One day in 1905, the French geophysicist Bernard Brunhes brought back to his lab some rocks he’d unearthed from a freshly cut road near the village of Pont Farin.
When he analyzed their magnetic properties, he was astonished at what they showed: Millions of years ago, the Earth’s magnetic poles had been on the opposite sides of the planet. North was south and south was north. The discovery spoke of planetary anarchy. Scientists had no way to explain it.
Today, we know that the poles have changed places hundreds of times, most recently 780,000 years ago.
Sometimes, the poles try to reverse positions but then snap back into place, in what is called an excursion. The last time was about 40,000 years ago.
We also know that when they flip next time, the consequences for the electrical and electronic infrastructure that runs modern civilization will be dire. The question is when that will happen.
In the past few decades, geophysicists have tried to answer that question through satellite imagery and math. They have figured out how to peer deep inside the Earth, to the edge of the molten, metallic core where the magnetic field is continually being generated. It turns out that the dipole — the orderly two-pole magnetic field our compasses respond to — is under attack from within.
The latest satellite data, from the European Space Agency’s Swarm trio, which began reporting in 2014, show that a battle is raging at the edge of the core. Like factions planning a coup, swirling clusters of molten iron and nickel are gathering strength and draining energy from the dipole.
The north magnetic pole is on the run, a sign of enhanced turbulence and unpredictability. A cabal in the Southern Hemisphere has already gained the upper hand over about a fifth of the Earth’s surface. A revolution is shaping up.
If these magnetic blocs gain enough strength and weaken the dipole even more, they will force the north and south poles to switch places as they strive to regain supremacy.
Scientists can’t say for sure that is happening now — the dipole could beat back the interlopers. But they can say that the phenomenon is intensifying and that they can’t rule out the possibility that a reversal is beginning.
The Earth’s magnetic field protects our planet from dangerous solar and cosmic rays, like a giant shield. As the poles switch places (or try to), that shield is weakened; scientists estimate that it could waste away to as little as a tenth of its usual force.
The shield could be compromised for centuries while the poles move, allowing malevolent radiation closer to the surface of the planet for that whole time. Already, changes within the Earth have weakened the field over the South Atlantic so much that satellites exposed to the resulting radiation have experienced memory failure.
That radiation isn’t hitting the surface yet. But at some point, when the magnetic field has dwindled enough, it could be a different story. 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.
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.
2 comments:
FYI: this story seems almost two years old.
The same story is at StrangeSounds.org and has comments starting in February 2018(!).
Watch out for StrangeSounds.org stories; of late, sadly, they have started to recycle old stories, yet putting them on their home page with current dates.
If I can post links in the comment, this is the link to the StrangeSounds story (current date with 2018 comments):
https://strangesounds.org/2019/10/the-magnetic-field-is-shifting-the-poles-are-flipping-and-this-could-get-really-bad.html
You're right, and they aren;t the only site to do this - one other site I frequent has been posting old stories as well and I have to always check. However at least with this one, its still germane as the poles have continued with this movement
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