A recent study published in The Royal Society’s Philosophical Transactions A: Mathematical Physical and Engineering Sciences examines how tree-rings in the French Alps have helped researchers determine that Earth experienced a huge jump in radiocarbon levels from a massive solar storm approximately 14,300 years ago. This study was conducted by a collaborative team of researchers from France and the United Kingdom and holds the potential to help scientists and the public better understand how such large solar storms could impact Earth in the future.
“Radiocarbon is constantly being produced in the upper atmosphere through a chain of reactions initiated by cosmic rays,” said Dr. Edouard Bard, who is a Professor of Climate and Ocean Evolution at the Collège de France and CEREGE, and lead author of the study. “Recently, scientists have found that extreme solar events including solar flares and coronal mass ejections can also create short-term bursts of energetic particles which are preserved as huge spikes in radiocarbon production occurring over the course of just a single year.”
For the study, the researchers measured levels of radiocarbon, also known as Carbon-14, within subfossil Scots Pines tree trunks along the eroded banks of the Drouzet River in the Southern French Alps. The tree trunks are considered subfossils since their fossilization process is still ongoing. After discovering the radiocarbon levels date back to 14,300 years ago, they compared this to Greenland ice cores, specifically the chemical element beryllium, which helped determine the radiocarbon levels were caused by a massive solar storm.
Image of tree rings within a buried subfossil tree in the Drouzet River. (Credit: Cécile Miramont)
Image of subfossil trees within the Drouzet River. (Credit: Cécile Miramont)
Image of subfossil trees along the banks of the Drouzet River. (Credit: Cécile Miramont)
The largest, directly observed solar storm occurred in 1859 and became known as the Carrington Event, which not only destroyed telegraph machines but created auroras so bright that birds began to sing because they through the Sun was rising. However, the researchers estimate the solar storm that occurred 14,300 years ago was ten times as strong.
Past studies have identified nine major solar storms that have occurred within the last 15,000 years and have dubbed them as Miyake Events. While the most recent Miyake Events are estimated to have occurred in 774 AD and 993 AD, the team estimates the solar storm that occurred 14,300 years ago is approximately double the size of both of these storms. The team emphasizes that understanding past occurrences of such large solar storms is vital in helping us prepare for the calamity they could cause to Earth, not just in terms of impacting our technology but also the physical calamities they could extoll on humans and other life, as well.
“Extreme solar storms could have huge impacts on Earth,” said Dr. Tim Heaton, who is a Professor of Applied Statistics in the School of Mathematics at the University of Leeds and a co-author on the study. “Such super storms could permanently damage the transformers in our electricity grids, resulting in huge and widespread blackouts lasting months. They could also result in permanent damage to the satellites that we all rely on for navigation and telecommunication, leaving them unusable. They would also create severe radiation risks to astronauts.”
What new discoveries will researchers make about past solar storms and how will such storms impact the Earth in the coming years and decades? Only time will tell, and this is why we science!
As always, keep doing science & keep looking up!
Sources: The Royal Society’s Philosophical Transactions A: Mathematical Physical and Engineering Sciences, EurekAlert!, Wikipedia, National Oceanic and Atmospheric Administration, Wikipedia (1)
Featured Image: Artist illustration of a solar storm interacting with the Earth’s magnetic field. (Credit: NASA)
