That’s exactly what I said in both Not by Fire but by Ice and Magnetic Reversals and Evolutionary Leaps. Now here’s a video exploring that very question.
This video by Anton Petrov explores the Laschamp magnetic reversal of 42,000 years ago, which lasted anywhere from 400 years to 1,000 years.
Petrov asserts that magnetic reversals occur every 300,000 years or so but then gives a nod to magnetic excursions, which take place much more often.
(I’m inclined to think magnetic excursions take place about every 11,500 years. And that they do it in sync with precession of the equinoxes.)
During an excursion, the earth’s magnetic-field strength declines precipitously, which allows carbon-14 and beryllium-10 to bombard our planet, says Petrov.
(I talk about that beryllium-10 in both “Not by Fire but by Ice” and “Magnetic Reversals and Evolutionary Leaps,” because I think the increase in radioactive materials inundating our atmosphere leads not only to extinctions, but to an increase in mutations and thence to evolutionary leaps.)
According to Petrov, the earth’s magnetic-field strength at that time declined to only five to ten percent of what we have today (I agree), and lasted for several centuries. Now, pointing to what is known as the South Atlantic Anomaly where magnetic field-strength has declined, he sees a similar thing happening on earth today.
That decline, which is well-documented, has already been enough to have destroyed a Japanese satellite.
“Even flying in an airplane is going to become extremely dangerous.”
“We know, without the magnetic field to protect our planet, that the satellite technology and a lot of aerospace industries are going to be basically impossible to maintain,” says Petrov. “Even flying in an airplane is going to become extremely dangerous.”
Petrov then ties the magnetic excursion of 42,000 years ago to the extinction of several megafauna (large animal) species in Australia at the time, pointing to the huge increase in ultraviolet UV) light, which, he says, is damaging to many kinds of cells.
The upshot of all this?
Maybe, just maybe, we are now headed for an excursion event, warns Petrov.
“This is perhaps something we might want to start preparing for – just in case.”
I agree that we should start preparing.
Think about it. How could a dramatic increase in radioactive materials raining down on our planet NOT lead to extinctions?
How could a dramatic increase in radioactivity bombarding our bodies – and the bodies of all living species – NOT lead to mutations and evolutionary leaps?
Trouble is, I’m not exactly sure how we begin preparing.
What does Wikipedia have to say about this?
According to Wikipedia, the Laschamps excursion occurred 41,400 (±2,000) years ago during the end of the Last Glacial Period; it was first recognised from a geomagnetic excursion discovered c. 1969 in the Laschamps lava flows in the Clermont-Ferrand district of France.
The magnetic excursion has since been demonstrated in geological archives from many parts of the world. The magnetic field was reversed for approximately 440 years, with the transition from the normal field lasting approximately 250 years. The reversed field was 75% weaker, whereas the strength dropped to only 5% of the current strength during the transition. This reduction in geomagnetic field strength resulted in more cosmic rays reaching the Earth, causing greater production of the cosmogenic isotopes beryllium 10 and carbon 14.
The Australian Research Council is funding research to analyze a kauri tree uncovered in New Zealand in 2019. According to its carbon-dating, the tree was alive during the event (41,000–42,500 years ago).
The geomagnetic field was at low levels from 42,200–41,500 years ago. This period of low magnetic field has been termed the Adams Event or Adams Transitional Geomagnetic Event, a tribute to science fiction writer Douglas Adams, who wrote in The Hitchhiker’s Guide to the Galaxy that “42” was the answer to life, the universe, and everything. During this period, Earth’s magnetic field dropped to below 6% of the current level, Carbon 14 production increased, ozone levels decreased, and atmospheric circulation changed. This loss of the geomagnetic shield was also claimed to have caused the extinction of Australian megafauna, the extinction of the Neanderthals, and the appearance of cave art. However, the lack of corroborating evidence of a causal link between the Laschamps event and population bottlenecks of many megafauna species and the relatively moderate radio-isotopic changes during the event have cast significant doubt on the real impact of the Laschamps event on global environmental changes 
Thanks to Michael Gershman for this video
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May 14, 2021 at 10:30AM