(ANTIMEDIA) Life on Earth would likely not exist without the geomagnetic field that encases the planet. The product of iron convection churning deep within the planet’s outer core, the magnetosphere creates a literal force field that prevents solar winds from breaking down our atmosphere and allowing radioactive particles to besiege the surface. It has functioned in perpetuity for over 3 billion years, but every few hundred thousand years or so, the poles flip, weakening the field and leaving the Earth vulnerable to charged particles. The last magnetic pole flip took place during the Stone Age, 780,000 years ago. New evidence suggests the next reversal may be close.
According to geophysicists, over the last 160 years the strength of the geomagnetic field has declined at an accelerating rate. The most salient example of this weakening is the South Atlantic Anomaly, the name given to a geographic expanse stretching from Zimbabwe to Chile, where the field has grown so weak that satellites are no longer protected from radiation. In 2012, SpaceX’s Dragon spacecraft experienced such extreme disturbance that it had to shut down and reboot.
Recent observatory and satellite data show that a magnetic pole reversal has already occurred beneath Southern Africa. If a compass were burrowed deep below the surface here and pointed north, it would register south.
Numerical simulations show circumstances like the South Atlantic Anomaly appearing just before pole reversals.
This evidence suggests to scientists that the next magnetic field reversal — which is long overdue — could be closer than expected, though the timeframe for that in geological terms is still in thousand-year increments. The poles flipping would not likely portend the apocalypse, but there would be significant global consequences.
According to two geophysicists familiar with the recent observations:
“Such a major change would affect our navigation systems, as well as the transmission of electricity. The spectacle of the northern lights might appear at different latitudes. And because more radiation would reach Earth’s surface under very low field strengths during a global reversal, it also might affect rates of cancer.”