
How refrigeration transformed civilization, why volcanoes are essential, and a better way to end arguments.
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B
People were seriously against it. At first. They were afraid of it. People thought this was zombie food, undead. And they didn't trust it. And quite right, because they no longer knew how to know whether it was fresh or not.
A
Also, there's something in every woman's purse that probably needs attention. And volcanoes. You know what they are, but you may not know a lot about them. They're really fascinating.
C
One of the things that fascinates me about volcanoes is we would not be here, I don't think, as a species, if it was not for volcanoes. The gases coming out of volcanoes help to maintain our atmosphere over geological time.
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All this today on something you should know. If you and I were to meet on the street, which would be lovely, there's an excellent chance that the clothes I would be wearing would be from quints. And if you asked, I'd be happy to tell you about them. You know how when you discover a brand and suddenly you keep talking about it to people? Well, that's become me with Quince. Originally, months ago, I ordered a few things for myself. Their pants and some Polos, cashmere sweaters. And right then I knew. I mean, the quality was so much better than I expected. What I like is their stuff feels elevated without feeling fussy. Their linen shirts and pants are great this time of year. Light, breathable, comfortable, but you still look put together. I just ordered some jeans recently too, and they've immediately gone into regular rotation. And then you see the prices and it almost doesn't make sense because Quints cuts out the middleman and works directly with ethical factories. So you're paying for quality, not some big giant markup. Honestly, I recommend quints to people all the time and I'm recommending it to you. Elevate your summer wardrobe. Go to quince.comsysk for free shipping on your order and 365 day returns now available in Canada too. That's Q-U-I-N-C-E.com sysk for free shipping and 365 day returns quince.comsysk something you should know Fascinating intel, the world's top experts and practical advice you can use in your life today. Something you should know with Mike Carruthers. Hi there. Welcome. I want to start this episode by offering up some really good advice that will make you better at resolving any conflict. And it comes from a gentleman named Jim Farrell who wrote a book called the Anatomy of Peace. You see, in any conflict, you've got a couple of things going on that make it difficult. Number one, no one in a conflict thinks they're wrong. So trying to convince someone they are wrong, while that may feel like the right thing to do, rarely moves the conversation towards a resolution. In fact, it often makes things worse. The natural tendency in a conflict is to ask at some point, so how do we fix this? The problem with that question is that you're trying to fix something that has already gone wrong. It's already broken. That's not always possible or even desirable. A better question might be what can we do to help things go right? That steers the conversation towards a more permanent solution. Understanding these two concepts and putting them into action can make anyone better at resolving conflict. And that is something you should know. There is this invention, this technology that you interact with every day. You probably don't give it much thought, yet it has really changed the world, significantly more than you probably realize. And that invention is refrigeration, artificial cold. And yes, having a refrigerator in your kitchen is wonderful. But like with any technology, there are problems too. Here to help you understand how your refrigerator changed your life is Nicola Twilley. She is a writer, frequent contributor to the New Yorker, host of the podcast Gastropod, and author of the book Frostbite how refrigeration changed our food, Our planet, and ourselves. Hi Nicola, welcome to something you should know.
B
Thank you for having me.
A
So let's start with just a real quick history lesson here. When did refrigeration become a thing for people?
B
Well, so humans have noticed that cold kept food good. Since humans noticed things, there are examples of Paleolithic people using ice pits to keep their mammoth fresh. The the trick was no one could make cold until really recently. And so people didn't see cold as a very useful way to preserve food because natural cold was so unreliable. And it's not available everywhere and it's only available in the Winter. So you, you just didn't rely on it. You people used ice to make ice cream in summer or to make wine slushies. It was a treat. But they didn't rely on it for, you know, shipping meat across the country. When a scientist, a guy at the University of Edinburgh, first figured out how to make artificial cold, it was seen as a party trick. No one knew what to do with it. And it's actually really, really very recent, 150 years only that we've actually sort of cold commercially to ship food around the world.
A
Isn't that amazing that it's only 150 years old and yet it is just part of everybody's life every day in this country? And what about freezing? Are refrigeration and freezing all part of the same development of technology? Or are they two parallel paths of two different things?
B
That's a good question. They are obviously similar. In both cases, you're reducing the temperature. And so basically by taking energy out, you're slowing things down. The way refrigeration works, the way cold works, is it slows things down. So the bacteria that would be, you know, metabolizing and reproducing and turning your food bad, they're just growing more slowly. Everything happens more slowly in the cold. And so that's true of both. But freezing goes a step further by locking up the water, and without water, then all of those processes that would lead to decomposition just basically stop. So they're parallel but with a slight tweak.
A
The same people working on it, or did they show up in different spots and then sort of get merged together in the refrigerator freezer?
B
Oh, yes, good question. Very different people working on it, actually. So at first, refrigeration came first, just lowering the temperature. And it was actually an Australian printer who was the first to come up with a working refrigeration machine and sell it. And the place he sold it to was actually a brewery, one in London and one in Australia. Beer brewers, lager beer brewers were the pioneers in refrigeration because it's very hard to make lager beer. The yeast doesn't like being too warm in the summer. You really need refrigeration. So they were the ones who said, hey, new technology works for us. So that was happening in the mid-1800s. Freezing was a whole different set of problems because the thing about locking up that water is it forms ice crystals and those ice crystals can damage cell walls. Everyone's experienced this. Try and freeze a strawberry. It's very hard to do. It's Sort of mushy when it comes out. That's the effect of those ice crystals breaking down the cell walls. And it took Clarence Bird's Eye to figure out that if you froze things super quickly, you could get around a lot of that breakdown and keep the texture relatively intact. So, yeah, they operated separately. And for a long time people didn't have freezers. And then for a long time, they didn't have combined fridge freezers. And so they, although they work roughly in the same way, they only kind of met in our kitchens relatively recently, post war.
A
Isn't that interesting that the two things happen differently? And Clarence Bird's eye, I mean, he's kind of a legend, and his name is still on, I think, a lot of frozen food. And he was kind of the big pioneer in freezing food. The way you just described that made it work.
B
He was. But you know what he did? He froze a load of food and then he realized, oh, wait, I have no way to distribute this. Stores have no way to sell it, and customers have no way to store it at home. So that's one of the interesting things about this whole technological development, too, is that everything has to come along at once. If you don't have anywhere to keep your frozen fish stick at home, then there's no point having a fish stick.
A
Well. Right. Well, it's also kind of like who's going to buy the first telephone? There's no one to call, but. But somebody has to go first. Somebody has to be. And then it kind of stumbles along until it finally clicks.
B
And then we're all. Now you get to the stage where we're all locked into this, and it seems completely weird to imagine even living without a fridge or a freezer.
A
So I have heard that a lot of the food we buy at the store that's, you know, fresh produce actually sits in refrigeration for weeks, months, maybe years before it gets to the store. Is that possible?
B
It is indeed possible. If you go to the store in June or July and you buy an American apple, it's probably coming up on its first birthday. And the reason for that is really simple. Apple harvest starts in late August and runs maybe through November. So think about it. That apple has to be getting on a bit. If you're buying it in the store in June. I just. Most people don't think about it. But produce has seasons yet we can buy it all year round. And apples are one of the most interesting, actually. They were really one of the first pieces of produce to be successfully refrigerated in this way. And the life extension technology we use for apples is, well, to mix my metaphors, bananas, because it relies on not just making them cold and slowing down their death that way. And by the way, the apple is still breathing all the way up until you eat it. The apple is still breathing and burning through its own internal resources. And the trick with slowing that down is just to sort of sedate it and have it take as few breaths as possible on its way to you. Now cold will do that. The other thing they do is also just reduce the oxygen levels. So the apple is sitting in very, very reduced oxygen levels in the most sophisticated warehouses. It's actually controlling the oxygen levels itself. It's a dynamic system that adjusts to how fast the apples are breathing in and out and controls the levels with it. And they just sit there in the dark in these oxygen star cold environments, breathing very, very, very, very slowly. And then you buy them nine, 10, 11 months later.
A
See, I've always thought that the reason you could buy apples in the springtime was because probably somewhere else in the world they grow apples in the springtime and they grow it. It's like it's five o' clock somewhere, it's harvest season somewhere and so that's where the produce comes from.
B
Well, that's also true. I mean, so if you, you can buy an American apple in the stores right now and it will have been stored under refrigeration since last harvest season. It's also harvest season somewhere right now and guess how those apples are getting to you? In a refrigerated shipping container. So either way, it's refrigerated.
A
Our topic is refrigeration, artificial cold and how it has changed your life. My guest is Nicola Twilley, author of the book how refrigeration changed our food, our planet and ourselves.
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B
This is the part I found actually the most surprising, along with how recent refrigeration is, is that people were seriously against it at first. They were afraid of it. And if you think about it, it makes sense. Before, if. If you saw a fresh chicken, you knew it had to have been slaughtered a day ago or that day. Now, here was this new technology where the chicken could look fresh, but it could have been slaughtered a year ago, 10 years ago. I mean, what is. And people thought this was zombie food, undead, and they didn't trust it. And quite right, because they no longer knew how to know whether it was fresh or not. You know, fresh used to mean something. And if. If your food was older than a day or two, you had to have preserved it in some way that would have changed its physical appearance. You had to have dried it, smoked it, you know, canned it, done something that would let people know how old it was. And suddenly the fridge comes along and changes all of that. And one of my favorite moments is the cold. You know, the. The Egg Warehousemen's association was really afraid that Congress was going to sort of step in and set really short limits for how long food could stay in cold storage warehouses, because the public was agitating for that. And so they ran a big PR campaign. Refrigerated food is safe. And they held these banquets. The first one was in Chicago, where everything on the menu had been refrigerated. And, you know, today you'll go to a restaurant and you'll see, oh, this is grown by this farmer at this place. On that menu at the cold storage banquet in Chicago, it said, this chicken has been stored for six months at Booth's Cold Storage at, you know, 53rd West 22nd Street. It listed the cold storage warehouses. And it was a giant PR attempt to try to prove to Americans that refrigerated food was safe.
A
It must have worked, slowly but surely.
B
I mean, even after that first meal, there was a headline in the Journal of the American Medical association the next day. This means nothing. You know, what happened, honestly, was a woman called Polly Pennington made refrigeration scientific. She did the research. She was hired by the federal government to figure out how food could be refrigerated safely, what temperature things had to be stored at, for how long to be safe. And she was an absolute pioneer. She was hired at a time when women weren't hired into the civil service, and especially not as a scientist. So she was a total rock star. And she is the woman who basically got Americans to trust refrigeration wouldn't kill them.
A
And it doesn't seem like it kills anybody.
B
It doesn't. But does it do them a lot of good? This is the question I sort of tackled when I looked at, you know, has refrigeration been good for our health? And it's a harder question to answer than you would think. People straight off the bat are like, of course now we can have fruits in winter, how can it be bad for us? Well, it turns out that, for example, those fruits are much lower in nutrients, vitamins and minerals and phytonutrients than they were in our grandparents day, in part because of the breeding for shelf life to be able to be refrigerated. So there's that. There's also the fact that we can buy a lot of fruit and vegetables, but we don't necessarily eat them. There's also the fact that, you know, when refrigeration was introduced, everyone was like, oh, this is terrific, we can eat more red meat and be strong. Well, our ideas of what is healthy to eat have changed. Another thing that is increasingly emerging is that our gut microbes, the little microbes that live in our gut and outnumber us by trillions to one. They have a huge impact on everything from our health and our immune system to our mental health. And they are profoundly altered by refrigeration because prior to refrigeration we consumed much more fermented food. So, and fermented food full of beneficial microbes that our gut microbes like that end up having a huge effect on our health. So yeah, pros and cons, on the other hand, salt consumption reduced when refrigeration was introduced. And that's been a huge benefit for public health. So it's a harder question to answer than you think.
A
Well, one of the things, one of my pet peeves is, you know, food waste, I hate that so much food gets wasted. And so you would think, well, refrigeration prevents that. But I've always thought that people buy more food than they probably should because they think it'll stay in the refrigerator and then it sits in the back and goes bad and then it gets thrown away anyway.
B
You've totally nailed it. That is exactly it. So one of the reasons people thought refrigeration would be a great blessing at first is because so much food was lost getting from farms into the city to feed people. A third of all food was, was thrown away. And people thought this was just an unbearable waste. And it was. Refrigeration did stop that. The problem is that we now throw away a third of the food we buy. So that waste is just sort of transferred where it Happens. It doesn't happen on the way to us. It happens once we bought it and we just let it pile up in our oversized fridges. In the fridge, it's like a, I mean, food waste. Researchers described it to me as a clean, cold waste waste bin. Because you put stuff in there, it seems like it's going to be good. Then your plans change and you think, well, it's in the fridge, it's fine, I'll have it tomorrow. Oh wait, now it's the end of the week. Now it's the end of the next week, it's gone bad, I'll throw it away. People don't even know what's in their fridge. Your crisper drawer gets so full that you can't see what's in there. People also don't know what freshness is anymore and they have to look at a sell by date rather than trusting their nose or giving it a quick squeeze. And so that also contributes to waste because they'll throw things out that are perfectly good. So a lot of. And those are all directly connected to, to refrigeration and to the size of us refrigerators and this sort of artificial abundance mindset that they encourage.
A
So what did people do? Because there is some food like milk, butter, things that seemingly. Well, no, butter doesn't have to be refrigerated. People just do. We don't actually put our butter in the. I mean, we always have some out because it doesn't have to be refrigerated.
B
Yeah, and you can spread it that way.
A
Right, right, exactly. But milk does. Or I mean, it'll go bad faster if it doesn't. It'll go bad pretty fast if it's not in the refrigerator. So what did people do before that?
B
They made buttermilk, they made yogurt, they turned their perishable products into non perishable ones. It just so happened that those were different. They had benefits. I mean, I love, There's a famous quote, cheese is milk's bid for immortality. I mean, cheese is a great thing. I personally think cheese is a bit of an improvement on milk. So many of humanity's most delicious foods come out of trying to turn something that's very perishable into something that has a little more legs on it.
A
You know, I hadn't really thought about this, but if you look at pictures of older refrigerators, like from the 40s and 50s, even the 60s, they were a lot smaller. And today we have these big refrigerators and when you have a big fridge, you feel compelled to fill it up and you fill it up with food. You can't possibly eat all of it before it goes bad.
B
US refrigerators are the largest in the world by far and away. You know, they're the nearest equivalent even in Europe, or two thirds the size. And most of the world is dealing with something half the size. And that's before you get to the huge percentage of American households that actually have a second fridge in their garage or even a third. There's a lot of fridge space to be filled and no one wants an empty fridge that feels like you don't have enough. So anxiety provoking. But yeah, you're absolutely right. And I think, you know, fridge designers have tried to solve this. They've tried to give us smart fridges that will tell us what's in there. Really, we would waste a lot less if we had smaller fridges and shopped more frequently in, you know, walkable cities. That's possible, but we haven't chosen that route.
A
Are there any advances in or on the drawing boards that or is. You just make it cold, you take your box and you make it cold. And that's the beginning and end of refrigeration.
B
I love this question. Preserving food is one of the primary concerns if you're a human. It's up there with, you know, reproduction and surviving, you know, attacks from other animals. This is a, you know, keeping food good so that you can continue to eat it is one of our primary evolutionary drives. And yet when refrigeration was introduced, most people thought it wasn't going to be the winning solution. There were a lot of people who thought maybe, you know, some kind of coatings or fumigation or. There were, there were a whole range of technologies being developed in the 1700s that looked more promising than refrigeration. And frankly, that research is now happening. As we understand the downsides of refrigeration, especially in terms of climate, people are picking that back up. And, you know, you want your beer cold, you want your ice cream frozen, but your produce doesn't actually need to be cold. It just needs to be fresh. So if you can achieve that with a coating, which company in Santa Barbara is working on, they have a coating that will keep food produce as fresh just with that coating at room temperature, as refrigeration would do, you can get four weeks with a bell pepper sitting on the countertop at room temperature using their, their coating, which is entirely made out of food molecules. Now people are working on that. It might be that we don't need refrigeration. For all of our food, we'll still want a cold beer, but maybe our produce doesn't have to be refrigerated and that would be incredible.
A
Well, it's really. This whole story is really interesting in a couple of ways. One, that it is so new that refrigeration is only 150 years old. And secondly, it affects our lives in so many ways and yet it's still somewhat invisible. We don't think about it much, but man, imagine life without refrigeration. I've been talking to Nicola Twilley. She is a writer, frequent contributor to the New Yorker, and author of the book How Refrigeration Changed Our Food, Our Planet and Ourselves. And there's a link to that book in the show notes. Thank you for coming on today, Nicola.
B
Thanks, Mike. It's been great.
C
So good, so good, so good.
B
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It's poetry in motion. Like you, I imagine. I know what a volcano is. I've seen them on TV and in the movies. I know that smoke and lava comes out when they erupt. And that's about all I know. And yet, according to people who do know more, volcanoes are fascinating. They're all over the world and we should probably know a little more about them. Here to reveal the amazing world of volcanoes is Tamson Mather. She is a professor of earth sciences at the University of Oxford and author of the book Adventures in what Volcanoes Tell Us about the World and Ourselves. Hi, Tamson. Welcome to something you should know.
C
Hi. It's great to be here.
A
So first, I guess we need to understand what a volcano is. So what is a volcano?
C
So volcanoes are places on our planet where molten rock that we call magma when it's inside the planet and lava when it gets to the surface. Comes to the surface. And volcanoes are the structures, structures that are built. So we often refer to volcanoes. They look like mountains, but they can actually also be big depressions in the ground as well. So think about big craters or big calderas like Yellowstone or Santorini in Greece.
A
So my image of a volcano, and I think for most people is it's a mountain. It's a mountain with smoke and lava coming out, like Mount St. Helens. Do volcanoes create that mountain? Or do volcanoes use a mountain that already exists to erupt? Which is the chicken and which is the egg?
C
Yes. So in the case of Mount St. Helens, it's what we call a strata volcano. It's been made up of layers of lava and ash and other volcanic products that have been erupted. So, yes, in the case of Mount St. Helens and many other volcanoes, the mountains have been built by the volcanic activity.
A
What causes a volcano to. Basically, at some point, they all stop doing what they're doing. Why do they stop?
C
That's an excellent question. It's not something we fully understand. So in some cases we do have a really good understanding. So Hawaii, for example, is fed by a hot spot underneath the volcanoes. So again, it's down in the Earth's mantle. And as the rigid Pacific plate rides over that hot spot, it actually takes the volcanoes away from that source of magma. So Kilauea and Mauna Loa are the active volcanoes at the moment. But as you go over to the west along the Hawaiian chain, the volcanoes become extinct. And that's because they've actually moved away from the source of the molten rock that fed them.
A
Ever since I was a child, my theory or my understanding of what volcanoes are, and I think a lot of people grow up thinking this is that, you know, somewhere in the center of the Earth is this fire, that the Earth has got fire in the middle of it, and the volcano is that fire. Coming up. How accurate is my childhood theory?
C
Well, that turns out not to be quite correct, but. But actually, in a funny way, it's where we started as where the science started. So hundreds of years ago, people thought basically that's what volcanoes were. They thought that that was where Earth's internal fires found their way to the surface. Very much like your, your idea there. People had these ideas of the bigs of chimneys for Earth, earths in a fire. And then even when Christianity took a hold, people thought of them as being gateways to hell even. There's incredible stories of the conquestadors erecting crosses over Masaya volcano in Nicaragua to guard the escape of evil Spirits from its mouth. But since the modern era of science, we've been able to understand much more about our planet's internal structure. And using seismic waves, which are basically the vibrations that we feel coming through the Earth when there are big earthquakes, for example, we can record those and we can learn a lot more about the internal structure of the Earth. And what we find is that most of the Earth is solid. Rather than having any pockets of melt that stay there all the time, the very inside of the Earth there's a liquid outer core, but the mantle, which is the bulk of the Earth, this is about 65% of Earth's mass, is actually most of the time solid. And it's only in these very special circumstances where it melts and you get magmas generated that feed volcanoes.
A
So my theory at least I share my theory with a lot of other people at least centuries ago, they believe what I believe.
C
Yes, absolutely. You're doing well. Just a few centuries out of date.
A
That's okay. And then, so we, then we move to science class. And I remember in science class that for there to be fire, you need oxygen. If this is going on underneath the surface of the Earth where there is no oxygen, how can there be fire?
C
Exactly. So this is not far in the same way as, as a bonfire or a fire that we might have in, you know, the, in the great at Christmas time or something like that. This, nothing is burning with volcanic heat. The rock is, is red hot when it comes up to the surface. So many of the things that we refer to as, as fire in a volcanic sense actually aren't far at all. Nothing is burning. There's nothing you can put out. Things just cool down. So it's a, it's a very different type of process.
A
How good is science at predicting volcano eruptions?
C
We're getting better and better, but it's still really, really challenging. So we have lots of well monitored volcanoes. You get a lot of really useful data. So seismic data, which is the very small tremors and very small earthquakes that you get when magma or gas move in the Earth's crust, gives us lots of really useful information. And then the changing shape of volcanoes is also really important for us. So just an example, in 1980, before the MA Mount St. Helens eruption, it kind of blistered up like a boil on the side of the volcano and then there was a small earthquake. And it was from that swelling that the eruption initiated. So we can pull all these different strands together in order to make a prediction that a volcano is very likely to erupt. But it's only generally a forecast. It's a bit like weather, we can't be sure. And the other challenge that we have is that we might be able to say it looks like it's going to erupt in the next month. But actually saying it's going to erupt in two days time, which is a really helpful piece of information if you want to evacuate a big city, is much more difficult to do.
A
And when you, even when you do predict that a volcano is going to erupt, can you predict with any kind of certainty how much it's going to erupt, how big an eruption it's going to be?
C
That's another big challenge. And often we go back and study its past behavior in order to try and understand its future behavior. And sometimes we can use things like how much it's deformed, how much it's swollen up to give us some clues about how much magma has arrived in the system.
A
Are volcanoes monitored like actively? Are there people over there going, let's keep our eye on this one every day?
C
Well, in some places, yes. So the USGS do a great job monitoring the US Volcanoes. They have a lot of resources and a lot of expertise people monitoring that. In some parts of the world where there are fewer resources, volcanoes are not as well monitored. And in some places they're very remote from populations. So again, maybe it's a little less important to keep them well monitored at all. But a really powerful tool we have now actually are satellites. So we can use satellite remote sensing, basically satellites that send radar beams down to the, the surface to map the shape of the surface. We can actually use these types of satellite to monitor volcanoes globally without needing there to be infrastructure on the ground.
A
Have you ever seen one?
C
An erupting volcano? Yeah, yes, absolutely. It's, it's one of the, well, I think one of the most astonishing, awe striking things that you can experience as
A
a human and maybe a little frightening a little bit.
C
I think, I think it's important that one is a little bit frightened. I mean these are enormously powerful forces and, and they need the, you need to show them due respect.
A
Yeah, I guess it depends on how far away you are as you're observing it as the house and the type
C
of, the type of eruption as well.
A
And so when a volcano erupts and when I imagine the images of Mount St. Helens and you know, it all, in addition to the lava, which is very dramatic, there's also a huge amount of smoke or whatever that is. And how dangerous is that? Is that A real concern,
C
yes. So the gases that come out are a cocktail of different components. So there's a lot of steam in the gases, a lot of. A lot of water, and that doesn't tend to cause so many problems. There's a lot of water vapor in our atmosphere anyway. We see it every day as clouds. But there's also a lot of sulfur dioxide, which is a acidic gas, and other acidic gases like hydrogen chloride and hydrogen fluoride. So in the local facility, in places like Hawaii, where you have gas coming out of these volcanoes all the time, you can get quite substantial drops in air quality and acid rain problems, damage to vegetation.
A
Can volcanoes ever be so big and the eruption so big that they alter the climate in some way, that they change something, or is it a ticket? Dramatic, yes, but it's temporary and things eventually go back to normal.
C
Well, this is a, this is a really fascinating question. So volcanoes actually alter our climate and environment in huge number of different ways. But just to give you an example, if we have a really big eruption which punches up material up into the upper atmosphere, so the layer of the atmosphere known as the stratosphere, which you might know about because it's where the ozone layer is, which is obviously very important to our existence, if it punches up into that layer, basically the sulfur dioxide can oxidize to form a haze, a kind of veil of aerosol that can make the atmosphere really hazy high up, and that can reflect some of the sunlight back off into space and actually cool the planet lower down. So a really good example of this was in 1815, there was an enormous eruption of Mount Tembora in Indonesia. And this altered global climate patterns really profoundly. So the year 1816 was known in Europe and North America as the year without a summer. We had things like snow in New England in June, we had crop failures, we had famine. In various parts of the world, people were forced to eat their, their cats. Rather tragically. In Switzerland, there were riots In France, there was a great push of migration from, from New England to the western states in the U.S. and that was all caused by the volcano changing the global weather patterns.
A
Wow. I never knew that. That's fascinating. That I never heard that before. That, that's, that's pretty big. That's big news.
C
Yes. One of the really interesting things was at the time, people didn't connect these phenomenon up subsequently, that we've really learned this, right?
A
Yeah. I would imagine the science wouldn't have been available to say, well, the reason for that is this. And this is why it's happening. And people must have been very confused and wondered, well, what's going on? You know, the end of the Earth? Yes, totally. Yeah.
C
Yeah. So really, the eruption that people really became aware of was in 1883, which is the Krakatau eruption again in Indonesia. This did not have such a profound effect on global climate, but because we had the undersea telegraph cables in place, news could travel around our planet much more quickly. So people were aware of this eruption within hours of it happening and started looking for phenomenon, looking for changes, so looking for amazing sunsets which they saw and evidence of the pressure wave traveling around the planet in terms of barometers and things like that. So actually, it was the communications technology at the time really changed the way that we experience and understand, understand volcanoes.
A
Once a volcano has erupted, is there always the potential that it can erupt again? Or are you able to identify some volcanoes, these are dead and we'll never hear from them again.
C
So some volcanoes, the tectonic plates have rearranged themselves as they've been moved away from the source of their magma. Other volcanoes do seem to have gone. Gone dead just because they haven't erupted for a very long time. And often we can't exactly work out why. It's just that the focus of the way that the magma finds its way to the surface seems to have shifted. So we can definitely make again, a very good forecast, a very good prediction that that volcano is unlikely to erupt again. But these are unpredictable mountains, so they often have the last word and sometimes they still can take people by surprise.
A
Is there any sense of the last volcano that erupted for the first time? Like this was the first time this mountain spewed out that stuff? Or do most volcanoes that we see for the last, I don't know, couple hundred years, they've erupted before?
C
Oh, there's plenty of examples of new volcanoes. So in some ways, the activity that's going on in Iceland at the moment, on the Reykjanes Peninsula, these are new fissures that are opening up all the time. We don't really have a central volcano there. These are more like fissures that open up and spew forth lava flows. But another famous example is the Parakutin volcano, which basically sprung up one otherwise normal day in a farmer's field in Mexico.
A
Do volcanoes ever erupt, or does volcanic activity ever occur in places where it wasn't expected? Or do you pretty much know where it's going to happen, generally speaking?
C
Generally, they come up in places that we expect volcanism so in areas that have had other volcanoes going off in the past or other similar types of fissure eruptions in the past, they don't normally come up and they don't normally come up in completely unexpected zones away from other volcanic activity.
A
When lava flows out of a volcano, how hot is it? How hot can it get?
C
So the basaltic lavas that come out of volcanoes, like Kilauea in Hawaii or the volcanism on Iceland, are getting on for about 1,800 degrees Fahrenheit.
A
Is there anything about volcanoes that you've seen in the research that would surprise people?
C
One of the things that fascinates me about volcanoes is we would not be here, I don't think as a species if it was not for volcanoes.
A
How so?
C
Although we think of volcanoes probably most often as forces for destruction, they've also been really important forces in terms of building our planet's continents, which we're obviously land based mammals. So really important. The gases coming out of volcanoes help to maintain our atmosphere over geological time. So they've kept us within certain bounds of temperature by our atmosphere helping for that and protected us. The atmosphere protects us from lots of external forces. And then there's even some thinking that volcanic lightning or the hot vents on the ocean floor might have been some of the first places that the molecules for life were put together that laid the foundation for all of life on this planet. And I think that's incredible.
A
Well, that puts the subject in perspective that we might not be here if it weren't for volcanoes. I've been speaking with Tamsin Mather. She's a professor of Earth sciences at the University of Oxford. And the name of her book is Adventures in Volcano Land. What Volcanoes Tell Us about the World and Ourselves. And there's a link to that book in the show notes. Thanks, Tamsen. What a great topic. Thank you.
C
Thanks, Mike. It's been really fun.
A
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Episode: How Your Refrigerator Changed Human History & The Surprising Purpose of Volcanoes
Host: Mike Carruthers
Guests: Nicola Twilley (on refrigeration); Tamsin Mather (on volcanoes)
Airdate: June 20, 2026
This engaging episode of Something You Should Know delves into two deceptively everyday topics that have profoundly impacted human civilization: refrigeration and volcanoes. Host Mike Carruthers interviews Nicola Twilley, author and journalist, about how refrigeration transformed our food systems, health, and habits. In the second half, volcanic expert and Oxford professor Tamsin Mather explores the science, myths, and world-altering effects of volcanoes, revealing why they are central to life on Earth.
Guest: Nicola Twilley, author of Frostbite: How Refrigeration Changed Our Food, Our Planet, and Ourselves
Segment Timestamps: [05:22 – 28:50]
Guest: Tamsin Mather, Professor of Earth Sciences, University of Oxford
Segment Timestamps: [30:34 – 48:00]
This episode reveals how two of the world’s most commonplace phenomena—refrigeration and volcanoes—are anything but ordinary. Refrigeration made artificial cold an essential part of modern life, creating enormous changes in food availability, nutrition, and even waste, but not without controversy and unintended effects. Volcanoes, meanwhile, are both destructive and life-sustaining, shaping continents, Earth's atmosphere, and possibly even the origins of life itself. Together, these two explorations remind listeners how technological progress and planetary processes silently shape humanity’s daily existence and survival.
Further Reading
This summary captures the episode’s core insights, notable moments, and the voices of the experts for listeners who want the depth without the runtime.