Did you know that Yellowstone National Park sits on a supervolcano?

I didn’t — until I watched Rachel and Matt’s Coolest Stuff video podcast on the place and they frightened me to death. And then, just as I was about to write about how scary the supervolcano is, it got supersized. A recent study published in the “Journal of Volcanology and Geothermal Research” says that the magma chamber a few miles beneath Yellowstone is 20 percent larger than previously thought, according to ScienceDaily. So if the thing erupted, the devastation would be worse than everyone expected — if that’s possible.

How bad did it look before its size got recalculated? According to the Discovery Channel, an eruption would take out the whole park, the nearby communities, and ash pouring out of the park would spread all the way to the Pacific Coast and throughout the Midwest. It would even cause worldwide weather problems. The last time the supervolcano erupted — 640,000 years ago — it ejected 8,000 times the ash and lava that was ejected from Mount St. Helens when it erupted in 1980. Mount St. Helens ash spread 22,000 square miles. The ash from Yellowstone’s ancient eruptions showered as much as half of today’s United States, according to ScienceDaily.

But how does a volcano get the prefix “super”? According to Discovery, a volcano is super when it erupts infrequently and really puts on a show when it blows. For example, when Yellowstone erupted 2.1 million years ago, it had 10-mile-high towering ash cloud, and poured about 1,000 cubic miles of ash. Good grief.

Let’s hope mellow Yellowstone doesn’t get angry — because you know what happens when someone who never gets angry, gets angry: well, something much more cataclysmic than Old Faithful.

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