New research suggests Earth's magnetic polarity isn't reversing

June 8 (UPI) -- A South Atlantic rapid geomagnetic field decrease known as the South Atlantic Anomaly led to speculation that Earth's magnetic polarity was reversing.

But a new study, published this week in the journal PNAS, suggests the reversal may not be happening after all.

"We have mapped changes in the Earth's magnetic field over the past 9,000 years, and anomalies like the one in the South Atlantic are probably recurring phenomena linked to corresponding variations in the strength of the Earth's magnetic field," lead study author Andreas Nilsson, a geologist at Lund University in Sweden, said in a press release.

Nilsson said that, based on the new modeling, researchers have concluded that Earth is not heading toward a polarity reversal.

Earth's magnetic field is not stable, and polarity reversals where the North and South poles flip has happened on average roughly every 200,000 years.

During the past 180 years, Earth's magnetic field strength has declined by about 10%. The magnetic field protects Earth's atmosphere from being swept away by solar winds.

The results reported in the new study are based on analyzing archaeological artifacts, volcanic samples and sediment drill cores.

According to Nilsson, a new modeling technique that combines data from those samples created one global reconstruction of the magnetic field over 9,000 years, and that led to the conclusion that magnetic polarity is not reversing.