“Using the ancient trees we could measure, and date, the spike in atmospheric radiocarbon levels caused by the collapse of Earth’s magnetic field,” Chris Turney, a professor at UNSW Science, director of the university’s Earth and Sustainability Science Research Center and co-lead author of the study, said in a statement. The team compared their new timescale with site records from caves, ice cores and peat bogs around the world. Researchers found that the reversal led to “pronounced climate change.” Their modeling showed that ice sheet and glacier growth in North America and shifts in major wind belts and tropical storm systems could be traced back to the period of the magnetic pole switch, which scientists named the “Adams Event.”
“Effectively, the Earth’s magnetic field almost disappeared, and it opened the planet up to all these high energy particles from outer space. It would’ve been an incredibly scary time, almost like the end of days,” Turney said. Researchers say the Adams Event could explain many of Earth’s evolutionary mysteries, including the extinction of Neanderthals and the sudden widespread appearance of figurative art in caves worldwide… [T]he ionized air would’ve increased the frequency of electrical storms — something that scientists think caused humans to seek shelter in caves…
In the paper, published in the journal Science, experts say there is currently rapid movement of the north magnetic pole across the Northern Hemisphere — which could signal another reversal is on the cards. “This speed — alongside the weakening of Earth’s magnetic field by around nine per cent in the past 170 years — could indicate an upcoming reversal,” said Alan Cooper, honorary researcher at the South Australian Museum. “If a similar event happened today, the consequences would be huge for modern society. Incoming cosmic radiation would destroy our electric power grids and satellite networks,” he said.
Human activity has already pushed carbon in the atmosphere to levels “never seen by humanity before,” Cooper said. “A magnetic pole reversal or extreme change in Sun activity would be unprecedented climate change accelerants. We urgently need to get carbon emissions down before such a random event happens again,” he added.
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