The magnetic North Pole is moving more quickly than normal

The magnetic North Pole is moving more quickly than normal, sparking fears the Earth's magnetic field could be about to flip - with potentially devastating consequences.

Every five years scientists update the World Magnetic Model, which might sound esoteric but is vitally important for navigation.

But the North Pole is shifting, and the latest model - set in 2015 and expected to last five years - needs to be updated urgently, according to a report in scientific journal Nature.

Contrary to popular belief, compasses don't point to the North Pole - they point to magnetic north, its location determined by the churning of liquid metals inside the Earth. As things inside the Earth change, so do the poles.

magnetic poles
Photo credit: Getty

In the 18th and 19th centuries it travelled eastward across northern Canada, before making an abrupt turn northwards at the start of the 20th century. At the start of the 21st it began speeding up, going from 9km/year in the late 20th century to its present speed of at least 55km/year.

"It didn't move much between 1900 and 1980 but it's really accelerated in the past 40 years," British Geological Survey scientist Ciaran Beggan told Reuters.

It's now not far from the actual North Pole, on a beeline for Siberia.

"The location of the north magnetic pole appears to be governed by two large-scale patches of magnetic field, one beneath Canada and one beneath Siberia," Phil Livermore, a geomagnetist at the University of Leeds, said at a recent meeting, Nature reports.

"The Siberian patch is winning the competition."

Since a massive "geomagnetic pulse" detected beneath South America in 2016, the recent model has been outdated, Nature reports. An urgent meeting was scheduled to be held on January 15 at the request of the US military, but was called off thanks to US President Donald Trump's government shutdown. It's now pencilled in for January 30.

There has been speculation recently that the accelerating pole movement could be a sign the poles are about to flip. Scientists estimate that happens every few hundred thousand years. The last time it happened on a long-term basis was 780,000 years ago, suggesting we're overdue.

About 41,000 years ago a temporary pole reversal lasting 440 years took place, during which time the strength of the Earth's magnetic field dropped 95 percent. If that happened now we'd be bombarded with lethal cosmic rays and the atmosphere might be stripped away, and we wouldn't be able to call 111 because our mobile phones wouldn't work.

A normal reversal would take hundreds to thousands of years to complete, and scientists say it would be a bigger problem for birds who rely on the magnetic field for migration than it would humans.

Scientists who looked into the evidence last year concluded it was "probably" not undergoing a reversal.

And don't delete Google Maps if it does happen. While the magnetic field is important for navigating at sea and the poles, your phone and car navigation system relies more on satellites.

"It doesn't really affect mid or low latitudes," Dr Beggan told Reuters. "It wouldn't really affect anyone driving a car."

The magnetic South Pole isn't directly opposite the North, and its movement doesn't always match. It's spent the last 200 years moving away from the South Pole, and is currently outside the Arctic Circle.

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