When Do the Magnetic Poles Flip Again

(CNN)The reversal of Earth's magnetic poles, along with a temporary breakdown of the world's magnetic field well-nigh 42,000 years agone, could have triggered a raft of environmental changes, solar storms and the extinction of the Neanderthals, co-ordinate to a new study.

The Earth'south magnetic field protects us, acting equally a shield confronting the solar wind (a stream of charged particles and radiation) that flows out from the lord's day. Just the geomagnetic field is non stable in strength and direction, and it has the ability to flip or opposite itself.

Some 42,000 years ago, in an event known as the Laschamp Excursion, the poles did simply that for around 800 years, earlier swapping back -- but scientists were unsure exactly how or if it impacted the world.

Now, a squad of researchers from Sydney's Academy of New Due south Wales and the South Australian Museum say the flip, along with changing solar winds, could accept triggered an array of dramatic climate shifts leading to environmental alter and mass extinctions.

Scientists analyzed the rings found in ancient New Zealand kauri trees, some which had been preserved in sediments for more than than twoscore,000 years, to create a timescale of how Earth's temper inverse over fourth dimension.

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 copse nosotros could measure, and date, the spike in atmospheric radiocarbon levels caused past the plummet of Earth's magnetic field," Chris Turney, a professor at UNSW Science, director of the academy's Globe and Sustainability Scientific discipline Research Middle and co-pb author of the study, said in a statement.

The team compared their new timescale with site records from caves, water ice cores and peat bogs around the world.

'End of days'

Researchers found that the reversal led to "pronounced climate change." Their modeling showed that ice sail and glacier growth in North America and shifts in major wind belts and tropical tempest systems could be traced dorsum to the flow of the magnetic pole switch, which scientists named the "Adams Event."

"Finer, the Globe's magnetic field almost disappeared, and it opened the planet upwards to all these high free energy particles from outer space. Information technology would've been an incredibly scary time, almost similar the cease of days," Turney said.

Researchers say the Adams Event could explicate many of Earth's evolutionary mysteries, including the extinction of Neanderthals and the sudden widespread appearance of figurative fine art in caves worldwide.

The phenomenon would have led to some dramatic and dazzling events. In the lead-upwardly to the Adams Result, the Earth's magnetic field dropped to only 0% to half dozen% of its strength, while the Sun experienced several long lasting periods of quiet solar activity.

"We essentially had no magnetic field at all -- our cosmic radiation shield was totally gone," Turney said.

The weakening of the magnetic field meant that more space weather, such as solar flares and galactic cosmic rays, could head to World.

"Unfiltered radiation from space ripped autonomously air particles in Earth'due south atmosphere, separating electrons and emitting light -- a process called ionisation," said Turney in a statement. "The ionised air 'fried' the Ozone layer, triggering a ripple of climate change beyond the globe."

During this time, World's inhabitants would accept been subjected to some dazzling displays -- northern and southern lights, acquired by solar winds hitting the Globe's atmosphere, would take been frequent. Meanwhile, the ionized air would've increased the frequency of electrical storms -- something that scientists think caused humans to seek shelter in caves.

"The mutual cave fine art motif of red ochre handprints may bespeak it was existence used as sunscreen, a technique still used today by some groups," Alan Cooper, honorary researcher at the Due south Australian Museum, said in a statement.

"The amazing images created in the caves during this time take been preserved, while other art out in open areas has since eroded, making it appear that art of a sudden starts 42,000 years agone," Cooper, co-atomic number 82 author, added.

An upcoming reversal

In the paper, published in the journal Science, experts say in that location is currently rapid movement of the north magnetic pole beyond the Northern Hemisphere -- which could point another reversal is on the cards.

"This speed -- alongside the weakening of Earth'south magnetic field past around 9 per cent in the past 170 years -- could indicate an upcoming reversal," said Cooper.

"If a similar outcome happened today, the consequences would be huge for modern lodge. Incoming catholic radiations would destroy our electric power grids and satellite networks," he said.

Human action has already pushed carbon in the temper to levels "never seen past humanity earlier," Cooper said.

"A magnetic pole reversal or farthermost change in Sun activity would be unprecedented climate change accelerants. Nosotros urgently need to get carbon emissions down before such a random event happens again," he added.

goreprucapterse.blogspot.com

Source: https://www.cnn.com/2021/02/19/world/magnetic-fields-earth-intl-scli-scn/index.html

Share this post