What Happens if the Magnetic North Pole Keeps Rushing Toward Siberia?
On Monday, the World Magnetic Model was updated to account for the north pole's eccentric behavior, after a delay caused by the US federal shutdown.
by Becky Ferreira
February 5, 2019, 4:32pm
Updated World Magnetic Model, Feb 4, 2019. Image: NOAA NCEI
Earth's north magnetic pole, a wandering point where magnetic field lines vertically enter and exit our planet, has been acting weird lately.
Some 20 years ago, the pole was moving at about 15 kilometers per year, from Canada toward Siberia. But its current clip is 55 kilometers per year, nearly four times faster. In 2018, it passed the International Date Line and entered the Eastern Hemisphere.
Because many navigational systems are based on accurate readings of magnetic north, this accelerated drift has captured the attention of scientists.
So, uh, who is keeping tabs on this?
The World Magnetic Model (WMM), a map of Earth's shifting magnetic dynamics generated by an international team of scientists, was originally scheduled for its five-year update in 2020. But the pole's unusual behavior has already prompted scientists to issue an early update to the WMM.
The patch was released Monday, after a delay caused by the recent US government shutdown that affected agencies such as the National Oceanic and Atmospheric Administration (NOAA), a partner on the WMM. The shutdown caused the update to be pushed back from its planned January 15 release date.
Is the pole acting up?
It's normal for the north and south magnetic poles to wander due to forces in the interior of the planet. But the recent acceleration of the magnetic north pole—which is distinct from the geographic North Pole that is fixed in the Arctic Ocean—suggests something more consequential may be at work.
Why is it changing so fast?
There are multiple theories about the magnetic north pole's recent acceleration, and it will require more research and observations to be sure.
"The difficulty is that we don't have a way to directly observe what is happening in the Earth's core so we have to make a lot of assumptions," Arnaud Chulliat, a geomagnetist at the University of Colorado Boulder and NOAA who works on the WMM, told Motherboard.
A 2016 study in Nature suggested that jet streams located deep in Earth's iron core are weakening magnetic forces under Canada, causing the pole to drift toward stronger forces in Siberia.
Other studies have proposed that Earth may be in the early stages of a magnetic pole reversal. These events occur when the north and south magnetic poles trade places. Scientists can track when the poles swapped in the past from the magnetic signatures in old rocks. The process occurs every 250,000 years on average, but the periods between reversals are irregular. For instance, the last one happened 780,000 years ago.
Not really. The pole's odd acceleration does have some near-term consequences for our navigational systems. Accurate measurements of Earth's magnetic field are integral to many forms of human transportation, including air traffic control and compass-based systems.
Airport runways are named after their alignment with magnetic north, for instance, so occasionally they have to be renamed to reflect the wandering pole's location (this happened in Fairbanks, Alaska, in 2009).
The newly released WMM will be incorporated into magnetic-based navigation systems, and will mostly benefit people in Arctic regions, where the errors have the biggest impact.
What happens if the poles are about to reverse?
It normally takes thousands of years for Earth's poles to flip, so even if such a reversal was imminent—which many scientists doubt—it would likely be centuries or millennia before any appreciable changes would occur.
But if it were to happen, it could pose problems for our far-future descendants, assuming they live in a civilization similar to our own. Earth's magnetic field significantly weakens during reversals, allowing higher doses of radiation to reach the planet. This could expose life on Earth to harmful particles and would disrupt electronics both on the ground and in space.
Earth's magnetic field has been weakening in recent decades, but the north pole's shift does not seem to be having a significant impact on that trend.
"[The pole movement] seems to be more of a regional phenomenon originating in the northern polar cap of the Earth's core," Chulliat said. "The decreasing intensity of the magnetic field is a global phenomenon which seems to be related to some larger scale process that's happening below the South Atlantic. I don't think we have evidence that these processes are related, but it's not impossible. That's part of figuring out the puzzle of how the Earth's core works."
So there's no need to panic?
No. Or at least: don't panic about a pole reversal. There are plenty of immediate risks—climate change, for instance—that should take precedence over a distant hypothetical that cannot currently be predicted.
Read More: Scientists Can't Fix Map of Earth's Magnetic Field Thanks to the Government Shutdown
Given that the WMM team is keeping tabs on the poles, and making sure models are up to date, the pole's movement is not likely to be a problem in the years to come.
Yes, it is making a beeline for Siberia. Yes, it's weird. But thanks to the WMM and sophisticated satellite research missions, the short-term effects of this shift are minimal and any long-term problems will happen long after we're long dead anyway.
Tagged:TechearthCanadaARCTICsiberiaNOAAShutdowngeomagnetic reversalgovernment shutdownNorth PoleNavigationgeomagnetismmagnetism