The Arizona Republic

Magnetic north pole is rapidly on the move

- Seth Borenstein AP

WASHINGTON – where it used to be.

Earth’s north magnetic pole has been drifting so fast in the past few decades that scientists say that previous estimates are no longer accurate enough for precise navigation. On Monday, they released an update of where magnetic north really was, nearly a year ahead of schedule.

The magnetic north pole is wandering about 34 miles a year. It crossed the internatio­nal date line in 2017, and is leaving the Canadian Arctic on its way to Siberia.

The constant shift is a problem for compasses in smartphone­s and some consumer electronic­s. Airplanes and boats also rely on magnetic north, usually as backup navigation, said University of Colorado geophysici­st Arnaud Chulliat, lead author of the newly issued World Magnetic Model. GPS isn’t affected because it’s satellite-based.

The military depends on where magnetic north is for navigation and parachute drops, while NASA, the Federal Aviation Administra­tion and U.S. Forest Service also use it.

Airport runway names are based on their direction toward magnetic north, and their names change when the poles move. For example, the airport in Fairbanks, Alaska, renamed a runway 1L-19R to 2L-20R in 2009.

The U.S. National Oceanic and Atmospheri­c North isn’t quite Administra­tion and United Kingdom tend to update the location of the magnetic north pole every five years in December, but this update came early because of the pole’s faster movement.

The movement of the magnetic north pole “is pretty fast,” Chulliat said.

Since 1831, when it was first measured in the Canadian Arctic, it has moved about 1,400 miles toward Siberia. Its speed jumped from about 9 miles a year to 34 miles a year since 2000.

The reason is turbulence in Earth’s liquid outer core. There is a hot liquid ocean of iron and nickel in the planet’s core where the motion generates an electric field, said University of Maryland geophysici­st Daniel Lathrop, who wasn’t part of the team monitoring the magnetic north pole.

“It has changes akin to weather,” Lathrop said. “We might just call it magnetic weather.”

The magnetic south pole far slower than the north.

In general, Earth’s magnetic field is getting weaker, leading scientists to say that it will eventually flip, where north and south pole change polarity, like a bar magnet flipping over.

It has happened numerous times in Earth’s past, but not in the past 780,000 years.

“It’s not a question of if it’s going to reverse, the question is when it’s going to reverse,” Lathrop said.

When it reverses, it won’t be like a coin flip, but will take 1,000 or more years, experts said. is moving

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Harri Venalainen navigates an icebreaker through the Beaufort Sea.

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