It was a tumultuous year last year, but at least the North is still the North.
Molten iron continues to flow in the same direction deep within our world, generating a magnetic field which protects us from the harmful radiation of the sun. The flow varies from time to time and the magnetic field tilts. 780,000 years ago, the last time this occurred.
Will 2021 be a year in which the north turns south? A weakening of the field is one indicator that Earth could be preparing for a magnetic reversal. Since measurements started in 1840, we know that the Earth’s magnetic field has weakened by around 5 percent per century.
And much of this weakening is related to an oddly faint spot known as the South Atlantic Anomaly between South America and Southern Africa. Over the last 250 years, this patch has evolved, and today the weak field is interfering with satellite technology. So how new is this anomaly? Geologists at the University of Liverpool have shown that the magnetic field has been playing here for millions of years since examining volcanic rocks from the South Atlantic island of St. Helena, indicating that the South Atlantic Anomaly is a long-term fixture, not a warning that the magnetic field of the Planet is about to flip.