New study finds Earth’s magnetic field that protects life from energetic particles from the sun and cosmic rays, could flip within a human lifetime. It can take just 100 years to flip. Image © ESA
Earth’s magnetic field has flipped – though not overnight – many times throughout the planet’s history. Now according to scientists intensity of Earth’s magnetic field decreasing 10 times faster than normal.
Its dipole magnetic field, like that of a bar magnet, remains about the same intensity for thousands to millions of years.
For incompletely known reasons it occasionally weakens and, presumably over a few thousand years, reverses direction.
Though a magnetic reversal is a major planet-wide event driven by convection in Earth’s iron core, there are no documented catastrophes associated with past reversals, despite much searching in the geologic and biologic record. Today, however, such a reversal could potentially wreak havoc with our electrical grid, generating currents that might take it down.
UC Berkeley graduate student Courtney Sprain, said:
“It’s amazing how rapidly we see that reversal. The paleomagnetic data are very well done. This is one of the best records we have so far of what happens during a reversal and how quickly these reversals can happen.”
source UC Berkeley