Earth magnetic field

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Finding which direction is north with a compass has changed over the years. Not just with the new versions of the compass but also where magnetic north is located. Since 2015, the magnetic north has been traveling towards Siberia, each year it travels more than 30 miles. After a month-long partial government shutdown in the United States, humans have finally caught up with the change. On Monday, scientists released an emergency update to the World Magnetic Model, which is the center point for GPS systems and military navigators. Most of us wouldn’t notice the slight change but those who navigate by precise calculations close to the Arctic would.

Earth’s magnetic field

The north magnetic pole’s change in location suggests something strange and powerful maybe going on beneath the surface of the Earth. Phil Livermore, at the University of Leeds, believes that the only way to truly understand the magnetic pole is to track it. The planet’s magnetic field is created nearly 2,000 miles beneath our feet, in the spinning ball of molten metal that forms the Earth’s core.

When that underground flow changes, it can change the Earth’s magnetic field lines as well as the poles where they connect. Interestingly enough, the magnetic north doesn’t align with geographic north which is the end point of Earth’s rotational axis. It’s constantly moving and records of ancient magnetic fields from rocks show that the poles can even flip. This type of event has only occurred an average of three times every million years.

Constant movement

In 1831, the first expedition to find magnetic north had pinpointed it in the Canadian Arctic. However, by the time the US Army went looking for the pole in the 1940s, it had moved to the northwest 250 miles. It has shifted since 1990 a total of 600 miles and is currently in the center of the Arctic Ocean which is four degrees south of geographic north. However, the south magnetic pole hasn’t mirrored the north’s movements. Its location has remained relatively the same, on the coast of Eastern Antarctica, since 1990. Livermore’s research suggests that the magnetic north’s location could be controlled by two patches of magnetic field beneath Canada and Siberia. He also reported in 2017 that the Canadian patch is weakening which has resulted in liquid iron moving through the Earth’s core. Livermore suggested at a meeting of the American Geophysical Union in December, that the movement below the Arctic may explain the movement of magnetic field lines. The next update of the World Magnetic Model, a mathematical representation of these field lines, wasn’t supposed to happen till 2020 but the Earth had other plans.

New GPS model

Changes in the Arctic were happening a lot faster than scientists had predicted. According to William Brown, a geomagnetic field modeler for the BGS, the difference between the World Magnetic Model and the current location of the north pole had nearly surpassed the limit needed for accurate navigation. Brown and his team in the US were working on an updated model when the government ran out of funding and shut down.

The full version of the model wasn’t available until recently due to the fact that most of the NOAA employees were not able to work till Monday. Some believe that the Earth is about to go through an event called a magnetic field reversal which hasn’t happened in over 780,000 years. However, these recent changes in the north pole may be a sign that this type of event is right around the corner. Livermore doesn’t see this as a sign for bigger events in the future since there’s no evidence to support the claim. Hopefully, we’ll be able to prepare for such an event if one should occur as we continue to track the magnetic field’s progress.