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Earth’s Magnetic North Pole Shifts toward Siberia

02/05/2019

National Centers for Environmental Information (NCEI) scientists have updated the world magnetic model (WMM) mid-cycle, as Earth’s northern magnetic pole has begun shifting quickly away from the Canadian Arctic and toward Siberia, an NCEI report said this week. The new WMM more accurately represents the change of the magnetic field since 2015. The alteration could have an impact on government, industry, and consumer electronics.

“Due to unplanned variations in the Arctic region, scientists have released a new model to more accurately represent the change of the magnetic field,” the report said, noting that updated versions of the WMM are typically released every 5 years. This update comes about 1 year early.

“This out-of-cycle update before next year’s official release of WMM 2020 will ensure safe navigation for military applications, commercial airlines, search and rescue operations, and others operating around the North Pole,” said NCEI, which is part of the National Oceanographic and Atmospheric Administration (NOAA). “Organizations such as NASA, the Federal Aviation Administration, US Forest Service, and many more use this technology. The military uses the WMM for undersea and aircraft navigation, parachute deployment, and more.”

Other governmental entities use the technology for surveying and mapping, satellite/antenna tracking, and air traffic management. Smartphone and consumer electronics companies also rely on the WMM to provide consumers with accurate compass apps, maps, and GPS services.

Airport runways may be the most visible example of a navigation aid updated to match shifts in Earth’s magnetic field. Airports around the country use the data to give runways numerical names, which pilots refer to on the ground. The declination has changed slightly more than 2.5° over the past 2 decades or so. Compasses use declination — the difference between true north and where a compass points — to help correct navigation systems for a wide variety of uses.

As Earth's magnetic field evolves between the 5-year release schedule of the WMM, these predicted values can become off as the rate of change in Earth's magnetic field evolves due to unpredictable flows in Earth’s core. The NCEI report said Earth’s north polar region is experiencing one of these erratic changes. 

DXer and Contester Frank Donovan, W3LPL, said the slowly drifting geomagnetic north pole has much greater significance to DXers and contesters because the northern auroral oval — which greatly affects HF propagation over the north Atlantic and north Pacific Oceans — is closely centered on the geomagnetic north pole and not on the magnetic — or dip — north pole discussed in the NCEI report.

“The geomagnetic north pole has been drifting generally northward at only about 3 miles per year,” Donovan pointed out. “The location of the magnetic north pole is important to navigation but of relatively little importance to space-based phenomena such as HF ionospheric propagation.” — Thanks to NOAA-NCEI 



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