This article and many others like it describe a phenomenon where the Earth’s magnetic poles occasionally switch directions. The key ideas seem to be:
Earth’s magnetic poles occasionally switch places.
This probably happens on a semi-regular basis, and according to our best guess at the schedule, we’re long overdue for a switch right now.
The magnetic north pole has been moving South much faster than normal recently (25 mi/year).
We don’t know exactly what happens during a switch, but it’s probably not great.
The main concern seems to be that the Earth’s magnetic field is what’s responsible for deflecting/weakening a lot of incoming radiation, but the magnetic field gets a lot weaker during a switching event. Then again, the article linked above suggests that the period is about 300,000 years, which is far shorter than the length of our evolutionary history. That puts a bound on how bad it can be.
Nonetheless, this all somewhat concerning to me. Who are the relevant authority figures on the subject? How worried are they that we might be on the brink of some kind of extinction event? How worried are they about the interaction of such an event with everyday electronics? Do they make any recommendations for how individual people can prepare themselves for a potential switch? How about for society?
There’s evidence to be had in the fact that, though it’s been known for a long time, it’s not a big field of study with clear experts. From very light googling, it seems likely to happen over hundreds or thousands of years, which puts it pretty far down the list of x-risk worries IMO.
This is true. It’s only a mild comfort to me, though, since I don’t have too much faith in humanity’s ability to conjure up fields of study for important problems. But I do have some faith.
Also true. This makes me update away from “we might wake up dead tomorrow” and towards “the future might be pretty odd, like maybe we’ll all wear radiation suits when we’re outside for a few generations”.
3. is no cause for concern at all. 2. (‘overdue’) presumes some knowledge of mechanism, which I don’t have. Roughly speaking it’s a 1 in 300,000 risk each year and not extinction level. Additionally, we can easily employ radiation poisoning prophylactics if there’s some long-lasting decreased shielding (which I highly doubt—there’s less shielding at the poles, right, but no big deal—it’s not as though the field temporarily disappears completely!)
Am I misunderstanding, or is this an argument from ignorance? The article says we’re overdue; that makes it sound like someone has an idea of what the mechanism is, and that person is saying that according to their model, we’re overdue. Actually, come to think of it, “overdue” might not imply knowledge of a mechanism at all! Maybe we simply have good reason to believe that this has happened about every 300,000 years for ages, and conclude that “we’re overdue” is a good guess.
How do you know?