Engineering Our Attitudes
How Geoengineering Can Inform Our Perspective on Climate Policy

Good morning, it's a pleasure to be here. Unlike most speakers here today, I'm not a scientist or an academic, I'm a student of the policy implications of geoengineering, having worked on climate policy questions at both the state and federal level. I'm going to talk about why we should study geoengineering, why I believe objections to research are misplaced, and why I think the idea of geoengineering itself is potentially an important component to a new approach to the climate challenge.

To start, though, I want to talk briefly about the larger picture of climate policy today, because you can't separate geoengineering from its climate policy context.

2009 was an extraordinary year, obviously, for everyone working on climate. A year ago, ambitious new federal emissions limits were widely expected, and many thought that they would be followed by negotiation of a new international climate treaty at the Copenhagen conference in December. We all know how that worked out. Today, I think it is clear that no federal cap on emissions will be enacted this year, or even, for that matter, during President Obama's first term.

Today, I think it is clear that no federal cap on emissions will beenacted this year, or even, for that matter, during President Obama'sfirst term.

The international picture is similarly discouraging. The Copenhagen Accord, which is nonbinding and may be unraveling, did produce pledges from many key nations to reduce their emissions. But these promises fall far short of what would be necessary to limit the temperature increase to 2°C (3.6°F); even if these promises are kept--which seems unlikely--the Copenhagen commitments would still allow global mean temperature to increase by 3.9°C (7.0°F) by the end of the century.

Funding for adaptation measures appear to be similarly inadequate. At best, the Copenhagen pledges will allow us to ameliorate the effects of 1.5°C of warming, leaving 2.4 degrees unabated (if projections are correct).

So, the picture is clearly worrisome. We are, I think, seeing the gradual collapse of the longstanding policy framework for climate, the Kyoto architecture, as well as any hopes for a similar policy in the US in the near future.

The question now is whether new ways of thinking about the climate challenge may emerge from this wreckage. It's not clear yet whether the environmental movement is capable of such a dramatic re-imagining of its agenda and methods--but I hope it is, and I think geoengineering may have an important role to play, both practically and conceptually, in that process.

A few observations about the way we think about the climate challenge, because I think we have framed the issue in the wrong terms. Many people see carbon dioxide as merely another form of air pollution, albeit on a grander scale. It's not; carbon is different. Three points to consider:

  1. A near-zero emissions future is possible--but it is likely to be a long time coming. Fossil fuels are used to generate more than 80% of the world's energy; and the options we have for replacing them or capturing their greenhouse gas emissions are relatively expensive, if they exist at all. Energy transitions, historically, are very slow and uncertain processes, and I see no sign that we are on a path towards a more rapid transformation today, despite our desires to the contrary. Worldwide energy consumption is expected to increase 50 percent from 2005 levels by 2030, with the bulk of that growth coming from developing countries, and realistically, I do not expect much of that energy to come from low-emission sources.

  2. The warming produced by CO2 is, in effect, irreversible, since CO2 and its warming effects persist for centuries. In other words, absent geoengineering, substantial warming is already "locked in." We have simply never encountered a pollutant that was both so persistent and abundant, and this accounts for our misunderstanding of the nature of the challenge. Carbon dioxide is simply not a conventional pollutant, it has unique characteristics that demand unique policy responses.

  3. We don't know what that means for us; we might be all right, we might not. The complexity of the climate system means that we cannot eliminate a frightening degree of uncertainty about tipping points and feedback loops, and despite decades of research, our understanding of climate sensitivity remains uncertain. Scientists continue to debate what level of greenhouse gases would be "safe"; if you agree with Jim Hansen and others who believe that 350 ppm is the right threshold, the inescapable implication is that some very innovative approaches are needed since we've already reached 390 ppm and, obviously, show no sign of stopping there.

One of the things that makes climate policy so difficult is uncertainty. There's just a lot we don't know about what lies ahead. That uncertainty, at least in part, contributes to the political inertia we see today, but it also emphasizes the need for policies that give us options for managing these risks.

Some of you may be familiar, for example, with the work of Harvard economist Martin Weitzman, who has written about the importance of paying attention to the "fat tails" of the climate risk curve--that is, the 5 or 10 percent chance that something truly catastrophic may happen. He has a good point, of course--and to be fair, his argument is that we should pay more attention to mitigation--but given how slowly emissions reductions take effect, and how ineffectively we are pursuing them, Weitzman's logic clearly suggests that we should think seriously about other ways of dealing with these dangers, because if they are real, mitigation alone is probably insufficient.

The implication of these ideas for geoengineering should be clear: Geoengineering potentially boasts a unique ability to overcome the inertia in the climate system and provide a degree of rapid cooling, if necessary. No other climate policy can make that claim, and that may be pretty important some day.

So, with that as a preface, let me turn directly to the question of why I think it's important that we have a serious geoengineering R&D program, and after that I'll have some thoughts on how geoengineering may provide an important and unique analytical perspective on this difficult problem.

Why Study Geoengineering?

The simplest answer is that knowledge, in this case, would be relatively cheap and potentially priceless, while continued ignorance of this field would be reckless, leaving the world needlessly vulnerable to potentially severe climate impacts, as I've just discussed.

Ignorance of geoengineering is dangerous for another reason, which should particularly concern those who are skeptical of geoengineering on its merits. If the effects of warming prove to be severe, it is likely that countries that are most vulnerable to warming (India, for instance, or perhaps the island nations) will want to undertake a geoengineering program. In such a scenario, it would be important to have researched this question thoroughly and developed appropriate governance institutions.

The United States, in other words, is not likely to be the first nation to seek deployment of geoengineering, but we do want to be prepared to take a seat at the table when that conversation occurs. Pandora's box has been opened; now, only greater knowledge, and international cooperation, can prevent its abuse.

Naturally, the idea of actually deploying a geoengineering system would be very controversial. But the narrower question of a research program should not be.

The complexity of the task contemplated by climate engineers, and the consequences of success or failure, suggest that we have no time to waste before organizing a research program commensurate with the scale of the challenge it aspires to meet. Even those who most fear geoengineering's potential side-effects should favor a rigorous research program to explore those questions now. And, I should add, I am reasonably optimistic that Congress will provide funding for such a program relatively soon.

Before I go on, I want to just take a moment to clarify my terms and make some distinctions that are important to the issues I'll take up from here on out.

The term "geoengineering" is unfortunately so broad that it encompasses a range of ideas that have widely differing characteristics, in terms of their risks, costs, scalability, efficacy, and so forth. As a general matter, geoengineering techniques can be grouped into solar radiation management schemes (SRM) and carbon dioxide removal (CDR) techniques, but even within those categories, there are important distinctions. Proponents of air capture, for instance, may be skeptical about other large-scale sequestration schemes such as ocean iron fertilization.

More fundamentally, most concerns about solar radiation management schemes, for instance, are irrelevant to most forms of biological sequestration and air capture, so it's difficult to talk about this field without over-generalizing.

So, we have good reasons to research geoengineering. Are there also reasons why we shouldn't?

Moral Hazards

There is one serious argument against even researching geoengineering, (or, at least SRM methods), which is the so-called moral hazard argument, the fear that greater consideration of geoengineering's feasibility might lead people to conclude that it is a viable alternative to mitigation. I find this argument flawed on several levels:

First, while I recognize that the argument is about perceptions, it is nevertheless important to be very clear about the merits of the idea: Geoengineering should be seen as a complement to mitigation and adaptation, not an alternative.

See, for instance, Tom Wigley's classic 2006 Science article outlining a combined geoengineering/mitigation strategy.

The reason is simple: These techniques are highly imperfect measures, at best; geoengineering offers tools that may contribute to climate solutions, but they are clearly not the solution itself. These techniques may cool the planet, but they will do so imperfectly, and not without risking potential side-effects. Some effects of emissions are unaffected by SRM, such as ocean acidification.

And, of course, if you see geoengineering as a permanent solution to climate, you are committing yourself to an indefinite future of ever-increasing reliance on that technique, a frightening prospect.

Setting aside the substance of the issue, there is the question of perceptions: Even if geoengineering should be rightly seen as a complement to mitigation, not an alternative, will it be seen in that light? I believe it will.

It is true that a handful of writers, perhaps seeking notoriety rather than wisdom, have argued that geoengineering may be an alternative to emissions reductions. I frankly have a hard time taking this idea seriously.

It has always struck me as implausible that any national leader would argue that geoengineering offers a safe alternative to emissions reductions--or that the American people would go along with the idea. Such a claim would require an extraordinary--indeed, I would say unobtainable--level of confidence in an unproven and manifestly imperfect technology.

In fact, I have long believed that most people, when told about geoengineering, would be more inclined to support greater mitigation, not less, thinking: If such extreme measures are really being contemplated, surely we ought to be more aggressive in our pursuit of other solutions.

Imagine, for instance, you were unable to control a potentially serious medical condition through diet and exercise--you want to, but lack the willpower or the workout equipment you need--so after a while, your physician prescribes a medication that carries the risk of serious side-effects while only treating some of your underlying condition. Wouldn't you redouble your commitment to diet and exercise?

In fact, focus groups held in England as part of a study commissioned by the Royal Society seem to confirm that hypothesis, with participants--particularly self-identified climate skeptics--reporting that consideration of geoengineering would be a galvanizing factor, not a cause for complacency, on their part. This evidence may not be conclusive, but it certainly is credible.

A final point on this question: As I noted before, Pandora's box has already been opened; people know about this idea, the moral hazard already exists. The question is whether further research in the field might actually lessen the moral hazard risk by revealing the true limitations of these techniques.


OK, so it would be prudent to research geoengineering, and foolish not to. But what about the policy context? Where does geoengineering fit in?

Perhaps the most important, and I think least appreciated, implication of geoengineering is the potentially revolutionary impact these technologies have, not upon the environment itself but upon the way we think about these questions.

Geoengineering can be a very helpful analytical tool to clarify what people's true goals and values are, and to expand the scope of our understanding of our relationship to the Earth's ecosystems.

One reason you see such strident opposition to geoengineering from some quarters is not that geoengineering won't work--it's that people fear it will work, and they don't want us to have other options; they cannot conceive of any approach to the climate problem other than Kyoto-style targets.

That would be fine, of course--if Kyoto was succeeding. The question is whether the collapse of Kyoto and Copenhagen will prompt any reconsideration of these positions.

Our twenty-year quest for an international treaty regime has brought us little more than an unbroken chain of broken promises. Today, we find ourselves in what I see as a rather defensive posture. We want to preserve the past, when reality demands we turn to face the future.

To use another analogy: I have heard some people describe the global climate as a car speeding down a foggy road, out of control and heading potentially toward a cliff we cannot see. If you accept that analogy, I would say humanity has been crouched under the dashboard, trying to reach brake pedals that don't seem to work. Geoengineering invites us to sit up, look ahead, and realize that there is a steering wheel, even if it's an imperfect one.

That isn't a solution to the climate problem--but it's a different posture in the seat, and that may make all the difference.

We are far from knowing which geoengineering techniques might work, but the very idea itself invites us to take a broader view of the climate challenge. As the evidence mounts that emissions reductions alone are likely to be insufficient, we are at least slowly coming around to the realization that we can't afford to ignore other tools, whether they're white roofs and biochar or cloud-based albedo modification.

The greatest determinant of our relationship to the Earth is not technology itself, it is our understanding of it, our way of thinking about how we use technologies. Technologies create opportunities for action, but it is humans who decide which of these opportunities to explore and what their implications may be.

We are told, for instance, that one reason geoengineering is impractical is that it offers the prospect of a global thermostat, but no framework for deciding where to set it. How can we expect billions of people to agree? But the point is, we should think about that question, and its many variations, whether or not we have the geoengineering option; it underlies the landscape of climate policy, but geoengineering brings it front-and-center.

What exactly is it that we're striving for when we set emission targets? Maximizing human welfare as measured by global GDP? Protecting ecosystem health? Environmental, social, or political stability? Protection of coastal areas? Reorganizing the ways in which we live our lives and generate and consume energy? Social transformation? Redistribution of wealth from industrialized nations to developing ones?

Different parties probably have each of these goals in mind and many more, but it's easy to sweep them all under the umbrella of emissions reductions. Consideration of geoengineering, I think, shines a light on those goals from a new direction, illuminating the landscape of policy preferences and values we bring to this issue. And that in itself may be very helpful; I think part of the reason we have such gridlock over climate policy is the fact that these agendas and values are often obscured rather than explicitly examined.

Similarly, the way we look at geoengineering itself is revealing and clarifying. Conventional wisdom in the field generally holds that SRM techniques, at least, should only be considered as a fallback option--a Plan B in case of emergency, presumably in the distant future.

But Mike McCracken has argued that, provocatively, that we ought to consider whether geoengineering should be used today, perhaps on a regional scale, to promote ecosystem health. Radical? Perhaps, but the logic is not obscure.

Last June, for instance, the U.S. Global Climate Change Research Program released a landmark report, Global Climate Change Impacts in the United States, which concluded that

"Climate-related changes have already been observed globally and in the United States... Human-induced climate change, in conjunction with other stresses, is exerting major influences on natural environments and biodiversity, and these influences are generally expected to grow with increased warming..." The report also noted that "Arctic sea ice ecosystems are already being adversely affected by the loss of summer sea ice."

The implications are clearly worth considering: If we are experiencing climate impacts now, at what point does it make sense to think about addressing them--and what techniques might be most effective?

Similarly, even if we agree that the risks of geoengineering justify keeping the option in reserve save for true "emergencies", the question remains: What would constitute a climate emergency, and when--and how--should we act to address it? We wouldn't want to wait until we've crossed a tipping point; it's a lot easier to keep things in balance than it is to restore the status quo ante after, say, the polar ice caps have already melted and the methane trapped in the permafrost has been released. But our understanding of potential tipping points and feedback loops within the climate system is so limited, we are not well-prepared to make good decisions about these questions yet.

What this suggests is that the scientific challenge ahead on climate is, in fact, far greater than the work that has been done to date. Geoengineering asks us to understanding the totality of the human influence on the climate and global ecosystems--and all the ways we can change it. As climate scientist Tim Lenton has remarked, "The climate is complicated. Why should we try to control it using just one knob?"

To many, the idea of controlling the climate at all may sound arrogant in the extreme. It's not; in fact, it's humility that directs our attention to the broad range of human influences on the climate and seeks to understand them.

Take, for example, one of the more minor examples of geoengineering--white roofs and roads--an idea that has been popularized here in California, more for its energy conservation benefits as for its effect on the earth's albedo, but Secretary Chu has elevated its profile in climate policy circles as well.

On one level, this is a relatively trivial idea. Given how slowly roofs are built or rebuilt, and how modest the effect is on the albedo and our total energy consumption, the technique is hardly worth considering; it clearly is not a solution to anything.

But I think it's very much worth discussing because it is a great example of what I'm talking about--it helps us realize that we need to look at the totality of the global energy-ecosystem balance, and recognize that there is more to promoting healthy global ecosystems than just cutting greenhouse gas emissions--which is a good thing, given our poor track record on mitigation.

It also exemplifies what I call "soft" geoengineering, which has very different characteristics from more aggressive global climate engineering schemes such as SO2-based SRM.

Another good example of underappreciated influences on the climate brought to light by geoengineering is the cooling effect that sulfate aerosols in the troposphere have had--and the ironic warming effects of reducing this conventional air pollutant. Understanding the full range of human influences on the climate, obviously, can shed important light on our actions and our opportunities.

Critics accuse proponents of geoengineering research such as myself of seeking a "quick fix" for the climate problem. I think nothing could be further from the truth. Geoengineering is not a solution, and climate is not a problem that can be solved, at least not within our lifetimes.

Climate change is a condition to be managed, and geoengineering potentially offers the prospect of a group of new tools to help manage it, adding to a sparse and so-far ineffective policy toolbox.

That's the key intellectual significance of this idea: Geoengineering, in all its forms, challenges us to start taking the climate seriously enough to seek to understand all of its component parts, how they interact with each other, and how we can influence them. This is much more science-based approach to climate, rather than a purely regulatory pathway, and I think it's more likely to produce the right results in the end.


Samuel Thernstrom is resident fellow at AEI and Codirector of the AEI Geoengineering Project.

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About the Author


  • Samuel Thernstrom has studied and written about environmental issues for twenty years, with a particular emphasis on global climate change. He served on the White House Council on Environmental Quality prior to joining AEI in 2003. As codirector of the AEI Geoengineering Project, Mr. Thernstrom studied the policy implications of geoengineering, or climate engineering. This groundbreaking field of climate science involves changing features of the earth's environment to offset the warming effect of greenhouse gases. He has been published on and in the Los Angeles Times and the Washington Post, and he has appeared on BBC News, ABC News, CNN, FOX News, NPR, and The NewsHour with Jim Lehrer on PBS.

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