Earth’s magnetic poles could flip much faster than previously thought

September 22, 2018
Magnetic Field - Aurora

Magnets, how do they work? Modern day philosophers Shaggy 2 Dope and Violent J of the Insane Clown Posse were mercilessly mocked for that line back when their song “Miracles” came out in 2010. Yeah, that song is about as goofy as it gets, but here’s the thing: we don’t actually know how magnetism works. We know what makes certain elements magnetic, we know how to magnetize objects, we can measure the strength of a magnetic field, and we can accurately predict what magnets will do, but as to why and how the magnetic force attracts and repels objects, the best answer we have so far is “it just does.” Case in point: the famous scientist Richard Feynman was asked why magnets attract and repel each other and responded with a tirade about broken hips, drunk husbands, and why ice is slippery for 8 minutes, in order to explain why the only reasonable answer is “it just does.”

Magnetism is a constant part of our daily lives in more ways than just hanging things on refrigerators. In fact, if it weren’t for magnetism, we wouldn’t even be here. The magnetic field of the earth, likely generated by the spinning molten metal core of the planet, ripples out from the poles and acts as a shield that protects the earth from solar winds and cosmic rays which would otherwise scorch all life on earth. So magnetism keeps us alive and we’re incapable of understanding it. That’s slightly unsettling, but even more unsettling is that we’re constantly realizing we know even less than we thought, even on a predictive level. We’ve known for some time that it’s possible for the magnetic poles to reverse. This was discovered in 1906 when rocks were discovered that were magnetized in the opposite direction of what was expected. Since then, we’ve assumed that this process occurs rarely and slowly. However, a new study has found that magnetic field reversals can occur much quicker than previously thought.

Geophysicist Andrew Roberts and a team from the Australian National University studied a 107 thousand-year-old stalagmite found in a cave in China, made up of large quantities of magnetite that provided a detailed look at the magnetic history of earth for the last 107 thousand years. They found that there have been periods of magnetic pole reversal, where north became south and south became north, that lasted for only a few centuries. According to Roberts, this suggests that the process of the reversal was incredibly fast:

“The record provides important insights into ancient magnetic field behaviour, which has turned out to vary much more rapidly than previously thought.”

Which means that there might not be much warning should the magnetic field decide to flip again, an event which, by the way, we’re overdue for. Should the magnetic field flip, it could cause a catastrophic failure of much of the technology that makes modern society work. It seems that the magnetic field reversals occur when the magnetic field is weakened. Although it is currently still strong, it does seem like the magnetic field is in a period of weakening.

It’s good that scientists are discovering more about yet another global threat, but really, even if they could predict it, is a pole reversal happens that fast, what could we really do about it? Would we pull our satellites out of the sky and re-calibrate them?  Would we make emergency updates to our infrastructure? The amount of pot holes I hit yesterday suggests we’d probably just shrug and say “well, it is what it is.”