Climate Now Debates: Solar Radiation Management (SRM)

James Lawler: Welcome to Climate Now, a podcast that explores and explains the ideas, technologies, and the practical solutions that we’ll need to address the global climate emergency. I’m your host, James Lawler.

In September of 2023, the United Nations published a report, and for new listeners, anytime we say here at Climate Now that there’s a report that someone published or that we cite a fact, we always provide the link to that reference in the transcripts on our website, climatenow.com. So you can go there if you want to delve deeper into anything we’re talking about. Anyway, the UN report states that “the window of opportunity to secure a livable and sustainable future for all is rapidly closing.” The UN found that global emissions are not in line with the modeled global mitigation pathways and at our current rate, we have a rapidly narrowing window to act in order to limit global warming to 1.5 degrees Celsius or 2.7 degrees Fahrenheit above pre-industrial levels. At this point, everyone on Earth is feeling the impacts of climate change to some degree. We are already seeing massive damage to infrastructure, reductions in crop production, heat induced worker productivity losses, losses due to tropical cyclones, and species extinction.

As the planet warms, every fraction of a degree of temperature increase makes those impacts worse. In its most recent report, the Intergovernmental Panel on Climate Change, or IPCC, explains how even a rise of just one and a half degrees Celsius on average could result in widespread drought for nearly one billion people, 14 percent global biodiversity loss, and $63 billion of lost global food supplies. Exceeding the 1.5 degrees threshold would worsen those impacts, potentially catastrophically.

Since warming is so closely linked to greenhouse gas emissions, it’s clear that to reduce future warming, we need to reduce emissions as quickly as possible. But, according to the National Oceanic and Atmospheric Administration, greenhouse gas emissions continue to rise in 2022, further impacting global temperatures. Which begs the question, while we work towards emissions reductions, is there anything else we can do to slow down or even reverse global warming?

In today’s episode, we focus on one such option, that is solar radiation management, otherwise known as SRM, or solar geoengineering. The basic concept of SRM is to reduce the amount of radiation that the Earth receives from the sun by reflecting it back into space.

Doing so, in theory, would lead to a decrease in global warming. Some pro SRM advocates point to volcanoes as one example of a natural SRM-like process that can reduce global temperatures. Most notably, Mount Pinatubo. When Mount Pinatubo, a volcano in the Philippines, erupted in 1991, it launched at least 17 million tons of sulfur dioxide into the atmosphere, according to the United States Geological Survey.

As the sulfur dioxide particles spread across the atmosphere from that eruption, reflecting sunlight back into space, global temperatures decreased by about 0.5 degrees Celsius over the next year. After a few years, however, those impacts subsided.

Today, SRM researchers are exploring a wide variety of methods to cool the planet by reflecting sunlight. One technique being researched is called stratospheric aerosol injection, which involves injecting aerosolized particles into the stratosphere to reflect solar radiation before it hits the Earth’s surface. Another method involves using salt particles to seed more reflective clouds, a method that is called marine cloud brightening.

Other ideas include putting reflective paint on roofs and open ground surfaces, genetically modifying plants to have more reflective leaves, and even putting colossal mirrors into orbit. And if any of our listeners want to read about any of those options, please, as I mentioned earlier, go to our transcript, we’ve linked to see interesting articles about all of those things. But none of these things have actually been attempted at any significant scale—yet.

SRM is highly controversial. The IPCC states that proposed SRM techniques, “face large uncertainties and knowledge gaps, as well as substantial risks and institutional and social constraints to deployment related to governance, ethics, and impacts on sustainable development.” Because of those uncertainties, many scientists and policy makers across the globe have called for a global ban on SRM research, claiming that even the act of researching how we might intentionally tamper with the climate on a global scale is far too risky.

Advocates of SRM argue that the theoretical risks are justified in the face of the certain devastation that will be brought on by the changing climate. And in the middle are those who argue that while SRM may prove to be too risky or impractical, it is at least worth researching to try to clarify what the potential risks or gains would be.

On today’s episode, we will hear from all sides of the argument on SRM. Climate Now has brought together five researchers at the forefront of the debate on SRM research and deployment. First, I moderate a discussion between Frank Biermann, who is Professor of Global Sustainability Governance at Utrecht University in the Netherlands, and University of Chicago Geophysicist Professor David Keith about the merits of a global ban on SRM research.

Next, I speak with Dr. Chukwumerije Okereke, who directs the Center for Climate Change and Development at Alex Ekwueme Federal University in Nigeria. We discuss how SRM would hypothetically impact Africa and why he stands so firmly against any sort of SRM development or research.

Finally, we’ll hear from Dr. Jennie Stephens, a sustainability professor at Northeastern University, in conversation with climate physicist Dr. Claudia Wieners of Utrecht University about whether the risks of SRM research to vulnerable communities outweigh its possible benefits. We hope you enjoy this special Climate Now Debates episode. Thank you for listening.

While research on solar radiation management techniques, risks, and rewards is taking place across companies, universities, and governments today, some people are calling for a halt to SRM development and research. One of these is Dr. Frank Biermann, Professor of Global Sustainability Governance at Utrecht University in the Netherlands, who believes that this literally world altering technology would be ungovernable and prone to exploitation by bad actors.

Offering a differing perspective is University of Chicago geophysicist David Keith, who believes that while SRM should be approached with caution, there is no reason to avoid at least researching it as a potential supplement to existing carbon reduction and carbon capture methods. Here is that conversation.

Dr. David Keith of University of Chicago and Dr. Frank Biermann of Utrecht University. Welcome to both of you.

David Keith: Good to be here.

Frank Biermann: Good to be here. Thank you.

James Lawler: So I’d like to start with some bios and background if, if we could. And Frank, would you mind just giving us your bio and what your work has entailed in particular, what your interest and focus is on SRM?

Frank Biermann: My name is Frank Biermann. I’m a professor of Global Sustainability Governance at Utrecht University in the Netherlands. I’m a political scientist and an international lawyer by training, and I have been specializing in the field of global climate policy for about 30 years, among many other issues that I also attended to.

I’m approaching the field of solar geoengineering or SRM, solar radiation management, I’m approaching this from a political science perspective. My question is, would solar geoengineering work as a political intervention and how would it play out in in world politics? And based on this analysis and discussions and consultations with many of my colleagues, including from the natural sciences, actually, I came to the conclusion to be very critical of the prospect of development of SRM solar geoengineering technologies.

I’m arguing together with 450 other international scholars from 61 countries We are arguing together for an international non-use agreement on solar engineering. We are calling upon governments, the United Nations and technically actually on anybody who has a stake in these matters to support this call for an international non-use agreement on solar geoengineering.

James Lawler: Thanks, Frank. David, same question to you.

David Keith: I got sort of pulled into climate science and then into public policy starting in the late 80s through a really unusual kind of bottom-up group of students at MIT and Harvard who were, I think, really ahead of their professors, which is often true in these cases, who really were thinking about global change in a kind of integrative way.

And from there to Carnegie Mellon, a group that had done work on ensuring and public policy aspects. I’ve kind of wandered back and forth between that and really focused not just on climate, but on environmental policy more broadly. I worked a little bit on SRM early on and then didn’t for a long time, worked on other issues of energy transition, especially electricity sector decarbonization. And then the last decade at Harvard, I came back to really focus on building a more serious effort around, around solar geoengineering.

James Lawler: Excellent. So before we dive in, for our listeners who have not heard of solar radiation management, how does SRM compare to other climate change mitigation strategies, namely emissions reduction and carbon removal? David let’s start with you.

David Keith: A crucial real piece of climate science that is kind of robust and widely agreed is that warming is roughly proportional to cumulative emissions. What that means is that if we bring emissions to zero, we don’t solve the climate problem, we don’t make climate change less bad, we just stop making it worse. Which is great, but it’s very different from thinking about other pollutant problems like, say, air pollution.

If we manage to stop putting the air pollutants in the atmosphere, then you get the cleaning effect very quickly, but that’s not true of climate. So I think cutting emissions is crucial, but if you are unhappy with the warming you’ve got, and in the long run you want to cool it down, then you need to be able to remove carbon.

And so if you ask me that as a voter, how I divide my efforts in terms of total money right now, I put basically zero into SRM, I’d put like 1 percent or something into CDR and carbon removal. But then the split between emissions cuts and adaptation is not so clear. And that’s where different people who live in different places and suffer in different ways will have different views.

James Lawler: Okay, so I would like to come back to that. But Frank, turning to you, how do you see the challenge of climate change mitigation? Obviously, we understand that you would advocate for no SRM. Would that be ever, we shouldn’t consider this as part of our basket of tools? And if so, you know, why?

Frank Biermann: Well, I think, surprisingly, I would agree that SRM, that you should not invest anything in SRM, I fully agree. SRM is, is not a technology where I would invest money right now and I have a number of arguments where I believe that SRM is ungovernable, is too risky, and it is also not needed. Here I would like to refer to the IPCC; the IPCC is the main scientific authority in this field where hundreds, or thousands, of scientists are working together assessing all the scientific literature.

And the IPCC is very clear that we can achieve the 1.5 degree global warming, I wouldn’t call it a target, I call it more a boundary, that we could achieve it in the long term by drastically reducing the carbon dioxide and other greenhouse gas emissions right now. This is in the IPCC. So the IPCC, the models, if you look at them, they say that drastic emission reductions could actually be sufficient to reduce the global warming and the atmospheric concentrations over time. The question is, can we achieve this?

I think this is sometimes the disagreement within the SRM supporters who are quite pessimistic about the state of current climate policy.

James Lawler: Okay, so to clarify then, you both agree that there should be no short-term deployment of SRM. And David, on the long-term deployment, where do you stand on that?

David Keith: I don’t know. I think it depends on what research reveals, especially what research reveals as there’s more chance to try and break the potential groupthink to try and critically examine early work and find out ways it might be wrong to do it in a much more global and inclusive way, and to have the discussions about governance.

I actually think that it’s quite an extraordinary claim Frank is making to say that it’s ungovernable as if that’s a kind of a binary thing that one could know with confidence, which strikes me as kind of beyond the ability of social science to know. Because people have made statements like that before similarly about the internet or penicillin or electricity or lots of other technologies, fifty or a hundred years ago and I think things do not turn out to be so binary in the world we actually live in.

Frank Biermann: I think the comparison with penicillin or the internet is extremely flawed. I mean, to start with. I mean, this is kind of not a technology that can be unilaterally governed by one country and kind of a planetary impact that is majorly harmful for many, many people. I think this comparison is wrong.

Number two, for the science, both the natural and the social science, nobody knows. David doesn’t know, we don’t know, we don’t know what this future brings. David is basing his science in a sense or his approach on models. That’s what people do. They’re running climate models, and these models can turn out correct, they can turn out not correct. The only way to knowing this is to have a global experiment. It’s a planetary experiment with eight billion people that would have to be we sit here and wait and wait and wait and hope that the scientific models are turning out alright. And this is a risk, David mentioned the voters, a risk I do not want to take.

And I don’t want to put anybody into this unnecessary risk because they are other alternatives. The real solutions – which is mitigation, emissions cutting, getting down the emission; that is possible. This is what the majority of scientists are arguing that these emission cuts are possible. So let’s go this way, get down these emissions. Number one.

And number two, for the governance, I studied very carefully the governance literature for many of the supporters from SRM and they’re all kind of having different ideas. The bottom line is we have one organization right now: We have a global governance system run by the United Nations. I’ve just been to New York to the High-Level Political Forum of Sustainable Development, [and I have studied] for 30 years these kind of mechanisms that we have right now: and there are not in any position to run a solar radiation management program as it would be needed.

James Lawler: Before we go on, and David, I know you have thoughts on that and I have some questions too, but we haven’t really talked about why there is any concern at all about these technologies. So for someone who has never heard of SRM before, I’d like to just run through what the perceived risks are, you know, that you each have, right?

Why would you each say that you’re in favor of a short-term moratorium on SRM? What are the reasons for that? And then we’ll come back to where we just left off in the conversation. Frank, can you, and then David, I’d like you also to provide some of these, what are some of the, what are some of the perceived risks of SRM that were, that, you know, you’re both concerned about? Frank?

Frank Biermann: There’s three risks. I mean, the one I mentioned, the geopolitical tension. It will lead to a geopolitical mess. That’s kind of one thing that I’m very certain. The main point with SRM, it’s a technology that can be used, developed, and deployed by any mid-sized country. I mean, that’s kind of, so yeah, I mean, David knows, I mean, there’s lots of these studies about, I mean, how many airplanes you would use, but there are a couple of countries that would be able to run these technologies from their own capacities. So that’s kind of a huge risk, so you would require a global mechanism to control deployment of these technologies in all of these countries. Uh, and that is something that we don’t have much experience with in the global governance system. That’s number one.

Number two is what we haven’t mentioned yet. There is a huge risk. I mean, there’s one on the natural science part, destructive damages and a risk to the planetary system. But the other part is also, there is a risk that the development and the debates that we are having here has a negative impact on the motivation of political actors to engage in the mitigation pathways as we have.

And it’s sometimes called in the technical way it’s called mitigation deterrence; it essentially means that ideas could be hijacked and could lead to a derailing and a delay of the current emission reduction policies that we urgently need.

David Keith: For me, I can certainly think of scenarios that are terrible, but I can also think of scenarios that are good.

And this doesn’t require me to believe in global self-government or that everybody is in some utopian thing, it requires me to kind of think through the way self-interest works in government. So if you’re, say, a government like India, you have persuaded yourself, rightly or wrongly, that, that deploying SRM could really reduce risk to your country, but you are aware of the way other countries might react in a self-interested way. You first of all, almost certainly not go for unilateralism. You build a small coalition because that’s the way in general things happen in international affairs now, because it’s more stable. And that’s true, even if you don’t, in a sense, care about, uh, about non neutral…multilateralism, it’s just pragmatic. And then the question really is how you would go about, let’s imagine this is India, balancing between the hemispheres, and how you would go about doing things that deploying SRM at risk in a way that would or wouldn’t create risk elsewhere.

The obvious kind of thing that comes to mind is that the country would just deploy in its own benefit and like really try and screw other countries and that, that’s certainly a motivation. We see that. There’s lots of ugly governments in the world. But, if it doesn’t cost them anything different to not harm other countries, and if they’re thinking rationally about the actions other countries would take in response to their action, then you might find the… actually what happens is something more even.

Frank Biermann: Listening to David, I’m actually, if I wouldn’t be convinced of the international non-use agreement, I would become it now, I think. To assume that a polycentric governance model, whatever shape you want to imagine it, would be able to govern the deployment of SRM,is just false.

David Keith: So we do have polycentric governance, I don’t love it either, for pretty much everything. And there are all sorts of technologies, uh, including the technology we’re talking about for emissions reduction. So technologies around solar power and batteries also have big inequalities and governance problems. And if you apply the same standard of you have to have global agreement, consensus agreement, you wouldn’t have any mitigation because this agreement as a rule allows hostage taking, allows one party that doesn’t want the consensus to demand some big side payment. So that’s why we don’t really run things with consensus. And that, that statement that in order to, that no technology should kind of go forward, unless we have some universal just governance, I’d like to have a universal just governance, but just to be clear, that would also mean you don’t deploy technologies for cutting emissions, and it also means you don’t deploy lots of other technologies.

Frank Biermann: I think it’s the same point which has been earlier made with penicillin. These are false comparisons. Technologies such as renewable energies, wind energy, it has no planetary impact that is harmful. So in a sense, if I put wind energy in my roof, solar panel on my roof, wind energy in my neighborhood, it has no negative harm for anybody. It has a positive harm. It’s different for SRM. SRM inherently as technology, where one country alone of a certain size and a certain capability can influence the climate for all other people.

David Keith: On the question of governance, of course I agree that SRM raises much harder governance challenges than say does solar power. That’s what I’ve been saying for 20 years, that’s why I work on its governance. But I don’t believe it’s as binary black and white as Frank seems to. And Frank wants to say that the big issue about SRM is it’s deployable unilaterally.

That’s more true than many other technologies, but not in a black and white way. Lots of these other technologies we’ve been talking about have a kind of sense of unilateralism, like say internet, in terms of the kind of underlying architecture and the idea that because of that you can’t do anything, that no governance is possible without global consensus is, is just not the way the world’s worked.

And Frank keeps saying those analogies are not correct, but he’s not offering kind of specific reasons why they’re not correct. The question here is that whether we do work to understand this and to have conversations about how to govern it. I think the underlying reason why research makes sense is that the risks of the technology themselves, which are very real, but the technical risks, the side effect technologies are quantitatively small compared to the benefits. And that’s something that I really wouldn’t have thought a decade ago. And I think the new evidence from climate models really is pretty startling.

First of all, let me say, yes, it’s all research on models. Frank was sort of dismissing it because it was models, but of course, these are exactly the same models and the same 150-year piece of climate science that informs our estimates about the risks of CO2.

The models are not just something we cooked up yesterday. The models are built on observations of the atmosphere, you know, since Tyndall, for a century and a half, and they really are very much the same models as we use to understand other environmental risks like air pollution and climate. And what we find is that if SRM, stratospheric aerosols, say were distributed reasonably uniform, pole North to South, which is technically very doable, that might not happen politically. And if this is done not as a way to get out of emissions cuts, but it’s done as a supplement to emissions cuts, then we find, and that’s true that every model has found, and there are no papers that contradict what I’m about to say, then we find that major climate hazards like temperature, extreme temperature, and changes in water availability tend to be reduced pretty uniformly.

And they give you a sense of the relative risks. There’s now growing evidence in the climate impacts community that temperature is one of the biggest climate risks. Changes in, in mortality from heat. So we’ve used the latest of those heat mortality models in a collaboration with Princeton and some other folks looking at using a model of, of SRM.

And for an SRM deployment that say, reduced temperatures by one degree C, say from 2.5 to 1.5 late this century, you reduce mortality from heat by a million people a year. And that same deployment causes damages, of course, by ozone loss and air pollution. And those numbers are like 10,000 a year. So that means for two kind of pretty important, not that those, not a complete answer, it might be wrong. There’s all sorts of reasons this might be wrong, but, but for two pretty important classes of impacts, heat related mortality and air pollution and ozone risks, the benefits of SRM from these models look kind of a hundred times bigger than the harms.

That might be wrong, but if there’s a reason to take it seriously and a reason that a lot of people in the developing world take it seriously, that’s the reason.

James Lawler: Frank, could you respond to that?

Frank Biermann: Well, as David said, it’s very important to be rational and empirical. And number one is there is no plausible governance model of how this could work. So rationally and empirically, governance remains a huge question in this space. And for the natural science part, I mean, it is models. I mean, that’s what there’s no debate about it. I mean, that’s what David also says. There are models and they’re based, of course, they’re based on the standard climate models. It is an idea that the understanding of the climate system is sufficient, but there is definitely no certainty. There is no evidence so far.

And it’s not possible, the evidence for the impacts of, um, of SRM before it is being deployed for some years at planetary scale. And that’s the only way forward. We don’t have a second planet to try it out. Normally we would have a lab experiment, but we don’t have it. Therefore, people would have to wait and hope and take the risks. And for that, deployment of these technologies without consensus, a deployment without knowing what it is in a situation where other possibilities are on the table, where mitigation is possible, I find extremely risky. I find extremely irrational, and I find it extremely unethical.

David Keith: I did not say that I wanted polycentric governance, and I did not say that I didn’t want consensus.

I said some observations that I think are actually kind of common about the way that climate governance works now. Of course, I would love to see global consensus. As to your really hard question, which is what to do about the threat of moral hazard, that’s a question I wrestled with for a long time. I think I was the first person to use moral hazard in this context more than 20 years ago as a concern for SRM, and it was, as I said, the biggest concern. I don’t have any magic answer about how to solve it. I think this is fundamentally the problem of how we rein in the power of fossil capitalism in slowing down emissions, and that’s actually true, more or less independent of what we know about SRM, but it’s a deep problem and we don’t know how to solve.

It’d be great if we had a solution, but I don’t know what it is. To be clear, I’m not saying that you can’t ever ban technologies and that researchers should be free to do what they want.

I agree with Frank that we have banned and should ban some technologies and, and, and restrict research on them. I think that in general, that applies to things where there’s potential for very large harm and no obvious positive benefit. And I think SRM doesn’t fit that very well. Frank keeps talking about very large harm, but I think it, you know, when you think kind of quantitatively about it using these environmental science methods that we use it to have flaws, I don’t see the harms from SRM as, as being so big, just in terms of what the model said, obviously I can answer this totally outside the models, but that’s true for anything.

And the models are what we have, their understanding of the world. So I don’t see the harms being that big and there’s obviously large benefits that’s been agreed by many different research organizations. So when you’ve got the case of all these big benefits and harms that seem quantitatively small, the case for banning it seems hard compared to say chemical weapons.

James Lawler: Frank, could you give us a closing statement, and then we’ll go to you, David?

Frank Biermann: So, as a final statement, I believe, as I said, that SRM is not the way forward. The plausible governance solutions are not there, and I have not heard in the scientific literature any plausible governance model that be used under the threshold of something which is very unlikely to emerge like a very powerful agency.

I believe there is a huge risk of geopolitical tension and conflict about the development and the deployment of these kind of technologies, ethical implications as well, because many countries will not be involved in decision making. But the final point: is it’s not necessary. It’s a solution that is pushed forward by some members in the scientific communities but I believe the alternative – drastic emissions reductions – is still an option. It’s still possible, here I’m basing myself on the IPCC. And therefore, I think it’s not a necessary step forward to develop these technologies; it’s rather very risky and dangerous.

James Lawler: And David, final statement.

David Keith: I think my final comment is that I agree with many of the risks that Frank sees, and I absolutely agree about the challenges of governance.

I’m just less confident that I know the answer. So Frank, it feels to me is very confident that it’s a false solution, which is a very kind of black and white claim, and that it simply does not work. And I think that’s a stronger claim than you can make based on the evidence. And I think he seems really to be able to say for certain that it’s ungovernable, and I think that that’s just not a claim we’re very good at making.

Humans evolve new ways to govern new technologies as they come up. And my view is that right now we have a debate that is really too much focused in a small in-group, maybe a few small in-groups, of which maybe Frank is on one side and me on another, and I don’t trust any of this.

My guess is that as this debate gets wider, if we have a much wider debate about how to govern these technologies and a much broader research effort, then we’ll get some answers. And maybe the answer will turn out to be that it should never be used and maybe the answer will turn out to be that we should use it. My view is that I don’t know. But that we ought to have a really serious effort both on the research and on, on practical debates about how governance might actually work.

James Lawler: Well, David Keith, Frank Bierman, thank you so much for coming on the show. This was an excellent discussion. Really appreciate it.

Frank Biermann: Thank you, James. Thanks.

David Keith: Thank you. Thanks a lot for doing it, James.

James Lawler: To continue our discussion of the potential risks and benefits of SRM, and include a non-Western perspective on this matter, we invited Dr. Chukwumerije Okereke, a world-renowned scholar on international governance and climate development based in Nigeria.

In March 2023, Dr. Okereke published an op-ed in the New York Times titled “My Continent is Not Your Giant Climate Laboratory,” in which he argues that for the Global South, and particularly the African continent, solar radiation management research is something of a wolf in sheep’s clothing.

He predicts that what is being touted as a solution to climate related heat waves, famine, and drought will likely be controlled by outside interests who are willing to risk delicate weather patterns and ecosystems on which millions of lives on the African continent and in other places depend, in the name of research and to the interests of the Global North.

Dr. Okereke joined me from Nigeria to explain more. Dr. Okereke, welcome. It’s great to have you on today.

Chukwumerije Okereke: Thank you very much.

James Lawler: So I would love to start with a brief introduction. If you wouldn’t mind introducing yourself and give the audience some background on your work and views related to solar radiation management as well.

Chukwumerije Okereke: I am the director of the Center for Climate Change and Development at Alex-Ekwueme Federal University in Nigeria. And I’m also coordinating lead author and lead author of various IPCC reports. And my specialism is, I guess, in three areas. One is climate justice. The other is low-carbon development in Africa, and the third one is corporate strategies for managing climate change. So, the political economy of global climate change. The key thing that propels me is a desire to see a global approach to managing the climate change that also is sensitive to ethical issues, especially the issue of justice, and especially as it relates to the developed and the developing country.

James Lawler: You wrote an influential op-ed in the New York Times earlier this year, and it was published on April 18th, 2023. The title was “My Continent is Not Your Giant Climate Laboratory,” in which you articulated the position that you just reframed for us. But you argued something even stronger than against the deployment of SRM, you argued against SRM even being a topic of discussion or research or presented as an option to African leaders.

Could you restate that argument and explain why do you take that particularly strong position with regard to SRM?

Chukwumerije Okereke: Well, sure. I argued in the op-ed, in the New York Times, on a number of fronts why I think this is a no-go for me, a huge ethical risk. I pointed out that it runs the danger of upsetting local and regional weather patterns, it can disrupt the monsoon cycle, it can impact negatively on regional climate and seasons. Unless you use the whole earth as a laboratory, it is impossible to know whether it will dim anything, let alone judging the possible negative consequences or impacts on ecosystem, on people, and the global climate.

The other point that is related to this is that actually, once you allow this kind of technologies, then you have to deploy it almost in perpetuity. There are suggestions that, of course, if you were to stop deploying these technologies, then you will be unleashing a huge amount of the retained radiation back into the atmosphere, causing what we call a termination shock.

And the consequences on global climate or regional climate systems, such as a monsoon, can only be imagined. Nobody really knows for sure how this is going to affect ecosystems in a negative way, and this will run the danger of affecting millions, if not billions of the livelihood of people. The possibility that the consequences will be borne by those—and of course, it will be white men in, in, in, in sleek suits or their companies—the possibility that Africa will be able to hold them accountable if anything were to go wrong is almost zero. And these men in white suits, they understand, I argue, the danger of this.

Often, they will start by saying, you know, this is risky, we know that this is unproven, we agree that this is speculative, but nonetheless, because you, that is Africa, is bearing the brunt of climate impact, we nonetheless think that it is important to explore these technologies in order to limit the warming and then the climate, uh, consequences of such warming. The question they are not able to answer is why are you not investing your energy in the rapid and massive scaling up or deployment of the proven technologies in Africa? Simple renewable energy technologies, you know, like, you know, solar panels, roof, solar rooftops, wind technologies, geothermal, etc. No one is able to answer this question.

James Lawler: I want to put an argument in front of you, Dr. Okereke, and have you react to it, if you could. With SRM, there, there are various people who are, who are making predictions about what might be possible in terms of global cooling if we were to inject aerosols into the upper atmosphere. And, you know, the results of these efforts suggest that there could be cooling up to a degree, a degree and a half, and that the impact of that could be ultimately to save many millions of lives, whether it’s through improving the output of agricultural activities, whether it’s just reducing death, reducing mortality through the heat related mortality events, etc.

And the argument then is, well, we—it’s a moral obligation at that point to at least study SRM, to understand it better. Because it could be that we’re sitting on this technology that for the price of just a few billion dollars, right, which quite a few countries could do that unilaterally, right? So it’s amoral to say, I’m opposed to even considering this as a technology—it’s an argument along those lines. What is your response when you hear that?

Chukwumerije Okereke: Well, I think what is amoral is holding a known solution to climate change, and energy security, energy assets to a large number of people in developing countries and refusing to scale up that investment ASAP. Now, the total number of renewable energy investments that have gone to Africa, according to IRENA, in the past decade is just about 2 percent of the total investment in renewable energies globally.

Now, the reason why we don’t have a flow of renewable energy investment in Africa is not because of climate constraints. Research is to show that Africa is one of the most favorable places in terms of geography to invest in solar and wind, and yet we have just 2 percent of renewable energy investment going into Africa.

This reminds me of what happened 2020-2021 when the whole world was suffering from COVID, the COVID pandemic, and certain interests in the West, uh, including governments and companies chose to allow or to contemplate African bodies to be littered on the streets of Africa, than to give Africa access to the COVID medicines or drugs.

And this for me is immoral. What is amoral, what is problematic? It is not about spending extra billions of dollars in speculative technologies that could end up exacerbating the inequality and livelihood challenges in Africa. We must press on with doing what we know we can do that have far less risk rather than investing in something that is entirely speculative that could end up exacerbating the problem.

James Lawler: It sounds like the other part of your argument here is if this did proceed, there’s no mechanism for accountability, right?

Chukwumerije Okereke: Exactly. Thank you. I am making precisely the point that we should imagine a situation where, and I hesitate to even grant that, but let’s imagine a situation where we grant that some investment in this speculative technology is able to bring about some level of cooling. And then, this technology resides in the hands of a corporate organization in the U. S, similar to those that had the COVID, you know, drugs. This will unleash a kind of exacerbation of the political economy dynamics that will, that will mean that those who will be able to—assuming is able to, you’re able to, to localize this effect—Africa will not be the country that will get the benefit of this technology. Unless again, they are subjected to another round of loans, debt-trap loans in order to be able to assess this technology.

And this is what we see even with climate change finance. The limited amount of money that is flowing to Africa in the name of climate change finance, most of it is actually tying Africa to another round of long-term loans, that is going to, you know, be a millstone in the neck of future generations of Africa.

So not only is this technology hopelessly speculative, not only will you have to do it in perpetuity in order to avoid termination shock, there is no guarantee that if it works, that there is a way to control it, to, to govern it effectively, and there is no guarantee that, despite all the, the fact that, oh, we want to help Africa, that Africa is going to get the right part of the deal, in terms of the deployment of this technology.

James Lawler: There is a lot of awareness. There’s a lot of interest in the technology, companies are already just unilaterally starting to do it. This has already happened. It seems to me that a world where the temperatures on average are getting hotter and hotter, it’s hard to imagine that there won’t be in the near future, extremely serious heat events that kill a lot of people that precipitate, you know, a rapid deployment of this kind of technology, but unilaterally. You know, and I don’t know if it’s going to be the United States, don’t know if it’s going to be India, you know, some other country, but given the cost that is relatively low, the materials required, which are relatively easily obtained and the massive impacts of extreme heat events and the destructive impacts of this, of the warming that’s happening in the planet.

By what mechanism could we get ahead of it to address the concerns that you have? Is there any way of, of slowing down that train or of, of making sure that the train has the right people driving it? What do we do, given the practical realities of where we are in the world now and where, how warm it’s getting, etc.?

Chukwumerije Okereke: That’s an important question, James, but this is why, I believe, I think that the right thing is to place a moratorium on this. Because, if you don’t do that, what you will have is some kind of rogue, you know, technologists or companies or a group of people, you know, going out and then doing this in a way that is going to be even more harmful.

James Lawler: Well, Dr. Okereke, thank you for your time. Thank you for being so open to talk to us and willing to share your time and your expertise with us.

Chukwumerije Okereke: I’ve enjoyed talking with you guys.

James Lawler: To end this episode on SRM, we wanted to hear from a scientist actively working on researching the impacts of SRM, and a researcher studying the social impacts of SRM’s potential deployment.

For climate physicist Claudia Wieners of Utrecht University, the risks of SRM warrant further research to better understand how we can minimize them and maximize the potential benefits. Arguing against her is Dr. Jennie Stephens, Professor of Sustainability Science and Policy at Northeastern University and Radcliffe-Salata Climate Justice Fellow at Harvard University.

Professor Stephens argues that even the act of researching SRM poses threats to nations in the global south, indigenous groups and other marginalized communities.

Claudia Weiners and Jennie Stephens, welcome to Climate Now. It’s great to have you both on today.

Jennie Stephens: It’s great to be here.

Claudia Wieners: Thank you very much for inviting us.

James Lawler: So I’d like to start with introductions. Claudia, why don’t we start with you? If you could please introduce yourself, your affiliation, and give the audience a little bit of background on your work in the SRM space.

Claudia Wieners: Sure. So my name is Claudia Wieners. I work at Utrecht University in the Netherlands as an Assistant Professor in earth system modeling. So basically, a climate physicist running big climate models. And my main topic of interest is solar radiation management or SRM, in particular an SRM method called stratospheric aerosol injection, which is about basically imitating the effect of volcanic eruptions to cool down the earth. And one of the questions that particularly interests me right now is the ability of SRM to interact with climate tipping points. So can, for example, SRM prevent the death of the Gulf Stream or could it even make it worse?

James Lawler: Great. And we’ll get into more of that soon. Dr. Stephens, would you mind introducing yourself and giving the same context?

Jennie Stephens: Sure. I’m Jennie Stephens. I’m a climate justice scholar, activist, and a feminist who brings a social justice, decolonial, anti-racist, economic justice perspective to my work.

So, I have a background in environmental science and engineering, but I’m currently a professor of sustainability science and policy at Northeastern University in Boston. But throughout my career, I’ve been focused more on policy and social justice because it’s increasingly clear to me that the technology-focused approach to thinking about the climate crisis has led us to continued delay and denial of the larger social and economic challenges that are so desperately needed.

So I really approach the climate crisis as a symptom of a much larger problem. I increasingly am focused in my work on that larger problem. So in my academic work and my advocacy, I focus on the need for transformative society-wide policies, including fossil fuel phase out and investing in vulnerable communities and constraining the continued concentration of wealth and power.

James Lawler: Now, Dr. Wieners, earlier this year, you cosigned an op-ed in the journal Oxford Open Climate Change, where you and a colleague made the case that thorough and critical research on SRM is a safer path than willfully neglecting it. And so, that letter is connected to a website, which people can go to call-for-balance.com, where you make clear that while you’re advocating for SRM research, you are not advocating for the eventual use of SRM, and I wonder if you could sort of make the distinction clear: you’re pro-research, you’re not necessarily pro-implementation. Why is researching SRM so important in your view?

Claudia Wieners: Yeah, so maybe a bit as a background for why we wrote that letter. We were quite annoyed, if I may say so, that many, not all, but many critics of SRM have very unbalanced arguments, in our view, pointing to SRM being risky, but ignoring the fact that rejecting SRM is also risky.

So, I mean, unfortunately, humanity has worked itself into a very nasty corner. If we want to limit global warming to 1.5 degrees, we would need stringent negative emissions, taking CO2 out of the atmosphere, and we don’t yet know how to do that, if we can do that at the required speed. And even if we are as successful as the most optimistic scenario in the recent IPCC report, we could still be unlucky with climate sensitivity, so how strongly the climate reacts to greenhouse gasses. Even if we really do our very best now to reduce CO2, we may still end up as a very bad climate state. And so I think because all these three possibilities, we don’t manage negative emissions, climate sensitivity is high or 1.5 degrees is not enough, every one of them has a significant probability of occurring. We cannot say that we don’t need SRM. But if we may think we may need it, we should better understand it before someone becomes so desperate as to say, well, we are fucked, we should just do it.

So I’m not advocating to do it, but I think we should understand better whether or in which context it may be a good idea or not.

James Lawler: Dr. Stephens, in a 2020 paper published in the journal Global Sustainability, you and a co-author stated that solar, I quote, “Solar geoengineering research advances an extreme expert elite technocratic intervention into the global climate system that would serve to further concentrate contemporary forms of political and economic power, and that it is unethical geoengineering research.”

Would solar radiation management research, in your view, be more palatable if it was researched by a more diverse group of scientists and governments? Why advocate for no research at all, given sort of the probability that this will be used and, you know, the desirability of at least having an understanding of the potential effects.

Jennie Stephens: Yeah, so this is- has been a very fringe idea for a long time. And only recently with some very strong advocacy from scientists who had support from some tech billionaires and other philanthropists has this become more mainstream. So it really is a fringe idea that a lot of people have a lot of deep, deep concerns about.

And so, we know from science and technology studies, the more something is researched, the more likely it is to be deployed. It gets legitimized in the public sphere, in public policy, in public discourse. It has an impact on deciding and prioritizing other climate strategies.

So that legitimization and distraction I think are really dangerous and the other thing that I want to acknowledge is that scientists have a very limited way of thinking about the technologies they work on. They aren’t thinking about the big geopolitical implications or all of the complexities of what could happen once their technology is out in the world. And so I, I think in this debate, we’ve been giving too much power and influence to the scientists to set the agenda and we need again, to zoom out and think, okay, what should we be prioritizing in our attempt to address these multiple crises that the, that the climate crisis represents, uh, you know, big part and a big immediate threat that we have. And we need to look for broader wisdom about, you know, humanity, right?

And, and I think we’ve given too much power to scientific knowledge and not enough power and influence to, for example, indigenous knowledge, feminist perspectives, more holistic and integrated ways of thinking about how we’re all interconnected, how humans are interconnected with the non-human world, how we prioritize this kind of, those interconnections and the power dynamics of having control over creating one more mechanism by which some powerful interests could manipulate and control the whole earth system to me just seems dangerous and I think it seems very dangerous to a lot of people, and I think that’s why I don’t want my tax dollars going to support this idea.

That’s why I don’t think we should be doing research on it. I think it legitimizes it, we already have examples of rogue actors experimenting with it. So we, you know, I think we should be focusing on trying to restrict and delegitimize this as soon as possible.

James Lawler: So I wonder if I could ask you sort of a somewhat provocative question, which would be: let’s say that the research does happen into SRM, and we were to find that in fact, you know, by the careful deployment of this technology, we could limit global warming to under one point, whatever it is, however much 1.1, whatever it is, such that, you know, millions of people that otherwise would have died because of heat effects or reduction in crop yields, etc, will not die if we do it right. And, and we find that on a cost benefit basis, our best projections show that this is a sort of a net positive in terms of life saved, in terms of ecosystem saved, in terms of those benefits.

Wouldn’t, wouldn’t it be good for us to know that?

Jennie Stephens: So I think the, that’s the scenario and the vision and imagination that a lot of the advocates for solar geoengineering research are projecting, right? And they have very good intentions, and I respect that. The fundamental difference and the fundamental challenge with solar geoengineering is that we know that there’s no way that it will be a benefit for everyone.

There could be disruptions in the monsoon season, for example, right? There could be some, and there will be, I mean, there’s no way to do it, as far as I understand, without having disruptions in the climatic patterns, right? And that’s the whole point, right? Is to change some of the basic climatic realities.

So, what I see as the real risk is that there will be sacrifice zones, right? There’ll be specific areas depending on who’s controlling it, it’ll be optimized for certain regions of the world and other regions of the world will, will be worse off. So that it would be a net benefit for everyone, I think is a nice imaginary, but I don’t think that is realistic based on how complicated the Earth system is, how many vulnerable people we have in, on the planet already. Um, and given the power dynamics of geopolitics, it just does not seem realistic.

James Lawler: Dr. Wieners, what is your response to that?

Claudia Wieners: I don’t say that there isn’t a risk that some people will benefit more or less than others, but I also think that it’s quite possible, not at all certain, but quite possible, that certain SRM scenarios are quite broadly beneficial for nearly everybody.

So, for example, there’s been preliminary research by Irvine et al. who found that if you reduce global warming, so let’s say you half global warming by use of SRM, this would drive import climate variables much closer to the preindustrial state than having the same amount of CO2 without doing the SRM.

So it’s not like half of the regions are better off and half of the regions are worse off. There could still be room for conflict. Well, you know, maybe this region wants 1.5 degree amount of cooling and this region wants 1.1, and you can have conflict on that and power dynamics and everything. But I think it’s quite conceivable that certain partial, modest amounts of SRM benefit nearly everybody. At least it’s not certain that it will automatically lead to big sacrifices. Who are we here sitting in rich Northern countries to say to global South countries, you cannot have SRM research? I mean, often it is argued like in the name of the global poor, we should stop this research, but you can equally turn this argument around in the name of low-lying Pacific islands, who are we to say we cannot do SRM research, even if for them, it may be the difference between drowning and not drowning? So we should really always look at both sides of the risk balance.

James Lawler: So Claudia, what do you make of this issue that once we start down the road, right, towards a goal, right, of studying a thing, understanding a thing, especially when the thing is very likely to confer some benefit on some groups, right, which I think everyone is sort of acknowledging that that’s the case here with SRM, like even if we don’t fully understand it, or even if we’re wrong, we think it will right, confer benefit and so we would do it. What do you make of that slippery slope argument and, you know, by studying it, you’re kind of creating a reality or a sense of inevitability that this will be done and so we shouldn’t move forward because of that?

Claudia Wieners: Yeah. Okay. So first, I mean, that’s a justified concern to some extent, but also one counter argument that should also be considered is that research can also reveal that a certain SRM technique is not a good idea. So as an equivalent look at ocean iron fertilization, which is about removing CO2 from the atmosphere by basically fertilizing algae to take up CO2.

James Lawler: So this is, this is scattering iron particles over the ocean surface to stimulate algae growth to then draw down CO2.

Claudia Wieners: Yes, that’s what I mean. So, this technique was hyped for a while and then further research showed that it’s very uncertain and potentially not working and it is now more or less off the table because the research was done. So research can also eliminate bad ideas by showing that they don’t work.

And also, I mean, Frank Biermann, one of the opponents of SRM research, he wrote some years ago that “the demon must not be let out of the bottle.” But the demon is out of the bottle already, and we should acknowledge that. So there is already enough knowledge or ideas about SRM to tempt somebody in case of a perceived climate emergency to just say “we are so desperate we’ll do it.”

So in my view, it’s a better way to go forward to check what may work and especially what does not work and take the time to have global deliberations so that people can get used to have the idea, understand what their priorities are, understand what they really don’t want so that we are not  surprised by someone saying in despair, “we now do that and if you don’t like it, you may throw a nuclear bomb on you.” It’s too late to put the demon back into the bottle.

James Lawler: Right. So Dr. Stephens, what, what do you make of that?

Jennie Stephens: I think that what we need to focus on is not research, but action to protect against those inevitable, not surprising scenarios of it being deployed. And so I think we need to focus on paying attention to what are those risks of deployment and how do we reduce the risks of deployment based on what’s already known.

I don’t believe that there’s more scientific research that we can do that is going to help us with the governance challenge and the deployment challenges, because those challenges are not about whether or not it will work, right? They’re about these distributive social, political, economic challenges that are not about the physical science. I mean, many of our listeners may have recently seen the Oppenheimer movie, for example, right? That showcased how the scientists developing the technology were aware of the risks, and then at the end, they, like, wanted to hope that it was going to be used or not used in a way that was net benefit, yet it was out of their control, right? The bomb went off and the team is irrelevant at that point.

So I think scientists also need to recognize that they, scientists and the researchers, do not have control over what happens after they’ve done the research.

James Lawler: I think Dr. Stephens made a good point, Claudia, that essentially the scientists who may be saying that, you know, don’t have control, right?

It’s not, it’s not within the community that might be advocating for SRM research to control whether countries use it as a way to avoid reducing emissions. And so by achieving this legitimizing effect, you’re kind of creating a path for countries that really don’t want to reduce emissions by giving them an out.

And that’s just human nature, you know, why change, why do something that is more expensive, more painful, i.e., reduce emissions if we can just inject a bunch of sulfur into the atmosphere?

Claudia Wieners: Yeah. I mean, that’s definitely a risk of SRM research, though I, I’m not sure how much worse it will be seeing that ideas already out there, but I would say this is a very legitimate concern.

I don’t say SRM is great, it’s risky. It’s just that rejecting SRM is also risky in my view. And I think we have just about like tipped the balance for SRM research, at least that’s what I believe, is better than rejecting the research. But this doesn’t mean that, that we shouldn’t be careful about it. And I also, for example, I mean, often people like me are portrayed as SRM advocates, which is not quite true because I’m an SRM research advocate, not an SRM advocate.

But I think many of us would agree that there should be governance and control to limit potential bad effects, for example, political ones. So, for example, many people who I interact with say, well, and I agree to that, say, “well, it would be a good thing to have, for example, a temporary moratorium on large scale experiments and deployment, at least for a while.”

Jennie Stephens: So I’m not optimistic about global governance on SRM, that’s one of the reasons I’m against legitimizing this as a, an approach, because I don’t see, given the rise of authoritarian leaders, nationalism and our governance challenges globally, I’m, I’m not. optimistic. I think it’s fine to speculate and imagine what could be, like, oh, we should, we should do this or should do that, restrict this, restrict that. But again, I think there’s not strong evidence to suggest that, that it will be easy to get everyone to agree, right? Like on any of that. So, so I think governance is a fundamental challenge with the whole idea. I guess I also want to return to a larger point about power and control that is related to the governance question.

What I see happening in the world right now is a global solidarity movement among vulnerable people around the world, right? And there’s power and things are changing, and I don’t give up and assume, you know, there isn’t going to be change in our governance structures and or in our economic systems and a redistribution of wealth. And this is what is so frustrating for me, is that we assume that we can’t change what we’re doing as human beings, but we want to manipulate how the earth’s systems work. And it’s like, that is just scary. And so like, what I encourage people to do is to focus on social change, political change, economic change so that we can address, and we need healing and, and, and reinvestment in what matters.

And, and these, this, these ideas of promoting a technical fix, oh, we might need it sometimes, so therefore we have to invest money in it. And like, I think it’s distraction from what we need to be doing and who we need to be listening to in terms of vulnerable people, indigenous knowledge, science. The science of Western science isn’t the be all end all, right? There’s so much else that we should be integrating into our, our governance structures and I think that’s where I just like to redirect the conversation as much as possible because it’s almost a delay and distraction tactic, right? The people who don’t want change are promoting solar geoengineering.

Claudia Wieners: No, this is not true.

Jennie Stephens: There are some, I know some.

Claudia Wieners: There are some, I mean, but it’s not everybody who promotes SRM research is against global change. I mean, solidarity and redistribution of power is great, but no amount of solidation and redistribution of power will reduce, per se, the CO2, which is already in the atmosphere. So maybe we just need both.

James Lawler: Jennie, what do you think about that?

Jennie Stephens: I think the risks are too big. I think the risks of legitimizing, mainstreaming a technology that gives so much control and power and manipulative power to a powerful interest and the rest of us are just pawns, you know, there’s no way to do it democratically and/or justly.

Claudia Wieners: How can you claim that? And then also you claim that you cannot do SRM democratically, which is I mean not a fundamental law of nature like gravity, so you can’t just say that and then also you say you want to prevent rogue action? So, please could you say me how you concretely want to prevent rogue action?

Jennie Stephens: I mean, I think some regulatory framework.

Claudia Wieners: How would the framework look like? You’re the governance and social science expert, not me. So how would you set up a regulatory framework that prevents rogue action on SRM?

Jennie Stephens: Well, for me, it would be part of a larger regulatory governance shift. We have too much powerful interests deciding what we invest in, including these kinds of technologies. So, I mean, that needs to change.

Claudia Wieners: Right, but if, suppose that then the shifts that you think are necessary to prevent rogue action are possible, so have more solidary framework somehow, wouldn’t in such a framework, that, that prioritizes solidarity, wouldn’t such a framework also probably have the wisdom to use SRM or at least consider SRM in a wise way, such as to benefit? I mean, if you already are in a framework of global solidarity, then we probably will also have the wisdom to use SRM in a reasonably fair balanced way.

So how, somehow you, you seem to, to argue that SRM cannot be done democratically, but climate change can be solved democratically, and the solidarity framework is coming. I, I see some inconsistency here.

Jennie Stephens: Well, my perspective is formed by who has been advocating for solar geoengineering and where their funding comes from and the lack of legitimate consideration of other voices, feminist voices, indigenous voices who express concerns.

Claudia Wieners: I don’t think so. I mean, for example, there’s a Degrees Initiative that really tries to help people from hitherto, let’s say, less well equipped countries like Global South countries to set up their own research to engage in capacity building, to allow researchers from these countries to really form an informed opinion.

And, well, as far as I know, this is a pretty unique attempt from at least part of the SRM research community to really engage with these countries and help them to come up to speed, not prescribing that they should advocate SRM, but enable them to figure out what SRM would do in their country, such that if ever there comes a global debate on whether SRM should be done or not, these countries also have their own local experts who can then defend their country’s interests.

So wouldn’t it be much better to do this capacity building and really allow a broad discussion than having some guys in white countries or Global North countries or whatever you want to call it to say this is immoral, we shouldn’t do it?

James Lawler: Dr. Stephens, what you’ve been pointing to, this idea that once we create the knowledge, right, we set a path, we set sort of ourselves on this inevitable path to some degree, right? That’s this one of the things that you’ve mentioned. And this is dangerous because of where that path might lead.

I’m wondering about how you square that with other sort of avenues of scientific inquiry that have created huge value for the world. Right, like, let’s say, you know, medical science that has taught us about cells or genetics, right. Things that have allowed us to cure disease that indigenous people benefit from just as much as people in the wealthy North, right, Global North. Like there is there is precedent to science achieving great benefit to all of humanity, even when it’s delving into sort of, you know, things that could be used for evil, right?

For we, we, we can also use this information we have about genetics for, you know, weapons of mass destruction, for example, but I think by and large, many people would agree, the science that we’ve developed along those lines has been a great benefit. Why wouldn’t SRM be one of those examples?

Jennie Stephens: So the planet and humanity is in crises, right? Not just the climate crisis, but so many polycrises of insecurity and precarity and vulnerability and this concentration of wealth and power. So it is a time where it’s particularly dangerous to be promoting technologies or advancing technologies that, again, create one more mechanism, as I said before, that allow the powerful to have control over everyone else.

So I just wish all the billionaires and philanthropists who are supporting solar geoengineering research, all the scientists working on solar geoengineering, shifted gears and focused on fossil fuel phase out and reimagining how to heal the Earth, right? There’s ecological destruction so much deeper than the climate crisis and the temperature of the Earth.

Biodiversity loss, water and air pollution, human health being degraded by plastics in our bodies. The list goes on and on, and I mean, that’s what we need to be focusing on. How can we re-imagine humanity so that we are not continuing down this path of destruction? And I don’t see SRM helping us, and I see it distracting us from making changes off that path.

James Lawler: Well, thank you both for such an insightful and honest discussion.

Before we close, I would like to once again thank all of our participants. SRM is a complex and important topic which may or may not have an enormous impact on our lives in the near future. We hope that this episode has been useful in helping you understand some of the complexities surrounding the issue.

If you’d like to learn more about our guests and their research, we’ve linked to their work in our episode description on our website climatenow.com. As always, a fully sourced transcript is available as well. And if you’d like to get in touch with us, you can email us at contact at climate now.com. We love to hear from our listeners, and we hope you’ll join us for our next conversation. Thank you.

Climate Now is made possible in part by our science partners like the Livermore Lab Foundation. The Livermore Lab Foundation supports climate research and carbon cleanup initiatives at the Lawrence Livermore [00:12:00] National Lab, which is a Department of Energy applied science and research facility. More information on the Foundation’s climate work can be found at livermorelabfoundation.org.