of the north magnetic pole seems to be controlled by two large-scale patches of magnetic field, one beneath Canada and one beneath Siberia,” Livermore told Nature. “The Siberian patch is winning the race.
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