The ‘Out of Africa’ Theory That Explains Why the Earth’s Magnetic Poles May Soon Switch

8 February 2017

 - The Earth is blanketed by a magnetic field. Every so often – on the order of several hundred thousand years or so – the magnetic field has flipped. North has pointed south, and vice versa. And when the field flips it also tends to become very weak.

What currently has geophysicists like us abuzz is the realization that the strength of Earth’s magnetic field has been decreasing for the last 160 years at an alarming rate. This collapse is centered in a huge expanse of the Southern Hemisphere, extending from Zimbabwe to Chile, known as the South Atlantic Anomaly. 

The magnetic field strength is so weak there that it’s a hazard for satellites that orbit above the region – the field no longer protects them from radiation which interferes with satellite electronics.