Malthusian Swerve

0:19Hey, this is Radiolab. I'm Latif Nasser. So a couple of weeks ago we put up a brand new episode called growth. We talked about pumpkins and a finger and some slugs and every single person on our planet. But there was one growthy, you know, currently growing thing we did not talk about, which is the economy. Now, what got me thinking about economic growth was not all the stuff that's in the news, the tariffs, the fear of the recession, all that stuff that everybody's talking about. What started it was a lecture I heard a little while back by, of all people, an astrophysicist. So I'm going to sketch what we know about Earth's history, cosmically speaking.

1:07Her name is Sandra Faber. She goes by Sandy. Brilliant scientist. She co-authored the standard model for thinking about how galaxies form. She won a National Medal of Science back in 2011. and she started the lecture by saying, we have a pretty happy little planet to live on. Earth is a good place to live for, let's say of order, 100 million years at least. Should be livable for a really, really long time. Okay. Except, she goes on to say, for us. Over the last century or so, we've been seeing planet-wide GDP growing exponentially. So what she did is she took the average gross domestic product worldwide, and that's a rough measure of economic growth, and that had been growing recently around 3%, which for economists is like a happy little growth number.

2:01So you will recognize 1.03, 3 % as the... But Sandra took that 3 % and with some quick math, she started to just play it out year after year. And in her lecture, she's showing this chart where you can see this curve just shooting up. We can see this number is completely ridiculous. And she was basically like, look at all that growth. That's eating up Earth's resources. A large number here is bad because it means that we want more of that product. And so even though Earth should be good for 100 million years, we're going to just eat the planet up. We're going to devour the physical, material level of this planet.

2:46We're going to eat it up in more like a couple thousand years. And my concern is that we're not talking about this.

3:02And when I heard that, that was, that was, that was breathtaking and horrifying. And honestly, like, I haven't been able to stop thinking about that number, 3%. It sounds like a specific thing, but also it's, it's kind of abstract and mathy. And I wanted help. I wanted help to parse this out. Like, how bad is that really? How bad could that possibly be? And so I turned to someone whose job it is to literally make sense of this exact kind of thing. Hello. Hi, how are you doing? Hi, I'm doing well. How are you? And we had what I felt like was a kind of a roller coaster of a conversation. So I'm just going to play it for you right now.

3:49Yeah. Okay. So I am Jeff Guo. I'm one of the hosts of the Planet Money podcast at NPR. Terrific show. Thank you. um and uh i i guess what do i do i talk about economics all day that's oh my god that's what i'm i need you i need you to help me it's more than scratch and itch i need you to help me cure this existential dread that you have now that's exactly right yeah yeah okay um well i mean i guess where i would start is and you know i would hate to contradict a nobel prize winning astrophysicist uh yeah sounds like you know starting out on dangerous territory there i mean what she won the national medal of science not the nobel but she's gonna she's gonna it sounds like she's gonna okay yeah sure fair um but you did ask me to kind of look into what things are we gonna run out of yes yes yes oh my gosh i'm so excited okay yeah yeah so um so i did so i looked at a bunch of things that people are kind of worried about.

4:53Great. And I just did some very rough back of the envelope math. Like this is so totally not precise. My favorite kind of math. My favorite kind of math. It's so hand wavy. Great. I love it. Okay. So I don't know what should we start with. Copper? Yeah, that's a big one. Copper's a big deal, right? Very big deal. So if you look at copper consumption over the past century, since the Industrial Revolution, Okay. You know, our demand for copper has grown about 3 % every year. Okay. Like, you know, in recent years, we've consumed about 26, 27 million tons a year of copper. Yeah, yeah. So if you just, you know, extrapolate that out, if you just assume copper is going to keep growing at 3 % every single year, right?

5:39Fair. Fair assumption. I looked up how much copper people think we have. According to geologists, what we know is out there and could theoretically get to. and that number right now is 5 to 6 billion tons. Okay. It's not nothing, but we're using it pretty quickly. And if you just assume that this number is going to keep growing at 3 % a year, it would take about maybe another 70 years and then no more copper. That's it? 70 years? 70 years. Okay, so that sounds terrible. It's true. It's true. That's assuming, of course, that we do keep consuming copper that quickly. Using copper and needing copper the same way that we are.

6:17Yeah, yeah, sure. T minus 70. Yeah. No copper. No copper. For anybody. No copper. Okay. Okay. So then what, but then, so that's, this seems to point exactly to Sandy Faber's point, right? It's true. It's true. It's true. Yeah. Do you want to do another one? Oh, that's the end of it? I thought you were going to be like, but there's like a giant, there's a copper thing that we're going to, no, there's no, but that's it. It's just like, yeah, she's right about copper. Okay. But there's a, but there is a, but coming up. There's a, but. Yeah. Okay. Okay. Okay. Okay. You want to go through more of them before we get to the butt?

6:47Is that the idea? Yeah. Okay, okay, okay, okay, okay. Next one. Okay, next one. Okay, so another one I looked into is sand. Okay, yeah. Sand is exactly... Which seems like there should be a ton of that. Seems like there should be so much of it. Yeah. And you know the reason why we need sand, right? Why do we need sand? For concrete. Ah. So it's actually so important that we don't know how much we're using. Oh, my God. Like we're using so much. We just, we actually don't know. But like ballpark estimates, we're using maybe 50 billion tons of sand and gravel every year. Okay. That sounds like a lot.

7:24I don't even know. I can't even visualize that. I don't know. It's a lot. Right. And I couldn't even find how much sand and gravel there is in the world. Like nobody actually knows. Okay. This is one of those numbers where it's like, oh. But we're doing like back of the envelope math here, right? Right. Right. So I was like, well, if we don't know how much sand and gravel there is in the world, surely we know how much rock there is in the world, right? Totally. Totally. Totally. So I looked it up, and according to geologists, the Earth's crust, all of the Earth's crust, contains maybe like 23 quintillion tons of rock and stuff.

8:04Okay. Okay. But it does seem like the whole point of sand is that it's like teeny tiny. It would take a lot of energy to turn that rock into sand. It would. But assuming that we're able to do that, right? Okay, okay, great. Assuming that we're going to use sand and gravel at a rate that grows by 3 % every year, year after year after year, it would take about— Do you want to guess how long it would take to deplete the entire Earth's crust? Wait, so a quintillion based on the growth rate and the uses now. I would imagine this one is going to be – this one is not on Sandra Faber's side. I'm going to guess this one is like way, way, way far from now.

8:46Like this is going to be like a million years or something. Five to 600 years. That seems so short again. It does, doesn't it? That is way shorter for the whole crust. I know. Oh, my God. That's not – like it's long, but it's not that long. Like that's like – that is nuts. All right. I got a couple more. This is just making me more and more existentially worried. Okay, but keep going. That's how I felt when I started on this journey, right? I got a couple more. Okay, great. Love it. I got to pull up my spreadsheet. I'm going to talk about lithium. Okay, great. Good one. Good one. And lithium, you imagine there are like those giant deserts filled with those like sand flats or whatever, right?

9:30Yeah, in Bolivia. In Bolivia. Yeah, Yeah. Yeah. Okay. So this one will be again, like I think this one, I feel like there's going to be a curveball in here where you're like, no, no, no. We haven't found it up for, you know, for millions of years. Anyway. Okay. Keep going. Okay. Hang on. Let me see. Let me pull up my, where did my notes go on this? I can't wait when we have to fact check all of this.

9:55Okay. Lithium. So we are using about 190, 200 ,000 tons of lithium every year. Right. That's kind of... Okay, so that's like in phones, electric cars, da-da-da-da. Yeah, batteries. Batteries is a big one for lithium. Very important. Lithium consumption, of course, has been exploding. So over the past decade, lithium has been growing. Do you want to guess how much it's been growing? What, like 5 % or 10 %? On average, around 20%. Okay, wow. So we need a lot more lithium. Which is good, which is good, which means like more electric cars, more recyclable batteries and stuff. That's great. Yeah. So geologists think that of all the lithium that we know is out there, there's probably like 105 million tons of it.

10:45That sounds a lot less than the sand. Like this doesn't sound, this is going to get worrying. Okay, keep going. Right. And so, you know, if you do this whole, you know, the same math and you just if you assume if you just assume just, you know, for the sake of argument, it's only going to grow at 3 % a year. Right. Yeah, sure. We'd probably run out of lithium around about March. I feel like you're going to say like I feel like you're going to say like so soon. Tomorrow. About about 100 years. OK, 100 years again. It's not bad. No, it's it is bad. It's bad, Jeff. It's bad. We need that. Like, we're going to need that later for even better stuff.

11:27It's true. Okay, keep going. I'll do one more. I'll do one more, which is, this is a big one, oil. Really scary one. Yeah. But hopefully we're weaning off of this one. So maybe this one is a different. Hopefully. Like it's going in the opposite direction. Hopefully. Doesn't seem like it's really happening yet. Oh, God. But. But. I don't think you have had a single piece of good news here. Just wait for it. Okay, all right. So if you look at oil, right, how much do we consume every year? About 37 billion barrels of oil as a world. How much is left? Probably 1.6 trillion barrels. Really? Yeah. So it's not.

12:07That's a lot. It's a lot, but it's maybe less. It's less than I thought. So another way to say 1.6 trillion is 1 ,600 billion. Right, right. So 37 billion a year. We have about 1 ,600 billion barrels left out there. Yeah, when you say it like that, it sounds quite alarming. Not great. So, you know, if you do the math again, exponential growth, very scary. But we do want to use less of it anyway. Right, yeah. I'm ambivalent about this. Trying to. Yeah, yeah, yeah. Okay. About 28 years. No way. Yes. That is nothing. 2052 might be the day we run out of oil. Wow. Maybe. Maybe. I was worried about when Sandra Faber said we had thousands of years and you're like, you're taking me even an order of magnitude less.

12:56Yeah, maybe decades. Yeah. So I started to get, you know, a little nervous. And so I thought, well, like what happened in the past? You know, like when we were overexploiting some resource and it looked like it was going to run out. And when I looked into it, there's this funny thing that happens. and so just for example let me tell you a story um please it's about medieval england okay so it's the 1400s okay it's like medieval england it's the 1400s and this amazing new technology has just arrived on the shores of ye olde england and it is this new way of making iron okay it's called the blast furnace just so just like very briefly like before the blast furnace you kind of had these backyard ovens, basically, where you kind of baked the iron ore to make the iron, and they were, like, super inefficient and really slow and not great.

13:54Okay. But this blast furnace, the scientific innovation was that if you blew air onto the fire, you could get it really hot, and then you could get it so hot that you could just melt the iron, and it was amazing. Got it. And this, like, revolutionized iron making. So these blast furnaces, they're these huge 20-foot-tall stone towers. You would have these giant bellows at the bottom blowing in air. I was just imagining the bellows. I was just imagining the bellows. Okay, cool. Okay. So that's the key innovation here. Yes. And medieval England, iron was so precious, so important. You needed it for plows and spades, horseshoes, pots, kettles, nails, hammers.

14:35Yeah, whatever. And so now you had this technology that you could make. These blast furnaces, they could make a ton of iron a day. A ton, a literal ton. A literal ton, which is like just unprecedented. The problem with all of this is what was the fuel that went into this blast furnace? And at the time, it was charcoal. Which is charcoal is made out of wood, is that right? No. Yes. Yes. So this was not as good. So they're like slurping down forests, basically. Yes. Yes. Just picture the English countryside, right? You've got these blast furnaces sending up these huge plumes of smoke. And then everyone's just chopping down trees as fast as they can to feed these giant blast furnaces.

15:16And it makes people really concerned. Yeah. Like really concerned. They're like, oh, my God, where are the trees going? But it got so bad that by the late 1500s, you have parliament banning new iron mills from starting up in different places. They're like, we cannot do this. We just cannot deal with this. Because we have one tree left and everyone's about to cut it down. We got to save the trees. The tree. Yeah. Yeah. Yeah, you even have Queen Elizabeth I, not the second, the first. Okay, all right. You have Queen Elizabeth I. She is issuing royal edicts saying, no more charcoal making in my royal forests.

15:55Wow. We just can't do this anymore. But then something happened. Okay. So in 1709, this English guy named Abraham Darby, he figured out how to use a different kind of fuel. Okay. So not charcoal. So maybe you want to guess what he figured out. Oil, probably, right? Coal. He figured out coal, yes. He figured out you can use this sort of modified coal to run these blast furnaces. And this changed everything. I'm not exaggerating. The iron industry took off. This led to the Industrial Revolution. We avoided the problem. We avoided the shortage. And it's not an isolated example. This is a pattern that comes up.

16:40We did this with whales. When we stopped using whale oil for lamps and started using kerosene, we did this with rubber. We started making synthetic rubber instead of getting all our rubber from trees. It's happened over and over again. We have stood at the edge of the cliff where it looked like, oh, crap, if we keep doing what we're doing, we are going to run out of some precious resource. And then somehow, at the last minute, catastrophe is averted. I mean, this has happened so often. I feel like we should give it a name. I know. I was going to say, do economists have some kind of wonky name for this?

17:19Not that I could find, so I'm going to take the opportunity to give this a name. Jeff, it is yours. Yours to name. Please. I think we should call this the Malthusian Swerve. Swerve. Malthusian Swerve. Mm-hmm. Okay. And why that? Because remember, do you remember Thomas Malthus? Yeah. Yeah. And if I remember, his whole thing was like, you know, you tell me what his whole thing was like. Yeah. So he was this famous English philosopher type. He lived, you know, he grew up in the 1700s, pretty much around the time that coal was taken over England. Yeah, yeah, yeah, yeah. Right. So he was seeing a lot of this happen.

18:01And he's famous for predicting that humanity's growth would hit a limit, that populations would grow faster than we could provide food for them, right? And so the future of humanity was to be limited and trapped by our own lack of resources and that everybody would just be miserable and sad and poor and hungry forever. He does not sound like he would have been fun at parties. Yeah, yeah, he's a real bummer. But maybe what he's more famous for is that none of that happened. The reason that Malthus's prophecy didn't come true is due to what I would say is the most important Malthusian swerve of all time.

18:43Okay. And this one is fertilizer. Right. Right? It was like the Green Revolution or whatever, right? Is that right? The fertilizer revolution. Yeah, yeah, yeah. Yeah. So I don't know if you want to hear the guano story. Please. I love the guano story. We can do it quickly. I know the guano story, but I love the guano story. And I want to hear you tell the guano story. Okay, let's do it together then. Yeah. Okay, let's do it together. So this is like the 1800s, a little bit after Malthus' time. In the 1800s, Europeans are starting to realize you can really supercharge food production if you use better fertilizer.

19:17Yeah. Right? And specifically, there's this one fertilizer that indigenous people in South America were using that was amazing. Guano. Guano. Which is basically just bird poop. Yeah. Right. Okay, so basically you would have all these seabirds and they would poop on these rocky islands and coastlines along South America. And the poop would just accumulate. So the Europeans, so like in the 1800s, the Europeans are importing hundreds and thousands of tons. They're literally fighting wars over control of these guano islands. Like Spain is getting into wars with Peru and Chile. Yeah. Like, just who gets to seize the poop islands?

19:56Right. But the problem is we were using guano way faster than the birds could, you know, make the guano. Yeah, yeah, yeah, yeah, yeah. And then in the 1900s, in the early 1900s, some German chemists figured out a way to basically make synthetic guano. They invented an industrial process to literally pull nitrate. Nitrogen. Yeah, that's like the key ingredient in guano. Right, right, right. pull it out of the air and make synthetic fertilizer. And that is on the order of like alchemy discovery. Like that is like this thing that is super abundant in the air all around us. It is literally the majority of the air, but it was unusable.

20:42And then there was a hack where we then figured out how to make it usable. That seems like, that's like a miraculous technological breakthrough. Yeah, it's a miraculous story. And it is like maybe one of the best examples of this thing that I'm going to call the Malthusian swerve. Swerve. I like it. I like it. And so the swerve is like, it's like when you say swerve, I'm picturing like it's like a car about to collide into a cliff and then right at the last second swerves out of the way. Yeah. And Malthus is driving the car thinking that, of course, we're going to hit the cliff. And then really it's like the passenger who then just like yanks the steering wheel.

21:25It's like, nope, not going to happen. Right at the last second we figured it out. Yeah. And if you look at human history, this is a pattern that happens over and over again.

21:38I find this somewhat of a relief. It is sort of encouraging. but it also seems like there's so much drama here. And there might be a time where we can't swerve in time. Like what happens if and when we can't swerve in time? And also I would argue sometimes the swerves, sometimes we swerve right into another cliff. So for example, the example you talked about from charcoal to coal, which is great for the trees, except after a while, it's also bad for the trees, right? Like it's like global rising temperatures lead to wildfires, lead to trees not able to grow where they once were able to grow. Like it's like we're - It's true, but we've bought ourselves more time.

22:36Fair. Right? We've bought ourselves more time. But then we just always use that time to step on the gas to the next thing, right? And then maybe when we do swerve, then we swerve into something worse, something that causes, you know, war or exploitation or just messes up the planet in a way that is unswervebackable from. I mean, yes, that is all totally right. It is a mess. But, you know, to help us unpack it, I think we should talk about a swerve that we are in the middle of right now.

23:13Actually, first, we're going to swerve to break, but only for a minute. Then we'll swerve back and step on the gas directly towards a currently oncoming cliff.

23:47Radio Lab Latif back with Jeff Guo from Planet Money telling us about a thing he has noticed called the Malthusian swerve, where we're about to run out of some resource, but at the last minute, some new resource or idea or innovation comes along and saves the day. And just before the break, Jeff had been telling us about how he'd been looking for examples of the swerve back in the past. And I was like, OK, but is there a more recent example? Is there like an example of a Malthusian swerve that that happened, you know, in the past couple of years? And there is one oil. Oh, we're in the middle of the Malthusian oil.

24:23We are. Yes. Remember. Do you remember like in the 80s and 90s, all of the talk about peak oil? Yeah. Do you remember? Yeah, yeah, yeah, yeah, yeah, yeah. No, and even before that, like I think in the 70s and stuff, like it's like we keep having this conversation over and over again, peak oil, peak oil, peak oil. Yeah, exactly. Yeah. You have people, you have geologists, distinguished geologists saying, warning us that, you know, we're going to run out of oil, that we're going to reach peak oil very soon and that oil is going to diminish. Well, you just said it in 52 years or whatever. Like you just said it.

25:00Yeah, yeah. The same thing, yeah. Yeah. Well, back in the 1990s, they were saying it's going to happen in the 2000s. They were saying, oh, crap, like we're going to start running out in the year like 2000 something. Yeah. And if you look at oil production, like, yeah, it does, especially in the U.S. Yeah, it does kind of start to slow down in the 2000s. A lot of people were wondering about what are we going to do, how are we going to adapt, how are we going to move away from oil? And if you look at the chart, you'll see the oil production. It kind of starts to dip in the 2000s and then starts to rise again more and more and more.

25:34There's a swerve. And that was caused by the fracking revolution. But is that a swerve? Like, I mean, now we just found another way to get more fossil fuels. Like, is that even really a—that feels like we swerved and swerved right back in the same direction. That is one way to think about it. The way I think about it is, like, it's a mini swerve, you know? Like, oh, crap, we're running into the cliff. We can't find any alternatives. But we did find a way to get a little bit more oil out of the ground in the meantime. But in a way, running out of oil isn't even necessarily the problem here. The problem is the thing it's doing for everything else.

26:10It's true. The problem with fossil fuels, it's not that we're going to run out of them. We have too much of them. It's too easy to go and find oil on the ground. It's too easy. We have a problem that's not a scarcity problem. It's an anti-scarcity problem, right? And then we burn them. And then there's these horrible side effects for the environment. And then the world's getting hotter and wildfires are popping up. It's a much harder sell, though. It's a much harder sell to tell people, we have too much of this thing that's going to hurt you, as opposed to we have not enough of this thing. So take care of it.

26:45Yes. That is the key thing here, I think. Like you look at how these Malthusian swerves, if we're going to call it that, how they happened. I love it. I love it. Keep doing it. How did they happen, right? And it was people who were motivated by the terror of we're going to crash into this giant problem in so many years and we need to figure out how we're going to. Necessity is the mother of invention kind of thing. Yeah, yeah. Desperation is the inventor's best friend. Yeah, yeah, right? And you look at how an economy works. And I'm not saying this is the ideal way to operate, but an economy works through incentives.