A Briefing and Discussion on Solar Geoengineering: Science, Ethics, and Governance

Selected slides are included in the transcript. For a PDF of the full powerpoint of 81 slides, click here. For a list of further reading recommended by speakers, click here.

JANOS PASZTOR: Good morning, good afternoon, good evening, colleagues, in whatever time zone you are in. Welcome to the webinar discussion on Solar Geoengineering: Science, Ethics, and Governance. [Slide 01] My name is Janos Pasztor, and I will be your co-host together with Simon Nicholson, who is also on the screen, and he will say a few words in a moment. Thank you all very much for joining us for this webinar. We have actually 75 people registered, not all of whom are connected yet. We will see how well they are able to connect. We have a pretty exciting program for the next two-and-a-half hours. I will not go into the details; I presume you have seen them on the web, and you have in front of you the agenda. Just a few words about why we are having this webinar: On our side, the Carnegie Climate Geoengineering Governance Initiative (C2G2) is committed to exploring governance of climate geoengineering in an impartial manner. We are going to be exploring governance challenges and options. Part of all of that is, of course, having dialogues about the subject like the one we're going to have today. In addition to that, we also have had a number of discussions with colleagues in different institutions about these governance issues, and it was felt that, instead of simply doing many one-to-one discussions, it would be useful to do a webinar where a number of different people could connect at the same time. So that is one of the reasons why we went ahead with the webinar. There are also a number of inter-governmental and non-governmental organizations we have been in touch with that are either considering what to do in relation to governance of climate engineering or increasing their existing work, but they also welcome the idea of doing something like that. There are also other interesting developments, such as, of course, the Intergovernmental Panel on Climate Change (IPCC) is preparing for a special report on 1.5 °C. It is also preparing for the Sixth Assessment Report, and it is useful for them to have this kind of discussion. Finally, another interesting development is that some are going ahead and shifting from in-laboratory to in-situ experiments, and there again some issues arise that make it useful to have this kind of a discussion. Our webinar is going to be in two parts because, even though we wanted to focus on the governance, we need to look at the science basis to make sure we are all on the same page, so we'll start with that. That part will be co-hosted and facilitated by Simon. In the second part we'll look at the issues of ethics, intergenerational issues, and governance, which I will then facilitate on behalf of the C2G2. We have a list of really excellent panelists. They have published widely on these issues, and they will continue to publish in the future on these issues, so we hope that they will be able to help everybody with some useful information. With that, I would just like to pass the mic over to Simon, who will say a few words, and then get us going. Thank you. SIMON NICHOLSON: Thanks, Janos. [Slide 02] Thanks, Janos, to you and your team for organizing this with the help of Michael and folks on my side. My name, again, is Simon Nicholson. I'm co-director with my colleague Will Burns of the Forum for Climate Engineering Assessment (FCEA) at American University in Washington, DC. We're a group that was set up back in 2013 in an effort to build a more robust and inclusive conversation around so-called "climate engineering technologies." You will hear today about the scientific basis of the climate engineering conversation, with a focus particularly on what is known as "solar radiation management" [SRM] or "albedo modification" or "solar geoengineering"—they are different names for the same bucket of technological response options. You should know about the work of the Forum that we don't take a position on whether or not particular technological pathways are good or bad ideas. We are a process-oriented group that works to make sure that the conversation includes a broad array of voices. [Slide 03] Just to flesh out a little of what Janos said about the purpose of today and how the day is going to be organized, again, we're looking at two different types of things across the webinar. First we'll look at the state of scientific understanding, so with the guests that we have we'll explore the sorts of questions that have been asked, and to this point answered, when it comes to climate engineering, and in particular solar radiation management. We will also hear some thoughts about the questions that should be on the table now if the research agenda is to take hold and to move forward. Then, with Janos' guidance, we'll have a conversation about current thinking on the governance landscape. In terms of the context and frame, we can't talk about so-called "solar radiation management" or albedo modification absent consideration of the rest of the climate action agenda. So one thing that we're looking to do through conversations like this is to make sure that solar radiation management isn't seen as some kind of last-gasp effort that the world might reach for if it proves more difficult than one might imagine to stop moving beyond dangerous climate thresholds. Solar radiation management, as we will hear, is at best a small component of a broad climate response agenda, and it can only be really meaningfully considered in that way. Another piece of context is the more ambitious 1.5 °C target that came out of the Paris negotiations. When we start to think about the carbon budget and the time that we have left for global energy transformation and the sorts of societal changes that are required to stop passing through those dangerous climate thresholds, then it's demanding consideration of things that up until this point the world has not wanted to consider. This is not an argument for solar radiation management; it's an argument for careful consideration by sober thought leaders on this topic. Finally, as we wrap up the conversation today, we'll talk about further resources and some ideas about continuing what is going to be a more and more important conversation through time. [Slide 04] Let me introduce very briefly the three speakers that we have in this first segment on the physical science basis of solar radiation management. Our first speaker is Doug MacMartin, who has an affiliation with Cornell University and California Institute of Technology. We will hear from Doug about what solar geoengineering looks like in the context of this broader climate change response agenda. [Slide 05] Our next speaker is Tom Ackerman, who is at the University of Washington and one of the leaders of the Marine Cloud Brightening Project. Tom will build on Doug's presentation to talk about what he sees as realistic scenarios for the potential use of solar climate engineering, and will start to set the stage for us about not just the scientific but also ethical and other dilemmas that come along with consideration of these pathways. [Slide 06] And then finally, we have Pablo Suarez, who is associate director for research and innovation at the Red Cross/Red Crescent Climate Centre. Pablo's work reaches into the humanitarian space, and he will help us think about connections to the humanitarian dimensions of consideration of solar geoengineering. With that, welcome, everybody. Thank you for joining us. Let me pass it across to Doug for our first presentation. DOUGLAS MacMARTIN: Thank you, Simon. [Slide 7] I'm going to talk a little bit about the context for thinking about geoengineering, what it is, what role it might play in managing climate risks, and a little bit about what we know and don't know about these ideas.

Slide 08

I'll start with the overall context picture. It is certainly absolutely essential to cut our carbon emissions, and nothing that any of us say today changes that. The context for thinking about these ideas is simply that it's not clear that we are going to be able to cut our emissions fast enough to avoid significant climate change.

If you look at the context for the agreements that have been made under the Paris Agreement for cutting carbon emissions, right now those add up to something more like 3 °C of warming by the end of the century compared to the target of 1.5 °C. If you go on to the next piece of the puzzle here, there is a set of technologies referred to as "carbon dioxide removal" (CDR) or "negative emissions." These are already buried into all of the IPCC scenarios, typically in the form of bioenergy with carbon capture and storage—you basically grow plants, burn them in a power plant, suck the CO2 out of the flue gas, and store that underground somewhere.

There is a set of technologies in that area. In principle, you can pull the carbon directly out of the air chemically and store it underground—that is likely to be extremely expensive—and a few things such as planting more trees; better management of soils. So there are a number of ideas in this area. They tend to be either slow, expensive, or some combination thereof, but can play a critical role in the long-term solution of the problem. The other thing I want to say about the CO2 removal upfront is that it gets at the real problem of pulling greenhouse gases out of the atmosphere. From a purely climate perspective, that is low-risk, but there are potential issues with individual technologies. For example, with the bioenergy part there is competition with land use, and with the carbon capture and storage part of that the question of safe long-term storage of very large amounts of CO2. Given that backdrop, the more uncertain and challenging one to think about is the solar geoengineering or the solar radiation management.

I think the question—it is certainly not clear—is whether with solar geoengineering there is a plausible role for reducing climate risks, so basically whether following that blue pathway is less risky than following the green pathway.

Two main ideas that people have talked about here is putting aerosols into the stratosphere. That basically mimics a large volcanic eruption. We know with absolute certainty that you could cool the planet to some extent; the aerosols would reflect sunlight. The other idea is marine cloud brightening; spraying saltwater into low marine boundary-layer clouds to make them brighter and reflect more sunlight. And then there are a handful of other ideas as well.

The key features of solar geoengineering are: (1) it's fast, unlike CO2 removal; and (2) it does not reverse all of the changes of climate change.

Slide 09

I think a lot of people, the first time they hear about solar geoengineering, this is the picture that is in their head. They immediately leap to the idea that this is being proposed as an alternative to cutting emissions. That is a terrible idea, I think everybody would agree, for lots and lots of reasons. If nothing else, it would require—we're not even sure that we could get a forcing high enough to offset all of the carbon if we didn't cut emissions, and it requires a practically indefinite commitment, so tens of thousands of years if you don't pull the CO2 out. Just because we don't want this scenario, doesn't mean we shouldn't be thinking about whether it makes sense to include solar geoengineering for limiting damages as part of an overshoot.

Slide 10

The reason I wanted to put this slide up is just to be a little bit more quantitative. Both of those last slides were totally qualitative. I put together a scenario here that peaks at about 2.6 °C of warming. That is slightly more aggressive carbon emission reduction than we're currently on trajectory for, and a level of CO2 removal that is actually probably a bit unrealistic, but even with that, if you used solar geoengineering to hold the temperature constant at 1.5 °C, you'd be looking at a couple of hundred years' commitment. So there is no real deployment scenario here that is measured in decades; these are measured in centuries.

Slide 11

I'm just going to say very briefly it's nice to draw these plots with a straight line on the temperature at 1.5 °C, but not all the variables are going to respond the same way. Tom is going to say a little bit more about this, but for example, the precipitation is overcompensated, so you reduce precipitation relative to a 1.5 °C world that you achieved with mitigation. Then other things like ocean acidification, solar geoengineering doesn't help you, so that is another reason why the emissions cuts are essential.

Slide 12

Here is just one slide showing projections of models. These are scaled to that scenario, so saying, "If you do large emission reductions that get you to 2.6 °C, and then you use geoengineering to bring you down to 1.5 °C," the end-of-century warming and precipitation are in the top row without geoengineering, and with geoengineering in the bottom row. The middle row is just for comparison, if you were looking at a point in the century where the temperatures are roughly the same as the geoengineered case. In the bottom two rows, the temperature and precipitation there are not the same, but either case is much closer to each other than either of them is to the non-geoengineered world. This is a median over 12 models. It is just solar reduction in these models; this is not actually simulating stratospheric aerosols or marine cloud brightening. But this is basically the argument for saying that it's plausible that solar geoengineering could reduce climate risks for just about everybody. You shouldn't walk away assuming it will; just that the model results today don't show catastrophic effects. [Slide 13 (skipped), Slide 14] This is a long list of all sorts of things that we don't know about stratospheric aerosol geoengineering in particular. This is probably the best-understood approach, and there is still quite a long list of things that we don't know. The reason that I wanted to put this up is simply to recognize that this is not a near-term thing; this is going to take a lot of research. I will wrap up and pass it over to Tom in a minute.

[Slide 15] I didn't say a lot about how difficult it is to cut the carbon emissions to reach a 2 °C target or a 1.5 °C target, but just to reiterate what Simon said earlier, this is simply the context to think about solar geoengineering; it is not an argument that we have to do solar geoengineering.

The sentence toward the bottom is probably the strongest statement that you could make: "Based on the modeling results to date, it is plausible that an additional and limited deployment of solar geoengineering could reduce aggregate climate risks." We don't know enough today to make informed decisions about that. In thinking about it, one has to think not just about the climate risks but also all of the issues in terms of ethics and governance, etc. I will pass that over to Tom.

SIMON NICHOLSON: Thanks, Dave. Okay. Let's turn to Tom. THOMAS ACKERMAN: [Slide 16] Thank you, Janos, and thank you, Simon, for the opportunity to speak this morning. Thank you, Doug, for the nice introduction. [Slide 17] Doug gave a very nice introduction. There are actually two ways in which we're thinking it might be possible to modify the solar radiation reaching the Earth. One of them is stratospheric aerosol injection, which mimics in some sense what we know happens following volcanic eruptions; the other is marine cloud brightening. You can see an image on the right-hand side that has linear features in the cloud deck. Those linear features are the result of ships passing underneath the clouds, brightening them. [Slide 18] My number one rule is to reemphasize something that Doug said: If you start solar climate engineering without any program to stabilize CO2 concentration in the atmosphere, you're committed to using solar climate engineering forever or have a climate disaster on your hands. No stabilization means that you have to increase solar climate engineering each year to offset the increase in CO2. We don't know if you can do that, whether we can provide enough forcing. In addition, if you stop doing it any point, the climate will warm rapidly in about a decade back to what the value would have been if it had never started, and that would be much more shocking to the system than allowing it to warm gradually. I also think it is ethically wrong to commit succeeding generations to a process that they cannot stop. [Slide 19] What I'd like to do here is talk about a specific climate model simulation, or a set of them, that describe the sort of situation that Doug was talking about. We're going to assume a scenario—in fact, we're going to assume two scenarios—of increasing CO2. In one, CO2 increases with time and then stabilizes at a relatively high concentration. Then we are going to increase CO2, allow for a brief stabilization period, and then remove it. We are going to combine this second scenario with solar dimming as a surrogate for solar climate engineering. What I mean by that is in the model we turn down the amount of solar radiation reaching the planet, which obviously is not something we can do, but is a rough simulation of what we're trying to do with these other methods. And we choose a combination of those two forcings to maintain a roughly constant global forcing, and therefore roughly constant global average temperature, and an intermediate temperature between no warming and a large warming.

Slide 20

This is just a graph of the forcing CO2. Forcings are in blue. When I say "forcing," the idea is that CO2 increasing concentrations as shown by the bright blue line are increasing and therefore trying to warm the planet. The green curves down below are reductions in solar radiation; a strong case and a weak case. The orange and red lines provide the combination forcings for these two scenarios where we combine both CO2 and the solar reduction.

Slide 21

This is a little bit of a busy diagram. On the bottom are 200 years of simulations starting in the year 2000. On the vertical axis are the changes in temperature based on a comparison with the 30-year average from 1970 to 1999 in our model. You can see that in the blue curve, which is the one where we add CO2, it goes up relatively rapidly and then the rate of change slows down but continues to warm. This is what we refer to in the literature as the "commitment," the fact that even if we stop adding CO2 there is some time left in the system that it will continue to warm. I want to draw your attention to the brown curve and the black curve at the bottom. The black curve is the commitment from 2000. It is simply allowing the model to warm with this commitment. The brown curve shows the temperature that we get by adding a CO2 forcing and a strong solar dimming. You can see these two curves track along very nicely, which means, simply put, that we can in fact pick a solar forcing, at least in our model, that will compensate for CO2. I could make a long argument about why this should actually work in the real world as well.

Slide 22

That looks very good, but this is a slide that should be troublesome to us all. This is global mean precipitation. If you look again at the bright blue curve where we simply add the CO2, you can see that the global precipitation, which is what is plotted on the vertical axis, increases with time. The global precipitation increases with time because the atmosphere is warmer, and that accelerates the hydrologic cycle. If you look at the black curve you can see—this is the one with constant 2000 concentration—that the precipitation remains relatively constant. It goes up a little bit as the atmosphere warms slightly. The interesting curve is the brown curve, which, if you remember, was the curve where we applied the strong solar forcing. The result of that is that we've reduced the hydrologic cycle. What happens is that when you turn down the amount of solar radiation reaching the planet for whatever reason, you reduce the solar radiation reaching the ocean, and therefore you reduce the amount of evaporation, and if you reduce the amount of the evaporation, you reduce the precipitation. What we can see from these two brief looks at our model runs is that you get to pick a climate with a certain temperature and a certain global precipitation rate, but you can't get both of those to look like the current climate.

Slide 23

Another point I want to make is maybe a little confusing in this slide. This is a plot of 20 years of the global surface temperature from three model runs. The first one, the blue one, is the one with accelerating CO2 concentration. The gold color or yellow color is the one where we've matched the two forcings to try to maintain the temperature, and the red one is an intermediate scenario where we've allowed the temperature to warm between the other two cases. If you squint at this plot—the dotted lines, by the way, are fits to the 20 years of data—after about 10-15 years you can see these curves diverge. But prior to 10 years, it's very difficult to tell the difference between the blue curve, the red curve, or the gold curve. If I didn't put the lines in there, you would be hard-pressed to know which scenario I was talking about. The point here is that if we start adding forcing—say, stratospheric aerosol injections or brightening marine clouds—there is probably a 10-to-15-year period before we will know how we have affected the climate system simply because of the natural variability in the climate system.

Slide 24

This slide is meant to illustrate another issue. There are the process studies which are down in the corner of this space-and-time diagram. There are things called the albedo response test; there are climate response tests in which we try to change temperature or precipitation; and then there is deployment. Right now, as Doug said, there are lots of questions that we have. A sort of unreasonable estimate of how fast we might be able to answer those questions in terms of how these processes worked is something on the order of 10 years. We would then go to larger-scale tests, and those tests are probably going to take us another 10 years to figure out how to do them and to examine the results. So overall, we're looking at something like 15-to-20 years before we could even think about deployment and understanding what we're doing. Often people talk about the idea that they could do solar geoengineering in a year or two. Well, you might be able to, but not in a responsible manner.

[Slide 25] To wrap up, the lessons we've learned so far in our research that I want to emphasize for you is that we can use solar climate engineering to reduce climate warming while waiting for CO2 removal. I want to emphasize, like Doug did, that CO2 removal must take place. Solar climate engineering impacts both the hydrologic cycle and the global surface temperature, so you enter into this question of who gets to pick the right climate. Even if we knew how to do solar climate engineering, what's the preferred climate? We have said nothing—either Doug or I—about regional variability because we've talked about global changes. There is going to be a whole underlying signal of global variability that we simply at this point don't understand. Detection of early signal is problematic. It will take us at least a decade to know if we're actually cooling climate, and we're going to need 15-to-20 years of research to know if solar climate engineering is doable. I'm going to end here. I want to emphasize again that Doug and I and others think that it is the responsible thing for us to do this research to try to understand the issues surrounding solar climate engineering, but neither one of us wants to be seen as an advocate for solar climate engineering taking place at this point. Thank you. SIMON NICHOLSON: Thanks, Tom. We turn now to Pablo Suarez. Pablo? PABLO SUAREZ: Thank you very much, and hello, everyone, for being part of this conversation. [Slide 26] My name is Pablo. I used to be a researcher on climate and disasters. For the past decade or more, I've been working with a humanitarian team that specializes in climate. Some of you may know Maarten van Aalst, director of the Climate Centre, and also a member of the IPCC, a former lead author. These are exciting times for us scientists and terrifying times for us humanitarians. Things are changing rapidly, and there are many things we can do, but we don't know if we'll do them right. The world is literally in our hands. In the Anthropocene, we can, we are changing things. As it is in our hands, we can squeeze to create change, and maybe we can squeeze too hard. In terms of the decision-making processes, until now one of the largest driving forces and framings for how to do things has been markets. The invisible hand of markets is allocating resources—what happens; what doesn't—among other forces, of course, but what we know is that in the current context of decision-making, markets are not accounting for externalities. I do something; there are consequences to others, but I don't pay the price. When technology and markets lead to decisions that are unwanted and something goes wrong, there is another hand that has to show up. [Slide 27] It is the world of the humanitarian sector having to—by mandate, by Geneva Conventions, and so on—reach out and give a hand. What is happening now already is that because of a changing climate, among many other processes of change, the humanitarian sector is no longer able to keep up with the demand for our services of feeding the hungry, sheltering the homeless, healing the sick, and so on. The context of geoengineering, of solar radiation management, is one where we are confronted with risk; the risk of knowing that if we do nothing, the climate will continue to worsen to unmanageable levels, or the prospects of trying to manage this changing climate with solar radiation management, which opens a whole spectrum of other unknown things. [Slide 28] I use this photography to explain geoengineering to my colleagues in the Red Cross and Red Crescent and other sectors. I don't need to explain the science to you, but if we know that sunlight is coming and the glass is thickening and it is getting too hot inside, one of the options is to change the location of that rack on top of the roof and block some sunlight. We know with certainty that that would reduce global average temperatures. What we do not know is how does everything else change. What about the balance of the entire system? If there is any other load going in, whether it is geopolitics and conflict, or a regional distribution of precipitation, and other—vector-borne diseases and so on—could that small shift create tipping points? Could something go severely wrong if we do? What about things going severely wrong if we don't? In our opinion, both from science and from the humanitarian sector, solar radiation management and geoengineering has to be framed as a risk question. It is risk against risk, and it belongs as a decision-making issue that we confront, of course, addressing all the scientific questions that were highlighted by previous speakers. [Slide 29] We started engaging in the field of geoengineering in 2010 with two questions: The first one was: What about the most vulnerable people on this planet, the reason why the United Nations Framework Convention on Climate Change (UNFCCC) exists, avoiding dangerous change? How will those people help to make decisions? As of now, we know that they don't even know that SRM is an option, and there aren't mechanisms for engaging their concerns into the actual decision-making of whether or not to do research, whether or not to do deployment. The second question we posed had to do with who will pay for humanitarian work in a world where geoengineering has been deployed? What happens if there is the perception that a disaster happening over there is because of the deliberate action of someone over here? We posit that in addition to all the natural systems questions it is imperative that we look at the decision-making institutional, organizational, financial framings of how to manage climate risks with and without geoengineering.

[Slide 30] This is a paper that we published very recently, "Framing Geoengineering as a Humanitarian Concern." We know that things are inevitably going to change and there are inevitably going to be humanitarian consequences. What can science tell us in terms of atmospheric circulation, ocean acidification, and so on, but also how can we frame the choices that we confront as humanity, as a set of governments, as a set of institutions, as scientists, to understand the humanitarian consequences of risk decisions that we confront?

[Slide 31] In this paper there are five key points that we wanted to share with you: One is that the possibility of geoengineering has major implications in terms of what may happen to the most vulnerable; whether we do it or we don't, how we frame it, what parameters are we looking at. As mentioned earlier, especially by Tom, the global averages are very easy to predict—temperature will go down if we deploy—but in terms of what happens to one location versus one in the next province, there are many, many unknowns, and we need to understand better what would happen and what would we do in that case.

A second point raised by this paper is that nobody likes to be in the hands of someone else. No one likes to be a rat in somebody else's laboratory, and that is what we have been doing inadvertently with CO2 and so on, but now we're talking about a very different scale. Just like in normal scientific processes where we ask a subject if he is willing to be injected to test a drug before we inject him with the drug, how can we envision the processes of engaging especially the most vulnerable in decision-making?

A third point we raised is that a lot of the conversations that have been happening in the field of solar radiation management and geoengineering have been dominated by extremely rational people; people who work with atmospheric science, people who work with global governance. Unfortunately we know, if you look around the world today, that the most serious threats are related to decision-making processes and incentive structures and forces that do not respond to our typical assumptions of rationality. We need to recognize—and we offered to IPCC—the need to consider that decision-making in the context of geoengineering may be influenced not only by rational choice and optimal allocation of temperature and precipitation over time, but also to everything else that matters to people who today are making decisions on this planet.

The last point to highlight: In this paper we coin the term "predatory geoengineering." Once we know that the planet can be tweaked, that we can send the Intertropical Convergence Zone (ITCZ) a little further north or to bring temperature a little further down in one place, there will be the inevitable temptation by some geopolitical actors to create ideal conditions for them while creating consequences elsewhere, capturing the benefits of geoengineering for themselves. There could also be the possibility of geoengineering as a weapon. We do not know how things will play out, but it is not only about atmospheric science and optimization of a global outcome. There are going to be all sorts of other considerations to bear in mind, and this potentially predatory behavior is particularly risky to us.

Slide 32

As an illustration, on the left you see for the year 2003 that the Senegal River, when it reaches the Atlantic Ocean, goes along the coast separated from the Atlantic Ocean by just this thin sandbar, the Langue de Barbarie, and there was a big risk of flooding in the capital city of that area called Saint-Louis—about 100,000 people. In 2004 you see an opening in that sandbar which was created to reduce the flood risk further north so that the water could evacuate through that last section of the river, evacuate faster, with less problem in the capital city.

Well, guess what? By 2009, a breach that had started as four meters and then became wider and wider was already more than a kilometer wide, and the freshwater was becoming seawater, and the entire ecosystem of that place changed. You see in 2009 near the center bottom of that area there is a white rectangle highlighting the village of Doune Baba Dièye, about 800 people, having a sufficiently prosperous life in that part of the world. Once they were no longer separated from the ocean, of course things started changing for them.

Slide 33

This shows the behavior of the river over time. There was a peak river level, seasonal, and the moment the breach was made to avoid excessive growth, the intended consequence was accomplished. The river levels did not go up as high as was feared; there was reduction of flood risk in the city of Saint-Louis, where 100,000 or so people live. But guess what? Other things changed.

Slide 34

You can see satellite images of the village of Doune Baba Dièye across from the opening. In 2003, nice easy village, mangrove on the river; 2009, there are already no mangroves. I was there, and you will see a photo. The water is already on the edge of homes. In 2013, most homes gone; in 2016, there is nothing left. And of course, those people were not compensated, some people died, and this is trouble for them.

One hundred thousand people versus 800 people, I can understand the value of such decisions, but we cannot make choices that create very, very catastrophic outcomes for some to make someone else better. It is like if you in the audience have a problem with health, and you decide to kill me and take my organs, that would not be morally acceptable; that cannot be humanitarianly acceptable.

[Slide 35] This is a photo of that village in 2009. We know with certainty that whether we do geoengineering or not there will be catastrophic changes happening around the world. If we make decisions, we need to understand a scientific governance decision-making process that thinks of how are we going to deal with unintended consequences.

[Slide 36 (skipped), Slide 37] We have been proposing conversations with others, and we have a lot more to learn and a lot more to share. We wish all the best to IPCC as you make decisions on how to manage risks with or without geoengineering. Thank you.

[Slides 38 & 39 skipped]

SIMON NICHOLSON: Thank you, Pablo. Let me invite Tom and Doug back onto the screen if I may, and we'll turn to some questions from the audience. The first question, Pablo, builds off your desire to look at this as a risk-risk conversation, so I wonder if we can start to flesh out some of the risks of solar geoengineering that haven't yet been mentioned that go beyond surface temperature levels and precipitation and compare those to what you imagine in a world of climate risk absent solar geoengineering. How do we start to understand this risk-risk comparison that Pablo is inviting us to think about? THOMAS ACKERMAN: If I might take a little bit of exception to the way Pablo framed the problem because I felt like his conversation was pointed very heavily at the possible consequences of climate engineering—which I fully understand and fully concur with—but did not emphasize that we face exactly those same issues. We are already rats in somebody's laboratory, and so the question is not whether we're going to be rats or not going to be rats; it is "what does the laboratory look like?" And until we figure out how to get CO2 emissions under control, we may very well say the risks associated with climate engineering and keeping the temperature down to some level may be much less risky than allowing CO2 to go on unchecked. I think we need to be careful about how we phrase this and not imply that not doing geoengineering doesn't have a risk associated with it. PABLO SUAREZ: Yes, Tom. I hope I conveyed this as a risk-risk; I'm sure I mentioned it several times. The reason why I want to emphasize the potential negative consequences of our choices is that there is a tendency to think of the global averages. You and Doug have spoken very clearly about the things that we do not know and how we need much more research if we are to make decisions responsibly, and we celebrate that. Without a doubt there will be problems if we do; there will be problems if we don't. We are rats in this laboratory. The main difference is that without geoengineering, the laboratory is shaped by many, many different small decisions that are not intending to make it into a laboratory. As we frame decision-making and as we frame the choices about risk, we need to think about the most vulnerable: What will happen to them if we don't stop the warming, and what will happen to them if we try to stop the warming with technology? I think we are in agreement, and it is a matter of emphasis. SIMON NICHOLSON: Doug or Tom, in terms of the published literature, where do folks go to understand the risk profile of different climate engineering response options? DOUGLAS MacMARTIN: I think my reaction would be that I would be very cautious about interpreting the risk profile of any model simulations to date on solar geoengineering. I think the research to date has been wonderful. We are learning an awful lot about how the climate models respond to different forcings, but there is a long way to go before I would say I believe what's going to happen. I think the one robust conclusion is the one that both Tom and I mentioned, which is that overall, say, a 1.5 °C world with solar geoengineering will be a bit drier than a 1.5 °C world without solar geoengineering, but you also have to keep in mind it will still be wetter than a pre-industrial world. What exactly the regional consequences are, those will depend exactly on how you do it. For example, with stratospheric aerosols you have a choice of what latitude you are going to inject aerosols at, and those choices will influence the resulting climate. So saying somebody injected aerosols at the equator in a model and this is what happened, first of all, that might be one model; and second, who said you had to inject the aerosols at the equator? Until some of that research has gone forward, it is a bit hard to say that we know what the impacts of doing solar geoengineering would be on a regional level. SIMON NICHOLSON: We have a question actually about regional applicability of these sorts of technological response options: Is it possible to solar geoengineer in a regional fashion, and might that be a pathway to better understand these technologies? THOMAS ACKERMAN: Perhaps I should try to answer that. If you think about the stratospheric aerosol injection, it's difficult to think about doing stratospheric aerosol injection in a truly regional fashion, and the reason is that as soon as you put material into the stratosphere the winds in the stratosphere will distribute it around the planet. We know that the time for removal of aerosol that has been injected into the stratosphere by volcanic eruptions is somewhere on the order of four years, so it is hard to imagine that as being regional. One of the reasons why we're looking at the marine cloud brightening aspect is that, in fact, it is possible to think about doing it regionally. You could think about modifying clouds in a particular area that would cool the particular area. The difficulty with that, as I'm sure all of my climate friends would say, is that we know that the atmosphere has teleconnections; we know that changes in particular places change the climate elsewhere. The grand example of that that occurs every two years is the El Niño southern oscillation in the tropical Pacific. We see the big change in the tropical Pacific, but it changes rainfall patterns all around the Pacific. So we need to be very careful of saying, "Yes, we can do regional change without impacting anywhere else." We also have to think about the magnitude of that particular regional change. The bigger the regional change that you force, the more likely you are to force teleconnection somewhere else. SIMON NICHOLSON: Doug, anything else to say on that question? DOUGLAS MacMARTIN: I'll just add one other thing in context. If you think about, oh, maybe we could do marine cloud brightening here, and it will help the rainfall in California, that might be steering a storm somewhere that would have gone somewhere else. The other thing that has been suggested on a regional level is that the reason we would want to do geoengineering with aerosols in the stratosphere is because of the lifetime. So if you put the aerosols in the troposphere, then in principle they dissipate more quickly and you could have a regional effect, but the flip side of that is that now you need an awful lot more aerosols because they rain out very quickly, and you now have issues with acid rain and health, pollution, and so forth. Even with putting aerosols in the stratosphere, they do eventually come down, but because the lifetime is so long in the stratosphere the amount that you need to put up is relatively small compared to what we currently dump in the form of pollution. PABLO SUAREZ: One additional way to respond to that question is that if a decision-maker cares for a region and wants to accomplish a certain constellation of parameters for that region, it is doable to try to accomplish that regional outcome by changing the climate of the planet where you leave those magic powders; is it in the equator or further north or further south, how much of it, etc. Whether you trust the models or not, you can attempt that, and that is one of the reasons why we are engaging in this field, that there is such a possibility for geopolitical tensions that will reallocate attention, harmony, distress, funding, and many other things. THOMAS ACKERMAN: If I could quickly correct or amplify a little bit what Doug said, when we talk about the marine cloud brightening, we're talking about injecting salt particles at low levels that would change clouds. We are not talking about putting sulfur into the troposphere, which is sort of what Doug was talking about, about putting aerosol in the upper part of the atmosphere. There is a lot of complication here, and I don't mean to overemphasize the complication of the science, but simply to state the same thing that Doug said, we have a lot to learn yet about how this is going to work. I think one of the issues that the science community needs to confront is: Is this kind of research going to be funded? Are we going to say, "Yes, we want to do this"? Because right now there is not a whole lot of support for this kind of research. SIMON NICHOLSON: In addition to the complications on the physical science side, we're having some questions that start to set up the complications on the governance side. So, a question for you, Pablo, building on Tom's notion that we are already rats in somebody's lab, the question is: Most jurisdictions would strongly distinguish between inadvertent consequences of greenhouse gas emissions and deliberate climate engineering as regards responsibility, liability, and loss and damage. Is that conversation happening anywhere in the policy space? PABLO SUAREZ: I think that not enough conversations are happening in the decision-influencing space. There needs to be more of that. Almost everyone I have met in the conversations about geoengineering, whether from science, from governance, or from policy, have been very eager to raise exactly that question: How are we going to deal with that fundamental distinction between unwilling or not core intention versus deliberate manipulation? What we know is that even though we understand exactly what happens with externalities of carbon emissions and the like, there are no consequences to doing it now, and without a global framework for geoengineering, the default is that the only way to stop someone from deciding that it is time to deploy geoengineering may be with the threat of geopolitical forces, whether it is economic sanctions or something more forceful. So we need to recognize that the dialogue which has begun to expand from the scientific arena and the governance scholarship arena to the IPCC and, by extension, to the UNFCCC, we need more of that, and we need to be realistic about the incentive structures that create embracing change, embracing regulation, embracing governance, or rejection of the encroachment on sovereignty and the like. Another thing to bear in mind is that the costs we're talking about are rather steep, but they are not outside the scope of a few very wealthy individuals or companies who may feel tempted to be heroic and save the planet by cooling down the planet. My concern is that very likely there will be a mismatch between "how much does it take to know so that we can make responsible decisions" versus "what does it take to stop an irresponsible decision-maker who thinks he or she or they are being responsible by just going ahead when no one can formally stop them"? SIMON NICHOLSON: Let's talk about costs. We have a question from the audience about costs. THOMAS ACKERMAN: Very quickly, this whole issue of intent is something the ethicists are quite interested in, and some of it is being addressed in the ethics literature. SIMON NICHOLSON: In the next segment we'll hear from an ethicist who will address some of those sorts of concerns. Thanks for raising them, Pablo. A question from the online audience is about costs. DOUGLAS MacMARTIN: I guess my reaction broadly speaking would be that the direct costs of these ideas are likely to be very small. In some sense, whether they are $10 billion or $20 billion a year is almost irrelevant. The actual costs of doing this are much more the climate impacts of it. So the direct costs are negligible compared to the costs of altering the energy system, for example. But if you were to put up a reasonable process for loss and damage or climate insurance or something like that, that is probably a far, far larger dollar amount. In terms of stratospheric aerosols, basically people have done the analysis and said, "We could probably design aircraft that could get high enough up into the stratosphere to put material up there." Those aircraft don't exist today, so don't worry. Nobody is physically capable of doing this within the next number of years, but I don't think it is fundamentally difficult to do either that or the marine cloud brightening. SIMON NICHOLSON: Anything else on costs? PABLO SUAREZ: It is important to reemphasize the distinction that Doug made. A responsible decision-maker will look at the full spectrum of consequences and call them cost or benefit, right? It is entirely possible that a perfectly knowledgeable entity could say that "We know that the benefits are bigger than the costs, and we should go ahead and do it," but what we know is that in terms of deployment, the costs of deployment are to load some magic powders, send them up there and disperse, and that cost is—I've been accused of using a questionable analogy, and I accept that questionability, but—order of magnitude, a nuclear weapon. A nuclear weapon is intended to kill people; solar radiation management is intended to save people. But if you think of who is technologically capable of creating these technologies, order of magnitude? My goodness. It can be done, and there are lots of irresponsible forces out there. I prefer the analogy of responsible choices, all the things that we are doing to improve this planet through knowledge, through technology, through science. Let's hope that we can aspire to the more comprehensive picture that Doug has been portraying. DOUGLAS MacMARTIN: Thank you for clarifying that for me. PABLO SUAREZ: And just to be very clear, as far as I know there has been a lot of portrayal from the outside world about the geoengineering actors as being "forces of evil" and attempt to control my experiences; that my fellow panelists, and pretty much everyone else, is decidedly motivated by good intentions, of making good in the planet, and we celebrate that goodness. Thank you. THOMAS ACKERMAN: I'm glad you said that, Pablo. I was getting worried about the "magic powder" stuff. Most scientists don't believe in magic powder, but I can't speak for all of us. SIMON NICHOLSON: We have a couple of related questions on research timelines and about the timeframe to deployment. Tom, one of these questions is directed at you: Has that 20 years to responsible deployment notion been published anywhere? And could you say something about timelines for "irresponsible" deployment? THOMAS ACKERMAN: The actual 20-year kind of timeline, as far as I know, has not been published anywhere because it's difficult to say exactly where we would stand. That diagram that I showed you addresses that subject somewhat and is being published in an article in Earth's Future, and the leading author on that is Alex Lenferna, who is a graduate student at the University of Washington. It's co-authored by my group of atmospheric scientists and a group of philosophers working with Steve Gardiner. You can find some additional information there. The caption on the bottom of the slide gives the title of the paper. The second question was about irresponsible deployment. Doug just made the point, and I would concur, while we think this is doable in some sense, the technology that we need to make it doable—high-flying aircraft, sprayers for marine cloud brightening that could generate lots and lots of aerosols on lots and lots of ships—currently doesn't exist. I think it's unrealistic to think that even an unreasonable timeline that says a couple of years is simply not possible, because while we might have the technology in a year or two if we went on a crash course to do sort of small-level experiments, actually producing the amount of material we need for global delivery is probably not within our reach in a couple of years. I don't think it is unreasonable to think if you went on a crash course with the technology for dispersing stratospheric aerosol that you could do that in something like five-to-ten years. I think that is a reasonable guess. DOUGLAS MacMARTIN: I would concur with that. SIMON NICHOLSON: Another question on timeline. There was a question, Doug, directed at something that you said: Many questions you're asking about SRM or solar geoengineering and its forcing impacts seem to the author of this question analogous to questions that have been asked about CO2 since the 1980s. The suggestion is we don't yet have good answers to some basic questions about CO2 in the atmosphere. What makes you think we can resolve questions about solar geoengineering within the decade or so? DOUGLAS MacMARTIN: I think that's an excellent question. I'll try to think of what the best way to answer that is. I think there are an awful lot of things that we have not done at all on the solar geoengineering side, that we have already got more knowledge of on the CO2 side. I would say that if we had a major research program with 20 years or so, we would know an awful lot more than we currently do about solar geoengineering, but that there will always be big uncertainties. In particular, I think one could probably resolve some questions—I'll always pick stratospheric aerosols as my analogy to go to, but there are comparable issues in marine cloud brightening. For example, I think you could launch balloons up into the stratosphere and measure chemical reaction rates and understand aerosol and microphysics better than we currently do, but you're never going to do a good job of evaluating exactly what the climate impacts are on a regional basis from doing geoengineering. I would also say we don't know exactly what the regional climate impacts of increased CO2 are. The reasons for uncertainty on those two things are actually very similar. The reasons we don't understand a lot of the responses to the CO2 are because of uncertainty in regional feedbacks, and they are exactly the same climate feedbacks that respond to solar geoengineering. So I think it is potentially a little bit misleading to think, Oh, there's all this climate uncertainty from CO2 and then you're going to add more uncertainty from solar geoengineering. In actual fact, the overall climate response may be less uncertain with solar geoengineering than it would be if you simply allowed the climate to keep warming into a realm which we have no experience with. PABLO SUAREZ: Resonating with that, there is ignorance, and there is always going to be some ignorance. The question is: How much reduction of ignorance is enough to justify the decision to act or not to act? If I may complement the earlier analogy, I think for now my favorite analogy for geoengineering is chemotherapy. We have one organism, planet Earth, it is undergoing too much growth of one thing that we don't like—global temperature and many other things—and we know that if we inject something into the system, the chemotherapy agent, then something will be accomplished. We will bring down this threat. But other things may change in the organism. We don't have multiple bodies. We don't have rats to test. It is one planet. How much do we need to know before we make the decision to deploy chemotherapy, the geoengineering therapy? That is the fundamental question that IPCC can help to frame; the risk versus risk, how much knowledge is enough knowledge, what framings for risk analysis, for infusing risk into decision making, how to shape science. It's tough, and we are in trouble whether we do or we don't. [Simultaneous discussion] DOUGLAS MacMARTIN: —today but defining at what point we do know enough is not easy. SIMON NICHOLSON: We have about 10 minutes left in the segment before we turn back to Janos and the conversation about governance. Just to sharpen the conversation that is taking place at the moment, there is another question here: With limited resources for funding academic research, make the case for SRM research at this stage. THOMAS ACKERMAN: I'll make that argument. First of all, I will state flat-out that that's a red herring. The argument is not whether or not we have to steal from this pot to put it in that pot. The point is that we are underfunding climate research everywhere. We are not recognizing the severity of the problem and not investing in the research, and by that I don't just mean physical research; I also mean the kinds of things that Pablo is talking about, about how do we understand the consequences of actions and inaction. I think that's a red herring. I know it's a popular ethical argument, and I think it's the wrong one to have. The question is: Do we need to do this? If we need to do this, then let's talk about how to find the money, how to find the support for it, and not get ourselves wrapped up in the idea that I'm taking money from somewhere else that needs that money. What we need to do is decide what the priorities are, and if this is a priority, then let's go out and fund it and not say, "Well, we're stealing it from somewhere else." DOUGLAS MacMARTIN: I just want to add one thing there. I think the worst scenario would be we don't do the research and 20 years from now, whatever it is, massive heat wave in India and crop failure, and they go, "We have to do this geoengineering thing to solve things," and go ahead and try to do something without having done the research. I would far rather be in a position 20 years from now when somebody goes ahead and says that to be able to say either "No; here's why not" or "If you are to do it, here is our best guess of the best way to do that and what we think the impacts are and what our confidence in those impact assessments are." I would also point out that within a rounding error the current funding is zero. SIMON NICHOLSON: One of the big complications, Pablo, as you well know, in this space is that anybody who talks about climate engineering gets accused of bringing legitimacy to an area that should in fact not be investigated, because it's a distraction from the rest of the climate change response agenda. Can you offer support for the sorts of research that Tom and Doug are talking about? PABLO SUAREZ: It is not my job as Red Cross to offer support. What I can say is that they are difficult decisions we confront. Everyone, and the humanitarian sector in particular, cares for reducing suffering, regardless of what causes the suffering. It can be a bullet that someone shot; it can be a natural phenomenon, an asteroid falling from outer space and causing trouble. We need to take care of people. In the context of solar radiation management, we have dealt within the past few years with something very similar to when we started exploring adaptation to climate change, when mitigation was portrayed as the only thing we have to talk about, and the mere conversation about adaptation to climate change, dealing with consequences, being a derailment from addressing the causes. What we see is that the train has left the station. The media, the researchers, the Nobel Prize winners are talking of geoengineering, and so it is no longer plausible to assume that if we just don't talk about it then nothing will happen. Whether or not we want to lend legitimacy or not, it is a subjective choice based on a million things. What I understand is that we have to be very careful about estimating the consequences of our showing up. I fully accept that I am losing some friends, to be frank, because of the perception that I am lending too much status and credibility, which is an overestimation of what we as Red Cross can do, I think. But in any case, it is true that just by showing up there are consequences; not showing up has consequences, and each entity will have to confront those decisions. I really think this is a researchable question: How can we use the conversation about geoengineering to point in the direction for the need to really accelerate our need to mitigate strongly, our need to address the root causes of everything? If we portray this frankly mad idea of manipulating the global climate by blocking sunlight, if that is what we need to be thinking about now to address consequences, why don't we do the, I hope, easier thing of addressing the original consequences of messing with the atmosphere? I hope we can investigate that and get it done. SIMON NICHOLSON: We've got about five minutes left. There are a couple of loosely related scientific questions that I'll kick back to Doug and to Tom. One question here: Is there anything that can be done on the research side to cut down on the 10-year time lag between actually doing something and reading the signal out of the atmosphere? Then there is a question about what can be learned from natural analogues in this space. THOMAS ACKERMAN: So let me try and answer the first one, and maybe Doug wants to tackle the natural analogues. There is very little that can be done, I think, to shorten that 10-to-15 year time scale. That really involves the natural variability of the system. The only way I can see to shorten that time period is something you probably you don't want to do—and Pablo will get really upset—because the way is to generate a much bigger signal. What you would do is go out and do a massive experiment and say, "Okay, I'll see the effects of that massive experiment in a much faster time." On the other hand, if something goes wrong, you've just bought into a massive experiment and a massively bad outcome. So I don't think you want to run the project that way. That's the only thing I can tell you, is given the natural variability in the system and the fact that we're very likely not to be able to do a massive experiment, I don't see any way to shorten that. DOUGLAS MacMARTIN: I would agree. On the analogues, there is certainly an awful lot we could learn if another large volcanic eruption went off. An awful lot that we've learned about stratospheric aerosol geoengineering we learned from the Pinatubo eruption, for example, although we actually don't have all the monitoring capability in place that we would like to have. So if a large eruption went off tomorrow, we would not learn all of the things that we'd like to learn just because we won't have the data collection that we would like to have. That said, there are definitely differences to volcanic eruption versus continuous injection of aerosols into the stratosphere, and so while we would learn a lot and that would help validate models, it's not the same thing, both in terms of the climate response—the climate responds differently to a pulse of forcing than to continuous—and the microphysics of the aerosols is different. On the marine cloud brightening, Tom in particular has proposed some relatively straightforward experiments to understand the cloud-aerosol interactions. I think I've sort of said before that is one of the biggest uncertainties there is in climate science, and if we had never heard of geoengineering at all, those experiments would almost be more likely to go forward than less likely. We can learn things on the marine cloud brightening from observing ship tracks. People have actually looked at the low volcanic eruptions that put aerosols into the marine boundary layer. Tom, you wanted to say more about the experiment. THOMAS ACKERMAN: I simply wanted to say that if people want to follow up that question, there is an article in Climatic Change, I think 2011, by Rob Wood and myself, Wood and Ackerman, that describes the sort of scenario of how you would go about doing an experiment and what some of the questions would be on this very important aerosol-cloud problem and how we could address that. SIMON NICHOLSON: We have just about two minutes to go. There is a comment from somebody just talking about the role of the IPCC on the science side of this process, making the point that the IPCC does not perform new scientific investigation. What we have asked each of the presenters to do is assemble a group of published articles that we will then post which point to some of the main points that come out of the presentations today. In the wake of this webcast, we will point to the scientific literature in a more coherent fashion. A final question here as we wrap this segment: Where is the dividing line between a solar radiation management test and an actual intervention? THOMAS ACKERMAN: I would refer you to that article I mentioned before by Lenferna because that's exactly what we're trying to discuss: What is the difference between a large-scale test and deployment and what are the ethical questions involved? That is really a question of time and forcing, and it is a little hard for me to explain it all right now. We tried in that paper to differentiate those two. DOUGLAS MacMARTIN: I would just say I don't think you can actually measure the climate response without a forcing that is large enough to make it practically equivalent to deployment. I think you can learn process stuff with tests—that is a very different scale—but I think there is a sort of natural scale separation between trying to understand processes and trying to actually understand the climate response. PABLO SUAREZ: In addition to the atmospheric science side of things of test and intervention, we need to acknowledge that merely this conversation constitutes an intervention. The climate system is dependent not only on atmospheric molecules and chemistry; it is also about organizations having conversations and creating expectation. My hope is that the IPCC will not only consolidate what exists, but also shed light on what doesn't exist yet and is needed for more informed, more responsible decision-making. SIMON NICHOLSON: Thanks to Doug MacMartin, Tom Ackerman, and Pablo Suarez. We'll turn back now to Janos Pasztor to introduce the next segment. JANOS PASZTOR: Thank you very much, Simon, for leading a very excellent discussion, and thank you to the various panelists who provided some really interesting insights. Now we come to the second part of the webinar to talk about the ethical issues, social acceptability, public perception and, of course, the governance of these issues. Already in the discussion we had quite a few issues that came up in terms of the ethical issues that arise from these technologies—intergenerational justice and, of course, social acceptability. These have all come up in different parts of the discussion so far. There is also the question of perception. One of the questions that was posed by one of the participants to this seminar was, "Wait a minute. Isn't that already happening?" There is a perception that some are already engaged in massive solar engineering. While there may not be any facts behind that, there is a perception, and we have to deal with issues of perception as well as the acceptability of formal research and other activities. Of course, all of this will have to be governed somehow. There are institutions, there are governance mechanisms that can address some of these issues, but certainly there is no comprehensive set of frameworks that would be able to govern the totality of solar engineering as we know it. These are some of the issues that we will explore in the next session. We have a number of speakers. First of all, we will have Holly Jean Buck from Cornell University College of Agriculture and Life Sciences, who will address issues of social acceptability. Then we will have David Morrow, who is faculty fellow at the Forum for Climate Engineering Assessment at American University. He will talk about the ethical issues. Then we will look at governance issues, first with Arunabha Ghosh, who is chief executive officer of the Council on Energy, Environment, and Water in New Delhi. Finally, Ted Parson, professor at the University of California, will also address some governance issues. During the question-and-answer session, I will call on three short discussions. One of them will be Will Burns, who is co-director of the Forum on Climate Engineering Assessment (FCEA), which is, of course, co-hosting this event; Cynthia Scharf, who is senior strategy director at the Carnegie Initiative; and Simon, who you've already seen operating as facilitator of the first part. With that, I'd like to call on Holly to give your presentation, please. Thank you. HOLLY JEAN BUCK: Hi. Thanks so much. It's great to be able to engage on this topic without having to take a flight anywhere. [Slide 40] So what I'm going to do today is briefly review the existing empirical social science on geoengineering. When it comes to empirical work with human respondents, there have been about 30 studies since 2009. About half were large-end surveys and half were deliberative workshops and focus groups.

[Slide 41] I'll mainly speak about peer-reviewed literature that focuses on the general public. I should mention that there have been regionally-focused workshops for experts and professionals, and also work done by the Solar Radiation Management Governance Initiative (SRMGI) around the world. The earliest efforts happened in 2009 or 2010 and were part of large reports by the UK's Royal Society and the U.S. Government Accountability Office. Much of the work in the first few years arose from interdisciplinary national funding programs in the United Kingdom and also in Germany. Subsequent deliberative work drew upon the lessons from these earlier studies, for example, by exploring participant reactions to particular framings, such as the climate emergency or ideas about what is natural.

Slide 42

As part of the background for this talk, I wanted to mention the taxonomy of climate options set out by the 2009 Royal Society report, because this framing was very influential in the social science that has been done. Many studies, even recently published ones, set up the research as comparing or choosing between different various SRM and carbon dioxide removal (CDR) technologies. This taxonomy was a bit misleading in that it depicted somebody who is choosing between discrete options. From a policy standpoint, these need to be looked at as a package deal. We would likely want an SRM/CDR system so that we could remove enough carbon from the atmosphere to ramp down the solar radiation geoengineering as discussed earlier in this webinar. There aren't really any social science studies yet that address a temporary geoengineering or peak-shaving scenario like Doug described earlier.

[Slide 43] What does this existing research look at? Here are some of the questions addressed through surveys and experimental methods. They investigate how widespread public knowledge is and what factors drive public perceptions of solar geoengineering. There is also a body of research on the moral hazard argument: Does solar geoengineering interfere with willingness to mitigate, and so forth.

Slide 44

I'd like to back up and address the question of why we need social science input on geoengineering research in these very early stages. There are varying rationales for doing social science research on climate engineering. The research at this point can be seen on a spectrum. On one end of the spectrum are studies measuring public opinion in order to make sense of what risks are socially acceptable. In the middle you might find studies communicating to publics about research for science education or transparency or consultation processes for governance or public oversight of research. On the far end of the spectrum, you might find upstream or public engagement with deliberative activities intended to incorporate publics into the research process, which would hopefully produce better science on questions of public interest and allow publics to shape the research agenda. So in general, social scientists pick the method that suits their rationale. [Slide 45] There are a number of challenges embedded in doing this type of work. Social science methods generally lend themselves to investigating things which already exist, and because solar geoengineering is a speculative future activity and one which people don't know much about, there are two major methodological limitations: (1) people's perspectives may shift over time as they learn more; and (2) when the researcher is the one informing participants about the subject, their framing can bias the results. So respondents may be becoming more familiar with this topic through the concept of chemtrails, which is an idea that has been increasingly intermingled with climate engineering over the past two years or so. In short, many people believe climate engineering is currently going on for climate modification or other reasons. I put on this slide a Tweet from Kylie Jenner, which was then re-Tweeted by Kim Kardashian. To be honest, I don't know too much about these people, but I've observed that they have 20 million and 51 million followers on Twitter, respectively. So it is entirely possible that people are, or will be, getting information about climate engineering for the first time through means and messages such as this. While surveys tend to give either a brief description of climate engineering or show respondents a video that describes what it is, people are coming to the topic with background knowledge from sources that mix up geoengineering with chemtrails. We're not sure how that will shape the survey responses. A third issue is that public engagements are constructed engagements, and hence their publics are constructed publics. Deliberative engagements of the types that have been done in the United Kingdom and other countries might be a method that wouldn't transfer that well to places with different cultures of citizen participation. [Slide 46] Across the countries looked at there have been remarkably similar concerns, especially about controllability, which extends to how well you can control both the ecological and social implications of this. Some of the findings included that the framings around naturalness or climate emergencies matter; that publics are concerned with unexpected side effects as well as governance challenges; that discussing solar geoengineering may improve the will to mitigate as well as decrease it in different contexts; and fourth, that there is conditional or ambivalent support for research. The study that just came out by Visschers et. al. indicated that people from countries that are less prepared to mitigate and adapt to climate change seem to be more supportive of SRM. That was from a six-country comparison, including looking at China; it is the first study to do that. It is a pretty broad statement, but it points to an important line of further research. [Slide 47] I would evaluate this modest body of literature as a good start in that it points to what needs to be done, but I'd be wary of concluding too much from it. For me, some of the main takeaways are that publics are able to deliberate and catch some of the nuances and key dilemmas of this concept within an hour or two. The main issue is that the work is too confined to cultural contexts in a few countries. There are some other key gaps: There aren't any studies yet that measure how attitudes change over time. I am actually involved in a project in Finnish Lapland where we conducted focus groups and are planning to return a year later, and as part of that to look at how people's feelings and concerns have changed, but there is not really any longitudinal data. Another gap is that there has been virtually no engagement with U.S. publics. My initial qualitative fieldwork on perceptions of solar geoengineering in the United States has suggested significant differences between the United States and European countries due to things like climate skepticism, political polarization, loss of trust in institutions and the government, and the politicization of climate science. [Slide 48] This brings me to another point, which is that we need to learn not just about some general public—if that can even exist—but about how specific publics think about this technology. I've used this cartoon here to point out why people concerned with chemtrails have vocal and enduring concerns. They have confirmation about this idea when they look up. But they are not the only mini-public that matters when it comes to decision making, and it would really be worthwhile to look at several mini-publics or cultures. There is a huge role for NGOs in this work. The research that has been done indicates that publics want to discuss geoengineering not as a yes-no verdict on a particular technology or approach, but in the context of a broad array of climate futures. NGOs and community organizations are already facilitating some of those conversations. [Slide 49] Why don't we know more after about a decade of looking into this? Some of the further limitations are the cost of it. It is challenging to build international collaborations on social science on geoengineering because people in other countries are focusing limited resources on present pressing challenges. A lot of my colleagues would rather focus their attention on mitigation or adaptation rather than this more speculative phenomenon. [Slide 50] There are all kinds of future research that could or should be done, but in brief I'll just close with these two: More research about how citizens seek, find, and interpret information about climate engineering; second, world-wide understandings, particularly in order to incorporate people's visions, preferences, concerns, or goals into the research process itself. I'll wrap up there. Thanks very much. JANOS PASZTOR: Now we would like to go on to the next speaker. That will be David Morrow talking about the ethics. David, you have the floor. DAVID MORROW: Thanks, Janos. [Slide 51] One of the striking things about the geoengineering conversation is that it has incorporated ethical concerns more or less from the beginning. So there is already a decent body of scholarship about the ethics of solar geoengineering. That is what I'm going to discuss today. As you might imagine, this scholarship includes a lot of disagreement, but I want to start by emphasizing a key point of consensus that echoes some things we've already heard today, and that is that using solar geoengineering as a replacement for emissions reductions would not only be a terrible idea, it would be terribly unjust. So the context for this discussion is that we are trying to figure out whether, or how, we might use solar geoengineering as a supplement for mitigation, not a replacement. [Slide 52] Another crucial piece of context here is that a lot of the ethical concerns surrounding solar geoengineering have to do with the climatic effects. It is important when we're thinking about those to remember that the context for that is comparing the effects of solar geoengineering to the climate risks facing a world with significant climate change. We're not comparing these to the present climate; we're not comparing them to some ideal situation in which rapid mitigation has prevented significant climate change. And it is not to assume that such rapid mitigation is impossible; it is to assume that if we manage such rapid mitigation—which I hope we do—we won't need to be thinking about solar geoengineering anyway. So the even broader context is we're thinking about whether, or how, we might use solar geoengineering as a supplement to mitigation in the context of significant climate change. [Slide 53] I want to start by talking about some debates in the ethics of deployment, and I'm going to survey those debates under three headings: justice; the precautionary principle; and humanity's relationship to nature. [Slide 54] On the topic of justice, there are three major kinds of justice that people discuss when they're thinking about geoengineering. The first is the matter of distributive justice. As we've heard, solar geoengineering has the potential—we think—to significantly reduce global climate risk. That means that it might reduce suffering for a lot of people, and it might reduce damage and risks to various natural systems. That is the reason we're talking about it in the first place. That is the core of the ethical argument for solar geoengineering. But as Pablo emphasized earlier, there are going to be some people who are made worse off by any deployment of solar geoengineering. So the question of distributive justice is whether the risks and potential benefits of solar geoengineering could or would be distributed fairly. I would emphasize, as other people have done, that that is not just a matter of physical science or engineering; it's a matter of politics, because how those risks and benefits are distributed depend on exactly how it is deployed, depend on how humanitarian work is financed, and so on. It is also ethically significant here that geoengineering would be the deliberate manipulation of the environment for the purpose of changing the risks facing people and natural systems. Intentions matter in ethics. As a participant pointed out earlier, they matter in law, too. So we need to think about the nature of geoengineering as a deliberate act when we are thinking about the climatic consequences. The next kind of justice that people discuss is procedural justice. This is a question about whether the processes by which decisions get made for deployment of solar geoengineering are fair decision-making processes. Pablo mentioned this question, too: Are the most vulnerable people able to have a voice in these decisions that will affect them so profoundly? Arguably a decision to deploy solar geoengineering would be an unprecedented global social choice, and so it is unclear whether our existing global governance institutions are morally adequate to the task. Indeed, it's unclear what it would take for them to be morally adequate to the task. The next kind of justice that people discuss in this conversation is intergenerational justice. The question here is whether solar geoengineering could help us or hinder us in fulfilling our responsibilities to future generations. On the one hand, solar geoengineering might significantly reduce the harms and risks that our emissions impose on future generations, and so it might help us fulfill our responsibilities, but on the other hand it would create new risks. Doug alluded to this earlier. Under certain circumstances, solar geoengineering would create the risk of a so-called "termination shock," this spike in global temperatures following the interruption in solar geoengineering, which would be imposing a new risk on future generations. Another major question of intergenerational justice is something Holly referred to, the so-called "moral hazard" problem. The worry here is if solar geoengineering, or even the prospect of solar geoengineering, were to undermine some country's commitment to mitigation, it might in fact make the world worse off on balance. [Slide 55] Let's turn now to precaution. Precaution is a much-cherished value in environmental circles. With respect to solar geoengineering, it cuts both ways, depending on your interpretation of the precautionary principle. In all its many forms, the precautionary principle counsels us to avoid excessive risk. But the problem is that what counts as an "excessive" risk depends on, among other things, value judgments. If you see the excessive risks coming from the deployment of solar geoengineering itself, you will argue that precaution forbids us from deploying solar geoengineering, whereas if you see the more excessive risks coming from allowing global temperatures to rise faster or higher than strictly necessary, then you might argue that precaution requires us to deploy solar geoengineering. I can't resolve that dilemma for us—more research might help—but I bring it up to emphasize that if you find yourself on one side of the debate or the other and you think that precaution supports your position, you are right, but it also supports the other position, depending on exactly how you interpret the role of precaution in environmental decision-making. [Slide 56] Some of the most fundamental ethical questions about solar geoengineering concern humanity's relationship to the natural world, and this concern comes in at least three different versions. With respect to the first version, decades of work in environmental ethics generally counsel us to reduce our interference in the natural world. Deploying solar geoengineering would, at least in some sense, intensify our interference in the natural world, and so run counter to what we should be doing, on this line of thinking. I should say, though, that there is another strand of environmental thought, according to which we need to embrace the Anthropocene and accept the mantle of "stewards of the planet." It is less clear what that kind of thinking about our relationship to the natural world means for solar geoengineering. The second version of this argument suggests that deploying solar geoengineering would be transgressing some kind of boundary, overstepping our proper place in the cosmic order, if you will. This sort of concern is often expressed in religious terms by saying that "we shouldn't be playing God" by interfering with the climate. On a more practical level, that sort of concern about playing God or messing with nature often represents a fear that the climate system is simply too complex to understand well enough, and so intervening in it, tinkering with it, is just inviting disaster. [Slide 57] Almost all of the concerns that arise with deployment of solar geoengineering also appear in research and development of solar geoengineering. Some of the concerns about precaution, procedural justice, and intergenerational justice appear right at the beginning: Should we be doing this research at all? Will it undermine commitment to mitigation? Will it put us on a slippery slope to deployment? How should decisions about research be made? If the research were to progress to global field trials, almost all the other concerns about distributive justice, our relationship to nature, and so on, would also come in. Finally, as Pablo alluded to, that sort of experiment, a global field trial, would amount to experimentation on human subjects where the human subjects are all of us. That sort of research is normally subject to strict ethical guidelines that are very difficult to apply to this kind of research. Research into geoengineering—especially solar geoengineering—raises not only the kinds of ethical questions that apply to deployment, but also raises new questions. So thinking about governance needs to begin now; the research itself calls for governance. Whatever governance institutions we design or choose to govern research into solar geoengineering will influence—or maybe become—the institutions that govern deployment of solar geoengineering, if that ever happens. So we need to think now about how best to design those institutions. Fortunately, that is not a problem that I have to solve. I am going to leave that to Arunabha and Ted to tell us how to think about that. Thanks very much. JANOS PASZTOR: Dave already started with a question of governance, so let's get right into that. I can see Arunabha Ghosh, chief executive officer of the Council on Energy, Environment, and Water from New Delhi. After some technical challenges, it seems we are able to have you on, so you have the floor. ARUNABHA GHOSH: Thank you. [Slide 58] Good evening, everyone. This is Arunabha Ghosh from India. I'm sorry I can't hear anything on this webinar, so you will have to just bear with me. If you have any questions, if you could type them up, that would be great. I'm going to spend my next ten minutes just talking about why I think we need to have a more serious conversation about the governance of climate geoengineering. [Slide 59] I represent the Council on Energy, Environment, and Water in India. Among other things, we've been working on the governance of climate geoengineering since 2010. [Slide 60] Among other things, what we've been doing since 2010 and 2011 is hosting a series of conferences in 2011, 2012, 2014, and 2016 in India and outside to keep the conversation going about the emerging dialogue around climate geoengineering. But of course, the conversation has picked up pace in recent months, particularly in light of whatever is happening within the climate negotiations as well as in the broader spectrum of climate change research. [Slide 61 skipped]

Slide 62

The big message that came out of the Paris Agreement is that while it brought 195 countries together, if you look at that graph, we are clearly nowhere near where we need to be. That red line is somewhat where we've managed to get to vis-à-vis the Paris Agreement, slightly below the "business as usual." But if we are serious about keeping to well below 2 °C, we have to be somewhere along the green line.

[Slide 63] That raises the question of how quickly could we end up in a climate geoengineering world. I caught a little bit of the presentations from the previous session about the science around climate geoengineering. But if you look at it from the perspective of climate-related impacts, whether it is on the costs of agriculture, on the broad adaptation gaps that are resulting, the trillions of dollars that would be needed in our estimation just in developing countries for adaptation, or the broader climate risks across the world, we are increasingly entering a world, whether we like it or not, where extreme measures might be required.

[Slide 64] So the Paris Agreement actually was kind of a once-in-a-lifetime situation where climate scientists, climate technologists, and climate negotiators came together to create the framework for a broad agreement. But now, if, say, the United States withdrew, or stayed in and went slow in terms of the negotiations, you are left with the climate scientists and technologists rather than climate negotiators who can keep the ball moving forward in terms of trust with regard to climate action, which, to my mind, keeps increasing the motivations or the incentives, whether rightly or wrongly, for more extreme measures. [Slide 65] That raises the question of what kind of governance would emerge or would be required for climate geoengineering activities. [Slide 66] I would like to focus a couple of minutes on this slide. When we think about climate engineering, it depends on where we sit. If we are a group of scientists promoting research in this area, we would presumably want a governance structure that maintains maximum flexibility for us, whereas if we were, say, an NGO or a country that is opposed to climate geoengineering, our major material concern would be to constrain others. The same applies to ethical concerns, whether it is about the moral hazard associated with research on climate engineering; whether it creates incentives to go down that route; whether it creates the problems of how to establish legitimacy and accountability for any kind of actions taken. That will then influence the kind of governance arrangement that we get; whether we are making decisions on what kind of research has to be funded or what kind of activities have to be permitted; whether it is related to governance arrangements for monitoring the actions; it could be laboratory research; it could be field tests; it could be deployment at a later stage; or it is associated with governance arrangements relating to resolving any disputes that might arise. You can see that depending on where you are, whether you're a proponent or an opponent, whether you're a rich country or poor country, or you're facing the impacts of climate geoengineering activity, or you are seeking further intervention because you're affected by severe impacts of climate change, the rules, the norms, the procedures, and the customs around the governance will keep varying. [Slide 67] The question then is: Is national governance going to be enough? You can think of various scenarios in how this could play out. In one scenario, you could have only privately-funded research going on. In a second scenario, a small group of countries could decide to collaborate on, say, field experiments. In a third, research groups in several countries could get involved. In a fourth scenario, one large economy could decide that it is in a situation where it decides to act unilaterally. In a final scenario, you could have even a very small economy, or even a small island state, for instance, which is facing the vulnerabilities of climate change, and its only asset is its sovereignty, and it welcomes scientists from elsewhere, saying, "Come and use my territory to undertake research in this area." Any of these scenarios then raises the question of whether national governance would be enough. In some it might be, perhaps in scenario one. But in most others, you're already entering into a world where there will be trans-border impacts, whether it is in the form of the atmospheric impacts or in terms of political impacts or consequences. [Slide 68] This then raises the question: Do we have any international governance forums through which this kind of activity can be governed? Unfortunately, we don't have a single forum as yet, but there are several different treaties, conventions, etc., which might have some applicability to climate change engineering research and deployment. Some are applicable to all geoengineering methods, for instance, whether it is under the Environmental Modification Convention (ENMOD), which is a dormant treaty but could be resurrected, or the Convention of Biological Diversity (CBD), which in fact imposed a moratorium, or even the FCCC Convention. Some might be applicable to specific methods, say, the Montreal Protocol being used to govern the injection of stratospheric aerosols, or the International Convention for the Prevention of Pollution from Ships (MARPOL) for marine cloud brightening, and so forth, or some could be restricted to specific types of geographies, such as related to the Outer Space Treaties or the marine environment. Any of these give you a flavor that there are international conventions, treaties, and protocols that could be used to govern, or it might raise the question that they are not sufficient overall, and therefore we need something different. [Slide 69, Slide 70] To me, the big question is: If we have to design a governance system, then we have to begin a serious consultation with the public at large, not just among a very small community of researchers or a small community of climate negotiators, and that consultation can take very different forms. The first is what we could call "public information," which is just simply one direction or flow of information from the proponents of any kind of research activity to others who might be impacted by it. A public consultation is slightly different, where we just get the feedback from the participants or those who are going to be impacted back to the proponents, but there is no guarantee that the consultation is going to result in anything. Then there is public participation or deliberation, which is a bidirectional conversation that goes on, and is not time-sensitive. But that raises the question, what if the public at large or the community impacted decided to say "no"? What kind of governance systems would then be applicable for dealing with that kind of a situation? [Slide 71] The other big governance question beyond consultation is if we had to restrict our governance arrangement only to the design of research programs, then can we learn some lessons from how internationally-coordinated research has happened in the past?

That would require thinking about the governance arrangements that draw in research capacity for different kinds of countries placed in different economic levels or with different scientific capacity, and how that can be pooled together to have a research capacity base that is fit to purpose. The second design element is how do we bring in the funding. Would it be funded only by one set of countries, or would it be in-kind contributions or cash contributions? There are examples, such as in agricultural research how donors and researchers in developing countries have balanced their funding responsibilities. Then comes the issue of liability. In the European Organization for Nuclear Research (CERN) platform, we have explicit clauses where research creates international liability for the participating countries. There are also flexible options available in regard to the disposal of radioactive waste. So you can design different kinds of liability clauses depending on what scale of research you are undertaking. Then there is the question of who will share the intellectual property, and how easily would data be accessible. Again, there are a number of examples where even research data or results restricted to a few countries have then been transferred or made available more widely. Then there is institutional design. You need a formal agreement between the participating players, or can a voluntary arrangement suffice? [Slide 72] To me, the real question, then, when you're designing governance, is around consultation, around designing research programs, but also, finally, about identifying who are going to be the stakeholders; do we have any kind of framework to determine who should be involved in this conversation? That slide, while it looks complicated, basically tells you that if you were a scientist, there would be a range of other stakeholders who might have a view on the kind of activities you undertake. Other scientists might say, "Well, we are going to peer-review what you're doing." If they are private investors, they would say, "Well, we're looking at a return on investment." Climate negotiators might be looking at the governance arrangements for research. Governments or legislatures might be looking at the return or the oversight of publicly funded research. Equally, if you were an international organization, then scientists might tell them, "Don't impose a moratorium upfront," or if you are a negotiator, then you would use the international organization platform to constrain others while keeping maximum flexibility for yourself. This slide effectively tells you that designing this governance arrangement, if it has to be legitimate, if it has to be inclusive, and if it has to draw on lessons from the past, is going to be quite a messy affair, which means you've got to stage the governance design. [Slide 73] The real message I'm trying to give here is that the Paris Agreement has changed how we look at technology development. It has created new platforms for public-private research, but it might have also opened up the world for climate engineering. If we are serious about what the agreement asks us to do and we look at how countries are behaving currently, we might be ending up in a world where the research into climate engineering becomes more of an inevitability, even though we don't know whether it will be a successful set of technologies or not, which then raises the question that we need to look at climate science and climate technology research and climate geoengineering research as a continuum and design governance arrangements accordingly. So can there be a progressively inclusive approach to solar geoengineering governance? I would recommend that we at least start with national-level scientific assessments as have already occurred in Europe and the United States but should occur elsewhere; national-level stakeholder consultations to understand the perceptions toward these, and there are research programs that have begun to do that; national-level policy-making and legislation, at least to govern activity that is happening within one state's borders; then, in the minimum, some degree of voluntary reporting on what different activities or different arrangements of coordinated research, whether it is within a country or between a few countries, to some international forum. Then we need a degree of independent peer review and oversight to create new mechanisms of what we could call "public-private covenants." And finally, at a much later stage maybe, look at the much broader set of stakeholders to create maybe a plurilateral intergovernmental registry or reporting or accountability. These are at least the minimum steps that would be need to be taken to balance the material and ethical concerns, to balance the need for flexibility for one's self and constraining others, but also to recognize that climate geoengineering research is not a kind of monolith, and as the research evolves the governance has to evolve simultaneously. You can't be too governed in advance, and you can't be completely a laissez-faire story with zero accountability. Let me stop there. I look forward to questions that are sent in in writing. [Slide 74] Thank you.

JANOS PASZTOR: Thank you very much, Arunabha. We will try to make technology work so you can hear somehow our questions or at least get them to you. With that, let me now turn to our last formal panelist, Ted Parson. You have the floor, and you will continue on governance issues. Thank you very much. TED PARSON: [Slide 75] Thank you and good morning. I understand we're a little short of time, so I will try to be brief. [Slide 76] Much of what I have to say about governance challenges and potential responses for solar geoengineering is closely related to comments some of the previous speakers have made, so I will try to highlight different aspects or different perspectives on them. First, I would like to note that the most prominent governance challenges related to solar geo can be inferred quite directly from a set of structural properties of the technologies. Admittedly, these characterizations are based on relatively early research about the technologies, but there are many indications that they are likely to be robust. Solar geoengineering interventions connect fact over a period of about one year or so for starting to have an impact, for controlling that, and for terminating that. Many of the proposed scenarios for how they might be beneficially used principally are consequences of this capability for fast action. In terms of the direct cost of deploying them, which of course is not the total cost of a program, they appear to be very cheap. That might be perceived as a good thing or a bad thing, depending upon who you are imagining might take advantage of their cheapness and for what purposes. Of course, all solar geo interventions can at best only be imperfect and partial corrections to the environmental harms of elevated CO2. The broad implications for governance come from these structural characteristics. To sum those up, we can identify a couple of highlights. First, it is possible that solar geoengineering interventions may be able to substantially reduce the climate change risks that the world faces. It is not merely that they cannot be substitutes for mitigation or adaptation, but it is also at the same time that they can do things that mitigation and adaptation cannot, and so they may represent a real prospect for advance in global benefit in managing risk of climate change. Even more strongly, it appears more and more that substantial use of climate-engineered interventions—large-scale carbon removal or large-scale use of solar geo or both—may be the only feasible ways to achieve the ambitious and precautionary climate targets that have been articulated at Paris—the 2 °C target and even more strongly the 1.5 °C—and of course, with each year that passes as global emissions tick on and add their 40 gigatons to the total cumulative budget each year, it becomes even more tight and constrained a problem, and so, more likely. On the other hand, solar geo interventions carry new and potentially serious risks; risks of direct environmental harms, and risks that may be even more severe that one might call sociopolitical risks related to how they might be used or misused. If we try from the perspective of current knowledge to add this all up and say, "Well, should they be developed and pursued and investigated? Are they more likely to help us or hurt us?" the only fair answer is, "We really don't know" because they have large capacity for either good or ill, depending upon the conditions and the terms of use. Add that all together, and it means that two things are broadly needed: First, it is necessary to understand better what the interventions might be and what they might do, and that is primarily a matter of research. Also, equally crucially, it is necessary to understand better the likely and the possible conditions for development of use that would determine their consequences as actually applied. [Slide 77] Stipulating that what is needed is a basis for well-informed decisions about climate change, about strategic response to climate change, and about the place or non-place for solar geoengineering interventions within that, there are a couple of needs that are related to solar geo. As I've mentioned, it is necessary to pursue, and to pursue with more vigor than previously, research into methods of solar geoengineering, their likely effects; both beneficial and harmful, intended and unintended. The way to do that is to pursue a program of further research that would involve more of what is already done—integration of solar geo into climate model scenarios—with more realistic characterization of what methods would be used, and of scenarios of their use in the context of different trajectories of climate development and other responses, and also consider more of the impacts. It is also necessary to move to a field test to calibrate and test effects more precisely. Of course, as I'll get to more in a moment, it is also necessary even in conjunction with early moves to expanded research to have governance structures in process to handle any risks or challenges in the social or political sphere that might arise from that. In addition to research, it is necessary to do assessment of solar geo interventions: assessment as activities that synthesize and interpret and evaluate what's being learned from research; that articulate their meanings in terms that are relevant for decision-makers; and that also reflect back upon a research agenda to give guidance about priorities for what further information is needed from research. Assessment is needed about the feasibility and effectiveness of specific solar geo interventions. There has been a fair amount of discussion early on about how that might be best managed to suppress or deflect reasonable concerns that advocates of one method or another might try to bias assessments to a promotional outcome. There has been some suggestion that the way to do this is to use something like an adversarial system from legal proceedings where one team is charged with demonstrating how some method can be made as good as possible, and another team is charged with finding all the weaknesses or problems or flaws associated with it. We also, of course, need assessment of direct environmental risks. In that, as I suggested a moment ago, even if the research agenda is beginning, there is still a need for assessment at the same time, because assessment both draws out the implications of what we currently are getting from a research agenda and reflects back to the research agenda to provide priorities for further work. Finally—and this is really the crux of the problem—we need assessment that examines those risks that are not direct manifestations or consequences of technological characteristics or of the environment in which they operate, but that are dependent upon how the technologies are used or misused. It is this character of risks that so acutely identifies the need for governance of solar geo interventions. I am going to address the major governance challenges in kind of the opposite direction from what Arunabha did. He provided a great deal of detail on the various conditions that would inflect early steps of governance related to development of solar geo research. I am going to go to the other end and kind of think ahead to the prospect of a future world in which nations or other actors are actually proposing to conduct operational solar geo interventions, think about the governance challenges and the requirements for effective governance methods and processes that those imply, and then reason back from that. [Slide 78] What do I mean by "governance challenges?" Let me identify a few top-ten greatest hits: There is the problem of control. Because solar geo interventions have such low cost and high potency or leverage, in principle the capability to deploy them could be widely spread. Some early writers suggested that even non-state actors might be able to deploy solar geo. More recently it looks clearer and clearer that that is not the case, but there are probably still a dozen or two dozen nations that would be in a position to deploy if they wanted. Governance means somehow getting that under collective control at the international level. At the same time, governance poses the challenge of saying, "What would comprise a legitimate process for decision making about whether such interventions were used, when and how, and under what conditions?" It is sort of obvious that there is a need for a legitimate decision process because the effect of these interventions cannot be controlled; they are worldwide. Even more challengingly, it isn't just that using solar geo is an on-off switch. The decision ever to use it is also a decision about how to use it, and the more closely it is investigated the more it appears that there might be multiple dimensions of potential control that would have some effect on differential impacts. The next governance challenge: Holly and others have mentioned the moral hazard problem. Any decisions that are made about solar geo and its use would obviously be closely interactive with decisions that are made about the other aspects of climate change and climate response. There has been a great deal of discussion about the risks that those interactions are perverse, and so the consideration of one undermines the others. It is also possible that you might want to investigate how these interactions can be made constructive and mutually supportive, defining decision agendas so that the presence of climate engineering or solar geoengineering actually enhances prospects of mitigation.

Simply to give you a flavor of other governance challenges, if there is ever a decision made to use it, that wouldn't be the end of it. There would have to be competent technical oversight, and so there would have to be institutions charged with the authority to do that somehow under an international political authority. If it was ever used, there would need to be determinations of what you do when someone charges that harm is done, and so issues of liability and compensation. There would have to be some international process to avoid and manage any conflicts that resulted from disagreements or charges over the use of these things. Stepping back to the near-term issues, the ones that Arunabha highlighted, in order to move toward a system able to handle these longer-term governance challenges it is necessary to think very carefully about how to put governance institutions in place in conjunction with early research programs in order to avoid unintended commitments to continuing a program without reflective, thoughtful decision-making, and in order to avoid damaging early missteps that might impair the ability to do effective governance later. [Slide 79] Finally, there has been relatively little discussion of these challenges so far, and there has been none in any authoritative international body, partly because the questions are so daunting and because our thinking on them is so early. People have to some extent been afraid to talk about these, and that is a reasonable fear. If you pose the questions, "Who should be talking about this?" and "How should this conversation take place and where?" the conditions you would want to begin a process of international deliberation on this are rather demanding. You want broad international representation with high-level expertise in international affairs, but you also want people who are not carrying briefs and immediate interests in decisions because we don't know what the necessary institutions and processes would look like. You also don't want the conversation to be driven by scientific issues because it really is a matter of political possibility under evolving political conditions. Arunabha alluded to the fact that there are many current international institutions that have responsibilities of some relevance to the governance of solar geo. That is correct. It is also correct that there is no current body that has the blend of capacity and authority necessary to act on it. I would also submit that there is no current body that is well-suited to be the place where these early high-level deliberations over what is needed in governance start. The FCCC is not a good place because it is an authoritative, decision-making, and negotiation body. What is needed right now is an open, expertise-informed exploration that doesn't press to early decisions. The IPCC, although it is well-suited and has a responsibility to press forward the assessment agenda related to solar geo, it is not well suited as a place to explore the governance agenda because the governance agenda is not principally of scientific character, and the debates aren't ultimately to be resolved based on scientific authority or reference to peer-reviewed literature. I am not going to sketch the details of a proposal that I think is promising for a first step because I am out of time, but I want to simply raise the term, "A World Commission on Climate Engineering," might be a near-term, feasible body that could be established within a couple of years that would support the kinds of deliberations that are necessary to advance understanding on how to solve these acute, long-term governance challenges. [Slide 80] Thank you. JANOS PASZTOR: Thank you very much, colleagues, and all the panelists. I think the first question I'd like to throw out is to David. The question that came up is: How do you compare the ethical issue of basically letting people be impacted and die because of present climate change practices versus potentially having negative impacts of climate engineering? How do you deal with this ethical issue? DAVID MORROW: That's a great question. The shortest answer is that is something that is still debated in the ethical literature. The scholarship has gotten to what at least some people are calling "second-generation" thinking about the ethics of climate geoengineering, where that is precisely the comparison that you need to make, and that is why I wanted to emphasize that we are not comparing the effects of solar geoengineering to the present climate or an ideal climate, but to significant climate change in which people are suffering and dying because of those effects. The view that I've argued for in the literature is that we want to sort of weight the negative for positive consequences of this deliberate intervention a bit more heavily because it is deliberate, but that's something other people in the literature disagree with. JANOS PASZTOR: Thank you, David. Let me throw out an easy one to Arunabha. Can you consider solar radiation management to be compatible with the UNFCCC Protocol Article 2? ARUNABHA GHOSH: I'm blanking out right now, Janos. I have to look up my Convention and look at Article 2, but if you want to remind me. JANOS PASZTOR: It is the most fundamental part of the original UNFCCC about the protection of the atmosphere from anthropogenic negative interference. ARUNABHA GHOSH: So your question is whether this is compatible with that article? Is that the question? I'm not an international lawyer, but I would think that there are different interpretations that could be made for it. If we take any intervention that is already happening and say that the Convention is permitting a degree of scaling down because we are deliberately intervening, and that is the basis of various protocols and agreements that have come about so far, then even climate engineering can fit into that. If you take a more literal view that absolutely no intervention is possible, then of course it is incompatible. But I would leave it to international climate lawyers to comment on that rather than myself. JANOS PASZTOR: Ted, you may have a thought on that also. TED PARSON: Yes, absolutely. If you emphasize the passage "prevent dangerous anthropogenic interference with the climate system" from Article 2, that is precisely the aim that solar geoengineering seeks to advance. The one wrinkle is its compatibility with the other language of the Article that concerns explicitly the limitation of concentration of greenhouse gases in the atmosphere. In a sense, you can think of the language of Article 2 as embedding a causal model of how human activity contributes to climate-related risk, or might be able to mitigate climate-related risk, but it is a causal model that solar geoengineering means is no longer valid. With solar geoengineering there is an additional possible tool to limit dangerous anthropogenic interference with the climate system. It is difficult by counterbalancing one form of interference against another form of interference where they are not perfectly targeted, but it is a mode of aiming to reduce dangerous anthropogenic interference that does not depend upon the reduction of greenhouse gas concentrations in the atmosphere. In a sense, carbon cycle interventions of climate engineering are more obviously and readily compatible with Article 2. On the other hand, solar geo may be more effective, or effective in different additional ways, at limiting dangerous anthropogenic interference. JANOS PASZTOR: Thank you. I would like to throw out a question, and while you think about it, I will ask Will Burns to say a few words. The question is to a number of you: This governance system, elements of which are being proposed, it is just too complicated, too complex, and we need something quickly. Can you address that? Maybe we could start on a regional basis, somebody proposed, if you could try to address that. But before you do that—just think about it—I would like to ask Will to say a few words. WILL BURNS: Okay. Thank you very much. Just very briefly because I know we're running out of time, just a couple of observations in terms of the interventions in this panel. First of all, I thought Holly did an excellent job of outlining why public deliberation is important in this context and some of what we've done to date. Some of the other challenges that I would highlight in terms of moving forward in this are, first of all, how do we include the most vulnerable in developing countries in these public deliberative processes given the fact that they are both disproportionally impacted by climate change and might be disproportionally impacted by interventions associated with climate geoengineering? Another challenge we have is including sectors in both developed countries and developing countries that don't traditionally engage in public deliberations, fortifying the democratic model by including these people. Another challenge that we have in terms of framing these issues is often these studies to date have been Manichaean in orientation; they have said, "Either we proceed with unabated climate change and the potential implications of that, or we have climate geoengineering interventions." We know that it is not that simple from a policy-making perspective. Realistic public deliberations have to include the possibility of rapid decarbonization interventions, and we need to discuss what the opportunity costs are associated with doing that, and the risks, and include all of these in a portfolio of potential responses that should be considered from the standpoint of deliberation. In terms of Arunabha's discussions, and Ted's to some degree, I would highlight that while we need to look at all of those regimes, there are also non-environmental regimes that may be extremely important from the standpoint of geoengineering governance. That includes regimes associated with intellectual property, for example, because there will be intellectual property considerations—we know that already from the Stratospheric Particle Injection for Climate Engineering (SPICE) experiments—and also human rights regimes because some of these interventions potentially could affect the right to food, the right to life, right to health, etc. Those need to be taken into account, and Paris calls for us to look at human rights considerations in any case where we look at response measures. Finally, in terms of the discussion of whether geoengineering is a way to meet Paris obligations, I think that is a difficult question. If you look at the nationally determined contributions (NDCs) under Paris and the discussion of meeting them through mitigation, traditionally we've defined mitigation as a "means of enhancing sinks and ways of reducing greenhouse gas emissions." Whereas Article 2 might be construed as permitting SRM interventions, I think that one could not arguably meet one's NDCs through the use of geoengineering. That doesn't mean that it might not still be utilized, but critically, it probably at this point is not one of the ways that one could fulfill one's NDCs. So if we are going to go down this path, we might need to amend the Paris Agreement to encompass that vision that Ted spoke about. Thank you very much. JANOS PASZTOR: Thank you very much, Will. Now I'd like to turn to Ted and Arunabha in particular about complexity and what we can do about that. TED PARSON: Shall I take a quick stab at that? Yes, absolutely. The governance challenges that arise from the structure of effect and the potential distribution of costs and benefits of solar geo interventions are very severe and complex and daunting. Indeed, some writers on commenting on these governance challenges have quickly reached the conclusion that governing these interventions is and always will be impossible, and thus it is improper, or wrong even, to investigate or research them. In my view, the challenges are complex and daunting, and it will take a while to develop the governance capability that is needed. But there are near-term challenges related to sensible construction of governance arrangements around near-term research that are much more feasible, and there are near-term ways to approach the bigger, longer-term questions, such as the world commission that I suggested. We need senior, experienced, broadly representative minds considering these problems and considering them in the context of the changing political conditions that absolutely will be upon us as climate change progresses and impacts grow more severe. Things that appear today to be too complex, or even politically impossible, may not be so under those more rigorous conditions. JANOS PASZTOR: Arunabha, do you want to comment on that, too? ARUNABHA GHOSH: There is no question that the issue is complex and daunting, but it looks more complex and more daunting if we think about governance as one monolith and a kind of binary—whether you have covenants or you don't have covenants . The point, I think, many of us have been making throughout the session is that it has to evolve as the research progresses. You can't have a Harry Potter theme park until the book has been written, but you could have something along the lines of how you are going to actually assess what is being written, how it is being written, and who is writing it, before we get to a much larger platform where a bunch of people—negotiators or representatives—are able to call the shots. That is why, I think, whether it is a world commission that Ted is proposing that begins to assess everything that is going on currently, or matching that sort of quasi-top-down framework—even though it need not be intergovernmental—with something bottom-up, which is what I was suggesting, let at least those 20-odd countries that might even have some degree of technical capability of engaging in this, all do a degree of national assessment. Let the national assessment not just be restricted to something that the U.S. Congress undertakes or something that is undertaken in Germany or by the British Parliament. Let India, China, Brazil, others, come up with their national assessments. Let there be some degree of voluntary reporting, but under sort of a common framework, templates, etc., to maybe this world commission or whatever is happening within national borders. Then let there be a meeting of minds between this kind of voluntary reporting, a degree of third-party peer review, along with a commission of elders that begin to assess what is going on and get a much broader view, not just of the science but of evolving governance templates in different countries, what different legislatures are saying, which gives us a flavor of what an international governance mechanism might eventually look like. I think it can't be just a top-down or a bottom-up model, or something completely devoid of the governments and just a body of elders. We've got to play this out with those different sets of stakeholders, but giving each stakeholder some kind of a role, maybe not under one umbrella, but a feeling that they have a say within national governance frameworks, with national public consultations; they could have a say through international platforms; or they could have a say through third-party peer review. Let's build it as we go along and not expect a set template to be ready for us overnight. JANOS PASZTOR: Thank you, Arunabha. I have a quick and simple question to Holly and maybe to Will, depending on how she answers it: Often we refer to the global public that will be affected by solar radiation management. How do we define that, and how do we handle the global public in terms of public participation and so on? HOLLY JEAN BUCK: Yes, I think that the expression is problematic in some ways. I think it is better to recognize many publics are distinct publics. People have differentiated vulnerabilities, both to climate change and possibly to climate intervention. There is a political theorist, John Dryzek, who talks about having a "chamber of discourses" and having, "in our different discourses are many publics represented." I think maybe that is one way to look at or approach the issue. Maybe Will has more to say on that. WILL BURNS: I would agree with that. I think I would emphasize that the perfect should not be the enemy of the good; that we're not going to engage in public deliberations to get a definitive answer or believe that this will be wholly representative of world public sentiment, but rather we use public deliberations as both a means to educate the public and to get some sense of various publics and their attitudes on these issues in a way to engender more discussion, and hopefully a process that ameliorates the impacts and emphasizes the benefits in the longer term. JANOS PASZTOR: If we can look at it at the global level—I know there are, of course, very clear differences between different countries on this—but are we closer to educating the public as opposed to engaging and participating—real participation—in decision making? Can either of you address this? Arunabha? ARUNABHA GHOSH: I think we've got to understand the extreme circumstances under which we are even considering this. There is a dissonance between that kind of a conversation and a conversation that has been sold to publics at large, especially, say, in the lead-up to the Paris Agreement, that one way or the other, if we do a little bit here or there, do some solar, renewables, energy efficiency, and so forth, we create an atmosphere of trust, feeling good about our actions and domestic policies, and we get to a Paris Agreement. But the reason we are having this conversation is because we recognize, at least in our limited community, that this is clearly not enough. So the public conversation, whether it is a consultation or just a unidirectional flow of information that you are talking about, is really going to be still a very difficult one because you are going to have to sell a very different story. You are going to have to tell them that everything that you are doing is still nowhere near enough, and that is going to require a different degree of political leadership and a recognition of the impacts that especially the poorest communities are already facing. Connecting that to climate change science and then climate engineering-related research is going to be a tough job for the best of communicators, but that is the challenge we have before us. JANOS PASZTOR: Thank you very much. The last question I have on my list was a fairly interesting, practical one: Is there a database of activities that different people and institutions are doing in the atmosphere on climate engineering? Is there one? Should there be one? Any responses to that? WILL BURNS: "Are doing in the atmosphere." So the question presumes that people are doing climate engineering things in the atmosphere. I believe the answer is, "No one is." The few attempts or proposals to undertake—there are a couple of odd experiments that have been done at small scale, but far more that encountered controversy or were stopped or have not yet succeeded in going forward. So while such a database would be an excellent idea if and when active field research programs related to climate engineering start, at present I believe the contents of that database would be empty. JANOS PASZTOR: Thank you. With that, I think we've run out of time. I would like to thank our panelists. Unless any of the panelists have some important last words that they would like to share with the audience, I would like to ask Simon to join me and give a big thanks to everybody for this webinar. If I don't hear otherwise, then thank you very much to the panelists, Ted, Holly, David, Will, and Arunabha. Simon, I think we have come to the end of this webinar. It has been my pleasure to work with you, to work through these last two-and-a-half hours. We were a few minutes delayed at the end but not too bad. I thought that the discussion was very interesting and very helpful. Lots of interesting questions, some of which can be followed up afterward in more detail also. I understand that there will be a recording of this available for those who registered, so they will be able to come back and look at this again. There was one other question that I had not put to the panel: When are we doing one on CDR, carbon dioxide removal, something like this? We had not planned to do one on that, but I am aware of an international symposium in Utrecht, Netherlands, in June on that topic, so maybe those who are interested can already start looking at that. With that, I would like to thank everybody, particularly the people who you don't see behind the scenes, Natalie, Kai, Nicholas, and Michael, who were all making these things happen. Thank you very much for that. Thank you for all the participants who are still connected. I think at the maximum we had over 60 participants connected, so that is pretty nice. Thank you again. Simon, maybe you can say a few last words, and then we close. SIMON NICHOLSON: The final thing I'll say, Janos, is that what this webinar shows is that there is a very vibrant research conversation, and this research conversation is throwing up lots of questions that can only actually be answered by policy and public engagement. This conversation needs to get broader. The reason that we run webinars like this is so that we can bring new voices and new perspectives into an area of research and thinking that is actually growing in importance for the reasons that we heard from various speakers today. Thank you for reaching out and offering to do this together. I know that there will be opportunities for more outreach of this type. JANOS PASZTOR: Thank you very much, everybody. With that, our webinar is over. Thank you for your participation, and goodbye. SIMON NICHOLSON: Thanks, Janos.