Cutting Loose the Climate Future from the Carbon Past

Geoengineering demands a new way of looking at the world—one that can be troubling.

There will come a point, somewhere above Arizona, where—in the words of John Gillespie Magee Jr.’s much-quoted poem “High Flight”—you slip the surly bonds of Earth. Rising “where never lark, nor even eagle, flew with silent lifting mind,” you transcend the world below to tread the “untrespassed sanctity of space.” Higher than the sky is blue, decoupled from the Earth curved out below, you can appreciate everything within which you live with a new outsider wonder.

A Tucson-based startup called World View Enterprises is offering to sell its customers this cut-adrift communion for about $75,000 a flight when, a few years from now, its services are up and running. Like its rivals in the tourism of the untrespassed, Jeff Bezos’s Blue Origin and Richard Branson’s Virgin Galactic, World View reckons that there is a tidy profit to be made taking people who yearn for the sublime.

The difference between World View and its better-known rivals is that it does not plan to launch its passengers into the great beyond with rockets, but rather to loft them under vast balloons. Less drama, more duration—a stratospheric sojourn that lasts for hours rather than a pistoning, parabolic rise and fall. The ability to linger has attractions for other applications, too. If you want to put a communications package over a particular site without the expense of a satellite, World View will in time be happy to offer you a “stratollite” that does the job. And if you want to do something to the stratosphere’s thin air and see what effect your intervention has, the company can provide a platform for that, too.

It is that last possibility that brought Frank Keutsch and David Keith, two Harvard professors, to the Tucson firm. In 2018 they plan to use a package slung beneath a WorldView balloon to create a trail of tiny particles in the stratosphere and then investigate the particles’ physical effects. They call the effort SCoPEx, the Stratospheric Controlled Perturbation Experiment. In time they hope to investigate the effects such particles have on the chemistry of the stratosphere, too, particularly the finely balanced reactions continually producing and destroying its precious ozone.

SCoPEx will be the first experimental venture of Harvard’s new Solar Geoengineering Research Program, which is devoted to looking at ways to slightly reduce the amount of sunlight that reaches the surface of the Earth. Common sense suggests that this would lessen the effects of global warming; climate models confirm that. Placing into the stratosphere reflective particles of the sort that SCoPEx will investigate—at a rate of a million metric tons a year or so rather than SCoPEx’s few kilograms—is the most obvious way this might be carried out.

Keith, whom I came to know while writing a book about geoengineering and whom I now count as a friend, has been the driving force behind this new project and is the Harvard program’s first director. He believes that if geoengineering of this sort were to prove safe, and were to be appropriately governed, it could do a great deal to reduce the damage being done by the greenhouse gases that humans have pumped into the atmosphere. His program has attracted millions of dollars in funding from Bill Gates, among others. It represents the most ambitious research program into the practical possibilities of geoengineering to date.

Setting aside its balloon-based logistics, the dramatic and divisive global possibilities of geoengineering might seem to have little in common with the individualized, near-space, epiphany-tourism World View plans to sell. I think they share quite a lot. A big part of what will draw people to see the planetary curve of the Earth against the blackness of space is the expectation that the sublime beauty of the sight will deepen and even transform their feelings about the planet—that they will undergo a personalized recapitulation of the deep effect that the Apollo program’s pictures of the Earth had on the burgeoning environmental consciousness of the 1970s. Geoengineering offers, and perhaps demands, a similarly changed perspective. And it is one that can be troubling.

The new way of looking at the Earth that the Apollo images provided was double-edged. As anthropologist Tim Ingold wrote in his influential essay, “Globes and Spheres: The Topology of Environmentalism,” seeing the Earth from outside did not just expand people’s notion of the environment—it undercut it. Environments are things you find yourself inside; seeing one from outside abolishes that situating self-discovery, opening new estrangements instead. In Ingold’s words, “The notion of a global environment, far from marking humanity’s reintegration into the world, signals the culmination of a process of separation.” When the Earth itself, rather than its human and nonhuman inhabitants and our individual relationships to them, became the object of concern, the nature of environmentalism changed. It moved away from practice and the lived experience of joys and constraint and toward the realm of pure ideas.

I don’t for a moment doubt that the world needs ways of understanding the Earth objectively and as a whole—or that those ways of understanding have revealed profound risks to the health and happiness of many millions of humans, not to mention other species. But I still find Ingold’s analysis insightful. I worry that an environmentalism that focuses on “saving the planet” runs a pernicious risk of pitting those abstract needs against the interests of people whose voices are not heard enough—specifically, the global poor, desperately in need of modern energy services and commercial opportunities to lessen their misery. I also fear that framing environmental issues in terms of nothing less than the fate of the planet has an alienating, disempowering effect. Anticipating the spectacle of disaster on a geological, even astronomical, scale can offer a perversely liberating—even feckless—powerlessness; what could my or anyone’s action accomplish in the face of such sublime immensities?

These worries about the planet’s post-Apollo objectification are not, I have found, very widely shared. Most environmentalists seem to think “planet in peril” rhetoric is a matter of imagery and inspiration and that’s all. No such insouciance greets mention of geoengineering—almost everyone who talks about it, whether pro or con, thinks it matters a great deal. And that seems strange. For what is geoengineering but an operationalization of that Apollo worldview, one that takes the small step from seeing the Earth as a thing in itself to treating it as a thing to be manipulated, from objectification to instrumentalization? In the iconography of geoengineering—the images seen on posters for meetings or placards protesting them, as well as in illustrations for articles and the like—those Apollo images of the Earth turn up again and again. But they are routinely reinterpreted as a nut with a wrench turning it, or as a thermostat dial being adjusted by a vast and disembodied hand.

The god’s-eye view is a necessary precursor to the godlike power. But that does not mean the power does not matter in itself. Geoengineering may grow out of a view of the world that in other circumstances seems to most people unproblematically inspiring. But it would be silly to deny that it brings new problems with it. Who would wield its power, and in whose interests? And what would it do to people’s personal motivations for environmental action? Most environmentalists seek or enjoy a particular sense of what it is to care about nature and protect it. If environmental action is something that comes from outside, uncoupled from any change in the way we lead our lives, does
it still deliver what the environmentalist spirit craves?

Similar questions are familiar from other conflicts within environmentalism. “Ecomodernists” such as Stewart Brand, Ted Nordhaus, or Erle Ellis argue for saving the environment through an intensification of human activity: more intensive—meaning genetically modified—farming, more intensive—meaning nuclear—energy sources, more intensive—meaning urban—lifestyles. The human footprint becomes deeper but smaller; space is saved for the wild.

It was through such thinking that the term “decoupling” entered the environmental vocabulary. Previously largely a term of art in physics, it was imported by Jesse Ausubel to express what has become the core of ecomodernist belief: that continuing economic growth no longer requires increased environmental impact, and that this decoupling can be encouraged until it becomes more or less complete.

These ideas sound reasonable—indeed, inspiring—to their proponents. They provoke strident resistance elsewhere. Some simply refuse, on the basis of history, human nature, or both, to believe that humans enjoying ever greater and more concentrated technological power will use it as wisely and immaterially as the ecomodernists want; many see no hope for an environmentalism that does not seek fundamental limits on consumption and economic growth.

There is also a deeper feeling that ecomodernism misses the point; that if it were to succeed, it would be by decoupling not just the economy from the environment, but also people from the nature they need. Nuclear-powered, LED-lit, hydroponically nourished, carbon fiber–skeletoned, skyscraper farms might be wonderful things; but these are not the wonders, by and large, that people join the Sierra Club for.

Geoengineering makes seemingly similar promises in a concordant technocratic key—and provokes similar fears. It does not suggest merely that human activity can be decoupled from environmental harm. It suggests that the future can be cut loose from the past—that the legacy of warming stacked up in the atmosphere, molecule by molecule and gigaton by gigaton, might perhaps be set at naught. There is a grandeur in this, and a liberation—just as there is a grandeur, and a liberation, in looking out from the edge of space at the curved Earth set out below. But is there not, also, a deep irresponsibility in seeking to clean the slate? How much transcendence can a conscience bear?

Solar geoengineering feels essentially deracinated, top-down, technocratic, and—for all those reasons and more—dangerous. But at the same time, it offers something that most current environmentalism does not: a plausible path toward the reduction of near-term harm to people and the natural environment.

There is an odd irony here. It is true that solar geoengineering of the sort Keith is researching feels essentially deracinated, top-down, technocratic, and—for all those reasons and more—dangerous. But at the same time, it offers something that most current environmentalism, including that of the ecomodernists, does not: a plausible path toward the reduction of near-term harm to people and the natural environment.

At the UN’s 2015 Paris summit, the nations of the world committed themselves to keeping global warming “well below” 2 degrees Celsius and, ideally, as low as 1.5 degrees Celsius. This is by no means ideal. A two-degree rise will do a lot of damage and hurt a lot of people. It could render some currently semi-arid and excessively hot places uninhabitable; it will deeply disrupt Arctic ecosystems; it may well, in the long run, doom the Greenland ice cap. And though two degrees is what Paris aspires to, it is not what it looks likely to deliver. The specific cuts in greenhouse-gas emissions to which the nations signing the agreement actually committed themselves were not remotely ambitious enough for that.

The Trump administration’s petulant and nihilistic withdrawal from Paris probably damages its prospects further. That does not mean there is no hope. As renewable technologies grow cheaper and transport is increasingly electrified, the rate of progress on emissions reduction may increase faster than the current Paris pledges would suggest, whatever the US federal government does. But the degree to which progress needs to speed up if the Paris goals are to be met remains extraordinary. A determinedly optimistic scenario put forward by the Carbon Tracker Initiative, an NGO, suggests that if renewables continue to grow faster than generally expected (as they have been doing), there might be a fifty-fifty chance of no more than 2.4 degrees Celsius of warming. But even if policies became much more ambitious and people, within a few decades, started pulling carbon dioxide down out of the air and storing it away permanently, the risk of breaking the two-degrees barrier would still be more than 50 percent.

For a good chance of limiting global warming to 1.5 degrees Celsius, the world would need even more ambitious reductions in emissions and, in the second half of the century, a truly vast drawdown of carbon dioxide. There may be ways to do this in a clean, efficient way. But as yet they are unproven. Policy analysts currently tend to assume that a carbon drawdown will involve burning biomass to generate electricity and pumping into deep storage the carbon dioxide produced in the process. The biomass presumably would be grown on plantations or through vast ocean-farming systems. But most such discussion ignores the sheer size of the interventions required; to get into the right ballpark, you need plantations across an area bigger than India. If the creation of plantations on such a scale were politically feasible (I think it isn’t), the sacrifice of arable land or wilderness would be a terrible cost.

None of this is to say that the world cannot, over the coming century, drastically reduce its emissions or indeed start to reverse them. But the realistic chances of doing so in time to stave off real harm to the people who suffer most from climate change—poor people in hot countries—are very thin. Unless, that is, you add another form of action to the agenda. That is where solar geoengineering comes in.

To imagine that humans can simply stop being a planet-changing force is unrealistic. Thinking that we might find a way to act responsibly may be just as daft. But it seems to me a better foolishness.

Note that it is indeed an addition, not a replacement. Neither Keith nor, as far as I know, any of the other researchers looking at the feasibility, side effects, and safety of solar geoengineering sees it as a possible alternative to reducing greenhouse gas emissions. For long-term climate stability, fossil-fuel greenhouse gas emissions have to be brought down to zero; they need to come down to zero to put an end to ocean acidification, too. What geoengineering might do is slow and/or limit the warming which will take place in the time it takes for that global zero to be reached. A layer of fine particles in the stratosphere, capable of reflecting away enough sunshine to cool the planet by just 1 degree Celsius, could be the difference between meeting the most ambitious goal envisaged in Paris and crashing through its upper limit.

That immediately poses the question of what else such a layer of fine particles might do. One possibility is that it might damage the ozone layer. Particles in the stratosphere tend to catalyze ozone-destroying reactions. It is the presence of clouds in the stratosphere around Antarctica that accounts for the ozone hole there; the sulphate particles produced after large volcanic eruptions reduce ozone levels as well as cool the planet (Such episodes of natural volcanic cooling are one of the reasons for thinking that solar geoengineering can have a cooling effect, though they are not a precise analogue). One of the main purposes of SCoPEx is to see whether it is possible to find potentially planet-cooling particles which damage the ozone layer less—or perhaps even replenish it.

Then there are the effects on the climate itself. The cooling triggered by particles in the stratosphere and the warming created by greenhouse gases are not perfect opposites. Greenhouse gases work day and night, summer and winter; they have different effects at different altitudes, warming the middle layers of the lower atmosphere and cooling the stratosphere itself. Stratospheric solar geoengineering works by day only thus it does little to, say, Arctic winters. It cools the surface more than the air above it, and it actually warms the stratosphere. These differences mean that the weather patterns in a world where some greenhouse-gas warming is countered by stratospheric aerosols would not be those of a world where that greenhouse warming never took place, even if the average temperatures were the same.

Experiments such as SCoPEx can tell you what solar geoengineering particles will do to the chemistry of the stratosphere. However, they can’t tell you what a veil of particles spread round the world would do to the climate—any more than spraying carbon dioxide into a little patch of the atmosphere would tell you the impacts of greenhouse gas warming. You can’t do experiments at the scale of the Earth without, well, doing experiments at the scale of the Earth. But you can use the models built to understand greenhouse gas warming to look at worlds in which geoengineering takes place, too—what I call “doubly altered climates.” Such modeling is imprecise, and probably far from reliable when looking at specific regions. But the same is true of models that tackle the effects of greenhouse gases alone—which is to say, the models on which the limits and aspirations of the Paris agreement are based.

Such studies strongly suggest that a couple of degrees of geoengineering would reduce climate impacts over much of the world. Weather patterns would still change: “doubly altered” is not completely canceled out. Altering stratospheric circulation would influence jet streams and hence surface weather. Rainfall patterns would change, though that would not necessarily mean more droughts and might mean fewer floods.

If you had a utilitarian choice between a world with 3 degrees Celsius of greenhouse warming or a world with the same amount of greenhouse gases but enough solar geoengineering to limit the increase in temperature to 1.5 degrees Celsius, and you had only modeled climate impacts to go on, it would be pretty much a no-brainer. The 1.5-degree world would be better for almost everywhere—lower average and peak temperatures and thus less heat stress for humans and ecosystems, lower sea levels, less ice loss, fewer extreme events.

The problem is that climate impacts in a particular scenario are not the only thing at play. People and politics matter, too. Model studies strongly suggest that, for any significant level of geoengineering, some regions would benefit from adding further particles to the stratosphere while some others would not. Such tensions could drive the world toward more geoengineering than is optimal, or toward large-scale international conflict, or both.

There is also an obvious risk that geoengineering might prove a victim of its own success. If it looks like it is actually
doing the good it seems to promise—or even if it just looks plausible that it might—then incentives to keep on with the vital work of reducing greenhouse-gas emissions will start to weaken. The world might let itself go.

If today’s energy optimists are correct, that may not matter too much. If green-energy progress really is now unstoppable, and if technologies for pulling carbon out of the atmosphere on a large scale really are going to become available, then emitting a bit more carbon dioxide in the meantime might not be the worst thing. But those are big ifs—especially if the relaxation follows from the promise that solar geoengineering looks plausible, rather than from a demonstration that it actually helps.

Worries such as these are real, serious, and widespread. They lead some wise and cautious people to think that solar geo-engineering is best left off the table. They judge that the potential political harm outweighs any promise. And because it is easier not to discuss something than to discuss it—this inertia-through-omerta has won out.

No policy wonk, activist, or politician pays a price for not discussing solar geoengineering when talking about how the planet might meet the Paris goals. No one makes a career in geoengineering research: Keith is the only high-profile scientist currently devoting almost all of his research efforts to it. Just one researcher whose doctorate dealt with geoengineering has so far gone on to a tenured university position. A study of geoengineering carried out by the Royal Society in 2009 suggested that perhaps as much as one-tenth of climate research should be devoted to examining such ideas. The actual figure is closer to one one-thousandth, and the rate of publication on the subject is dropping.

Which is why I think SCoPEx matters. A real experiment, up in the stratosphere, will focus attention. That may be uncomfortable for Keith and his colleagues; many will see their high flights not as a quest to touch the face of God but as an attempt to besmirch it. The public engagement programs Keith would like to set up around it may reveal deep and unshifting antipathies. It’s a fair bet there will be lawsuits and demonstrations, both by environmentalists concerned that it crosses a stratospheric Rubicon and by “chem-trailers” who believe that the upper atmosphere is already being deliberately manipulated as part of a vast government conspiracy. Good faith will be questioned; tempers will flare; the online threats made against Keith and others who express views on the subject will increase.

Through all this, though, the wider debate may get the real airing it still needs. No one denies that geoengineering presents risks. The questions that matter are how they stack up against the risks of not geoengineering and how they can be managed. That second question is the purview of the other big, recent development in this small, important field: the creation of the Carnegie Climate Geoengineering Governance Initiative led by János Pásztor, a diplomat who previously worked as a climate adviser to Ban Ki-moon. Pásztor and the team he is putting together hope to provide frameworks in which the political, legal, and ethical issues geoengineering raises might be addressed. Their work should help clarify what matters when considering SCoPEx and subsequent research, and to whom it matters. It should also help ensure that the voices of the poor, who are at greatest risk from climate change, are in fact heard.

It may be that geoengineering really does raise more risks through politics than it reduces by scattering sunshine. And perhaps the consensus on this will be so strong that no nation will choose to run those risks and geoengineer anyway. The world would then be left with emissions reductions, adaptation efforts, and the harm that follows when those are insufficient—as they all but surely will be. It seems to me, though, that it is worth trying hard to find out whether a form of geoengineering that is safe, just, and governable might also be politically feasible, rather than assume that it isn’t.

This is not just because there is a moral duty to try to reduce the harm climate change is doing. It is also because those images of the Earth from space, that view of “nature” made possible only by the highest of technologies, resonate with a genuine and irrevocable change in the human relationship to the planet.

As Ingold’s writing and many worries about geoengineering attest, this change is far from an unmixed blessing. Nor is it an adamantine curse. As those yearning for the view from the windows of a pressurized microhabitat slung below a World View balloon may yet learn, it is both a new breach and a new connection. It is problematic; it has potential.

Humans, spread across the planet’s face, tied by trade across its oceans, lifted up into its skies, are now the Earth’s environment, as the Earth is ours. We shape each other. In our mutual embrace, we both deserve respect and care. But only one of us is capable of expressing that duty and acting on it. If the world can’t bring itself to talk about such care—even if it is to conclude that its wise exercise is beyond human judgment or perhaps human technology—then it is failing both itself and the rest of the planet.

To imagine that humans can simply stop being a planet-changing force is unrealistic. Thinking that we might find a way to act responsibly may be just as daft. But it seems to me a better foolishness.

[Oliver Morton](https://en.wikipedia.org/wiki/Oliver_Morton_(science_writer) is a senior editor at The Economist. Prior to that, he was Chief News and Features Editor at Nature. His writing has appeared in the New Yorker, National Geographic, Discover, Time, New Scientist, The New York Times, The Financial Times, and many other outlets. His most recent book The Planet Remade was shortlisted for the Royal Society Insight Investment Science Book Prize.