Study: South Atlantic magnetic field anomaly existed for 11 million years

Written by Amy Woodyatt on July 21, 2020. Posted in Current News

Earth’s magnetic poles, which serve as the foundation of 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 took place 770,000 years ago, but if a reversal happened during our lifetime, it could impact navigation, satellites and communications.

The Earth’s magnetic field protects our atmosphere from solar wind, which is a stream of charged particles coming from the sun. The geomagnetic field is not stable in strength and direction, and does have the ability to flip or reverse itself.

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 research published Monday, scientists from the University of Liverpool said they have proof that today’s South Atlantic Anomaly is a recurring feature, and is unlikely to be linked to any impending reversal of the Earth’s magnetic field.

Researchers analyzed igneous rocks from Saint Helena island, a tiny volcanic island located right in the middle of the South Atlantic and lies in the South Atlantic Anomaly.

Geomagnetic records from the rocks, which covered 34 volcanic eruptions from the area between 8 and 11 million years ago, revealed that the magnetic field for Saint Helena often pointed far from the North Pole — just as it does now.

Largely generated by an ocean of superheated liquid iron in Earth’s core, the magnetic field creates electrical 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 region dating back millions of years,” saidlead author Yael Engbers, a doctoral student at the University of Liverpool, in a statement. “It reveals that the anomaly in the magnetic field in the South Atlantic is not a one-off; similar anomalies existed eight to 11 million years ago.”

Read more at edition.cnn.com

***

PRINCIPIA SCIENTIFIC INTERNATIONAL, legally registered in the UK as a company incorporated for charitable purposes. Head Office: 27 Old Gloucester Street, London WC1N 3AX. 

Please DONATE TODAY To Help Our Non-Profit Mission To Defend The Scientific Method.

Trackback from your site.