The eruptions of so-called supervolcanoes – those that, strictly speaking, produce eruptions that eject at least 1,000 cubic kilometers (240 cubic miles) of material – may rattle the bones. However, they’re not as apocalyptic as they look. If Yellowstone’s supervolcano erupted today, for example, it’d be devastating, but humanity would certainly pull through.
A new Nature study doubles down on this perhaps counterintuitive fact. Looking at the Toba supervolcanic eruption around 74,000 years ago, a team led by Arizona State University (ASU) have concluded that one group of humans was barely left with a scratch despite the cataclysm that took place.
This supereruption, coming in as the most explosive in the last 2 million years, certainly had murderous potential. The blast on Sumatra excavated a crater 100 kilometers (62 miles) across, and generated up to 2,800 cubic kilometers (672 cubic miles) of volcanic debris that was scattered across the planet.
The global effects of this supereruption are heavily debated. It wasn’t long ago that it was thought that the masses of sunlight-reflecting sulfuric acid clumps up on high triggered a volcanic winter so potent and prolonged that it killed off a cornucopia of life. Most dramatically, humanity itself was suspected of being pushed to the brink of extinction.
As such climatic effects are always the most dangerous aspects of significant eruptions, teams across the world have been searching for signs of it in locations across the world. Primarily because the volcanic winter effect can’t be found in plenty of geological deposits, such human extinction ideas have largely fallen out of favor.
This new study took a slightly different approach to such precursors.
“The only way to determine if populations survived Toba is to find the shards directly interstratified with evidence of human behavior,” senior author Professor Curtis Marean, associate director of the Institute of Human Origins at ASU, told IFLScience.
“Our study is the only one to have done that anywhere in the world.”