Yellowstone volcano threatens to unleash four devastating cataclysms, each more dangerous than the previous event. Each of these “hazardous events” could cause widespread chaos across Yellowstone National Park or even the world at large. Hydrothermal blasts of scorching jets of water are the most likely eruptive event at Yellowstone but are also the least dangerous. Caldera-forming eruptions, however, are the most destructive threat bubbling away underneath the supervolcano complex.
Yellowstone volcano last witnessed such destructive eruptions at three times in its volatile history.
These super-eruptions went off roughly 640,000, 1.3 million and 2.1 million years ago.
The most recent eruption, the Lava Creek eruption, formed Yellowstone’s current 34 miles by 45 miles (55km by 72km) caldera.
Because of the apocalyptic nature of each of these events and the possibility of a fourth blast occurring, scientists at the US Geological Survey (USGS) keep a watchful eye one the supervolcano.
Yellowstone volcano: The USGS revealed the odds of a super-eruption in our lifetime (Image: USGS/GETTY)
Yellowstone is monitored by the Yellowstone Volcano Observatory (YVO) branch of the USGS, which has calculated the odds of another caldera-forming eruption.
According to volcanologist Wendy Stovall, the deputy chief scientist at the YVO, the odds are incredibly low at around “one-in-a-million” but a super-eruption will go off at some point in the future.
The Yellowstone expert said: “Of all the possible volcano hazard scenarios for Yellowstone, by far the least likely includes another major explosive caldera-forming eruption.
“This is certainly the worst-case scenario for Yellowstone, but the chances of it happening in our lifetime are, literally, one-in-a-million.
“At some point in the future, a super-eruption might occur somewhere else on Earth.
“But we may be waiting tens of thousands of years before another such event, worldwide, and it's possible that a super-eruption may never happen again at Yellowstone. We'll leave it at that.”
The most likely event to go off at Yellowstone is a hydrothermal blast of the park’s scorching plumbing system.
Hydrothermal eruptions tend to strike without much prior warning but are typically safe to observe from a distance.
Dr Stovall said: “Smaller explosions occur more often and can impact an area tens of feet in diameter, whereas less-frequent, larger eruption could send hot water and rocks a few thousand feet.”
This is certainly the worst-case scenario for Yellowstone
Wendy Stovall, Yellowstone Volcano Observatory
On average, a hydrothermal explosion goes off at Yellowstone every two years.
These eruptions are usually contained and the risk of harm “is reduced”.
But what about bigger eruptions and earthquakes?
Major earthquakes are the second most hazardous danger at Yellowstone and thousands of tremors strike each year.
Yellowstone volcano: Hydrothermal blasts are the most common eruption at Yellowstone (Image: GETTY)
Yellowstone volcano: The last major eruption was 640,000 years ago (Image: GETTY)
The biggest threat to life comes from major magnitude 7 earthquakes, which are said to hit Yellowstone once or twice a century.
However, Dr Stovall noted major earthquakes “do not operate on a schedule”, making them hard to predict.
After that, the USGS and YVO rank lava flows as the next biggest danger.
Dr Stovall said: “If future volcanic activity at Yellowstone led to an eruption, it would probably result in a lava flow or, less-likely, moderate ashfall.”