Science Friday - Weather Advances, Listening to Volcanoes, Phragmites. Jan 25, 2019, Part 1

Episode Date: January 25, 2019

Your smartphone gives you up-to-the-minute weather forecast updates at the tap of a button. Every newscast has a weather segment. And outlets like the Weather Channel talk weather all day, every day. But how much has the process of predicting the weather changed over the past 100 years? Though many of the basic principles are the same, improvements in data collection, satellite imagery, and computer modeling have greatly improved your local forecast—making a five-day look ahead as accurate as a one-day prediction was 40 years ago. Richard Alley, a professor of geoscience at Penn State, describes the evolution of meteorology, and what roadblocks still lie ahead, from data sharing to shifting weather patterns. And Angela Fritz, lead meteorologist for the Capital Weather Gang blog at the Washington Post, describes the day-to-day work of a meteorologist and the challenges involved in accurately predicting your local weekend weather. When the Chilean volcano Villarrica exploded in 2015, researchers trying to piece together the eruption had a fortuitous piece of extra data to work with: the inaudible infrasound signature of the volcano’s subsurface lava lake rising toward the surface. Volcano forecasters already use seismic data from volcanic vibrations in the ground. But these “infrasound” signals are different. They’re low-frequency sound waves generated by vibrations in the air columns within a volcanic crater, can travel many miles from the original source, and can reveal information about the shape and resonance of the crater… and whether it’s changing. And two days before Villarrica erupted, its once-resonant infrasound signals turned thuddy—as if the lava lake had gotten higher, and left only a loudspeaker-shaped crater to vibrate the air. Robert Buchsbaum walks into a salt marsh on Boston’s North Shore. Around him towers a stand of bushy-topped Phragmites australis, an invasive plant commonly known as the common reed. Phragmites is an enemy that this regional scientist with the Massachusetts Audubon Society knows all too well. The plant, which typically grows about 13 feet high, looms over native marsh plants, blocking out their sunlight. When Phragmites sheds its lower leaves, or dies, it creates a thick layer of wrack that keeps native plants from germinating. Its stalks clog waterways, thwarting fish travel. The roots secrete a chemical that prevents other plants from growing, and they grow so deep they are nearly impossible to pull out. But this stubborn bully of a plant might have a shot at redemption. A recent study from the Smithsonian Environmental Research Center found that the very traits that make Phragmites a tough invader—larger plants, deeper roots, higher density—enable it to store more carbon in marshy peat. And as climate change races forward, carbon storage becomes a bigger part of the ecosystem equation. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

This is Science Friday. I'm John Dankoski. Ira Flato is away. Later this hour we'll be talking meteorology and hearing what volcanoes have to say. But first, it's not always easy being an ant. You're small, you're fragile, you're easily stepped on. If you leave the nest, you've got to worry about hungry birds, mammals, maybe clunky human feet. And if you thought that you'd be safe, deep in your big nest with all your friends, think again there's something there too, disguised by smell, snacking on hapless workers, and even eating your own. young. Here with a tale of horror and other short subjects in science, as Annalie Newitz, a science journalist and author based in San Francisco.

Antily, welcome back to the show. Hey, thanks for having me. So what is stalking these poor ants? It's a terrible story. It is a terrible tale of terror. So this comes from an article by a couple of scientists, Wendy Moore and Andrea DiGiano, and they were researching a typical ground beetle called O'Shea. Zana Lumulti. And it turns out that this beetle has a really unusual relationship with ants. It's not unusual for beetles to hunt ants, and a lot of beetles are predators. But these beetles

live with ants in oak trees throughout their entire life cycle. So the females lay their eggs in the ant nest. They disguise themselves by covering their bodies in smells that the ants recognize as friendly smells, because ants are blind and they kind of. and navigate the world through smell. And as these beetles grow older as they become larvae and then adults, they feed on the ants by piercing their abdomens and sucking the fluids out. It sounds terrible. So hold it.

How did they discover this particular beetle doing this particular thing? So these are scientists who were looking at beetles who are living kind of in concert with ants. And they discovered that this particular beetle. unlike others, wasn't just sort of chomping down on the whole ant. They were looking at the inside of their guts and sort of looking at what was in their stomachs, and they found that these particular beetles had this odd paste in their stomachs, which showed them that they had evolved specifically to suck the guts out of ants, and that also this gave them more clues about how much of the ant's, how much of the

beetle's life cycle was spent among the ants. And so they spent time in Arizona right at the border with Mexico, observing these beetles in their natural habitat in oak trees with ants and came up with a lot of data from that and then brought one of the beetle larvae home with them to observe it, eating ants up close. And the ants don't just get together and attack these beetles because they smell really good? That's right, because they have the ability to kind of cover their bodies with a scent. that the ants recognize as being kind of a home scent or a friend scent. Ants navigate the world by smell, and there are a lot of insects, beetles, mites, other creatures that sneak into ant nests all the time and disguise themselves with smell. It's kind of like putting on an invisibility cloak. And it's a great way to protect yourself if you're a beetle because ant nests are really safe.

All right. So let's move on from that somewhat disturbing story to a story about Twitter, which can in its own way be disdemeable. disturbing. It turns out that our tweets are kind of predictable. I guess this isn't news to some of us, but what are we learning about the predictability of our tweets? This is a really interesting story. So a couple of researchers, data scientists and psychologists, looked at the Twitter streams of about 950 people. And what they did was they took, I'll give you an example, like say you're Bob and you have a Twitter stream, you've tweeted a bunch of stuff. The question they had was, how easy would it be to predict your next tweet?

So they take all of Bob's tweets. They feed them into the algorithm that they're using, which is a predictive algorithm. And they find out that by looking at Bob's past tweets, they can predict with 53% accuracy what the first word of his next tweet will be. But that's when things get weird because then they started looking at all of Bob's closest friends on Twitter. So they said, all right, who are Bob's, who are the 15%? people that Bob tweets at the most.

We're going to call those Bob's friends. And if they look at the combined tweets of Bob's 15 friends, they can then predict the first word of Bob's next tweet with 57% accuracy. So it's actually more, like your friends' tweets are more predictive of what you'll say next than your own tweets are. And then it gets even weirder because that means, conclude the researchers that we can even predict what you might tweet if you're not on Twitter. We can predict what you might tweet.

If you're not even on Twitter, you might be able to tell just by looking at what your friends tweet. That's right. Because when Bob signed up for Twitter, we're just going to keep picking on Bob. Poor Bob. When Bob signed up for Twitter, Twitter said, would you like to upload your contacts list? And this is something that lots of social platforms do. It's not just Twitter. you know, Facebook does it, WhatsApp does it.

And so Bob uploads his contacts, and Alice is in his contacts, and Alice doesn't use Twitter. But she now is known to Twitter because they have her contact information. And maybe 14 other people also have Alice's contact information. So now, even though Alice is not a member of Twitter and has never tweeted in her life, those 15 people's tweet streams can predict what she might say next. And for now, you know, we're only predicting kind of unimportant words that people might say, but the researchers say that soon this kind of algorithm could predict important words, like how you feel about a presidential candidate or how you feel about a brand of soap.

And that's the kind of information that political parties want, institutions want, advertisers want. And that's why there's so much pressure to be coming up with algorithms that are even better at doing this. All right. Well, actually, that's even scarier than the ant story now. Now I'm worried about this, too. All right, we're going to get to one more story here. You found something interesting about what happens in our brain when we're enjoying music. So tell us what's happening.

So this comes from a study by neuroscientists who are actually just interested in whether our enjoyment of music is caused by dopamine, which is a neurotransmitter that's associated with lots of different kinds of good feelings and a sense of accomplishment and things like that. So what they did was they gave test subjects a common drug that's actually used a lot in Parkinson's disease. It's called Leva Dopa. And it's a precursor for dopamine that just allows dopamine to circulate more in your brain and be taken up by nerves in your brain. And so what they found was that people who were under the influence of Liva Doppa were likely to pay more money for music that they enjoyed than people who were not on Liva Dopa and people who had actually had dopamine dampened, dopamine transmission dampened in their brains. So basically, we have a drug that makes you willing to pay more money for music. But only, very quickly, only music that you like or any music?

Typically, this was music that people liked. So you couldn't get, you know, someone who hated country music to suddenly be willing to spend tons of money on country music. Okay. That's the code they still need to crack, I suppose, in the music business. That's all the time we have. I want to thank our guest once again, Annale Newitz, a science journalist and author, in San Francisco. Thanks so much for joining us. I appreciate it. Thanks for having me. And now it's time to check in on the state of science.

This is KERNO. St. Louis Public Radio Radio News. Iowa Public Radio News. Local science stories of national significance. A New England can certainly seem like a bucolic spot with those bushy reeds dotting the landscape, but those tall reed-like plants that we think of as quintessentially New England and a big part of the marsh ecosystem are actually an invasive species called Phragmites, and it's choking out life in the wetland. fragmites is tough to get rid of, and recent efforts have gotten even more complicated because of climate change.

Here's that story now is Barbara Moran, Environmental Editor at WBUR in Boston. Hi there, Barbara. Hey, how you doing, John? Doing well. So there's been a long campaign to get rid of Fragmites across New England and elsewhere in marshy areas. Why? Why are people trying to get rid of them? Yeah, it's funny because it's actually kind of a pretty plant. I know people would hate hearing me say that about it's sort of public enemy number one as far as invasive species in marshes.

And salt marshes are really important part of the New England ecosystem. And the phragmites is a really tough invader that can come and crowd out the native marsh species. I talked to Liz Duff when I was researching this story. She's been studying salt marshes for Mass Audubon for more than two decades. And she really laid out the case for why we should be getting rid of phragmites. And here's a cut from her. When there's less phragmites, it's easier, say, for migrating birds. So find a place to land.

It's easier for our native grasses to thrive. It competes for things like our golden rod, which is an important food for migrating monarch butterflies. So there's definitely disadvantages for having the fragmites around. So this is why people have been trying to get rid of them for years, but now there's some questions about whether or not we should just leave those fragmites in place. What are they finding? Yeah, this is really interesting. So I should say it's also fragmites is really, really hard to kill. You know, like they, when they try to kill it, they do stuff like cracking its neck open and dripping poison down with an eyedropper or they try flooding it.

And it often just comes back. So it takes a lot of resources to try and kill it. And the questions have been arising for the past couple of years about whether Phragmites might actually provide some useful, you know, what they call ecosystem services, especially with growing concerns about climate change. So what does it do? why might it actually help us come back climate change? Yeah, so it's really interesting. A study came out of the Smithsonian last fall by a scientist named Ian Davidson, and he found kind of ironically that the same stuff that makes Phragmite's such a tough invader,

the fact that it's really tall, it has deep roots, it grows really close together, all these things actually make it sequester carbon better than the native species. So fragmites can take carbon out of the atmosphere, and when it decomposes into peat, it actually can sequester carbon better. There's also this other evidence that phragmites just because it's so bulky, that's such biomass that it can buffer these marshes against sea level rise. So these are a couple sort of maybe pluses for this invasive species that people are starting to sort of look at, make look at this plant a little differently. So maybe make friends with the enemy over time, the enemy that they've been trying to get rid of for all these years. Exactly. I know. And they're not quite there yet. I mean, everybody was very quick to say, well, don't go out and plant phragmites. You know, we're not there yet. Biodiversity is still the most important thing for marshes. But, you know, they're starting to talk. You know, we're living in this really high CO2 world. Climate change is advancing more quickly than expected. And we're really going to have to start looking at things in different ways as we go forward maybe. Barbara Moran is environmental editor at WBR in Boston.

She's been following this story for us. Barbara, thanks so much for joining us. I appreciate it. Thanks. It's great. When we come back, your local forecast, how different is it today from what it was, say, 100 years ago? Stay with us because there's a 100% chance we'll be right back after the short break.

This is Science Friday. I'm John Dankowski. The American Meteorological Society is celebrating its centennial this year, and a lot has changed in the past 100 years. You know, little things like computers, satellites, the Internet. So how have these things changed your local forecast and what meteorologists do day to day? And as the climate changes, how well meteorology have to adapt? Joining me now is Richard Alley.

He's the Evan Pugh Professor in the Department of Geosciences at Penn State University and co-author of an article this week in the journal Science, looking at the history and future of meteorology. Richard Alley, welcome to Science Friday. Thanks for joining us. Well, thank you, John. It's a pleasure to chat with you. your listeners. Also joining us is Angela Fritz. She's an atmospheric scientist and deputy weather editor for the Washington Post. Thanks so much for joining us as well, Angela. I'm so happy to be here.

Our number is 844-724-8255. That's 844-Sai Talk. If you've got big weather questions for our guests, please don't ask them, will it rain today, but bigger questions about mirrorology. And there's a lot to talk about. Richard, I'll start with you. How far have we come in 100 years? Oh, just fantastically. I mean, you know, 1938, a hurricane came storming ashore from about where you're sitting there in New York across the way to Rhode Island. It killed about 600 people. Nobody knew it was coming. It came screaming out of the Atlantic with virtually no warning. When I was a kid, you had a day's warning, and now we have three days.

No warning, you die when the storm hits. A day you might be able to get out of the way, but if it's a big city, you're not going to. you don't have time to empty the city. Three days you can do it. And so as more and more people are in the firing line of big storms, fewer and fewer people have to die. And it's not just big storms. It's just the day-to-day accuracy to, Richard.

I mean, you're able to just tell a lot more about the weather than you used to. It's beautiful. So the people who work hard on this, and Angela knows this very well, but they have developed metrics of how well forecasting is doing. and the improvement in forecast skill is really, really clear, it's really obvious because they figured out how to do it better. Angela, tell us about that. How much do you think accuracy has improved over these last hundred years? Actually, I think in Richard's paper, there's a really great stat in there that we like to cite a lot. Richard, is it five-to-one? A five-day forecast now is as good as a one-day forecast.

used to be mid-20th century. Is that right? Yes. Yeah. So it's incredible. And, you know, people like to rag on forecasters and meteorologists all the time. But if you actually look at the statistics, we kind of get it right a lot. Yeah. One of the things that have actually helped to improve this so much. I mean, Angela, if we look at, you know, a one-day forecast versus a five-day forecast, that is a big jump. And, of course, we can tell weather pretty accurately 10 days out. I mean, what exactly led to these improvements?

There are two big things that we always kind of point out. And the first is just so much more data. We have a lot more observations. So satellite data, more things like thermometers and anemometers on the ground. And so that feeds more information into these weather forecast. models that people always hear about, and that's what helps us determine what the weather is going to be. And then on top of that, supercomputers, you know, our computing power has gotten so much better, and that allows us to predict with better accuracy and a higher resolution.

Just like your TV has a higher resolution, our forecasts get a clearer picture with more computing power. And so those two things combined have really helped us push forecasting into the 21st century. So more data, bigger computers to crunch all that data. But also you still use things like weather balloons, Angela. A lot of the same old tools that you've used for 100 years are still out there. Absolutely. And that is part of the data that we're using. And we still look at that weather balloon data to figure out what's going on in the atmosphere.

the old tools are still important and reliable, and the things that we knew about the atmosphere back in the 50s still hold today. So our basic knowledge of how the weather works still holds, and that's what those weather models are built on. It's built on fluid dynamics. It's all physics. And what we're able to do now is really model that physics and crunch all of the numbers in a very precise way and as close to accurate as possible

because of the ability to have so much data and the computing power. And as Richard talks about in this paper, a special thing called data assimilation. Richard, maybe you can talk a little bit more about that. Sure. So they have, the angel is completely correct. They've also made the models better. But then how do you get the modern state of the atmosphere into the model? How do you let the model know what we know?

So to get the model up and running so it goes through the present as accurately as possible and into the future. And this involves these very sophisticated techniques of basically letting the model interpolate between the data and letting the data bring the model back to reality. and this cross-talk between data which are necessarily incomplete and models which don't know everything has really given us the ability to know better. The faster computers then let them tweak the data a little bit within the uncertainties and run you an ensemble of future

so that Angela can tell you what the uncertainty is as well as what is likely to happen. And so all of these put together have been necessary. It really did need better models, more data, better ways to put them together on faster computers, and then one more piece, which is it needed really good people who can take what comes out and make it useful. And it's easy to overlook Angela and a whole bunch of people like her who make these data useful for you, but they are an essential piece in the answer. Yeah, those people who, as she said, sometimes get a bad rap.

Maybe we'll come back to that in a little bit. We're talking about the past, present, and future of predicting the weather. If you want to give us a call and ask a big weather question, 844-724-8255 or 844 SIE Talk. Richard, tell us a little bit more about how this entire forecasting system is set up. This is kind of a public-private partnership? Absolutely. So the backbone for a very long time has been the public collecting data and running the models, making forecasts, and making them useful.

There actually is scholarship on the payoff on this, how much good that society gets out of their investment in weather forecasting. And the answer is that between three and ten times payoff, an investment that pays 300 to 1,000 percent. So this has long been going on, that we invest in this. It's a public good that needs to be made available for everyone. And then what has grown up is a lot of people have said, we can take what the government produces, and we can make it even more useful to you. And so there's an additional world of targeted forecasting, targeted communications, of taking what comes out of this big public effort and making it a public private effort. A whole lot of businesses with really hard bottom lines that have to pay off are hiring weather forecasters because it pays all. They can use that knowledge in ways that are good.

And we have students that come routinely from the military because the military knows they need good forecast too. Marty has a question along these lines calling from Ellensburg, Washington. Hi there, Marty. You're on Science Friday. Hi. Hi. What's your question? My question is, like, we have all these different places to get weather forecasts,

And I'm wondering if they're all using the same basic information from the U.S. Weather Service or if they all have their own kind of information sources. That's a great question. And Angela, maybe you want to pick up on that because I think people are confused. There's so many places you can get a weather forecast these days. Yeah, and Marty's question is actually something we get asked a lot. You know, the basic backbone is all the same, but the way it's applied might be different. So there's the National Weather Service, there's the app on your phone, weather channel, AccuWeather, and then there's your local TV station.

So, you know, the data that comes in is all the same, and then the models, everyone gets to see the models. Some of the private companies have their own weather models, and some people have, you know, give that forecast a personal touch. So it's unlikely that you're going to see the same forecast across every single app or TV station. And so what you actually have to do is I always just recommend finding a forecast outlet that you like, that you think is accurate, that you can relate to, and that you can trust. Because it's important to get the weather right day to day, but it's also really important to find some, you know, a trusted source for when the weather's going to be really bad that you can go to and get your emergency information from them. So that's always my recommendation.

Speaking of emergencies, and I think Richard touched on this earlier, but Angela, especially in hurricane season, we hear about these different models, what they are, why they're different. Maybe you can just explain a little bit more, especially when it comes to predicting something that's really as devastating potentially as a hurricane. Sure. So all of the different models, and, you know, the U.K. has their own set of models, the Europeans do, Canada, the U.S., they're all trying to model the basic physics equations of the atmosphere in slightly different ways. They all kind of have different approaches to answer the same questions. And within those models, they also run them several dozens of different times with just very little tweaks to their initial conditions, so their starting points. Because, like Richard said, we don't know exactly what the atmosphere, what the state of the weather is at this very moment.

It's impossible to know exactly what it is. So accounting for the fact that we don't know, and we know that there's going to be some error there, we run it to get that chaos effect into it, you know, to get that butterfly flapping its wings and get a little chaos in there so that it generates that spaghetti string output that you see during hurricane season, you know, with all the squiggly lines that you'll see on TV. It looks a little weird, but what that actually does is what we're going to. get out of that as a consensus? Because down the middle of that, you know, a group of squiggly lines is an average. And what we have found over the past couple of decades is that the most likely reality, the most likely good forecast is right down the middle. So if you can take several hundred different forecasts from several hundred different models, it's probably,

what actually is going to happen is probably really close to what's right down the middle. And that has been where weather forecasting has been going over the past couple of decades. I'm John Dankowski, and this is Science Friday from WNIC Studios. Richard Alley, I would love to ask you about some of the big, impacts on our world that really good weather forecasts have. So it's not just whether or not you take an umbrella out or even whether or not a bad storm might hit, but there are day-to-day economic impacts that are felt by either good weather forecasts or bad weather forecasts. What can you tell us about that? Right. So it is very clear that we use weather forecasting in a lot of ways.

We check it a huge number of times, and it's beneficial to us, which is why we do this, and this is why businesses invest. What's coming now is the ability to take the weather forecast and to use it to forecast other things that you really care about. So when they give you the hurricane track, they don't just say you will get hit by the hurricane, but they also tell you how high will the storm search be. Do you really need to get out a ways inland? And that comes from taking the weather forecast and coupling it to a targeted model that looks at how the ocean responds to the winds and the pressure. They will join that to a flood forecast, which takes the weather forecast and the rain and puts it into a model of how water runs off the land, how it gets into the

river, how fast the river rises. And now you have river experts and ocean experts who are taking the weather and using it to tell you what you can do to make yourself safe. We have a world now that sea ice is thinning in the Arctic. When the Arctic had a huge amount of sea ice all the time, nobody in their right mind went up there unless you had an icebreaker or a dog slack. And now you have a military ship or a ship full of cars being shipped across the Arctic Ocean or a ship full of tourists. And as soon as you have people up there, the sea ice does regrow in the winter to some extent. And now you can get a ship trapped. And you need a sea sea ice forecast, and they can do sea ice forecast. They can actually forecast bird migrations

now. The birds want to go at a particular time of the year, but they want to go when the weather's right. They want to ride the wind and not fight it, and so you can actually combine knowledge of biology with knowledge of the weather to tell the wind turbine operator, hey, there's a huge flock headed your way. Shut it down for tonight. I have to ask, can we just have a couple minutes left, So, Angela, you know, as Richard brings up sea ice melting, the specter of climate change hanging over all this. How much more difficult does that make your job right now? How much more difficult could it be in the near future? I think that we're seeing extreme weather get worse, and we're seeing things that we haven't seen in the past.

In terms of how difficult it is to predict, I don't know. know if it's making forecasting more difficult, I think it's just that the events that we're seeing are more extreme and maybe less believable in advance for some people. And Richard, you can tell me if I'm wrong. But I think that overall the physics of the atmosphere, you know, fluid dynamics is not going to change unless something really bad happens. Yeah, Richard, I'd love your thought on that. A little less than a minute left. Go ahead. Right.

So the physics is right. It works. The climate change is making it harder in the sense that if you get more rain, the flood gets harder to forecast because it comes faster. But they're doing a great job of it, and they can do this. The physics works, and it's real. And you sound very enthusiastic about the future, Richard. It's fantastically bright. If we keep the investment going, the payoff is very clear.

The public partnership partnership is very clear. It's moving us forward. We can do great things. But it takes a big investment, which is, I think, maybe a topic for another day. Richard Alley, he's the Evan Pugh Professor in the Department of Geoscience at Penn State University. Thank you so much. I appreciate it. Thank you. A real pleasure.

Thanks also to Angela Fritz. She's an atmospheric scientist and deputy weather editor for the Washington Post. Thank you, Angela. Thanks for having me. When we come back from forecasting weather to forecasting volcanoes, what we can learn from listening to lava tubes. This is Science Friday. I'm John Dankowski. If you've been following our winter book club, you know volcanoes are high on the list of topics that we're nerding out about in the next few weeks.

The Club is tackling NK. Gemison's Apocalyptic Book The Fifth Season, which follows a world constantly in upheaval from earthquakes and volcanoes. We've got a Facebook discussion group, weekly newsletter, and a lot more. It's not too late to join the fun. Check out everything you need to know on our website, ScienceFriday.com slash book club. But in the meantime, volcano forecasters have a lot of tools for figuring out when a dormant volcano. is getting active and when it might actually erupt, seismic monitoring, gas emissions, and maybe someday the vibration of air masses in the volcano's crater. Those vibrations are very low frequency and silent to our ears, but with the right microphones and the right processing, that sound becomes data that can tell us about the shape

of a crater, the location of lava at the bottom, and a lot more, something a little bit like this. Here to explain more is Jeffrey Johnson, Associate Professor of Geoscients at Boise State University in Idaho. Science Friday. Thanks for joining us. Thanks very much for having me. So I just played a sample of some volcano vibrations. What does it actually sound like to our ears, though? And maybe you can explain what we're listening to. Right. Well, what we just heard was a recording from a volcano in Chile called Villarica over the course of about five days. And you heard it in just a few tens of seconds.

But what you might have been able to detect is a change in the timber and both frequency of those sounds. Now, what we actually recorded was infrasound, low frequency sounds below the threshold of human perception. But when we speed those up, we can detect them and perceive something with our brains. Okay, so a little too hard to hear, but you're able to make it something that we can hear. How is infrasound different from vibrations from seismic activity? Well, volcanoes will produce both seismic energy that propagates through the ground and when activities occurring at the surface of the volcano, such as for explosions, we also radiate sounds into the atmosphere.

Volcanoes produce sounds that are both audible and subaudible, and it's these subaudible sounds that are so much more energetic, and that's the focus of many of our studies on the subject of volcano acoustics. We focus on infrasound energy below 20 hertz. The very low frequencies that we're talking about can travel quite a distance, can't they be sensed a very long way away? Right. So low frequency sounds have the capability of propagating long distances with low attenuation, which is why you have foghorns and not fog whistles when you want to listen to boats that are long ways away.

Volcanoes just so happen to produce a lot of infrasound. Many of them produce sounds about 1 hertz, which is something like five octaves below the threshold of human perception. And these low frequency sounds can attenuate very slowly and be recorded regionally or even globally in some cases. Explain a little bit about what the volcano is doing. to create these sounds in the first place? What exactly are we hearing happening? Well, the sounds we just listen to come from a volcano that has a giant crater that extends down from the crater rim

down to a lava lake, about 100 to 150 meters below the crater rim during most regular times. And this lava lake is bubbling away. It's exploding. We call these explosions strombolian explosions. And every time there's a burst, there is a sound wave that's radiated up and through this crater and can be recorded many kilometers away from the summit.

What we've noticed at this particular volcano is those infrasounds from those explosions have changed over time, and we are relating those changes to the rise of the lava lake within the crater. Maybe we can listen to that sound one more time again. This is from the volcano of Villarica in Chile. Let's listen.

Maybe you can explain for our listeners a little bit more what exactly we're listening to there. I mean, what is it your hearing in that sound that is meaningful to you? Well, we're listening to explosions recorded with infrasound, but sped up into the audible domain. And one thing you might have picked up is that the frequency content changed, and at the same time, maybe a little bit more subtle, the timber of these sounds changed. And so as this lava lake is rising up within the crater, we are effectively shortening the tube of this acoustic resonator. And that's creating these higher frequency sounds.

Our study from 2018 analyzed another aspect of the sound, however, and that is this thing called the quality factor, the amount of resonance that those sounds are exhibiting. In other words, in the early portion of the sequence, this pipe was resonating very nicely, almost like a musical instrument. And towards the end of the sequence, as the lava lake rose to within 50 meters of the crater rim, the resonance was gone. And it was just these explosions that sounded like thunks. Sounded like thunks, and they sounded like thunks because why? Well, volcanoes as musical instruments only works when the crater shape is of a certain form. And so in the case of Vioreka, we had this giant shaft, 150 meters deep, about 60 meters wide, and that was able to very effectively trap acoustic resonance.

That was oscillations of air masses within the system. There was a large impedance contrast at the atmosphere crater interface. As the lava lake rose, the sources that are occurring at the lava lake surface are now being projected out into the atmosphere and they're not being bounced back or reflected at that crater opening. It has everything to do with the geometry or shape of that flaring crater. We have another recording here. This is a signal from an Ecuadorian volcano called Kodhopoxi. Let's listen to that. So that actually sounds very much different. It almost sounds like a human breathing or maybe waves on the ocean. What are we listening to there?

Well, there are a few tricks that were done to make that infrasound audible. But suffice to say that what we were listening to right then was an infrasound signal from this volcano called Codopoxi that was played in near real time. And the crazy thing about Cotopoxy is the beautiful signals that this volcano musical instrument is able to create. By beautiful, I mean if you were to look at the waveform, you would see a five-second oscillation that endures for something like a minute and a half. So what's actually happening is you're exciting this crater, this giant musical instrument with some source at the bottom, and you are causing an oscillation to occur for more than one minute. And, of course, these oscillations are inaudible, but with our specialized microphones, some eight kilometers away from the vent, we're able to pick up on these signals and use them to determine the size and the dimensions of that volcano crater. So you're able to use this to determine size, volume, know a little bit. more about what's happening inside. How can this help us predict eruptions or events that are

happening that could obviously be problematic for humans living nearby? Well, the code epoxy example was a case study where we recorded this beautiful signal that wasn't changing over time. So for six months in 2016, we recorded the same signal again and again and again. That allows us to say something about the rather stationary behavior of that volcano. In other words, was happening down at the bottom of the crater, and we don't quite know what that was, was constant. That process was occurring again and again. In the case of Vioreka, we were alerted to these changes in the nature of the infrasound, which became suddenly much more interesting.

Volcanoes, when they maintained their background state, are well-behaved volcanoes. When that background state changes and you see signals that evolve over time, that's the time when you want to pay attention. Would it make sense to be able to listen to volcanoes, to be able to monitor infrasound at volcanoes all around the world? Are some volcanoes better candidates for this sort of experimentation than others? Indeed, scientists are listening to volcano infrasounds all over the world now. It's become an established component of the volcano monitoring toolkit. And there are dozens of volcanoes right now where infrasound data feeds are complementing the seismic or the deformation or the gas remote sensing. technologies. And many volcanoes do produce very interesting infrasounds, which are being tracked

in real time. One thing to mention, though, is that unless a volcano is actually doing something at its surface, the infersound is less interesting. And in that case, we look at the seismicity, the earthquakes occurring beneath the volcano's surface to infer processes. I know that it's probably not only volcanoes that emit infrasound. So what else can you learn? Are there other things that we can study aside from volcanoes by using sound? Yeah. Sure. Infrasound remote sensing is being used for a number of geophysical source studies.

And some of the most interesting studies I think are happening right now, our group at Boise State University is focused on this, is using infrasound to track and detect snow avalanches. Now, snow avalanches produce a lot of energy that is audible, but most of its energy is beneath of human perception, right around 5 Hz. So if we're listening to these processes with infrasound, we can detect when avalanches have occurred, even when we can't see the slopes. Jeffrey Johnson is an associate professor of geosciences

at Boise State University in Boise, Idaho. Thank you so much for talking volcanoes with us. I really appreciate it. Thanks very much. Now, speaking of craters, our second season of Science Diction kicked off last week. This is where we dig really deep into the roots of science words and tell you all about it.

And the first word we looked at, yes, Crater, which, it turns out, has nothing to do with volcanoes, at least originally. Here to explain why is SciFRI Digital Producer and Master of Science Diction, Johanna Meyer. Johanna, welcome to Science Friday. Thanks so much for joining us. Hey, John. Thanks for having me. Okay, so where did Crater come from, if not volcanoes? So take a look at pretty much any depiction of an ancient Greek symposium.

You'll see a ton of guys hanging around, philosophizing, whining, dining, and nearly always in the center, there's this urn, position. positioned really prominently. That's called a crater. It starts with the K. And the crater was super essential for symposiums because that's where they would mix wine and water. Hold it. They'd mix wine and water. I thought that they just wanted the wine without the water.

I know. That sounds very blasphemous to us today. But actually, wine in ancient Greece was aged in these clay or leather containers that resulted in a really acidic taste and also a much higher alcohol percentage. We're talking about 16%. The stuff that we drink today is around 12 or 13%. So the ancient Greeks actually considered it really barbaric to drink the undiluted wine. Oh, okay.

So it wasn't cool to drink straight wine. I get it. So how did we start using this word to talk about volcanoes then? Since about the 1600s, people have been using the term to describe pretty much any bowl-shaped depression like you would find in that ancient urn or in a volcano crater today. And actually, fun fact, it was Ralph Waldo Emerson, who was the first person to apply the word to lunar craters. Really? Really? Yeah.

I was surprised to learn that, too. That's really interesting. Okay, so I introduced you as our science diction wizard because you're rounding up the science origins, a tons of words. I'm assuming you've got a lot to work with. That would be an understatement. Science is, it's everywhere. It's baked into the words that we use. It's encoded in the language that we speak.

There's no shortage. I just need to remind you. I'm John Dankowski. This is Science Friday from WNYC Studios. And we're talking about science diction. Maybe you can tell us how people are going to learn more. more about science diction. Yeah, just go to science friday.com slash science diction. We send out a newsletter every week that looks into the scientific origin story behind one specific word, so you can

sign up there. Okay, we talked about crater already. What's on tap for this week? This week we're talking about Spanish flu, which is a total misnomer that has endured for a century. Okay. It's endured for it. It has nothing to do with Spain? Not really. It has a lot more to do with World War I. Oh, okay. So when we say the Spanish flu, what we're actually talking about is, it's about is the 1918 flu pandemic, which was devastating and wiped out. I'm sorry, a third of the world was infected. 50 million people at least died. So by the time that this pandemic surfaces in 1918, France, Germany, the U.S., a bunch of other countries were already embroiled in World War I. One country that was not was Spain. So because Spain remained neutral, that meant that they had much

greater freedom of the press. They weren't subject to wartime censorship rules like the U.K. They weren't worried about keeping morale up amid reports of great casualties among troops and camps. So it was a newspaper out of Madrid that was the first to publish a story about the flu outbreak. They got slapped with the name Spanish flu, and it stuck ever since. So what you're telling me is because Spanish newspapers did such a good job breaking the story of the Spanish flu. It's now called Spanish flu. Pretty much. It's kind of unfair, actually. It seems a little bit unfair.

What about the second part of that? Influenza. That's a really interesting word. Where does that come from? So before we had any understanding of epidemiology or virology, ancient people believed that the stars and the cosmos would flow into us and influence our lives. And actually, influenza means influence in Italian. So the idea was that sickness, like any other unexplainable event, was due to the influence of the stars. And they just went ahead and called one of the most common ailments, influenza.

So the influence of the stars is what gives us influenza, even though, so it's not a medical term at all. It's really, it's a mystical term. Totally. Yeah. This is why I like science diction. Thanks so much, Johan. I really appreciate it. Thank you, John.

Johanna Mayor is SciFry Digital Producer and head of our science diction project. And you can learn more on our website. It's science Friday.com slash science diction. Okay, one last thing today. Ira talked about this last week. He's on a trip traveling through Southeast Asia. And as he's traveling, he's looking around. He's trying to find cool stuff for us.

So he sent an audio postcard from his first stop, and here he is from the northern part of Vietnam. I'm here in Halong Bay. He's an extremely biodiverse site with many ecosystems, including mangrove forest, sandy tidal flats, coral reefs, caves and lagoons, and these giant limestone casks that surround the area. Gorgeous to look at. I can almost imagine Ira being there. He explored one of the caves inside those giant. giant limestone karks, and he said it was one of the most magnificent natural wonders that he's

ever seen. I hope he's having a great time. Hopefully he sends some pictures along. I know he'll be back in a couple of weeks. He's going to be sending us more of these little dispatches from Southeast Asia along the way. Charles Bergquist is our director. Our senior producer is Christopher and Taliyata, and our producers are Alexa Lim, Christy Taylor, and Katie Feather. We had technical and engineering help today from Rich Kim, Sarah Fishman, and Kevin Wolfe. We're active all week on Facebook. We're active all week on Facebook, Twitter, Instagram, all the social medias. And if you've got a smart speaker, ask it to play Science Friday, wherever you want. Every day now is Science Friday. You can email us. The address is SciFri at ScienceFri.com.