Life on Earth, could be much closer to being wiped out than was previously thought, scientists have warned.
Researchers say that most estimates of a cataclysmic volcanic 'super-eruption' - big enough to end civilisation across the planet have been wildly wrong.
After studying geological records dated within the past 100,000 years, scientists at Bristol University discovered that the gap between them was much smaller.
They believe that some sort of the catastrophic event caused by volcanoes or 'bolides' - such as asteroids - will occur once every 17,000 years on average.
It had been believed that such a planet reducing happening came around once every 45,000 to 714,000 years - way beyond our own civilisation's existence.
The last major destructive event, according to their findings, was a super-eruption take took place during the Agricultural Revolution - just 12,000 years ago.
Professor Jonathan Rougier, of Bristol's Schools of Earth Sciences and Mathematics, said: "The previous estimate, made in 2004, was that super-eruptions occurred on average every 45 to 714 thousand years, comfortably longer than our civilisation.
"But in our paper just published, we re-estimate this range as 5.2 to 48 thousand years, with a best guess value of 17 thousand years."
According to geological records, the two most recent super-eruptions were between 20,000 and 30,000 years ago, according to the Mirror .
Prof Rougier added: "On balance, we have been slightly lucky not to experience any super-eruptions since then.
"But it is important to appreciate that the absence of super-eruptions in the last 20 thousand years does not imply that one is overdue. Nature is not that regular.
"What we can say is that volcanoes are more threatening to our civilisation than previously thought."
He said our civilisation will change in unimaginable ways over the next thousand years, and there are many other ways in which it might suffer a catastrophic blow well before the next super-eruption.
On that basis, Prof Rougier says there is little need to plan now for a super-eruption, especially with many other pressing issues to address, which will affect the current and the next generation of humans.
But large eruptions, which are much more frequent, can still be devastating for communities and even countries, and careful planning is a crucial part of disaster risk reduction.
Regarding the findings, published in the journal Earth and Planetary Science Letters, Prof Rougier added: "As well as improving our understanding of global volcanism, our paper develops relatively simple techniques to analyse incomplete and error-prone geological and historical records of rare events.
"These difficulties are ubiquitous in geohazards, and we expect our approach will be used for reappraising other types of hazard, such as earthquakes."