An apocalyptic volcanic super-eruption could be closer than previously thought, according to a new analysis.
Regular volcanic eruptions, such as the recent activity of Mount Agung in Bali, might be enough to close airports, but a super-eruption would have the potential to destroy human civilisation as we know it.
Like Mount Agung, one of the last known super-eruptions also took place in Indonesia – 74,000 years ago.
It involved up to 3,000 cubic kilometres of rock and ash being blasted into the air at the site of what is now Lake Toba on the island of Sumatra.
The largest super-eruptions are capable of covering entire continents in volcanic ash, and changing weather patterns around the world for decades.
Now, a new study suggests the next eruption of this size could be sooner than we think.
Scientists previously estimated that super-eruptions happen every 45,000-714,000 years, a length of time Professor Jonathan Rougier, statistician and lead author of the new study, describes as “comfortably longer than our civilization”.
Civilisation is often dated to the time humans moved away from hunting and gathering and towards agriculture, around 12,000 years ago.
In the new Earth and Planetary Science Letters study by Professor Rougier and his team at the University of Bristol, they used a database of geological records to produce a new estimate of between 5,200 and 48,000 years, with a “best-guess value” of 17,000 years.
Records suggest that the two most recent super-eruptions took place between 20,000-30,000 years ago.
“On balance, we have been slightly lucky not to experience any super-eruptions since then,” said Professor Rougier.
Dr Marc Reichow, a geochemist at the University of Leicester who was not involved in the study, says these new findings are based on “sound statistical analysis”.
“The approach and assessment are robust, and certainly will help us understand and most importantly may help predict future eruptions,” said Dr Reichow.
“However nature, including volcanic eruptions, does not necessarily work as clocks work.”
Professor Rougier agrees that the lack of super-eruptions in the last 20,000 years does not necessarily mean one is just around the corner.
“Nature is not that regular,” he said.
There are more important environmental challenges to tackle in the meantime, not least the eruption of smaller volcanos such as Mount Agung. Though they are not as dramatic, such eruptions still have the potential to devastate communities and nations.
“What we can say is that volcanoes are more threatening to our civilization than previously thought,” said Professor Rougier.
