What fast-moving magnetic north pole means for the world
Scientists say the pole is shifting towards Russia at rate of around 34 miles a year
Earth’s magnetic north pole is moving faster than at any other time since records began - and technology is struggling to keep up, scientists are warning.
Used by navigators for millennia, the magnetic north pole is the point in the northern hemisphere at which the planet’s magnetic field points vertically downwards. A magnetic compass points to this pole, which is not the same as the geographic North Pole - the fixed point at which the lines of longitude meet at the top of the world.
By contrast, the magnetic pole naturally shifts around, and is currently doing so at a surprising rate, causing potential problems for mapping and geolocation technology.
This drift is the result of processes taking place at the centre of the Earth. “Molten iron and nickel slosh and spin in the planet’s core, essentially serving as a metallic conductor for Earth’s magnetic field,” says NPR.
The “changes in that fluid flow lead to changes in the magnetic field”, and can result in the pole shifting geographically, the US-based news site explains.
The first measurement of the magnetic pole was taken in 1831 in the Canadian Arctic, The Guardian reports. Since then, it has moved about 1,400 miles (2,250km) toward Siberia.
As a result of this drift, the US National Oceanic and Atmospheric Administration’s (NOAA) World Magnetic Model (WMM) - a mathematical representation of the magnetic field - slowly falls out of sync. Until now, the model has been updated every five years, with the last update in 2015.
Accurate readings of the magnetic north pole by the WMM are vital for military, undersea and aircraft navigation, commercial airlines, search-and-rescue operations and other projects circling the North Pole, says Live Science.
Organisations including Nasa and the US Forest Service also rely on the model for surveying and mapping, and satellite and antenna tracking.
“Even smartphone and consumer electronics companies need an accurate model so that they can provide users with up-to-date maps and compass applications,” says the site, which adds that GPS is not affected because it is satellite-based.
However, since 2000 the rate at which the magnetic north pole is moving has jumped from about nine miles (14.5km) to 34 miles (55km) a year.
These “unplanned variations”, as the NOAA describes them, has prompted to release of an early WMM update this week, nearly a year ahead of schedule.
“It’s not the fact that the pole is moving that is a problem, it’s the fact that it’s accelerating at this rate,” said William Brown, a geophysicist at the British Geological Survey. “The more acceleration or deceleration there is, the harder to predict where the thing is going to be.”
Indeed, National Geographic reports that rocks “hold geologic maps of even weirder movements of the magnetic poles, suggesting that in the last 20 million years, magnetic north and south have flipped places multiple times” - something that appears to happen roughly every 200,000 to 300,000 years.
However, experts say that the latest acceleration toward Russia does not necessarily indicate that another reversal is in the pipeline.
“And even if there was a reversal, geological records show these things tend to take a few thousand years, at the very least,” Ciaran Beggan, a geophysicist with the British Geological Survey, told the magazine.