162. Will We Solve the Climate Problem?

27:15Plants tend to like it. Plants tend to grow. People tell climate scientists all the time that, oh, carbon dioxide is plant food. And yeah, it is. Plants like carbon dioxide. But it is really hard to take carbon dioxide out of the atmosphere when you're on fire. I probably shouldn't laugh at that, but that was funny. Well, it's true. We expect that in the future, there's no reason that the terrestrial biosphere, stuff that's growing on the planet, there's no reason to expect it's going to continue to remove half the carbon dioxide emissions from the atmosphere. So we have these two competing effects.

27:51We have the carbon dioxide fertilization effect, which is plants like carbon dioxide, it's plant food, but that is going to be limited by water availability. It's going to be limited by nitrogen availability, other nutrient availability. At the same time, we start seeing climate change effects on the earth. Places that used to have forests maybe cannot support forests anymore. The absolute nightmare scenario would be the Amazon rainforest becomes a savanna. And so we expect to see shifts in what grows where and how healthy stuff is. And as a result, we expect that as carbon dioxide emissions increase, we can no longer rely on the earth to remove a lot of those for us.

28:35We think that is going to be a destabilizing feedback as well. So that was a flaw. In my simple thought experiment, I was only thinking about the direct effects of just when we burn the stuff that we can burn, how much will go into the air. And it left out all these feedback effects. So you have made me less hopeful about the scenario in which we wantonly burn everything we can over time. Yeah, I think we shouldn't do that. Look, I think many people agree that we shouldn't do that. But I also think, realistically, there's a good chance that we will, just by virtue of human nature and by virtue of the difficulty of agreeing on things.

29:17I mean, let me give you a great example. As I was doing research to talk to you, I kind of had a view that no government is really going to be able to impose the costs on their citizens of really fighting climate change. And so there'll be a lot of talk, but nobody will really do it. But the fact is, much to my surprise, the European governments have really committed to fighting climate change, and they've done a good job. The last data I looked at, European emissions were down 37 % relative to their 1990 levels, even though their economic output had grown by 70 % over that same time period. That's really a sign of a set of folks who are willing to pay the costs to try to fight this.

30:00Even the U.S. is down 20 % from our peak emissions in 2007. And that's a start. And that might actually make you feel kind of optimistic about things. I would first quibble with the framing that addressing climate change is imposing costs on your citizenry because it might be expensive to transition your energy system, but it is even more expensive to deal with unmitigated climate change. We are not comparing the costs of mitigating climate change to the costs associated with a pre-industrial climate. We are comparing it to an Earth that is 3 degrees, 4 degrees, 5 degrees Celsius warmer. The Europeans have done an amazing thing in reducing their emissions.

30:48But over the exact same period, 1990 to the present, Chinese emissions have gone from 2.5 billion tons to 12.5 billion tons. So that increase must be at least five times greater than the magnitude of the reduction that's happened in Europe. And so the totally natural thing for an economist to think is, well, at some point, the Europeans are going to say, wait a second, we're paying money to do the right thing. And the Chinese just keep on going along business as usual. And at some point, they're going to say, look, the climate doesn't care where the carbon dioxide came from. It treats all carbon dioxide the same.

31:24And it just stinks to keep on paying the cost of doing reductions while other people free ride on what you're doing. Well, yes, and I think there's another major factor at play here. And again, this is not something that I am qualified to talk about, but that has never stopped me before, which is geopolitics. which is the fact that Europe does not want to be buying a bunch of gas from Russia anymore. That doesn't seem to be a sustainable pathway forward for reasons that aren't necessarily purely economic reasons. In China, we actually are starting to see Chinese emissions flatline. Last month, China installed 100 solar panels a second.

32:07The amount of renewable capacity that China is installing is absolutely mind-blowing. And part of that is just this stuff is cheap and it works. But part of it is that China is looking ahead to the future and saying, we want to be an electrostate. We want to be in charge of the supply chains for these materials. We want to be the world's leading manufacturer of solar panels. We want to really be leading in the research and development of this stuff. And other countries are seeing that and they're saying, we want to be part of the 21st century. We want to be part of this energy transition because being stuck using fossil fuels is going to be like doubling down on using whale oil.

32:52That's the technology of the past. We want to be leaders in the technology of the future. So I think that there are other considerations that come into it besides purely an idealized market model. So I hear what you're saying, but I still, in my heart, have this really negative view of human nature. And I do think the data have not been inconsistent with that. We've been worried about emissions for a long time, but year by year, global emissions have still been going up. And let me use that pessimism to go back to thinking about when Stephen W. and I first wrote about climate change, and that was in our second book called Super Freakonomics.

33:35We had the basic belief that humans weren't going to do the right thing. And as a consequence, one of the ways humanity might have to try to work our way out of this dilemma was to try to intentionally alter the Earth's environment to cool it down, a set of strategies that people call geoengineering. So let me ask you, were you aware of superfreakonomics when it came out? And if so, I have no doubt it made you really angry. Yeah, I think there were a lot of real cranky climate scientists after that came out. You have not historically been much of a fan of this concept of geoengineering. It's fair to say, right?

34:14No, my view is that it's like having your stomach pumped. You're going to be glad that's an option on the table if you really need it, but you should really stop eating poison in the first place. So in my mental model of geoengineering, there's two buckets. One is trying to cool down the planet by blocking the sun, and the other is trying to cool down the planet by hacking the carbon cycle, by taking carbon dioxide out of the atmosphere. And so in this particular context, which one of those or both are you talking about? I'm more taken with the solar radiation approaches to geoengineering. In the book, we talked about sulfur dioxide and how you could put that in the stratosphere.

34:56But my own personal favorite one was the ideas that John Latham had, building a bunch of solar-powered dinghies which would putter around in the ocean and spray up saltwater to seed the right kind of clouds. So on a scientific level, we know that solar radiation management, whether spraying stuff in the stratosphere or seeding clouds that block the sun, that would probably work if your definition of work is to lower the global average temperature. But nobody cares about the global average temperature. People care about the consequences that come along with the change in a climate. Putting a bunch of carbon dioxide in the atmosphere warms the entire atmospheric column, whereas blocking the sun basically prevents sun from reaching the surface.

35:45Those are different things, and they do not exactly cancel each other out. And so as a result, we know that we will see impacts on the global water cycle. We will see shifts in precipitation patterns. We will see droughts get worse in some places, rainfall increase in other places. So that's something that we know will happen. And then there's known unknowns. We don't know exactly how that will play out. And then there's unknown unknowns, the things that we haven't even thought to think about. But the thing that really freaks me out about geoengineering is that science can inform this problem, but I don't want to be involved in making these decisions.

36:26I don't think scientists should be the ones making these decisions because this is an experiment on the entire planet. And I want to acknowledge that right now we are currently doing an uncontrolled experiment on the entire planet. But I don't believe that, well, there definitely is not now, and I do not believe there will ever be a global governance structure that is capable of making the decision to deploy or not to deploy. Guess what you said. It seems totally crazy that there's no entity right now that is trying in a unified way to think about both the ethics of doing these things, but also in a pragmatic way saying, look, as an insurance policy, shouldn't we be building our knowledge so that we have more options when we need them?

37:19Yeah, and I'm strongly supportive of model-based geoengineering research. I think we should be doing these experiments in our climate models. I think we should understand what we know, what we don't know, what we really need to focus more research on. For example, I myself am thinking lately about what would happen to the carbon cycle if we do this, if we spray particles in the stratosphere, if we block the sun. That's going to give us less direct sunlight, but it's going to give us more diffuse sunlight. And plants tend to like direct sunlight, but also like more diffuse sunlight. What's that going to do?

37:55Are we going to be able to mitigate some of these temperature-induced effects on plants? When it comes to deploying trials in the real world, I think those need to be approached with incredible care. And I feel incredibly out of my depth when it comes to who needs to be in the room, who needs to be making these decisions. Should these decisions even be put forward? Should we even be asking these questions in the real world at all? So that's something that makes me feel completely unqualified to even have an opinion on. You're clearly not excited about geoengineering, but you do write in your book about one form of it that I think hasn't been talked about very much, which is rock weathering.

38:43Could you explain how that works and why you think of the various options that have been offered about geoengineering, that might be one of the better ones? This kind of falls under that second bucket of how do we take carbon dioxide out of the atmosphere? And there are a lot of methods that have been proposed to do this. So enhanced rock weathering is a way to try to speed up the slow carbon cycle. So there's two carbon cycles. There's a fast carbon cycle, which is carbons in the atmosphere. Plants take carbon out of the atmosphere through photosynthesis to make more of themselves. They die, they get eaten.

39:22Things that eat them die, they rot. Their carbon goes back into the atmosphere. So that is a carbon cycle that basically happens on the timescale of lives of living things in the biological world. And then there's a very slow, millions or hundreds of million years carbon cycle, where rocks get weathered by the small amount of natural carbonic acid that's in rain. and then they go down, they get washed to the bottom of the ocean, the carbon is locked away there, and eventually it's released back into the atmosphere by large-scale tectonic activity, volcanoes, basically. So you're saying that the carbonic acid, by eating away at the rock, it actually gets absorbed into the rock and then it falls to bound the ocean.

40:09Okay, gotcha. Exactly. And this process is painfully slow, just geological time scales. And so the thinking behind enhanced rock weathering is, well, what if we tried to speed it up? And the simplest way to speed that up is just to grind up the rocks so that you have more surface area of rock that can get weathered, that can react with the carbonic acid and rain. And there have been some papers that are arguing that this would have what we call co-benefits. If you spread rock dust, volcanic rock dust on a field in some regions, that could actually make the field more productive, that could raise agricultural yields.

40:51That sounds great, amazing, miracle cure, but there are no miracle cures here. There's nothing that is going to be the one weird trick that's going to solve climate change. Enhanced rock weathering might be a particularly useful tool in our incredibly large tool belt and we're going to need everything. Economists are all in favor of a carbon tax. You guys love that. It just seems like such an obvious thing to do because the price of oil and gas and coal should reflect the damage it does via climate change. And we have some estimates of how big that damage is. And it's actually pretty easy to implement because we only pull oil and gas and coal out of the ground in a very distinct set of places.

41:39And virtually every economist I know thinks it's a good idea. Politicians don't seem to warm up to it, but it also seems like climate scientists aren't very excited about the idea. If we can't even convince you that it's a good idea, we're not doing a very good job as economists of making the case for why this is a good idea. I think the reason that climate scientists are so suspicious of a carbon tax is that we know what we don't know. We physicists are fairly aware of the fact that we don't understand how people work. On paper, it sounds like a great solution. Just tax carbon, give a rebate back, or do something productive with all that money.

42:18Sounds great. But we know that climate change happens in the real world. It happens in the world that we make for it. So all of these rising temperatures and worse heat waves and more severe droughts, they are happening to a planet filled with humans and pre-existing human structures. They're happening on a planet that has a history. It has a geological history, but it also has a human history. It's not a blank slate. If you try to implement a carbon tax on this incredibly messy, disorganized, ornery earth full of humans who don't do what they're told and don't do what they're supposed to. You know, I don't necessarily understand the consequences of that.

43:02I don't understand how you get it done. So my objection is not to a carbon tax in the abstract. My objection is to how do you actually get it done? And if you say this is the only policy solution that I will accept, is that shutting you off to other ways that we might be able to make a dent? You're listening to People I Mostly Admire. I'm Steve Levitt. And after this short break, Kate Marvel and I will return to talk about why she's probably finding this conversation frustrating.

43:48I spent most of this interview asking Kate about the aspects of climate change that are most interesting to me. Public policy, carbon taxes, geoengineering. As she's made clear several times, these things are actually mostly outside of her area of expertise, which is physics. But it's become commonplace for climate scientists to be asked to fill roles that extend beyond science, acting as advocates for the environment, and more and more, it seems, serving as therapists to people dealing with climate anxiety. Let me just say that as an economist, nobody asked me to be their therapist. I asked Kate if it was frustrating as a climate scientist to be expected to have opinions and thoughts on so many things outside of science.

44:38It's frustrating. It's also just bizarre to me because obviously I would not be a good therapist. Obviously I do not know that much about public policy. And there are people who spend their lives studying these things. Something that I find very confusing and baffling and scary is people expect me to have the correct opinion on literally everything bad that's going on in the world. Climate change really illustrates the interconnectivity of everything. How the ice and the atmosphere and the ocean and the land all talk to each other. But it also illustrates the interconnection of society. And so on a very high level, yes, everything is interrelated.

45:22But it can be extremely overwhelming to ask a climate scientist to have strong opinions on every conflict, every tax policy, every unfairness in the world. They are all related and they all do matter. But I think we only make progress when we zero in on the things that we are actually good at. And I am fundamentally deep in my core a nerd. And I like doing science. I like doing physics. And I think that's where my contribution can be. So you're a physicist, but in your new book, Human Nature, Nine Ways to Feel About Our Changing Planet, you're questioning what it means to be a scientist who feels things about what she's studying.

46:11Could you talk about that? I struggled with this for a while because scientists in general are supposed to be neutral and objective. But I study the Earth, and that means that I have a conflict of interest because everybody and everything that I care about lives here. So I can't be neutral and emotionless. And I worried that if I say I feel things about this planet, is that going to make me less credible? And then I realized that, no, that makes me a liar. And I don't want to be in the business of saying things that are not true. As scientists, we have tried for a really long time to talk about climate change through the prism of science, right?

46:54We've been like, oh, just one more chart and it will convince everybody. Like, hey, look, guys, we have another equation. Now does everybody believe us? And that hasn't worked because that's really not how people relate to information. We like stories and stories make us feel things. I want to be really clear that I haven't said anything productive or useful about emotions in this book. People ask me, I have climate anxiety, what should I do? And I don't know. Go talk to somebody who knows what they're talking about. What I am saying is that it's okay to feel things and it's okay to tell stories about climate change and what it has meant in the past and what it means in the future.

47:34So each chapter of your book has the name of an emotion. Wonder, fear, anger, guilt, grief, surprise, pride, hope, and love. But after reading your book, I think my own overriding emotion is resignation, which is probably not at all what you hope for when you're writing the book. That is not. I have failed utterly. Why do you feel that way? when I think about climate change, actually sit down and think about it carefully and thoughtfully, like your book caused me to do. I'm always left with the feeling like we're not going to crack it and we're just going to ride this thing out and either we're going to be kind of lucky or we're not.

48:20I just don't have enough faith in humanity to think we're going to solve it in a good way. Interestingly, when we wrote Super Freakonomics and everyone got so mad at us, I actually had hope. Because at that time, I had a feeling that science, clever science, really smart people, were going to be the answer to this problem. But I think more and more, I have the sense that this might be a problem the scientists just can't get us out of. I actually am the opposite of you. I have gotten more optimistic as time has gone on, because the problems are getting worse, but the solutions are getting better.

48:55And I agree that it is overwhelming to look at this on a global scale and say, are human beings good? Yes, no. If you frame it that way, then you are always going to have a pessimistic outlook. Because if it requires human beings to be uniformly selfless and good, then yes, we will never get out of this. But I actually don't think we need hope. People always ask me if I hope that we can solve climate change. And for me, that's asking, do you hope you can clean the bathroom? I don't know, just clean the bathroom, right? And we do have most of the tools that we need to solve this. And we have had incredible progress on people making solar panels better and cheaper.

49:42We have seen an absolutely stunning decrease in the cost of wind and solar. We are seeing a jaw-dropping decrease in the cost of batteries, to the extent that I think the global energy transition is now inevitable. Will it be fast enough? Will it be fair enough? No, I don't think that. But I think we are looking at a future that is powered very differently than our current world. I am not a defeatist. I think there is still so much to do. and there's still so much joy and purpose and meaning to be found in doing things and actually looking at where does my skill set fit in to helping solve some aspect of this problem.

50:24If you look at it from what needs to be done and what can I do, then you start, just like Mr. Rogers said, you start looking for the helpers and they're everywhere. And that actually does give me hope, even though I don't need it.

50:43It's always interesting to me when two reasonable, thoughtful people like Kate, Marvel, and myself can look at the same set of data, agree on the facts, and still come to opposite conclusions. When I look at where we're heading with the climate, I have the overriding sense that we're on a bad path with little or no chance of getting off. Kate, on the other hand, is optimistic, feeling that the solutions are starting to fall into place. I'm curious, What's your view about our future climate? Are you optimistic or pessimistic about the state of the Earth's climate 50 years from today? I'd love to hear your answer to that question.

51:20Send us an email. The address is pima at freeconomics.com and also your age and the country that you currently live in. Feel free to write as much as you want, but also feel free to write literally a three-word email that has either the word optimistic or the word pessimistic, your age and your country. I'll tally up the responses and report back on them in a future episode.

51:46So this is a point in the show where I bring on my producer, Morgan, to pose a listener question. Hi, Steve. So a listener named Jasper sent us an email with an idea, and he's curious to know your opinion. Jasper proposes that the government should charge one penny for every email sent. the fee would be charged to the sender. Our inboxes fill up with a lot of clutter, and Jasper thinks this could disincentivize senders of spam and promotional emails. He also says that even if one penny per email doesn't prompt anyone to change their behavior, it would be a lot of revenue for the government. So Steve, what do you think of this idea?

52:29I love the idea. I love the way Jasper is thinking. Let me explain why. With the caveat that I'm sure there's a scientific literature that studies optimal message sending. I've never read that literature, so this is just my own impressions. So all of my logic starts from a basic premise, Morgan, which is that I think the sender in general cares more about the message being delivered than the receiver cares about receiving it. And you can think of exceptions, but don't you think that's basically true? Yeah, absolutely. Any business that's sending out a promotional email is doing it for their own self-interest in the hopes that five, 10 % of recipients will open it.

53:11Yeah, but even if you send me an email, usually it's more important to you. And sometimes it's important to me and sometimes it's not. When I send you an email, it's always about this podcast, so it should always be important to you. Okay, so let's think about a world where it's costless for the recipient to receive a message. So if you send me a message, I can just know what it says without having to spend any time or money doing it. Of course, that's not true, right? It takes me time to sift through messages. Even if I don't read the actual message, deleting it from my inbox takes a little bit of time.

53:40It's no accident that snail mail, when you send letters to the post office, it's the sender who pays the postage, not the recipient. And that's in line with what Jasper's talking about here. One other thing I want to bring up. I have long loathed voicemail. It takes as long for the listener to listen to the voicemail as it does for the sender to have recorded it. And that's really inefficient because in general, you want to have technologies where it's relatively hard to send the message and relatively easy to receive the message. And so that's good about email, right? It takes you a lot longer to compose the emails that you send to me than it does for me to read them.

54:20So in general, I think email is moving in the right direction already of putting the burden on the sender. Well, this might be true in a one-to-one basis, but what about emails to thousands of people, like spam? Exactly. You totally nailed where I was going with that, which is you compose a spam email once, and then you send it to 10 ,000 people, and that's incredibly inefficient because almost all of the effort goes to getting rid of the spam and very little to sending it. And that's what we call in economics and negative externality. And how do you deal with negative externalities? well, you want to tax them.

54:54And just like a carbon tax would tax the negative externality of climate change, Jasper's idea would be to tax the negative externality of spam. So I think it's a great idea. So you think this should be enacted? I think it's a good idea, but I think it's impossible to do for the reason that micropayments have never been figured out. I don't know why, but it's turned out that nobody has found a good way to allow people to be charged one cent for doing something. and it would be a great application here if people could pay half a cent or a cent for this. But an equally good application and one that I've been frustrated by for years is how you could use micropayments for podcasts because advertising on podcasts is an incredibly inefficient way of wasting everybody's time listening to ads that most people don't really want to hear.

55:43If instead you could charge someone a penny to download our podcast, that would be better for everyone. and that technology has just been elusive. So what we really need is some super smart listener to figure out how to create a world in which micropayments are possible. And once that happens, then Jasper, the first thing I do is I tell the government to apply it to emails, just like you said. Jasper, thanks for writing and great idea. Listeners, if you have an idea for us or a problem that could use an economic solution, send us an email. Our email is pima at freakonomics.com. That's P-I-M-A at freakonomics.com.

56:23Steve and I read every email that's sent, and we look forward to reading yours. Next week, we've got an encore presentation of a conversation I had with my good friend and former Secretary of Education, Arnie Duncan. And in two weeks, we've got a brand new episode featuring behavioral scientist Yuri Simonson. He's both an incredibly inventive and productive academic, and he's been at the center of efforts to catch cheating academics. As always, thanks for listening and we'll see you back soon. People I Mostly Admire is part of the Freakonomics Radio Network, which also includes Freakonomics Radio and the economics of everyday things.

57:04All our shows are produced by Stitcher and Renbud Radio. This episode was produced by Morgan Levy and mixed by Jasmine Klinger. We had research assistance from Daniel Moritz Rapson. Our theme music was composed by Luis Guerra. We can be reached at pima at Freakonomics.com. That's P-I-M-A at Freakonomics.com. Thanks for listening.

57:31Oh man, I mean, talk about the things that I am not an expert in. The psychology of weird rich people is probably number one.

57:42The Freakonomics Radio Network The hidden side of everything

57:50Stitcher