Future Tense

Can Space Reflectors Save Us?

Why we shouldn’t buy into geoengineering fantasies.

This piece arises from Future Tense, a collaboration among Arizona State University, the New America Foundation, and Slate. A Future Tense conference on geoengineering will be held at the New America Foundation on Monday, Sept. 27. (For more information, please visit the  NAF Web site.) Read more of  Slate’s special issue on geoengineering.

When, in late 1965, the problem of climate change first arrived on the desk of the president of the United States, Lyndon Johnson’s advisers presented him with only one possible solution:  geoengineering. They suggested that scattering small reflective particles over millions of square miles of ocean might reflect enough sunlight away from Earth to moderate the warming. 

After lying dormant for more than a generation, geoengineering is back with a vengeance. A rush of new books and official reports urges us to think seriously about addressing climate change by painting roofs white, injecting reflective aerosols into the atmosphere, or even by launching space shields that would protect us from solar radiation. This newfound interest in geoengineering is partly a reaction to the steady increase in greenhouse gas emissions, which has continued despite scientific consensus, international treaties, and solemn declarations. In the background is the fact that many of us find Promethean solutions almost irresistibly attractive.

Even some proponents of these technologies, such as prominent Canadian climate scientist David Keith, fear that geoengineering research will distract us from the basic challenge of reducing carbon emissions. But I doubt that we could be any more distracted—only the global recession has been able to significantly reduce overall emissions.  My fear is that geoengineering will drive out funding for adaptation, especially for the poorest populations, who have done the least to cause climate change and to whom it poses the greatest dangers.

Geoengineering is often discussed as a “backstop” that can prevent climate change from overwhelming us if we fail to stabilize concentrations of greenhouse gases. (See for example the National Academy of Sciences’ recent summit, “America’s Climate Choices”.)  Like the Colt 45 “peacemaker” of the old West, geoengineering would be the technology of last resort. It stays in the holster until and unless it’s needed—but it needs to be in the holster, proponents say.

The reality is that there’s no Colt 45 for geoengineering. Even in the most optimistic scenario, geoengineering would solve only some problems caused by our emissions while neglecting or exacerbating others. Managing solar radiation might reduce mean surface temperature, but little is known about regional effects on weather. Moreover, this approach would do nothing to address ocean acidification or a host of other problems. Removing atmospheric carbon dioxide, another geoengineering proposal, could have unpredictable climate effects and disastrous consequences for local ecosystems.

After years of research, the basic structure of the climate change problem is clear. The lifestyle of the global middle class is committing people for the next thousand years to a chaotic world significantly different from the one in which most human cultures developed and flourished. Even if we were to eliminate our emissions overnight, excess carbon would remain in the atmosphere for centuries, affecting climate and altering Earth systems. For those who can afford dikes, health care, food, and the possibility of migration, climate change will merely raise the price of the good life, if they are lucky.  For those who cannot afford these goods, the consequences will be devastating. 

Increasingly, proponents are marketing geoengineering as a technology that will benefit these poor people, who will suffer most from climate change. Rather than spending trillions to curb our emissions, adapt, or compensate victims, we’ll give our own scientists billions to prevent the bad consequences from ever occurring. Listen up, developing world: The people who brought you climate change are here to save you from it.

But just as there’s no Colt 45, there’s no John Wayne in geoengineering’s Hollywood story, either. There’s no agent who has the moral and legal authority to pull the trigger, much less the wisdom to know when it ought to be done. Not the U. S. government nor some scientific or philanthropic elite. Intentionally changing climate is a way of exerting power on a global scale in a context in which relevant norms, conventions, and treaties barely exist, are highly ineffectual, or very controversial. Yet the people of the world will have their say about it, one way or another.

While the lack of a John Wayne figure is difficult to rectify, many scientists advocate launching a dedicated research program to produce the geoengineering equivalent of the Colt 45. The program would start small but could gear up to the scale of the Manhattan Project, advocates like climate scientist Philip Rasch suggest. Proponents of this strategy say that they are calling for research rather than deployment, and much of the literature assumes there is a bright line between the two.

Bright lines, however, have a way of fading, particularly when it comes to dedicated research programs. In 1983, President Reagan created the Strategic Defense Initiative, a program devoted to developing technologies that would protect the American homeland from nuclear attack. Despite large costs and widespread opposition from many of the nation’s leading scientists, Reagan’s initiative has survived for more than a quarter-century, focusing on different technologies and wrapping itself in different purposes. It has led the United States to withdraw from the Anti-Ballistic Missile Treaty in 2002, increased international tensions on numerous occasions, and siphoned money away from valuable uses toward technological fantasies. Large research initiatives can be tougher to kill than vampires: They feed fortunes, careers, and reputations. As with the Strategic Defense Initiative, a dedicated geoengineering research program risks creating a self-amplifying cycle of interest groups and lobbies, building momentum toward eventual deployment as a way of justifying the research.

Geoengineering is fraught with risk, but some technologies may have a place in our portfolio of responses. They will have to compete against renewable energy projects, conservation, adaptation programs, and other alternatives on the grounds of cost, feasibility, and moral and political acceptability. This amounts to abandoning the Promethean dream and entering the messy world of climate politics. We have created a problem of climate change and we must mobilize all of our resources in addressing it.  But John Wayne is dead, and there is no Colt 45 peacemaker in sight.

Correction, Sept. 23, 2010: Because of a copy-editing error, the article originally listed the incorrect first name for the author.

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