Yellowstone National Park is one of the most beautiful places in America, and quite possibly the world. But it also harbors a secret menace that will kill us all! That is, if you pay attention to clickbait. The danger is real, but it’s much more complicated than it sounds.
Let’s start with the facts. Supervolcanoes are a real scientific term, although technically speaking we’re talking about the Yellowstone Caldera. Think of it like a bottle of soda that you start shaking. As you shake and shake, the pressure builds behind the cap as it fills up. Eventually, the pressure will be enough that even a light twist of the cap will send it rocketing away. Supervolcanoes are kind of like that, except instead of drenching you with sugar water, they cover the surrounding 240 cubic miles with burning ash, magma, and debris. That’s what happens at the top end (8) of the Volcanic Explosivity Index, or VEI.
So, yes, this is bad. Most of Montana, Idaho, and Wyoming would be a fiery hellscape. No fewer than eight cities, including Salt Lake, would need to be evacuated. And we’d have to move quickly, we’d only have, as National Geographic put it, “mere decades.” Wait, what?
Yeah, that’s the thing. Our timelines here are squishy. Supervolcanoes take a long, long time to blow, about 600,000 years, and most of the panic now is because, well, it’s been roughly 600,000 years. In fact, the last VEI 8 eruption happened 26,000 years ago in New Zealand. These things take time. Furthermore, while our ability to detect volcanic eruptions far in the future isn’t great, our short-term systems are pretty good. Granted, getting millions of Americans out of the blast zone would not be a simple process, but there would at least be enough warning.
A larger issue is we don’t really have a good strategy for derailing volcanic eruptions. If you can relieve the pressure, problem solved. Of course, that needs a drill able to handle 1300 to 2400 degrees Fahrenheit, and then you have the problem of where to put all this magma coming out of the big hole you just drilled. Other plans call for removing the heat instead. But that’s some tricky engineering, even in ideal conditions.
The main question mark is what the wider effects would be of the blast. The closest historical equivalent we have is the 1815 eruption of Mount Tambora, which was a VEI 7 blast. That led to enormous, albeit temporary, climate change and the Year Without A Summer, where food prices skyrocketed. Scientists are still arguing over how, exactly, Tambora affected the climate on its own, or whether it was a set of climate problems it just made worse. Nobody’s terribly eager to use the entire planet to test out these theories.
There was also a range of unexpected cultural effects to Tambora. For example, since there weren’t enough oats to feed horses for transportation, the eruption is credited with speeding up the invention of the bicycle. The matter in the atmosphere created gorgeous vistas refracting the light of the sun as it set, preserved in the spectacular sunset paintings of J.M.W. Turner.
So, is it something to be concerned about? Absolutely. But Yellowstone could erupt in a week, twenty years from now, 20,000 years from now, or never again. It’s worth being aware of the risks, and having a plan if a warning goes out, but much like a meteor hitting Earth, you might as well file this under “Deal with it when it happens.” Either that, or start working on one really big drill.