Our planet's protective shell is no longer what it once was. Its magnetic strength has dropped sharply over the last two centuries, and no one knows why.
Concurrently, a worrying soft-spot in the field known as the South Atlantic Anomaly has blistered across the Atlantic ocean, posing a challenge for delicate circuitry aboard orbital satellites.
A magnetic pole reversal is a change in the polarity of the Earth's magnetic field. This has happened at irregular intervals throughout geologic time.
Given our reliance on electronic equipment, which could be vulnerable without a magnetic shield, even a rapid field reversal in the near future would leave us vulnerable.
The last time such a tremendous event occurred, 42,000 years ago, high-speed charged particles swept through Earth's atmosphere.
Based on replicated anomalies, scientists predict the South Atlantic Anomaly will disappear within 300 years and that Earth is not moving towards a polarity reversal.
The South Atlantic soft-spot isn't unusual when viewed over thousands of years. Similar geological changes began approximately 1600 BCE and lasted 1,300 years.
That's good news in some ways. However, we have no idea what such a large geological activity will look like on the scale of a human lifetime.