Researchers have identified the largest solar storm ever recorded in 14,300-year-old ancient tree rings

An international team of scientists has discovered a spike in radiocarbon levels 14,300 years ago by analyzing ancient tree rings found in the French Alps.

The radiocarbon spike was caused by a massive solar storm, the largest ever identified.

A similar solar storm today would be catastrophic for modern technological society, potentially wiping out communications and satellite systems, causing widespread power outages, and costing us billions of pounds.

Academics warn that understanding such storms is important to protect the global telecommunications and energy infrastructure in the future.

The collaborative research, conducted by an international team of scientists, has been published in Philosophical Transactions of the Royal Society A: Physical and Engineering Mathematical Sciences It reveals new insights into the Sun’s extreme behavior and the dangers it poses to Earth.

A team of researchers from Collège de France, CEREGE, IMBE, the University of Aix-Marseille and the University of Leeds have measured radiocarbon levels in ancient trees preserved within the eroded banks of the Druzet River, near Gap, in the southern French Alps.

Tree logs, which are fossil remains that have not completed the fossilization process, are cut into small single tree rings. Analysis of these individual episodes identified an unprecedented rise in radiocarbon levels, which occurred precisely 14,300 years ago. By comparing this spike in radiocarbon with measurements of beryllium, a chemical element found in Greenland’s ice cores, the team suggests that the spike was caused by a massive solar storm that would have spewed huge amounts of energetic particles into Earth’s atmosphere.

“Radiocarbon is constantly produced in the upper atmosphere through a series of reactions initiated by cosmic rays,” said Edouard Bard, professor of climate and ocean evolution at the Collège de France and CEREGE, and lead author of the study. “More recently, scientists have discovered that extreme solar events with In that solar flares and coronal mass ejections can also create short-lived bursts of energetic particles that are preserved as huge spikes in radiocarbon production that occur over the course of just one year.

Researchers say that similar massive solar storms today could be catastrophic for modern technological society, potentially destroying communications, satellite systems and electricity networks, and costing us billions of pounds. They warn of the importance of understanding the future risks of such events, to enable us to prepare, build resilience into our communications and energy systems and protect them from potential damage.

Tim Heaton, professor of applied statistics in the School of Mathematics at the University of Leeds, said: “Severe solar storms can have massive impacts on Earth. Such superstorms could permanently damage transformers in our electricity networks, leading to widespread blackouts. “Wide and huge.” “It could also lead to permanent damage to the satellites we all depend on for navigation and communications, rendering them unusable. It would also create severe radiation risks for astronauts.”

Nine of these intense solar storms – known as Miyake events – have now been identified as having occurred over the past 15,000 years. The most recent confirmed Miyake events occurred in 993 AD and 774 AD. However, this newly identified 14,300-year-old storm is the largest ever discovered, being nearly twice the size of those two storms.

The exact nature of the Miyake events is still not well understood, as they have never before been effectively observed directly. They highlight that we still have a lot to learn about the Sun’s behavior and the risks it poses to society on Earth. We don’t know what causes such intense solar storms, how frequently they occur, or whether we can somehow predict them.

Professor Bard said: “Direct automated measurements of solar activity only began in the 17th century with sunspot counting. Nowadays, we also obtain detailed records using ground-based observatories, space probes and satellites. However, all these short-range instruments have insufficient records. To fully understand the sun. “Radiocarbon measured in tree rings, used together with beryllium in polar ice cores, provides the best way to understand the Sun’s past behavior.”

The largest directly observed solar storm occurred in 1859 and is known as the Carrington event. It caused massive disruption to the Earth, destroying telegraph machines and creating a nighttime twilight so bright that birds began to sing, thinking the sun was beginning to rise. However, the Miyake events (including the newly discovered 14,300-year-old storm) would have been an astonishing amount of magnitude larger.

Professor Heaton said: “Radiocarbon dating provides a fascinating way to study the Earth’s history and reconstruct its crucial events. An accurate understanding of our past is essential if we are to accurately predict our future and mitigate potential risks. We still have a lot to learn.” “Each new discovery not only helps answer existing key questions, but can also generate new questions.”

“Finding such a collection of preserved trees was truly exceptional,” said Cécile Miramont, Associate Professor of Paleoenvironments and Paleoclimates at IMBE, University of Aix-en-Provence. “By comparing the width of individual tree rings in multiple tree trunks, we were then able to find out.” We carefully assembled separate trees to create a longer timeline using a method called dendrochronology. “This allowed us to discover invaluable information about past environmental changes and measure radiocarbon over an unknown period of solar activity.”