News of how the Earth’s magnetic field might flip has stirred controversy in the past few months. A study by the University of Rochester looked at southern Africa where they observed what is being called the South Atlantic Anomaly.
The lead author of the study published in the Geophysical Research Letters, Vincent Hare, explained what’s happening in the area they have been studying.
“We’ve known for quite some time that the magnetic field has been changing, but we didn’t really know if this was unusual for this region on a longer timescale, or whether it was normal.”
South Atlantic Anomaly
The information from their latest study suggests that the core-mantle boundary in the southern part of Africa might play a crucial role in the reversal of the Earth’s magnetic poles.
The study on the magnetic field of the planet is essential not just because of locating places using the needle points of the compass. It also plays a significant role in protecting the Earth from radiation in space. The last time that the Earth’s magnetic fields switched was 800,000 years ago. However, current data reveals that the strength of the planet’s magnetic field has been weakening faster than expected.
Of all the places on Earth, the area where the planet’s magnetic field is at its weakest, dubbed as the South Atlantic Anomaly, sits in between Chile and Zimbabwe.
Another Rochester professor, Eric Blackman, believes that the South Atlantic Anomaly is the birthplace of the most recent pole reversal, and it will continue to be the site of a magnetic pole flip in the future. Based on their data, there were fluctuations in the magnetic field of the region between 400 to 450 AD, 700 to 750 AD, and 1225 to 1550 AD. The changes in the magnetic field in southern Africa could play an even more significant role in the global magnetic field.
According to the Astrobiology Magazine, the researchers used ancient clay remnants from the early to the late Iron Age in southern Africa. Based on the excavated samples, the researchers made measurements using magnetometers to compile a record of the behavior of the magnetic field.
What Is The Magnetic Field
The magnetic field is in the Earth’s outer core, and it is composed of swirling, liquid iron. Seismological data reveals that the unique region in Africa located 1,800 miles beneath the continent is present in the African Large Low Shear Velocity Province.
— Forbes (@Forbes) March 2, 2018
A weaker magnetic field means electric grid failures, malfunctioning navigation systems, and satellite breakdowns. As for when a flip could happen, researchers have this to say.
“We now know this unusual behavior has occurred at least a couple of times before the past 160 years and is part of a bigger long-term pattern. However, it’s simply too early to say for certain whether this behavior will lead to a full pole reversal.”