If you’ve been feeling directionless, literally, it’s understandable; after all, north isn’t quite where it used to be. Here’s what’s happened: the magnetic north pole a crucial navigational force is reportedly shifting, and more rapidly than thought earlier.
Drifting aimlessly across the Canadian Arctic since 1831, the pole’s movement was recorded at nine-odd a year till 1980. Then, in 2017, it crossed the international dateline en route to Siberia.
Satellite data, in 2018, showed that the pole had surpassed the model’s predicted area; currently, it’s hurtling towards Russia at a rate of 55 km per year. Noting the surge, scientists have updated the official map of the worlds magnetic field to pinpoint the poles new location.
How does this change things?
The magnetic north pole has always guided navigators, responding to compass needles from virtually every point on the planet.
As per old ships logs, in the last 400 years, the magnetic north pole has hung around northern Canada. Until the 1900s, it moved tens of back and forth, said Ciaran Beggan, a geophysicist at the British Geological Survey in Edinburgh.
Despite the advent of satellite-based GPS, airplanes, militaries, ships still rely on the magnetic north, usually as backup navigation.
But the recent pace has rendered past estimates inaccurate for precise navigation. Hence, scientists have drawn up a new model for reference that accounts for the pole’s “unplanned variations” in the last four years.
It is a rare action, as the Guardian notes, but one many felt was necessary view of the mysterious surge in pace; the action stems mostly from concern for those who navigate in the Arctic regions.
Why is the north pole meandering?
It is universally agreed that this drift is due to subterranean processes in Earth’s iron and nickel-rich core. In fact, the liquid outer core, where the magnetic field is created by virtue of the electric current (created by the heavy metals), keeps it adrift.
The acceleration in the pole’s movement in recent yearsfrom around 9 km/year (1900-1980) to 38 to 50 km/year (1998-2018)has left scientists to speculate on what may have made it pick up pace.
Some surmise that a jet stream of molten liquid is causing turbulence in Earth’s core, pushing the north pole; other schools of thought postulate that the magnetic south and north poles may be reversing positions, like a bar magnet.
The magnetic south pole is moving slower than the north, and scientists agree that Earth’s magnetic field is getting weaker. That’s why it will eventually flip, resulting in north and south poles to change polarity. An area over the South Atlantic has already reversed beneath Earth’s surface, said University of Maryland geophysicist Daniel Lathrop in an interview with Star Tribune.
But it is not a process that will happen overnight. Experts say the event spreads out over a millennium at least. Such pole reversals have happened numerous times in Earth’s past, they claim, although not in the last 780,000 years.
So much for direction!
Besides the north star and migratory birds, this shift poses a grave problem for smartphone maps, consumer electronics, navigation systems relying on compass. But most importantly, it is a matter of utmost priority for international military agencies that use it as a navigation metric in cases of parachute drops, for example.
Therefore, scientists have updated the World Magnetic Model (WMM), a map that tracks the magnetic poles, a year before schedule. The model, commissioned by the US and British militaries and used by Google and Apple’s civilian mapping systems, NASA and NATO alike, is updated every five years.
The WMM was updated last in 2015; the next model was due to be published towards the end of 2019.
However, in view of the unplanned variations, the US National Oceanic and Atmospheric Administration’s National Centers for Environmental Information issued a press release Monday saying, “Scientists have released a new model to more accurately represent the change of the magnetic field between 2015 and now.”
The agency explained that this “out-of-cycle update … will ensure safe navigation for military applications, commercial airlines, search and rescue operations, and others operating around the north pole.”
Will it affect India?
The changes are largely limited to latitudes above 55 degrees. For most Google Maps users below 55 degrees north, the shifting will make no real difference. This includes India, dissected by the Tropic of Cancer (23.5° north of the equator) and extending 37° N.
Overall, this shift is not unusual in the geological scale of events; it is natural for the magnetic field to change continuously. Geophysicist and lead author of the newly issued WMM, Arnaud Chulliat, clarified that GPS isn’t affected because it’s satellite-based.
But it is a curious phenomenon, nonetheless, especially if we are in the throes of a pole reversal right now. It would mean that the WMM may need to be updated at shorter intervals going forward, and the Polaris may no longer serve as a reliable compass.
Prarthana Mitra is a staff writer at Qrius