(CNN)The reversal of Earth's magnetic poles, along with a temporary breakdown of the world's magnetic field about 42,000 years ago, could have triggered a raft of environmental changes, solar storms and the extinction of the Neanderthals, according to a new study.
Reversal of Earth's magnetic poles may have triggered Neanderthal extinction -- and it could happen again
The Earth's magnetic field protects us, acting as a shield against the solar wind (a stream of charged particles and radiation) that flows out from the sun. But the geomagnetic field is not stable in strength and direction, and it has the ability to flip or reverse itself.
Some 42,000 years ago, in an event known as the Laschamp Excursion, the poles did just that for around 800 years, before swapping back -- but scientists were unsure exactly how or if it impacted the world.
Now, a team of researchers from Sydney's University of New South Wales and the South Australian Museum say the flip, along with changing solar winds, could have triggered an array of dramatic climate shifts leading to environmental change and mass extinctions.
Scientists analyzed the rings found in ancient New Zealand kauri trees, some which had been preserved in sediments for more than 40,000 years, to create a timescale of how Earth's atmosphere changed over time.
Using radiocarbon dating, the team studied cross sections of the trees -- whose annual growth rings served as a natural time stamp -- to track the changes in radiocarbon levels during the pole reversal.
"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 s