A team from the University of California, Berkeley has discovered that the Earth’s magnetic field may flip sooner than previously expected. But don’t worry, it’s not time to buy a new compass just yet.
The team measured magnetic field alignments from ancient lake sediments near Rome, Italy and found that the last reversal happened 786,000 years ago over a period of less than 100 years. “It’s amazing how rapidly we see that reversal,” said UC Berkeley’s Courtney Sprain. “This is one of the best records we have so far of what happens during a reversal and how quickly these reversals can happen.” Combined with evidence that the intensity of the Earth’s magnetic field is currently decreasing 10 times faster than normal, this may mean that a flip could be happening within a few thousand years, researchers say. A magnetic reversal is a major planet-wide event driven by movement in the Earth’s iron core.
The Earth’s magnetic field is dipolar like a common bar magnet and has flipped many times over the course of history. There are no documented catastrophes associated with past reversals. However, a reversal could potentially cause problems with the electrical grid and satellite networks. (Source : BBC Focus Science and Technology)