I remember a professor mentioning the possibility of magnetic pole reversal being a very scary thing, almost as an aside. I don't even remember what class it was now, but he made a joke of it. At that time, some 30 years ago, climate change seemed like a much scarier and more immediate threat.
But I may have to re-evaluate that.
As you may know, the Earth's magnetic poles have reversed many times before, not on a regular basis, but averaging about 500,000 years between the reversals. The last reversal was 780,000 years ago.
Scientists aren't really sure why it happens, though some theories have cropped up lately, like this "lava lamp" theory. But it's inarguable that the poles are weakening and shifting.
And what that means for the seven billion people now on the planet? Nothing good:
Daniel Baker, director of the Laboratory for Atmospheric and Space Physics at the University of Colorado, Boulder, one of the world’s experts on how cosmic radiation affects the Earth, fears that parts of the planet will become uninhabitable during a reversal. The dangers: devastating streams of particles from the sun, galactic cosmic rays, and enhanced ultraviolet B rays from a radiation-damaged ozone layer, to name just a few of the invisible forces that could harm or kill living creatures.
How bad could it be? Scientists have never established a link between previous pole reversals and catastrophes like mass extinctions. But the world of today is not the world of 780,000 years ago, when the poles last reversed, or even 40,000 years ago, when they tried to. Today, there are nearly 7.6 billion people on Earth, twice as many as in 1970. We have drastically changed the chemistry of the atmosphere and the ocean with our activities, impairing the life support system of the planet. Humans have built huge cities, industries and networks of roads, slicing up access to safer living spaces for many other creatures. We have pushed perhaps a third of all known species toward extinction and have imperiled the habitats of many more. Add cosmic and ultraviolet radiation to this mix, and the consequences for life on Earth could be ruinous.
And the perils are not just biological. The vast cyber-electric cocoon that has become the central processing system of modern civilization is in grave danger. Solar energetic particles can rip through the sensitive miniature electronics of the growing number of satellites circling the Earth, badly damaging them. The satellite timing systems that govern electric grids would be likely to fail. The grid’s transformers could be torched en masse. Because grids are so tightly coupled with each other, failure would race across the globe, causing a domino run of blackouts that could last for decades.
Yikes. Granted, there's no way to know if it's happening this year or in ten years...or even 50. But it's hard not to feel like this is just another horrible apocalyptic event to expect in a series of just horrible, horrible events we've had in the last few years.