The movement is caused by liquid iron sloshing around within the planet’s core. Compasses point toward the Magnetic North Pole which has been creeping away from the coast of northern Canada – where it was a century ago – to the middle of the Arctic Ocean, where it is today.
“It’s moving at about 50 km (30 miles) a year. It didn’t move much between 1900 and 1980 but it’s really accelerated in the past 40 years,” Ciaran Beggan, of the British Geological Survey in Edinburgh, told Reuters on Friday, according to CBC Canada.
World Magnetic Model update
The World Magnetic Model (WMM) is a standard model of the core and large-scale crustal magnetic field. It is used extensively for navigation and in attitude and heading reference systems by the UK Ministry of Defence, the US Department of Defense, the North Atlantic Treaty Organization (NATO) and the International Hydrographic Organization.
Updated model coefficients are released at 5-year intervals, with the current model (WMM2015) expiring on December 31, 2019. The next update to the WMM is due in 2020, however, the magnetic field is changing so rapidly that researchers have to fix the model now.
Why does all this even matter?
Besides all the international organizations that rely on the WMM for navigation – ships, aircraft, antennas, drilling equipment, and other devices depend on the WMM to calculate true bearings – as well as people checking Google Maps on their smartphones and other devices.
On January 15, researchers were set to update the WMM because of the magnetic pole moving so quickly. “The error is increasing all the time,” says Arnaud Chulliat, a geomagnetist at the University of Colorado Boulder and the National Oceanic and Atmospheric Administration’s (NOAA’s) National Centers for Environmental Information.
However, because of President Trump’s refusal to open our government for business, the scheduled fix to the model that was due to take place today has been pushed back to January 30 by the partial US government shutdown.
What’s going on deep inside the Earth?
Researchers were able to figure out back in the 1800s that the magnetic North Pole tended to drift a bit. But by the 1990s, the speed of that drift really began to pick up. In 2018, magnetic north skipped over the International Date Line and entered the Eastern Hemisphere.
The unusual movements of the magnetic pole are caused primarily by the Earth’s liquid-iron outer core, known as the core field. The Earth has a solid inner core and liquid outer core, both made mostly of iron. Scientists believe Earth’s core is responsible for the planet’s magnetic field as well as plate tectonics.
Both changes in the liquid outer core affect the magnetic North Pole as well as Earthquakes, with the outer core transmitting seismic waves. The outer core is about 2,200 kilometers (1.367 miles) thick and is made of liquid iron and nickel alloy. The temperature of the outer core nearest the mantle is 4,400 degrees Celsius (7,952 degrees Fahrenheit).
In attempting to understand what is happening, Phil Livermore, a geomagnetist at the University of Leeds, UK, surmised the fast motion of the north magnetic pole could be linked to a high-speed jet of liquid iron beneath Canada. He thinks the jet may be smearing out and weakening the magnetic field beneath Canada
“The location of the north magnetic pole appears to be governed by two large-scale patches of the magnetic field, one beneath Canada and one beneath Siberia,” Livermore said at the American Geophysical Union meeting in Washington D.C. in December. “The Siberian patch is winning the competition.”
