Strange behavior in the South Atlantic’s magnetic field dates back 11 million years, and it’s unlikely to be linked to an imminent reversal of Earth’s magnetic field, the researchers found.
The Earth’s magnetic poles, which serve as the basis for our navigation, are actively moving. The magnetic field reverses its polarity every several hundred thousand years, where the magnetic North Pole resides at the geographic South Pole. The last reversal was 770,000 years ago, but if a reversal were to occur in our lifetime, it could impact navigation, satellites, and communications.
The puzzling behavior in the South Atlantic region is causing technical disruptions in satellites and spacecraft orbiting the Earth, which has left experts baffled.
The field is the subject of debate among scientists, some of whom are wondering where it came from, and whether it could signal the total weakening of the field, and even an upcoming pole reversal.
The South Atlantic anomaly is an area stretching from Africa to South America where the Earth’s magnetic field is gradually weakening.
Here’s the good news: In a study released Monday, scientists at the University of Liverpool said they had evidence that today’s South Atlantic anomaly is a recurring feature and that it is unlikely ‘it is linked to an imminent reversal of the Earth’s magnetic field.
The researchers analyzed the igneous rocks of the island of Saint Helena, a tiny volcanic island located in the middle of the South Atlantic and located in the South Atlantic anomaly.
Geomagnetic records from the rocks, which covered 34 volcanic eruptions in the region 8 to 11 million years ago, have revealed that Saint Helena’s magnetic field often pointed far from the North Pole – just as it does now.
Largely generated by an ocean of superheated liquid iron in the Earth’s core, the magnetic field creates electric currents, which in turn generate our changing electromagnetic field. The field, which is not static, varies in both strength and direction, according to the European Space Agency.
“Our study provides the first long-term analysis of the magnetic field in this million-year-old region,” said lead author Yael Engbers, a PhD student at the University of Liverpool, in a statement. “It reveals that the magnetic field anomaly in the South Atlantic is not a point; similar anomalies existed eight to 11 million years ago. ”
“This is the first time that the irregular behavior of the geomagnetic field in the South Atlantic region has been manifested over such a long period,” Engbers said in the statement. “This suggests that the South Atlantic anomaly is a recurring feature and probably not a sign of an imminent reversal.
“It also supports previous studies that suggest a link between the South Atlantic anomaly and abnormal seismic features in the lower mantle and outer core,” Engbers added. “This brings us closer to directly relating the behavior of the geomagnetic field to characteristics of the Earth’s interior. “
CNN’s Ashley Strickland contributed to this report.