Earth’s magnetic field is constantly moving, and because it is used to properly navigate the planet, scientists need to regularly update the World Magnetic Model (WMM) to account for the shifts in the field.
World Magnetic Model
Scientists update the WMM every five years. WMM is behind modern navigation used by Google Maps, planes, and ships in the sea
The National Oceanic and Atmospheric Administration (NOAA) maintains the key role of the WMM in modern navigation. While GPS is helpful for navigation, it has limitations in that it only provides the position. The magnetic field provides the orientation and the direction one is facing.
The U.S. National Geophysical Data Center released the current version of the WMM in 2015. This should mean that an update is not due until next year.
Erratic Behavior Of Earth’s Magnetic Field
For reasons that still baffle scientists, however, the magnetic north pole is acting up. It has been increasingly moving away from Canada and toward Siberia at an erratic rate.
Ciaran Beggan, of the British Geological Survey in Edinburgh, said it moves at about 30 miles per year.
“It didn’t move much between 1900 and 1980 but it’s really accelerated in the past 40 years,” Beggan said.
Earth’s magnetic field is generated by unpredictable changes in molten iron deep at the core of the planet. It is not yet clear what is behind the erratic changes in the magnetic field, but some scientists think it has something to do with high-speed jet of liquid iron underneath Canada.
“The location of the north magnetic pole appears to be governed by two large-scale patches of magnetic field, one beneath Canada and one beneath Siberia. The Siberian patch is winning the competition,” University of Leeds geomagnetist Phil Livermore said at a meeting of the American Geophysical Union in Washington DC last month.
Rapid Changes In Magnetic Field Call For Earlier Revision Of WMM
The magnetic field is changing so fast researchers have to fix the model soon because navigation error is increasing all the time.
The magnetic field’s strange behavior prompted scientists to fix the map earlier. The updated WMM was supposed to be released on Jan. 15, but this was moved to Jan. 30 because of the ongoing government shutdown.