Supervolcanoes scored more news coverage than Sharknado 3 earlier this year when a study published in Nature Communications indicated that humans would have a decent shot at outrunning a supervolcano eruption. Through analyzing ancient and contemporary lava flows of known gigantic events, the authors* identified that flows from these bad boys travel at a leisurely 10 to 45 miles per hour pace. If the toxic gases or ash don’t suffocate you first, outrunning the flow is totally doable in theory, at least by car.

So if theoretically we’re faster than a supervolcano, what could possibly go wrong?

Earning supervolcano classification is all about the size of the eruption and doesn’t necessarily correspond with the size of the volcanic mountain we see above ground. The primary qualifier is that the volume of ejecta (ash, lava, pumice, chicken bones previously lodged in the throat, etc.) must be more than 1,000 cubic kilometers (240 cubic miles). Doing the math: an approximate 15.5-mile by 15.5-mile square area isn’t really more than a geographic blip, until you envision that entire area buried one-mile deep with ash and lava. That’s when it gets real.

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For perspective, the May 18, 1980, eruption of Mount St. Helens spewed approximately 1.0 cubic kilometer of deposits. Most of this fell within a five-mile radius, though measurable accumulations of ash were reported as far away as North Dakota. The volume of a supervolcano eruption would be 1,000 times bigger and would presumably travel much farther.

The aptly named assessment, Volcanic Explosivity Index (VEI), is one of several tools used to qualify volcanic activity. A VEI rating of 8 indicates the magic number of 1,000 cubic kilometers of ejecta was expelled, and a regular eruption earns its cape and superpowers to become a supervolcano. Since it’s a logarithmic scale, an REI 8-rating indicates a tenfold increase of ejecta over a score of 7, one hundredfold over 6, and so on. Mount St. Helens had a VEI rating of 5.

Most of the famous eruptions in recent history aren’t anywhere near supervolcano status, despite their storied levels of destruction. Even though over 36,000 people (some estimates are as high as 100,000) were killed, and reports of global darkening and fiery, smog sunsets were reported the world over for several years, the 1833 eruption of Krakatoa, Indonesia, only earned a VEI rating of 6. Under 10 cubic kilometers of ejecta were expelled. The 1815 eruption of Mount Tambora, Indonesia, is blamed for acute climate change, massive darkening of the skies, harvest failures, and incidences of extreme weather. It rated a 7.

To really drive the point home: a supervolcano would be 10 times more powerful than Tambora and 100 times more explosive than Krakatoa.

Well over 60 supervolcanoes have been identified with a VEI of 8 or above. Some of the most infamous include Yellowstone Huckleberry Ridge (2.1 million years ago/2,450 cubic km); Lake Taupo, New Zealand (340,000 years ago/2,000 cubic km); and Toba, Indonesia (74,000 years ago/2800 cubic km), which holds the honor of being the biggest eruption in the past 25 million years.

Do those really old dates mean we’re in the clear or are we due for the mother of all supervolcanoes?

No one really knows. Most geologists agree that while volcanic and seismic activity can be measured, it can’t be predicted with any certainty. The National Park Service, for instance, says a supervolcano eruption in Yellowstone “is very unlikely in the next thousand or even 10,000 years.” For opposing view, the European Science Foundation is looking into the 70-80 year range. Pick your side.

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Here’s what we know. The odds of winning the lottery average 1 in 13 million. According the USGS, the mathematical probability of a supervolcano eruption in Yellowstone is 1 in 730,000. The agency surrounds those odds with disclaimers as to why you shouldn’t take the numbers too seriously. Unless you’re within range…