Fighting the Climate Crisis, With Gernot Wagner

Jim Lindsay:

Welcome to the President's Inbox, a CFR podcast about the foreign policy challenges facing the United States. I'm Jim Lindsay, Director of Studies at The Council on Foreign Relations. This week's topic is Combating Climate Change. With me to discuss what role technologies like nuclear power, carbon capture, or solar geoengineering might play in combating climate change and what risks and dangers they could pose is Gernot Wagner. Gernot is a climate economist at the Columbia Business School. His work focuses on climate risks and climate policy. He has written four books, the most recent of which is Geoengineering: The Gamble. He also writes a monthly column for Project Syndicate on climate change. Gernot, thanks for being here.

Gernot Wagner:
 

Thanks for having me.

Jim Lindsay:

I want to begin our conversation with two broad observations. The first is that our climate is changing and the consequences are potentially catastrophic. We see the signs all about us. Europe is currently experiencing its most intense drought in 500 years. Pakistan has the opposite problem, torrential rain and flooding that has already killed more than 1,000 people. A study released earlier this week concluded that the melting of the Greenland ice sheet will cause oceans to rise by nearly a foot by the end of the century, which would put low lying coastal areas, think Florida as well as Bangladesh, underwater.

Jim Lindsay:

Second observation is that despite all of the international summits, all of the agreements and vows by world leaders, the emission of the heat trapping gases that drive climate change continues to rise. In all we seem to be playing out the dynamic capture in St. Augustine's famous prayer, "Give me chastity and continence, but not yet." So Gernot, is it time for us to rethink our approach to combating climate change by leaning more heavily on nuclear energy, developing technology to remove carbon from the atmosphere, or take a shot at solar geoengineering?

Gernot Wagner:
 

Yes and no. And let me start with a no. So I mean, yes, things are bad. Frankly, things are bad and much, much worse than most of us predicted. So this Greenland study you just mentioned, it wasn't too long ago that frankly, most of us of course understood that the poles are melting and sea levels are rising, but then when you added it up, Greenland summer sea ice is melting and that's a real problem, but the Greenland ice sheet itself, isn't going to contribute all that much to sea level rise this century. Nah.

Gernot Wagner:
 

Now, to be clear, it was never a question of if New York City is going to be underwater, it's a question of when. But of course when matters. If it's thousands of years from now, happening within a millennium, yes, that's a problem. But of course not as big a problem as 10 million, 30 million by some counts. In Pakistan right now directly affected by massive, massive floods, 1,000 people dead. Not a future event, happening now, happening this week. Climate change is hitting. On the other side, and this is the optimist in me, there is this clean energy race that is happening much, much faster, significantly faster than also most of us predicted not too long ago.

Jim Lindsay:

But the issue isn't whether it's happening faster than we predicted, it's whether it's happening fast enough to blunt the change in the climate.

Gernot Wagner:
 

Of course. And no, it is not. That said, yes, there are negative tipping points. Negative climatic, tipping points, that's the Greenland ice sheet collapsing completely and so on and so forth. There are also positive ones. There are positive socioeconomic ones. There are all these facts around, we are installing more solar PV this year than the International Energy Agency predicted would happen by 2030, five years ago. So prediction five years ago said we are massively ramping up solar PV deployment, solar photovoltaic. And this massive increase will lead to amazing deployment by the end of the decade. We are there right now, already. And this is the hopeful side. This is the optimistic side, that no, it's not just carbon removal, solar geoengineering. Yes, we need that too, potentially. Potentially the solar geoengineering bit. Carbon removal, yes, we need that. We pretty much know that already. But there is still so much on the clean energy front.

Jim Lindsay:

So let's play out that positive story, Gernot, on the clean energy front. To what extent do the provisions in the recently passed Inflation Reduction Act make a difference both domestically in the United States, but potentially broader overseas?

Gernot Wagner:
 

And that's exactly, that's one of these tipping points. It is the biggest climate investment in U.S. history. And by the way, when you sort just go through the numbers here, sort of the headline figure, many of us are familiar with, is this $369 billion over 10 years in clean energy investment. Turns out there is another $100 billion in loans to EV production, electric vehicle, battery production facilities. And the Department of Energy is getting $250 billion in additional loan authority to lend to clean energy efforts. That's another 350 billion right there, almost doubling this headline figure of investment. And of course, whether it's the end of the beginning or the beginning of the end, I'll let others chime in on this one, but it's just the beginning. It is just the very first time that we at the national level invest heavily in this clean energy race. And yes, it's a race.

Jim Lindsay:

How is it a race? Is it a race against time or is it a race against other countries?

Gernot Wagner:
 

It's both. So let's start with the race against other countries. So actually it was The Economist, the magazine, that put, "From Petro State to Electro State," on its cover a couple years ago. And as some of the headline figures in there, and of course they've only gotten bigger since. China produces over two-thirds of all solar panels produced globally. Over two-thirds, 70% of all lithium-ion batteries produced globally in any given year are produced or manufactured in China. Almost half of wind turbines in China. Okay. So, I mean, that's the electro state right there. A massive, massive industrial policy effort to win the race for the technologies of the future. And yes, China has been leading the charge on the supply side. Europe arguably has been leading the charge on the demand side. And the U.S. in many ways at the national level has been sitting on the sidelines.

Gernot Wagner:
 

Well, it just entered that race in a big way. And of course it's only really a race, if other countries are not just sitting there watching and sort of applauding saying, "Hey, finally. Welcome." But in fact are doubling down themselves. And we see some of that. So actually before the Inflation Reduction Act passed, I would've argued, and many of us argued and saw in the data, this real transatlantic divergence in how we reacted to Putin's invasion of Ukraine. Lots happening in Europe, very little on the clean energy front happening at the national level in the U.S., at least nothing really in addition to what had happened before.

Gernot Wagner:
 

Well, suddenly the U.S. entered this in a big way. So is it enough? No, it is not. We are still losing the battle against time. The battle against climate change, unmitigated climate change. But well, those are the positive tipping points. Those are the socioeconomic ones, or heat pumps, electric vehicles. Or still frankly, to this day, the sort of thing that some of us invest in, some of us do, some of us are willing to take the step. Look, it's not going to take long for heat pumps, well-insulated buildings, electric vehicles, to be the default, to basically be the sort of thing that hey, that's just what you do.

Jim Lindsay:

You write a lot about heat pumps, Gernot, what do you mean by that and why are they significant? My guess is most people in the United States are not familiar with what a heat pump is or does.

Gernot Wagner:
 

It's a refrigerator you can run in reverse. So you can also use it to heat your home. Or sort of the flippant version is sort of, it's an air conditioner, but it's actually the functioning is sort of closer to a fridge, if you will. But it's basically a way to heat and cool your apartment, your home, your office, with the same gadget, the same pump, called the heat pump, that replaces your air conditioner on the one hand and replaces typically the gas furnace on the other.

Jim Lindsay:

And it uses less energy?

Gernot Wagner:
 

It uses a lot less energy. It's electric. The name of the game in this clean energy race basically is insulate, insulate, insulate, electrify, electrify, electrify. And then of course you need to decarbonize the electric grid, that's a key component of course too. But actually even if the entire grid ran on natural gas in this case, it's still better to then use an electric heat pump to cool and warm your home than to burn gas directly in your home. So in this electrification business, heat pumps play a major role.

Gernot Wagner:
 

And then of course, sort of the final step, if you will, doesn't use a lot of gas turns out, but the final step to not need to burn any gas in your home is then to switch your stove from the gas range to the induction stove. And in many ways that's the gold standard as it were. And it's increasingly becoming the norm. The Inflation Reduction Act subsidizes those heat pumps to the tune of some like $8,000 per home per heat pump. And by the way, subsidizes it by way of a rebate, not a tax credit you may or may not get come April 15th of next year. But you get it right then and there when you buy the thing.

Jim Lindsay:

Now, one question for you, Gernot, because I've heard a lot of people talking about the green energy transition, talk about the cost, but they also talk about constraints or choke points, that as you move to green energy you need access to more minerals that you hadn't previously used. They're in short supply, we talk a lot about rare earth minerals and things like that. Is that a real sort of choke point in this transition to green technology?

Gernot Wagner:
 

It is not. It is not at this point and it is not in the sense that we are not anywhere close to hitting any of these limits. And frankly, yeah, we see some of this sometimes. This is sort of the birthing woes of a new industry, of course. So there is a shortage in a particular component and then it turns out we innovate our way out of. And when you look at the overall trends, solar PV of course is sort of the one most of us know about, and it costs now a tenth of what it did 10 years ago. It costs a hundredth of what it did 40 years ago when Jimmy Carter put solar panels on the White House, and five years later, Ronald Reagan took them down.

Gernot Wagner:
 

Nobody's going to take down a solar panel right now because it is the cheapest form of electricity in history. And yes, solar PV did increase in price slightly this year over last year, like so many other things did. And yes, shortages and some components are partly to blame. But the increase from last year to this year, around 20%. Increasing the alternatives, fossil energy tenfold. Triple, quadruple, tenfold in Europe, natural gas prices. So in other words, the price that actually matters, the relative price, solar PV is even cheaper this year than the fossil alternative.

Jim Lindsay:

But you're going to need a lot more lithium. Do we face constraints in terms of access to lithium? I take your point that scientists given enough time can find substitution, maybe find a different chemical that will allow you to have even more efficient battery, but that can take time.

Gernot Wagner:
 

It does and up to a point. So yes. So if your world is a race between fossilflation and greenflation. So this European central banker Isabel Schnabel, who had introduced those two terms. And actually before the invasion, before February 24th, gave the speech where she introduced both terms and basically voiced her concern about greenflation. And I can tell you, to her full credit, almost immediately after, she came out swinging and said, "Look, the reason for the inflation we see right now is in fact, increase in fossil fuel prices, is fossilflation." And yes, there's always going to be components of the batteries are getting more expensive or right now, electric vehicles are extremely expensive in the sense that you pay above manufacturers’ suggested retail prices because there's just so much demand right now for these things.

Gernot Wagner:
 

Well, it turns out that EVs, batteries. renewables, for the matter, are in fact all technologies. And in so many ways, technologies can only get cheaper over time. We get better at doing this stuff. We get better at producing the battery. We find alternatives to lithium. We are more efficient in their use. Whereas the alternative, fossil fuels, are commodities and it shouldn't surprise us anymore 100 years or so into the oil age that those prices fluctuate wildly. And while of course, we also get better at using limited resources up to a point, well up to a point we use that us getting better of using limited resources to then for example, drive bigger cars, SUVs and so on. And that in itself, of course is a problem and no EVs aren't going to solve everything. But again, one is a technology, the other one a commodity. And I'm rather hopeful that we will figure out these technological questions, especially of course, also because that's sort of the international relations here just look very different from technology markets, on the one hand, versus commodity markets.

Jim Lindsay:

Gernot, let's go back to where we started. When I asked the first question about whether it was time to think differently, your answer was yes and no. And we've been talking so far about how there has been progress in the green energy transition, maybe even more than people appreciate. The Inflation Reduction Act among other things are going to make that happen. But my takeaway is still that we're not in a situation in which that transition is happening fast enough. So this gets us into the question of what role should things like nuclear energy, carbon capture and storage, and solar radiation management, also known as geoengineering, play in the battle against climate change?

Gernot Wagner:
 

So first of all, I would say these three of course are very, very different. So nuclear is something we've decades worth of experience. Very different responses in Germany, let's say over the last decade post Fukushima accident versus the U.S. and elsewhere. So lots of geopolitics, lots of intricate questions and frankly, lots of historical perspective. That's one. But the second, carbon removal, still addresses the root cause. Not sort of directly the root causes in too much CO2 emitted, but it addresses the problem of too much CO2 in the atmosphere. And yes, carbon removal, just like the name implies, means literally sucking CO2 out of thin air.

Jim Lindsay:

Are we doing that?

Gernot Wagner:
 

Are we close to doing that? Well, we've been doing it forever. Trees have been doing it forever. They're sort of the natural version, if you will.

Jim Lindsay:

Do we plant trees?

Gernot Wagner:
 

Yes. Of course, I like trees. Trees are fun. Trees are good. We can use more trees. Yes, absolutely. Trees the solution? No. Now, for a few reasons. So one of course, so there are land use trade offs here, very direct ones. Limited land and so on, of course. Another one is trees keep the CO2 in the biosphere. They suck the CO2 out of the atmosphere, which is good, but then trees die, decompose, and the CO2 is released back into the air. So really what we should want to do is take the CO2 out of the atmosphere, out of the biosphere, and put it back where it came from, back into the geosphere, back in the ground. And yes, there too are in fact carbon removal technologies that allow it. They literally, we can basically reverse the chemical processes that we use to burn fossil fuels, release CO2, to take the CO2 out of thin air and put it back underground.

Gernot Wagner:
 

Now that sounds energetically expensive and monetarily expensive. It costs a lot of money right now, and it does. So there's for example, a demonstration plant right now, a Swiss startup, Climeworks, has a plant up in Iceland, Orca plant that takes something like 4,000 tons or so of CO2 out of the atmosphere in a year at the low, low price of somewhere around $1,000, €1,000 actually, per ton of CO2. Okay. That's very expensive relative to frankly, what most of us are willing to pay to offset our own emissions or cut our own emissions.

Gernot Wagner:
 

So one way to look at carbon removal is in fact, a simply expensive mitigation, an expensive way to cut CO2 emissions. So in other words, there is lots and lots of other things we could and should be doing now, before we get there. And now we're back to the clean energy race. With that said, if we want to be at a stage in two, three decades to be sucking CO2 out of the atmosphere at scale, we better start now. We'd better pay, or willing to pay 1,000 bucks a ton today to get it down to $500, $200, $100 per ton of CO2 sooner rather than later.

Jim Lindsay:

I mean, isn't there a risk, or at least I've heard it phrased as a risk, that if you spend a lot of time and energy on carbon capture and sequestration and storing it, that you're going to take away from what should be our fundamental challenge, which is simply not to put the emissions in the air in the first place, and in some sense, what'll happen is it will just encourage us to put more heat-trapping gases into the atmosphere?

Gernot Wagner:
 

Absolutely. I mean, the risk often goes under the name of moral hazard. It basically allows us-

Jim Lindsay:

Like car insurance and you drive faster.

Gernot Wagner:
 

Exactly. Or you put on your seatbelt and you drive faster. And sort of in many ways, yes, that phenomenon exists. It's ever present if you will. And to be clear, some of this moral hazard is good. As in getting places faster is in fact a feature, not a flaw. So if you're driving with a seatbelt means that you get there faster and more safely. Great. But of course, some of these conversations get very controversial very quickly, and sort of not to get too political, but the political right basically often points to health insurance, or universal healthcare as sort of, oh, that creates all this moral hazard. It's the government taking care of you when you get sick. Shouldn't you be taking care of your own body? Or for the matter reproductive technologies, condoms instead of your classic moral hazard technology.

Jim Lindsay:

You are the first person to mention the word condom on the President's Inbox.

Gernot Wagner:
 

On this podcast? Okay. Well let me shift immediately from condoms to solar geoengineering or carbon removal, because yeah, it has the same features. There's a technology that we know works. It does work. The condoms work as advertised, turns out. Now, if you don't like the behavior that leads you to need to use condoms, then you may object to it on the grounds of moral hazards, because it allows stuff that you find icky to happen safely. Well, back to carbon removal, same idea. Now it's not the political right now, it's the political left if you will, who might object to carbon removal as a technology because it allows us to keep burning fossil fuel.

Gernot Wagner:
 

And just to be clear, it of course gets much, much more complicated very quickly. First of all, who is the us here? Who is the we? It's not like that there's some benevolent, omniscient decision maker who makes some sort of rational decision of what the right mix is of burning fossil fuels now versus sucking CO2 back out. No, of course not. It's vested interests that are going to spam your Twitter feed with ads, telling you how great carbon removal technologies are and sort of subconsciously wanting you to believe that, oh, fossil fuels are not that much a problem after all, because look, technology already exists. We can suck it back up.

Jim Lindsay:

Gernot, is that why energy companies, fossil fuel companies have invested so heavily in carbon capture?

Gernot Wagner:
 

In part, yes, of course. I mean, okay. And now there's sort of definitely two sides to this. So if you had to pick, objectively pick a company that you would think is best equipped to in fact, just do the technical... Scale up the technology, finance it, go do it. Suck CO2 back out of thin air. It's presumably the companies that already have the pipelines, the companies that have the technology that have dealt with carbon for a century of their existence and so on. And to basically convert energy, oil and gas companies into carbon management companies that sooner rather than later do in fact start sucking CO2 out of thin air. Sure.

Gernot Wagner:
 

On the other hand, of course, it now allows Exxon to sponsor a Reuters News story about this Climeworks demonstration plant in Iceland I just mentioned on my Twitter feed, literally. Sort of hundreds of thousands of views for this video that Reuters produced, news agency produced about this Climeworks demonstration plant. And on the very bottom of that sponsored Twitter ad, it says sponsored by Exxon. So yes, it is a problem when vested interest basically promotes this technology in hopes of us easing off climate policies and not instituting the sort of policies that would lead us to cut fossil fuel use in the first place.

Gernot Wagner:
 

And now it gets very complicated very quickly, because it is no longer the case that there's some sort of rational decision maker trying to balance the benefits and the costs. But basically it's a for-profit enterprise, trying to keep the status quo longer in order to let's squeeze in yet another quarterly earnings call before the carbon tax, the carbon price, the regulation hits. But frankly, that goes now well beyond moral hazard. It is no longer the economist's definition of moral hazard, where you, as the rational human being, now react to a rule that forces you to use seat belts in a way that you drive faster. But now it's different decision makers, vested interests, competing in the marketplace of ideas, competing in Washington and their lobbying efforts and that sort.

Jim Lindsay:

Let's talk about solar geoengineering. What role does that play? What state is the technology in? What are the moral hazards that arise when we talk about solar geoengineering?

Gernot Wagner:
 

So the moral hazards are very similar to nuclear on the one hand, carbon removal on the other. The technology itself is very different. So solar geoengineering essentially is an attempt to brighten the planet at a large scale, to cool it. To intervene directly by basically changing the planet's albedo, its brightness.

Jim Lindsay:

The idea is to reflect radiation coming from the sun back out into space.

Gernot Wagner:
 

Exactly. To reflect back. All right, in a very simple term, you can sort of think of it, why do we wear white between Memorial and Labor day and why are winter coats black? Black absorbs the heat, energy warms what is underneath. White reflects and cools what is underneath.

Jim Lindsay:

And obviously with the melting of the polar ice caps, you have a decrease in the Earth's albedo.

Gernot Wagner:
 

You do. And that's a very negative feedback effect, because now you increase global warming even more so, because suddenly the poles are less bright. So at a global level, maybe the most prominent solar geoengineering technology, if you will, is mimicking volcanoes. When Mount Pinatubo erupts in the Philippines in 1991 and releases quite a bit of gunk into the stratosphere, global average temperatures in 1992, ironically right around the time of the Rio Earth Summit, the first time we all got together in June, July '92, global average temperatures were about half a degree centigrade, almost a degree Fahrenheit cooler than they would've been without the volcanic eruption.

Gernot Wagner:
 

Now there's a few things here. So one, that stuff falls out again, those aerosols, tiny reflective particles, sulfate aerosols in this case, fall out and sort of 18 months later, global average temperatures are back to where they would've been entirely without the volcanic eruption. And of course, temperatures have risen ever since. That's one feature of this potential intervention that some might consider a problem. I would consider in fact, to be a feature. It's sort of an, unlike CO2 or 40% of the CO2 we emit today is still there 1,000 years from now. With stratospheric aerosols, with solar geoengineering, you in some sense have much more control over what happens. Or for that matter if you don't like it and you stop 18 months later, it's gone. Now, nothing ever is as simple as the simplistic description might lead you to believe. But yes, that's certainly a feature of this intervention that is in fact good, I would say. This controllability. Now what's not good of course, is that there are plenty of risks associated with this potential intervention.

Jim Lindsay:

What would those risks be?

Gernot Wagner:
 

Well, frankly, one is moral hazard. That's of course not the sort of risk that you first think about because you would think of physical risks first, but I would say actually maybe the most important risk overall, in its overall impact might in fact be this a moral hazard component of solar engineering. You and me talking about it. The mere fact that we now spent the time talking about solar engineering and not solar panels, others might say you're taking the eyes off the ball here, you're not focused on what you should be focused on.

Gernot Wagner:
 

Now in terms of physical risks, I would say the more one studies this, the better it seems to look in the sense that yes, there are physical risks. There is for example, an interaction of the sulfate aerosols with stratospheric ozone. With the protective ozone layer in the stratosphere. And yes, when Pinatubo erupted, the ozone hole over the Antarctic opened up a bit again. That's a problem, of course it is.

Jim Lindsay:

And it's a problem because?

Gernot Wagner:
 

Because we like stratospheric ozone. We don't like it down here. We don't like it in L.A. because of all the traffic, but we like ozone in the stratosphere because it is this protective layer that by the way, we worked very, very hard in the late 80s to pass the Montreal Protocol, to ratify the Montreal Protocol and to basically begin this healing process of the stratosphere, phase out the offending substances and fix the ozone hole. Solar geoengineering wouldn't reopen the ozone hole, but it would delay the healing process.

Gernot Wagner:
 

If you were to do solar geoengineering with sulfate aerosols, with sulfate, turns out there might be the potential to use different substances. Calcium carbonate tested in a lab, modeled in climate model runs, might have even better optical properties than sulfate aerosols. So it might be doing better on that front. And it's a base, not an acid. It doesn't muck with the ozone hole. If anything, it leads to what's sometimes called ozone super recovery. Suddenly you get too much of the ozone, which of course is its own risk. All that's to say is, yes, there is a lot more research to be done on this topic.

Jim Lindsay:

Have we actually done research on this? My sense is that there's a lot of resistance to conducting large scale tests of what critics call geoengineering, what proponents would call things like solar radiation management or solar climate intervention.

Gernot Wagner:
 

So we haven't done any outdoor experiments, or little ones here and there, but sort of nothing of significance. There are hundreds of peer reviewed papers by now, most of them focused on climate model runs. So has there been research on this topic? Yes, absolutely. And actually most of it happened over the last decade or so. The idea has been around for a while, since the 60s, 70s. But it was basically a longstanding self-imposed moratorium if you will, by scientists, by climate scientists. And I would once again point to moral hazard as taking the brunt of the blame here. Climate scientists, basically self-censoring because they were afraid of this moral hazard component. Taking eyes off the ball of needing to cut CO2 emissions in the first place.

Gernot Wagner:
 

Now, interestingly enough, who broke the taboo or who helped break the taboo in a big way? It was the late great Paul Crutzen who won the Nobel Prize, shared the Nobel Prize for work leading up to the Montreal Protocol, to the discovery of the ozone hole and then the work to fix it. And he basically wrote this speculative essay, 15 or so years ago by now, that basically said, "Wait, we have way too much local air pollution, killing millions of people down here. If we were to stop that, and of course we should, the planet would warm quite a bit very quickly because that air pollution down here is also mostly in the form of tiny reflective particles cooling the planet."

Gernot Wagner:
 

So he sort of wrote this essay, basically asking the question, wouldn't it be a reasonable thing to want to do, to both cut the pollution down here and at the same time deliberately introduce a small fraction of that pollution into the stratosphere where nobody lives, of course, where it has much fewer negative health effects, basically in an attempt to stabilize temperatures while we clean up the mess down here that local air pollution causes? And in some sense the fact that Mr. Ozone Hole, who won the Nobel Prize for the discovery and so on would write this, would speculate that this might be a trade-off worth contemplating. In some sense, broke this long standing taboo, self-imposed moratorium of research. And in the last 10, 15 years, we've seen this exponential increase in attention paid to this topic. And by now we have hundreds, 800 or so at last count peer reviewed papers on this topic.

Jim Lindsay:

So the argument for solar radiation management is that in theory, it could buy time to actually have the green transition fully go forth. The risk is that if it succeeded, that you might never actually make that transition, because you'd be protected by this solar radiation management.

Gernot Wagner:
 

So I would say I don't quite buy these sort of buying time argument here, because at the end of the day, I mean, we just have to race as fast as possible toward this clean energy future. Full stop. That's priorities, one through however, ten. This climate policy or cut CO2 emissions. Insulate, insulate, insulate, electrify, electrify, electrify. Decarbonize, the grid and so on and so forth. What solar geoengineering might in fact do. And again, at this point, because we're at the stage where we ought to be doing more research on this topic, it's not about deploying it next year or anytime soon, it's doing the research.

Gernot Wagner:
 

But what it might do is it might actually save quite a few people right now while we are in the stage where we have not cut CO2 emissions sufficiently, where we have warmed the planet by over a degree centigrade, two degrees fahrenheit already and where we do see floods devastating Pakistan with 1,000 people dead this week and 10 to 30 million people affected. And droughts in China and heatwave in Europe and the western U.S. burning and so on and so forth. So there are plenty of bad effects already. Climate change is already hitting home. And yes on balance, this is a risk, risk trade-off conversation here. Maybe solar geoengineering could in fact do quite a bit of good right now, not as a replacement for cutting CO2 emissions, but largely because we have in fact warmed the planet by over a degree centigrade, two degrees Fahrenheit already. And because climate impacts, climate damages are already hitting home.

Jim Lindsay:

On that sobering note I'll close up the President's Inbox for this week. My guest has been Gernot Wagner, a climate economist at Columbia University's Business School. Gernot, thank you for joining me.

Gernot Wagner:
 

Thanks so much.

Jim Lindsay:

Please subscribe to the President's Inbox on Apple Podcasts, Google Podcasts, Spotify, or wherever you listen. And leave us a review, we'd love the feedback. You can find the books and articles mentioned in this episode, as well as a transcript of our conversation on the podcast page for The President's Inbox on cfr.org. As always, opinions expressed in The President's Inbox are solely those of the host or our guests, not of CFR, which takes no institutional positions on matters of policy. Today's episode was produced by Rafaela Siewert with senior podcast producer, Gabrielle Sierra. Rafaela was our recording engineer. Thank you, Raf. Special thanks go out to Margaret Gach for her assistance. This is Jim Lindsay. Thanks for listening.