The Yellowstone Supervolcano Is Putting on the Best Show in America Right Now
The single largest active geyser in the world is Yellowstone National Park’s Steamboat Geyser. Double vents shoot boiling water more than 300 feet into the sky, sometimes showering the parking lot a quarter mile away. Recorded eruptions have lasted more than an hour. They have toppled fully grown trees, and then washed them away. For days after, steam blows out from the geyser so loudly you have to yell to be heard, and it soaks you as if you were standing in the rain. The volume of water and debris expelled is 10 times that of Old Faithful.
Between 1911 and 1961, Steamboat didn’t erupt at all. Then, between 1962 and 1966, it erupted at least 84 times. For the most part, it has since been recorded erupting on the order of once or twice per year, and just 10 times this century -- until March 15 of this year. In the six months since, it’s erupted 24 times.
The most iconic feature of Yellowstone is Old Faithful, the park’s largest geyser to erupt on a regular schedule (give or take a few minutes). But Old Faithful is not representative of how most of the park’s geysers actually work. Yellowstone contains around 500 geysers -- half of all the geysers in the world -- and most are entirely unpredictable, including Steamboat; its next eruption might be in half a century, or it might be tomorrow. Scientists conducting field work in April missed one by 15 minutes. You can’t stake them out, which is why Steamboat eruptions are such emotional events for anybody who happens to witness them.
Steamboat blew the day before I met with Yellowstone National Park Geologist Jeff Hungerford in August, and he visibly perked up in his chair as soon as I mentioned it. People all over the park were talking about it, with the sort of rapidly inflating excitement you’d associate with lottery numbers or hot streaks in baseball games. We have no idea why Steamboat is currently behaving this way. But the ground underneath it is currently rising, and, from what we know about such bursts of increased activity, if ever there was a time to visit in the hopes that you could be lucky enough to see it, that time would be right now.
Most people don’t know all this, the stuff that makes Steamboat so fascinating. They don’t necessarily know it’s there to look for. What they do know, thanks to a supremely irritating chorus of internet Doomsday preppers and tabloids, is the supervolcano.
The Yellowstone Caldera – which the public prefers to call a supervolcano -- is the largest volcanic system in North America. It’s one of the largest active volcanoes in the world. Around 2.1 million years ago, it erupted so spectacularly that falling ash reached almost to present-day Missouri. A second eruption – not high enough on the Volcanic Explosivity Index to be classified as a supereruption, though it’s frequently reported that way – followed 1.3 million years ago. The most recent supereruption, around 640,000 years ago, collapsed the center of what’s now Yellowstone National Park into the Rhode Island-sized caldera we have today.
The Yellowstone supervolcano has been a popular viral conspiracy theory fodder for years. Content farms like the Express shriek about the forthcoming supervolcano DEATH ZONE while self-titled volcano-forecasters claim they’re tracking the next supereruption (soon, maybe!) life-saving work for which they accept PayPal (yours!). There is really just one scam in the world, which is to create a fear, position yourself as the only one who can be trusted to alleviate that fear, and then monetize.
Michael Poland, Scientist-in-Charge at the Yellowstone Volcano Observatory, has been getting calls and emails for months about how Steamboat erupting must be a sign the supereruption is neigh. “The biggest misconception [is] that there’s going to be one gigantic eruption and it’s going to happen any minute,” Poland says. “And that’s propagated by a lot of people online that are misrepresenting data. And what I find particularly disgusting is that a lot of these people are asking for donations and making money off of, basically, making people scared.”
Most of the fear-mongering hinges on the assumption that Yellowstone’s only kind of eruption is a supereruption. This is untrue. Yellowstone is phenomenally, singularly diverse in its geological activity, and is far less prone to explosive eruptions than to, say, lava flows, which slowly ooze the lava out from the volcano like toothpaste and are pretty benign on the scale of things. The last lava flow out of Yellowstone was 70,000 years ago, and if anything, the next eruption event would much more likely be one of those. But toothpaste does not inspire donations the way DEATH ZONEs do.
Nor is it at all true that the Yellowstone volcano is ‘overdue’ to erupt. For starters, this is simply not how volcanoes work. And more specifically, the hot spot driving all this looks to be heading away from the Yellowstone Plateau altogether; as the North American tectonic plate moves to the Southwest, the hot spot has accordingly been shifting up and to the East. “There’s a lot of deformation going on, but all indicators that we see -- seismic, gas, heat, deformation -- are well within the norm for this system,” Hungerford says, referring to the ground falling or rising like we’re seeing right now with Steamboat. “It’s quite possible we won’t have, from Yellowstone volcano, a supereruption ever again.”
It’s worth noting that by all accounts – even without knowing the hot spot’s moving away -- no one actually living and working the DEATH ZONE themselves gives any sort of a shit about it.
“Oh, visitors ask all the time. It has some people freaking out,” says backcountry office volunteer Bob Youtz. “Nobody here thinks about it. At all.” There’s some small irony in the fact that Yellowstone has no (free) WIFI and next to no cellular service – it’s when you’re physically inside the park that you’re safest from the DEATH ZONE since the place the DEATH ZONE actually solely exists is online.
“I’ve been here 28 years, never thought about it,” a bartender at the Old Faithful Inn says when I mention the fixation. “When it goes, I’ll be gone.”
A few scientific branches have been made sexy by a steady supply of novel, tangible applications like drug development or automation. Geology is not one of them. Yet so extraordinary is Yellowstone’s confluence of features that anyone paying attention doesn’t need to come up with gimmicks to reinvent it; it does that on its own.
The park’s 10,000-plus hydrothermal features -- the largest concentration anywhere in the world -- ranging from geysers to travertine terraces to fumaroles to mud pots to hot springs. Old Faithful’s regularity allows you to take it for granted by definition, but it’s really the chaos of Steamboat and Yellowstone’s other thermal features that more effectively reminds visitors they’re walking on top of an active volcano. In September, an eruption from Ear Spring Geyser showered the park with decades’ worth of objects ranging from cement blocks to pencils to pacifiers (don’t litter, guys). Curators are currently working through the inventory.
Yellowstone sits on the Continental Divide, the highest point in the Rocky Mountains, and so has a constant and outsized supply of water from rain and snow. The magma chambers underneath Yellowstone provide an outsized source of heat -- enough magma to fill the Grand Canyon more than 15 times. And crucially, Yellowstone sees several thousand earthquakes each year. Only two or three of these might be felt by humans, but they’re what allow water to percolate down under the geysers, get heated by the magma and then when enough pressure builds, rush back up. The regular earthquakes fracture the internal plumbing, shaking the pipes open and thus keeping the hydrothermal system alive; without them, geysers like Old Faithful would seal themselves shut for good.
“Yellowstone, one of the things that makes it special is it’s a very dynamic place, it’s constantly changing on timescales that humans can appreciate,” Hungerford says. “That’s not an indication that anything bad is going on, and I think that’s a mistake a lot of people make, [thinking] that any change is bad. Yellowstone is defined by change. That’s the way the system works.”
Yellowstone is weighted toward chaos, toward unpredictability. Even Old Faithful isn’t going to be faithful forever – the interval between eruptions has been increasing over the last 50 or so years.
The reason science isn’t better equipped than junk science for the battle of public perception -- despite being armed with the actual facts -- is that most science, for most of the public, still requires a certain degree of faith. We know Mount Rainier will erupt again one day, but for each of however many days until it does it will look exactly the same, and that’s how it is with just about everything. But in Yellowstone, “you can wake up and the ground has switched from going up to going down,” Poland says, “or going down to going up,” and this is what makes science here wondrous even to people who normally find science boring: you can see it.
“Geology, in general, we tend to think of as very static,” Poland says. “Things don’t change, except very slowly over time. The Grand Canyon gets cut over millions and millions of years; it takes time for rivers to erode things; even volcanoes, you might say, ‘oh, this particular volcano is never going to erupt in my lifetime.’ But Yellowstone is one of those places on Earth where things can and do change. It doesn’t necessarily have to be catastrophic change like one of these huge eruptions. Geysers go off and new geysers form and old geysers go dormant, springs change their activity... that’s one of the reasons I think it’s so compelling, not only to scientists but also to the public.”
We’re never going to see Yellowstone supererupt. But we will see it change before our eyes, and we’ll see its capacity to surprise us, to put on a better show than whatever fan-fiction anyone could ever come up with online. When you visit Yellowstone, you’re reminded the Caldera isn’t merely an abstract used to weaponize fear, but an actual geological feature about 30 by 45 miles across. You can walk around it (or drive) from just past Canyon Village (where there’s an exhibition on it in the visitor’s center) down through the upper half of Yellowstone Lake, to nearly the western edge of the park up past Old Faithful and almost up to Norris, the park’s hottest and most dynamic geyser basin, the one that contains Steamboat.
Yellowstone is extraordinary in that it doesn’t just function to preserve old things; it creates new ones. It’s our nation’s best ambassador to people who see no reason to trust science, so long as they aren’t so far gone they’ve lost the human instinct toward curiosity. And it’s a lighthouse for those of us who woke one day to find that the ground had switched from up to down, that all the things we thought of as qualitatively good – science, education, climate health, truth – were things people had decided were bad. It lets us watch the planet’s most fascinating extremes playing out in real time. It shows us something good to believe.