And thanks to the political storm in Washington, scientists have been unable to post an emergency update of the World Magnetic Model, which cellphone GPS systems and military navigators use to orient themselves. Roughly half the employees at the National Oceanic and Atmospheric Administration, which hosts the model and publishes related software, are furloughed because of the partial government shutdown, now in its 27th day.
As reported in Nature, the updated model was supposed to be released this week. It would have been a minor change for most of us — the discrepancy between the model and the North Pole’s new location is measurable only to people trying to navigate precisely and at extremely high latitudes.
As long as NOAA staff are absent and the agency’s website is dormant, the world must go on navigating by the old model — which grows slightly more inaccurate each day.
The exact cause of all this geomagnetic commotion remains a mystery.
Scientists know the movement of molten iron in the Earth’s interior generates a magnetic field, and that field fluctuates according to the behavior of those flows. Consequently, the planet’s magnetic poles don’t exactly align with its geographic poles (the end points of the Earth’s rotational axis), and the location of these poles can change without warning. Records of ancient magnetism buried in million- and billion-year-old rocks suggest that sometimes Earth’s magnetic field even flips; the South Pole has been in the Arctic, while the North Pole was with the penguins.
When British Royal Navy explorer James Clark Ross went looking for the North Pole in 1831, he found it in the Canadian Arctic. A Cold War-era U.S. expedition pinpointed the pole 250 miles to the northwest. Since 1990, it has moved a whopping 600 miles, and last year it crossed the international date line into the Eastern Hemisphere. (The South Pole has stayed comparatively stable.)
The World Magnetic Model is updated every five years to accommodate these shifts. The next one wasn’t scheduled until 2020.
However, the network of magnetometers and satellites that track the magnetic field began to send strange signals. The movement of the North Pole was accelerating unpredictably, and the 2015 version of the World Magnetic Model couldn’t keep up. Navigation tools that rely on magnetic fields for orientation were slowly drifting off target. So the U.S. military, which funds research for the model, requested an unprecedented early review.
Research from University of Leeds geophysicist Phil Livermore suggests the pole’s location is controlled by two patches of magnetic field, one beneath northern Canada and another below Siberia. In 2017, he reported the detection of a jet of liquid iron that seemed to be weakening the Canadian patch.
This may be what’s causing the pole to shift so quickly, he said in a presentation at the fall meeting of the American Geophysical Union in December. He has not yet published that research in a peer-reviewed journal.
“It’s very hard to know what’s going on because it’s going on 3,000 kilometers beneath our feet,” Livermore said. “And there’s solid rock in the way.”
By last summer, it became clear that the discrepancy between the World Magnetic Model and the real-time location of the magnetic North Pole was about to exceed the threshold needed for accurate navigation. Researchers for NOAA and the British Geological Survey, who collaborate to produce the model, spent several months analyzing the rapid change. Just before Christmas, the two agencies reached an agreement on a new model and were preparing to publish their updated version.
And then the government shut down.
The British agency was able to publish some parts of the new model on its site, said William Brown, a geophysicist with the British Geological Survey who works on the World Magnetic Model.
NOAA is responsible for hosting the model and making it available for public use, he said. “All of that is currently unavailable.”
Some have speculated that Earth is overdue for another magnetic field reversal. The geologic record suggests these events happen three times every million years. The last was 780,000 years ago, around the time humans started to evolve. (A note to conspiracy theorists: These events are almost certainly unrelated.)
“There’s no evidence for that,” Livermore said, but recent changes at the North Pole “might indicate that something abnormal is happening.”
The only way to find out is to continue tracking the Earth’s magnetic field and attempt to interpret the signals it sends, Livermore said. He finds the uncertainty thrilling.
“We’ve sent robots to Mars and put people on the moon, but we don’t really have an idea of what’s going on in the interior of our planet,” he said. “It’s really an exploration into the unknown.”