Science Vs - Supervolcanoes: Is Yellowstone Gonna Blow?

Episode Date: October 22, 2020

We keep hearing that a Yellowstone supervolcano could blow at any moment — and possibly wipe us all out. So is Yellowstone overdue for the BIG ONE, and if it happens, how bad could it be? To find out, we talk to paleoecologist Dr. Gill Plunkett, Yellowstone Volcano Observatory Scientist-in-Charge Dr. Mike Poland and Washington resident Christian Jacobsen.  Here’s a link to our transcript: https://bit.ly/3kliFV6 Check out Yellowstone Volcano Observatory’s weekly blog the “Caldera Chronicles”: https://www.usgs.gov/volcanoes/yellowstone/caldera-chronicles This episode was produced by Michelle Dang and Nicholas DelRose, with help from Wendy Zukerman, Rose Rimler and Hannah Harris Green. We’re edited by Blythe Terrell. Fact checking by Barbra Rodriguez. Mix and sound design by Sam Bair. Music written by Peter Leonard, Marcus Bagala, Emma Munger and Bobby Lord. A huge thanks to all the researchers we got in touch with for this episode, including Brian Wilcox, Dr. Mike Rampino, Dr. Jazmin Scarlett, Dr. Joe McConnell, Dr. Rosaly Lopes and Dr. Thor Thordarson. And special thanks to the Zukerman family and Joseph Lavelle Wilson. Learn more about your ad choices. Visit podcastchoices.com/adchoices

Hi, I'm Wendy Zuckerman, and you're listening to Science Versus from Gimlet. This is the show that pits facts against fiery mountains. Our story begins with Christian Jacobson. It's 1980, and he lives in Redmond, Washington. So, I was 12? I was a rocker kid? One morning, Christian woke up early. He was eating Cheerios and Raisin Bran. He liked to mix them half and half.

Everything was quiet. When suddenly... I heard like a door slam downstairs. And I thought, hang on, I thought I was the only person up. He was. But something else had woken up. Mount St. Helens, a snow-capped mountain just a few hours south of Christian's house. It had been rumbling for months,

a mixture of hot, gooey rock called magma was building and building inside it. And then, on May 18th, 1980, it finally blew its top. Blam! Downstairs. That was the sound of the eruption that I heard. Mount St. Helens shook with its most violent eruption in 123 years. The volcano's blasts have come with a vengeance today. The conically shaped top of the mountain is now gone. The eruption shot ash 15 miles into the sky, and that ash spread all across the state.

When Christian opened his door to step outside, it was like Dorothy stepping over the threshold into technicoloured Oz, only in reverse. I walked out on the deck and I looked at my mom's planters there where she had these poppies growing big pink poppies they were covered in a fine dust and I just touched it really lightly and it just came off on my fingers and it was like as fine as like chalk dust from like a chalkboard and as I looked away from the flowers I saw it was just on everything. Freaking everywhere. In neighboring towns, the ash got so thick that it made the sky turn black.

Day was like night. And for Christian, the ash found its way into his eyes and throat. I felt the grit in my teeth. And from when you breathe it in, it just gets in your mouth. Kind of like if it was a hyperfine sand and like breathing in sand or something. The volcano's blast also created this massive wave of heat that flattened everything for miles. Christian remembers seeing a forest of huge pine trees just on the ground.

All of the trees are laid down and pointing in one direction. They are completely stripped of all the branches and everything. They're just the trunk of the tree laid down like a giant has been playing with pickup sticks. But the thing that really shocked Christian was when he realized that the eruption had created a giant mud flow. That hot rock and gas had melted all the ice at the top of the mountain, causing... Like an eight-lane highway of rocks and trees and superheated mud coming, hurtling down, crashing in and taking out every single bridge that it touched, you know, railroad bridges and freeways and everything. I mean, when you see something like that, that's something that, knowing there's something

that powerful and that much bigger than you is scary. The Mount St. Helens eruption killed 57 people. The Mount St. Helens, it isn't even close to the most deadly volcano out there. Just five years later, a volcano erupted in Colombia, creating a landslide that killed 24,000 people. And in the past, even bigger volcanoes have erupted, so-called super volcanoes. The one we hear about here in the US is Yellowstone. And that's where a lot of people are looking to right now. Because there are rumblings that Yellowstone is about to blow. And if that happens, it would be catastrophic.

Christian has heard these rumours too, that Yellowstone will make Mount St Helens look like a pimple. That's not going to be an eruption like anything we've seen in written history, I don't think. That's just going to open up a hole where everything that's underneath us is going to come out, and it's going to come out in a terrible, terrible way. Everything from the Pacific Ocean to, you know, Minnesota is gone. And on top of all that, there are stories that a Yellowstone blast could change the climate, hurling us into a new ice age.

So today on the show, we're asking, is that even possible? Just how scary can volcanoes get? When it comes to volcanoes, there's a lot of... Blam! But then, there's science. Science vs. Volcanoes is coming up just after the break. It's season three of The Joy of Why, and I still have a lot of questions. Like, what is this thing we call time?

Why does altruism exist? And where is Jana Levin? I'm here, astrophysicist and co-host, ready for anything. That's right. I'm bringing in the A-team. So brace yourselves. Get ready to learn. I'm Jana Levin.

I'm Steve Strogatz. And this is... Quantum Magazine's podcast, The Joy of Why. New episodes drop every other Thursday, starting February 1st. What does the AI revolution mean for jobs, for getting things done? Who are the people creating this technology? And what do they think? I'm Rana El-Khelyoubi, an AI scientist, entrepreneur, investor, and now host of the new podcast,

Pioneers of AI. Think of it as your guide for all things AI, with the most human issues at the center. Join me every Wednesday for Pioneers of AI. And don't forget to subscribe wherever you tune in. Welcome back. We just heard that if a volcano blows up in your neighborhood, it's bad news for you. But one of the scariest things that we hear about huge volcanoes is that they can actually mess with the climate, causing havoc all over the world. So how bad can that be? To find out, we called up a volcano lover. The force, the power that's contained beneath volcanoes is awesome.

This is Jill Plunkett from Queen's University Belfast in Northern Ireland, and she studies awesome volcanoes that have erupted thousands of years ago. And she said that this work can take scientists to perhaps the opposite of where you'd expect, not smoking mountaintops, but to giant fields of ice, drilling deep in places like Greenland. In some cases, they've gone down three kilometres into the ice. Oh my gosh. It is incredible what they can do. And what these scientists are looking for in the ice is the

stuff that fell all over Christian's house, volcanic ash. Not ash like when we burn wood, but volcanic ash is essentially glassy material. And some shards are really beautiful and some are really dull. But whether they're beautiful or dull, it's what they tell us. And to Jill, these bits of volcanic ash can tell her a lot. When large volcanoes blow a load, the winds take that ash around the world. And when it lands in places like Greenland, the ice kind of acts like a perfect time capsule. Because each year, as more and more

snow falls on top of the ash, it basically encases this volcanic ash for thousands of years until scientists come and drill it out, ready to study it. Like, what does it look like? Like dirty ice cubes? No, it's beautifully clean ice. Recently, Jill's colleague found some very, very curious volcanic ash trapped in ice 500 metres down. And because of how deep it was, they estimated that it came from a volcano that erupted more than 2,000 years ago.

To figure out exactly which volcano blew, Jill's team uses that ash, which is sometimes called tephra. And it turns out that tephra from different volcanoes has its own special chemical cocktail with different amounts of stuff like silica, aluminium or magnesium. It's kind of like a fingerprint. And Jill is like a volcano detective. She uses her database of tephra to find the suspect.

And I do that one by one through the elements. And gradually the filter is getting rid of all the tephras that don't match. And I'm left with one. And it was really nice. This one was looking like a perfect match. Turns out it's Okmok. Okmok. It's a volcano on a small island off the southern coast of Alaska. And it's part of the so-called Ring of Fire, which are a string of volcanoes that sit on the boundary of massive tectonic plates. And these plates kind of grind away at each other. So you get the pressure built up by the clashing of the two tectonic plates. So when this Alaskan volcano blew, how bad was it? Well, when Jill's team looked at the ice, they could see that it had certain

kinds of sulfur in it. And that told them this would have been a big eruption. From the amount of sulfur it produced, we can say that it was certainly one of the largest eruptions in the last two and a half thousand years. When it erupted, it erupted explosively. Material being thrown up into the atmosphere, being spat out in different directions. And we know that when big volcanoes throw enough sulphur up into the stratosphere, this can change the climate. Because once these tiny droplets of sulphur are in the air, they kind of act like little mirrors that reflect heat from the sun away from earth, making things cooler. But Jill and her team wanted to know how much colder it would have gotten. The only problem, 2,000 years ago... They didn't have thermometers back then, so they couldn't say

it got so many degrees colder. What we do have are tree ring records. Looking at tree rings is like leafing through nature's diary. You can see when the weather is great for trees because they grow fast and you can see when it gets cold and crappy. And other scientists keep a library of tree rings. So Jill and her team checked to see what were the trees up to when this volcano blew. And it turned out that a lot of them were quite unhappy. We see what was called a frost ring. The trees seem to have suffered from what is presumed to be an early frost. Oh, wow. The summer had gotten cooler and the trees didn't like it.

They saw this in trees from California to Europe. And in fact, scientists have estimated that when this volcano blew, the temperature in summer probably fell by several degrees over in Europe. And all of this, it wouldn't just affect the trees. There's evidence that this colder weather made a big difference for people living in the Roman Republic at the time. Ancient Romans recorded a rough year. They said that their crops failed, and it was bad timing. The Roman Republic was at war. They were facing things like extreme weather, they had food shortages, so they found themselves eating things that had never been tasted before by men. One philosopher wrote that Roman armies were struggling to get proper food

and scraping by on stuff like roots and bark. It's even possible that this volcano made things so bad for the Romans that it helped topple the Roman Republic. Now this kind of sounds wild that an angry volcano could take down a republic that was more than 400 years old. But the thing is, after years of war and the assassination of Julius Caesar, the volcano erupted. And soon after that bitter cold, the republic basically collapsed. It would seem that all this political turmoil was going on for a long period of time. And still they were trying to keep things going. So the volcano erupting could have been the final straw in the Republic? The final straw.

We can certainly see that they weren't having an easy time of it after the eruption. To say it lightly. To say it lightly. To say it lightly. So, why was Okmok so explosive and managed to cause so much havoc? Well, Jill says it's because of the kind of magma that was brewing in its belly. It was full of silica and gas bubbles.

It's more volatile. When it explodes, it's like, you know, you're shaking a fizzy water bottle and opening the lid suddenly. Oh, so it's actually the chemistry of the magma. It like has, you know, volcanic TNT in it. Pretty much. So they can see that we've got this highly volatile type of magma. Other volcanoes have less gassy and explosive magma, like a lot of the ones in Hawaii. Their chemical cocktail is more like flat soda. It's less likely to go kaboom. And so when these volcanoes do erupt,

the lava is more likely to kind of just seep out. Okay, so we've just heard that some volcanoes can blow and change the climate, maybe even bring civilizations to their knees. But what does that mean for Yellowstone? Would it be like Ock Mock on steroids? Waiting, waiting, waiting, and then boom. Sitting under Yellowstone is a direct pipeline from the Earth's core, funneling heat towards the surface. And when this volcano blew two million years ago, it left a hole in the ground larger than Rhode Island.

Scientists estimate that another Yellowstone blowout wouldn't bring in an ice age, but it could bring temperatures down in the Northern Hemisphere for years. And worse still, the news is telling us that this could happen again. At any moment. Yellowstone National Park could be sitting on a time bomb. We end here tonight with a sleeping giant, an ancient super volcano. Recent eruptions have some wondering if the giant is awakening.

So is that true? Is 2020 about to get catastrophically worse? The sleeping giant awakens? After the break. Welcome back. We've talked about how volcanoes can be pretty bloody scary, even if you're living thousands of miles away from them. Our next question is,

how will we know if one of these big cats is about to roar? Like, could Yellowstone really just erupt at any time and leave a giant hole in the United States? For this, we called up Dr Mike Poland, a geophysicist with the United States Geological Survey. Hey! Hello! And Mike has monitored volcanoes all around the United States. He's currently heading up the monitoring for Yellowstone. But he told us that his closest call was back at our old friend, Mount St. Helens. It was in 2004, and Mike was just a newbie volcanologist back then.

Now, this mountain, after being silent for more than two decades, started acting up again, and Mike was helicoptered right up close to its crater to poke around. A helicopter left, and I remember thinking just like, man, I can't see into the crater. So if this thing does explode, I'm not going to see it coming, but I had a job to do. So I went to the station to work on it. And the first thing I saw actually was a mountain goat on the same ridge I was on just a few hundred feet away. And I remember all those stories and, you know, they're all sort of apocryphal that, you know, the animals know, right? Exactly, exactly.

Well, you've been dumped there like a lamb to the slaughter. All the ants have left the building. But I saw this mountain goat and I thought, I guess, you know, he's okay hanging out on this ridge. So I guess I am too. And for whatever reason, that relaxed me instantly. Turns out, the goat knew what was up. Mount St. Helens didn't end up blowing again this time. But we asked Mike, without a goat nearby,

how do we know if a big volcano like Yellowstone is going to get angry? Now, sometimes articles say that to find out when Yellowstone is going to blow, all you need to do is look at the last few times it's erupted and do the maths to see when it's going to fire off again. Now, if you do some loosey-goosey calculations around Yellowstone's last big three eruptions, which have happened in the last, say, two million years, it kind of looks like maybe it is overdue. But Mike says, don't do this.

Well, right there, overdue. No, uh-uh, wrong. Really? Volcanoes don't work that way. Mike told us that volcanoes don't erupt on nice, neat timetables. And if you do the maths correctly, it's not even overdue. He says that if you really want to know what's up with Yellowstone, you've got to monitor it. And luckily, he's got gadgets and gizmos aplenty to do it.

Like Mike uses GPS measurements to see how much the ground is moving around Yellowstone. And that's because, get this, when magma hits the rock above it, it can literally move the rock in a way you could measure. So you can imagine as magma begins to accumulate beneath the volcano, it pushes the ground up. It actually inflates like a balloon. Wow. It's like, it's like the ground is breathing. Exactly. They breathe. They, they inflate, they deflate, the ground rises and falls. They're also measuring vibrations in the ground and even gases like sulfur dioxide that could be seeping out of the volcano. They deflate, they deflate, the ground rises and falls. They're also measuring vibrations in the ground, and even gases like sulfur dioxide that could be seeping out of the volcano.

That's a sign that magma is rising. Something that's very easy to measure, so it sticks out like a sore thumb. But perhaps the most awesome thing that Mike's team is doing is looking at whether gravity is changing, and here's why. So let's say you're now on a volcano and you do a gravity measurement and you get a reading. And then magma accumulates beneath the volcano. You have just added mass. Because of that, the gravity pull in that area

increases ever so slightly. And that's something we can measure. Oh. In fact, just the other week, Mike was on site looking for gravity changes around Yellowstone. And what he detected? Wow. You can hear in his voice how nervous he is.

Just take a listen. Okay, minus one, minus two. Sounds good. I would say three, eight, eight, four, six. We were joking. He doesn't sound nervous at all. It sounds like he's reading off a credit card. And that's because for years and years, all their monitoring has shown that Yellowstone is fast asleep. No concerning gravity changes, no sulphur dioxide in the sky. Now, every now and then, they might measure a buzz in earthquakes in the area,

and this always seems to lead to a bunch of news stories predicting that doom is upon us. But Mike says that from all his team's other measurements, they can tell that these earthquakes are not a sign that Yellowstone is about to blow. Scientists can tell that the magma under Yellowstone isn't bubbling all over the place. It's mostly solid. And if it were going to erupt, all of that basically solid rock would have to heat up and become liquidy and explosive, which takes time. You'd also see other big things,

like one study estimated that the ground would be raised by hundreds of meters. So if Yellowstone was misbehaving or acting up, we would know? Yes, without a doubt. Occasionally, I get people telling me, yeah, well, Yellowstone can erupt tomorrow and you wouldn't know about it. No. No, not true. Yellowstone will not erupt tomorrow. For a system that's as seized up as Yellowstone to decide that it's going to erupt tomorrow, no way. It just doesn't turn on like that. I would expect at Yellowstone, if there was some sort of event that started really churning up the magma chamber,

maybe starting to remelt some parts of the magma chamber, we would have decades of warning. And Mike says that even if he does come to work tomorrow and start seeing some small changes that over the decades turn into big changes, that still doesn't necessarily mean doomsday is coming. Just because a volcano has had some major eruptions in the past, it doesn't mean that every time it erupts, it'll go berserk. Sometimes lava can just kind of spill

out. And in fact, in the last 600,000 years, every time Yellowstone has erupted, that's what's happened. The lava just kind of oozed out. And so Mike says that if Yellowstone were to erupt today... It's not something that would spread devastation throughout the region or the world. It would devastate the ground in Yellowstone National Park, the area that it flowed over. It'd be a bad day for a lot of deers. It would be a bad day. Well, even the deer could probably walk out of the way. I mean, the lava flows probably don't move that fast. All right. So all signs are pointing to we are good on Yellowstone. You can cross that off your ever growing doomsday list. But of course, this doesn't mean that other volcanoes won't mess us up in the future.

Because right now, there are dozens of volcanoes all around the world that have magma that's not locked and solid. It's smushy and kind of ready to blow. And while science can tell us, yes, these volcanoes are angry, right now, here's what it can't do. It can't predict the exact moment that a grumbling volcano will tip over into a kaboom. So it's likely that volcanoes are going to keep causing us trouble. But there is another side to them,

one that perhaps doesn't make for scary documentaries. And it's this. Life as we know it wouldn't exist without volcanoes. Billions of years ago, volcanic activity created our little blue dot as we know it by spewing out molten rock from the belly of the earth. They helped build continents. They also pumped out gases that helped create oceans and our atmosphere. Volcanoes basically put the mother in Mother Earth. And for Christian, who saw Mount St. Helens blow 40 years ago, he has a lot of respect for these fiery mountains.

Yeah. I still think about it. I still think about that awesome, crazy power and just remind myself what Mother Nature is capable of when she gets upset. That's Science Versus. Hello. Hey, Nick Delrose. Hey, Wendy Zuckerman. Our amazing intern at Science Versus.

How many citations in this week's episode? There are 102 citations. 102. You cracked it. Cracked the hundred. Do you have a favorite? A favorite citation? How can you choose amongst your children?

You really can't. And if people want to read these citations and find out more about volcanoes, where should they go? They can follow the link in our show notes to the transcript. Thanks, Nick. Bye. This episode was produced by Michelle Dang and Nicholas Delrose. With help from me,

Wendy Zuckerman, Rose Rimler, and Hannah Harris-Green. We're edited by Blythe Terrell. Fact-checking by Barbara Rodriguez. Mix and sound design by Sam Baer. Music written by Peter Leonard, Marcus Begala, Emma Munger and Bobby Lord. A huge thanks to all the researchers we got in touch with for this episode, including Brian Wilcox, Dr Mike Rampino, Dr Jasmine Scarlett, Dr Joe McConnell, Dr Rosalie and Dr. Thor Thorderson. A special thanks to the Zuckerman family and Joseph Lavelle Wilson.

I'm Wendy Zuckerman. I'll back to you next time.