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Magnetic north isn’t even close to where it used to be

Author: Robby Berman / Source: Big Think

  • Magnetic north has recently been moving north from Canada to Russia in a cold hurry.
  • It’s moving about 33 miles a year instead of the usual 7 miles.
  • World navigation models had to updated ahead of schedule to catch up with it.

If you’re reading this as you travel the arctic, odds are you’re probably already a bit confused.

Your compass has been, well, strange, lately. That’s because magnetic north has been moving. Quickly. It’s never been stationary, but recently it’s been moving around 485 feet northward toward Siberia every day. That’s about 33 miles per year, as opposed to the average 7 miles a year between 1831 and the 1990s, when its pace quickened.

Fortunately, experts say that if you’re south of the 55th parallel, you won’t notice much of a difference. However, for national defense agencies, commercial airlines, and others that rely on knowing what their compasses are pointing at, it’s a much bigger deal. That’s why the World Magnetic Model — a set of online reference calculators, software, and technical details — had to be updated recently ahead of schedule instead of waiting for the next planned revision in 2020.

North, north, and north

Image source: Pyty / Shutterstock

There are actually three flavors of north, and they’re all in different places.

  • Magnetic north — is defined as the location on the Earth’s surface where all of its magnetic lines point straight downward. If you look at a compass while you’re there, the needle attempts to dip down; that’s why it’s also called the “dip pole.” Magnetic north is always on the move in response to the constant motion of electrical charges in the Earth’s liquid outer mantle, which produces Earth’s magnetic field.
  • Geomagnetic north — is the northern focus of the Earth’s magnetosphere, up in the stratosphere. It moves, too, but not nearly as much, since shifts in the Earth’s magnetic field are…

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