The flipping of the Earth’s magnetic poles combined with declining solar activity 42,000 years ago could have created a horrific environment that may have played a role in major events ranging from the extinction of megafauna to the end of NeanderthalsResearchers say.
The Earth’s magnetic field It acts as a protective shield against harmful cosmic radiation, but when the poles change, as has happened many times in the past, the protective shield weakens greatly and leaves the planet exposed to high-energy particles.
A temporary reversal of the poles, known as the Laschamps Flight, occurred 42,000 years ago and lasted about 1,000 years. The researchers said previous work found little evidence that the event had a profound effect on the planet, possibly because the focus was not on the period when the poles were actually shifting.
Currently Scientists say the solstice, along with a period of low solar activity, may have been behind a wide range of climate and environmental phenomena with dramatic repercussions. “Maybe it looked like the end of days,” said Professor Chris Tierney of the University of New South Wales and co-author of the study.
Collectively, the team called this period the “Adams Event,” a reference to Douglas Adams, author of The Hitchhiker’s Guide to the Galaxy Where it has been said that 42 is “the answer to the ultimate question of life, the universe and everything.”
writing In the journal ScienceTierney and colleagues describe how they conducted radiocarbon analyzes of ancient korean rings preserved in wetlands north of New Zealand, some of which were more than 42,000 years old.
This allowed them to track the rise in carbon-14 levels in the atmosphere over time caused by increased levels of high-energy cosmic radiation reaching Earth during the course of La Champagne’s flight. As a result, they were able to date the changes in the atmosphere in more detail than previous records, such as mineral deposits, had provided.
Then they examined numerous records and materials from around the world, including from lake and ice, and found that a host of major environmental changes occurred around the same time that carbon 14 levels were peaking.
“We see this massive growth of ice cover over North America … we see tropical rain belts in the western Pacific shifting dramatically at that point, and then also wind belts in the Southern Ocean and droughts in Australia,” said Turney.
The researchers also used a model to study how the chemistry of the atmosphere could change if the Earth’s magnetic field was lost and there was a prolonged period of low solar activity, which would have reduced the Earth’s protection from cosmic radiation. Core glacial records indicate such dips in solar activity, known as the “solar minimum”, which coincided with the voyage of Champs.
The results reveal that changes in the atmosphere may lead to massive climate shifts, electrical storms, and widespread colored auroras.
In addition to environmental changes that could potentially accelerate the growth of ice sheets and contribute to the extinction of the Australian megafauna, the team suggests that it could also be linked to the appearance of handprints with red ocher, and the suggestion is that humans may have used the dye as a sunscreen against the increased levels of UV rays. That strikes the Earth as a result of depletion of the ozone layer.
They also suggest that the high use of caves by our ancestors around this time, combined with the height of cave art, may be due to the fact that underground spaces provide shelter from the harsh conditions. Tourney said the situation may have boosted the competition as well, which could contribute to the end of Neanderthals.
Earth’s magnetic field has weakened by about 9% over the past 170 years, and researchers say another heart might be on paper. Such a situation could have a major impact, not least of which is the destruction of electrical and space networks.
Richard Horn, head of space, weather and atmosphere at the British Antarctic Survey, who was not involved in the work, said the chemical changes in the upper atmosphere predicted by the study are consistent with what was measured at the Halley Research Station in Antarctica during strong but significant events. Short-lived active particles are emitted from the sun.
But could the environmental impacts be as severe as the team anticipated? “Maybe not that extreme,” Horn said, “but it gives you pause to think,” indicating that it’s unlikely the Earth’s magnetic field will completely disappear.
However, Dr Anders Svenson of the University of Copenhagen said that the ice core from Greenland and Antarctica does not show any evidence of any dramatic climate change that occurred around the time of the Champs voyage, but that did not rule out that it had an effect. “Changes in the ozone layer and the effect of increased UV rays on humans is not something that we can confirm or reject from the ice core,” he said.
The work is important, said Chris Stringer, who studies human origins at the Natural History Museum in London. He argued that the greater use of caves as shelter was reasonable, but the link to elevation in cave art was less convincing because pig paintings were apparently produced in Sulawesi, Indonesia long before Lachamps’ voyage.
“The authors also linked the physical extinction of Neanderthals some 40,000 years ago, and I think it could certainly have contributed to their demise,” he said. “But they have lived longer and have ranged on a much larger scale than just Europe, and we have a very weak fix on the timing of their eventual disappearance across swaths of Asia.”
Dr Richard Stave, a research fellow in quadruple temporal geology at the University of Glasgow, said the study was exciting, and suggested it could lead to further investigation of the environmental and evolutionary effects of other, larger, dramatic declines in Earth’s magnetic field. right on time.