Hack the PlanetScience's Best Hope - or Worst Nightmare - for Averting Climate Catastrophe
John Wiley & SonsCopyright © 2010 John Wiley & Sons, Ltd
All right reserved.ISBN: 978-0-470-52426-8
Chapter One It's Come to This
David Battisti had arrived in Cambridge, Massachusetts, expecting a rout, a farce, a bloodbath. So had many of the other scientists who had joined him that frigid morning from around the country. It was an invitation-only workshop on climate science in November of 2007 for which they convened at the American Academy of Arts and Sciences, an airy temple to diligence and scholarship one block from Harvard University. Battisti shuffled out of the Massachusetts morning air and into the Academy's expansive premises.
The workshop's unholy topic was geoengineering: the concept of manually tinkering with Earth's thermostat to reverse global warming. Organizers had arranged the event to find out whether respected climate scientists such as Battisti might support research into the controversial idea. In a button-down shirt opened two buttons down, Battisti poured his coffee and watched the scientists fiddle with their muffins. One couldn't take planethacking seriously, he figured, because there's no way we'll ever know enough about the atmosphere to claim we can control it. Just because the radical notion had made it from the outer fringes of Earth science all the way to Cambridge didn't mean the group was going to legitimize it, he thought.
Since the 1960s, a handful of scientists had dreamed up various schemes to intentionally alter the atmosphere on a global scale: flying enormous sunshades above Earth, creating billions of thicker clouds at sea, or spewing light-blocking sulfate pollution at high altitude to mimic the cooling effects of volcanic eruptions. Ecologists imagined brightening the planet's dark surfaces to reflect more sunlight, by spreading white plastic across certain deserts. Marine biologists explored growing algae blooms to suck billions of tons of carbon dioxide from the sky.
Each concept took a smidgen or two of sense and added scientific optimism and a dollop of whimsy. Mostly back-of-the-envelope affairs, the papers that described them included just enough observations or calculations to suggest the ideas might work. The scientists who wrote them knew the concepts were raw and with few exceptions understood them to be options reserved for worst-case scenarios. To the broader community of climate scientists, proposing even to study deliberately altering the atmosphere was a heretical idea.
As Battisti poured himself coffee, he saw one of the heretics standing beside the buffet table. "That guy is scary," Battisti whispered to a colleague. It was Lowell Wood, a nuclear physicist with a broad, reddish beard and a dark jacket. His wide torso was bisected by a tie featuring the periodic table of elements. From his perch at a California nuclear weapons lab, Lawrence Livermore National Laboratory, Wood had won notoriety, if not ridicule, for proposing in 1997 to control the atmosphere's thermostat by scattering chemicals in the atmosphere. He had done so in collaboration with his aging mentor Edward Teller, the father of the hydrogen bomb. Teller, whose conservative views had often put him at odds with the left-leaning scientific establishment, had advocated in the same year that geoengineering was a better way to tackle the climate crisis than the Kyoto accords.
Wood was among a handful of geoengineering enthusiasts (for lack of a better term) who had organized previous gatherings in recent years on the topic. Organized in part by Harvard University, the 2007 meeting was to bring the geoengineering true believers together with top scientists who had long dismissed the idea as a dangerous-or, moreover, a ridiculous-fantasy. "I want to get the mainstream climate community together, the brightest stars," the meeting's co-organizer, Dan Schrag, had told me. Schrag was a geochemist at Harvard who managed to know everybody in the climate community despite a reputation as a bit of an agitator. It had taken someone like Schrag, naturally, to bring together scientists like Lowell Wood and David Battisti. "I wanted to broaden the discussion," he told the scientists as they sat down in a conference room with high ceilings.
From Harvard had come scientists in geochemistry and the atmosphere, as well as a distinguished physicist wearing a small cap. MIT contributed ocean and hurricane specialists. Battisti, from the University of Washington in Seattle, was an expert on atmospheric patterns and dynamics. He told me he felt skeptical of technological solutions to massive problems such as accumulating greenhouse gases. He'd grown up with a simpler understanding of the environment, he said, regularly visiting a family dairy farm. Battisti called himself a "progressive on most issues," and had joined seventeen colleagues in petitioning the U.S. Supreme Court in a case in which they argued that the Bush administration had "mischaracterized" scientific findings they had published. You don't have to convince me of the severity of the climate crisis, thought Battisti. He found a chair along a set of floor-to-ceiling windows looking out on an icy patio. But if the scientists in the room called for more studies of ideas such as Wood's, it would mean endorsing a research field that had always been considered closer to science fiction.
Or, suggested Dan Schrag in his introductory remarks at the meeting, if geoengineering was only to be explored in a worst-case scenario, the decision to conduct research on it would be tantamount to acknowledging that the worst-case scenario had come or was frighteningly close. Accordingly, the slides in Shrag's PowerPoint presentation were dread-inspiring. Fossil fuel emissions were growing by 3 percent a year, he said, and China and India were only getting started burning their share of the world's coal. The level of carbon dioxide in the atmosphere seemed headed for twice the pre-industrial level, he said, and it seemed plausible that it would reach that concentration by the end of the twenty-first century. "We're not only at the business-as-usual, but we are well above all of the business-as-usual scenarios." "Business as unusual," I thought. Earth's atmosphere had warmed 1.3°F since the 1950s and was certain to gain another degree this century as the oceans warmed. The world was rallying to set up rules to regulate carbon dioxide pollution, but few in the room were optimistic that regulations passed by the United States or the international community would be aggressive enough to stem the problem.
Schrag flipped to a slide showing Antarctica. "Are the polar ice sheets vulnerable?" the caption read. "If Greenland and/or West Antarctica started to slide into the ocean, could we engineer a way to stop it?" The seasonal ice that waxed and waned on the surface of the Arctic Ocean was disappearing at an alarming rate of 3 percent a decade. "The way the Arctic ice holds on is by the skin of its teeth," said a Harvard climate scientist. Everyone in the room had heard the body of evidence and knew how damning it was. But there was a unique intensity to hearing it all at once, in a small room, with a few dozen of the world's top scientists dispensing with the niceties. The sense of desperation hung in the air like smoke from a coal-burning power plant.
Then came the would-be saviors, played by scientists, blueprints in tow. A physicist described how to use navy guns to fire droplets of sulfate pollution into the upper atmosphere, where they would reflect a small percentage of the Sun's rays, providing a modest but dependable cooling effect. By launching billions of tiny disks into orbit around the Sun, said an expert on telescopes, engineers would be able to redirect a small amount of light from striking Earth, having a similar effect. ("I got a little money from the Discovery Channel to make some of this stuff," he explained.) Modeling research had suggested that the sulfate aerosols method could be performed for a fraction of the cost of transforming the world's energy system. That technique mimicked the cooling role that volcanic eruptions played in Earth's climate. By studying previous volcanic eruptions, scientists estimated that geoengineering the upper atmosphere with this particular technique could cool Earth by as much as 4°F in a few years.
Local climates, one scientist suggested, could be "adjusted to taste." Might the aerosols method, with years of study and improvement, be a "technical pathway to Mediterranean climates" for most anyone who wanted them, as one scientist suggested? Chris Field, a prominent ecologist from the Carnegie Institution of Washington blanched slightly. (Among other problems with that particular suggestion, he said, is that wheat and other major crops require a rainy season not found in Mediterranean climates.)
Radical notions like those were why so many scientists in the mainstream have avoided geoengineering for so long. "Right now a very small number of people have worked on this for a small percentage of their time, as enthusiasts," said physicist David Keith, whose early papers on the radical concepts gave him particular authority among the armchair geoengineers. Keith was a wildly bright guy with antiestablishment leanings. He'd turned down an academic job at Princeton University to start a special energy group at the University of Calgary. There he'd made his name as an innovative energy and climate scientist, attacking more than his share of sacred cows while blessing heresies. Wind power could disrupt the weather; burning wood made climate sense-if you captured the gases you produced; and hacking the planet, though not a concept to be taken lightly, deserved attention beyond the pages of Popular Mechanics. Since graduate school, Keith had struggled over the question of whether studying and publicizing the idea of geoengineering would undercut efforts to reduce emissions of carbon dioxide. "A few of us are nervous to talk about this publicly," he admitted to the group.
"The engineering that dare not speak its name," mused a Harvard physicist named Bob Frosch. Sixteen years earlier, he had battled with fellow members of a federally sponsored panel who opposed his effort to include a chapter analyzing geoengineering concepts in a major national report on climate. "It was the only time things got vituperative on one of these panels," said Frosch. (The little-noticed chapter was included.) By the same token, an atmospheric scientist had told the organizers before the Harvard meeting that it should not be sponsored by the school in case the setting could be construed "as an endorsement" of the wild idea.
"This is generation zero for climate modeling for geoengineering," Ken Caldeira of the Carnegie Institution of Washington told the group when it was his turn to talk. Since 2000, the geochemist had published studies in which relatively crude computer simulations suggested that cutting the amount of sunlight received by Earth by 2 percent might counteract the warming expected in the twenty-first century. In the intervening years, he had argued for others to pursue the research while leading a small band of true believers who for years had toiled on the edges of respected science conducting geoengineering research on paper, without federal sponsorship.
This was the Geoclique, as I called them, led informally by Caldeira and Keith. Some were topflight scientists, such as Caldeira; some were knowledgeable retirees or what seemed to be hobbyists. On an online discussion group they discussed the scientific merits of various techniques and vented about the political obstacles facing their controversial field. Caldeira's expertise was the ocean, though he had been a philosophy major in college, a programmer on Wall Street, and a researcher in the rainforest. While he had gained proficiency in atmospheric science, in part because of his interest in geoengineering, his value to the nascent geoengineering cause was as much a spokesman-organizer as it was a researcher. He and Keith managed a $1.5-million fund provided annually by Bill Gates to study geoengineering.
Keith likes to think of scientists studying geoengineering as members of either the Blue Team or the Red Team, depending on their temperament and role. Blue Team members, such as Lowell Wood, have personalities that incline them to invent ways to alter the atmosphere. Keith leans blue. Russian climate scientist Yuri Izrael and his team also are solid Blue-Teamers. Red Team members, such as a plucky climate modeler named Ray Pierrehumbert, were generally skeptical of geoengineering and strove to find flaws in the blue team's work. Caldeira was bluish-purple. During his presentation he explained why he believed the sulfate technique might protect the world's coasts from the rising seas: "By dialing the radiation where you want it you can get more or less ice," he said. "If you're trying to get snow to fall on top of Greenland, this may be what you want." Having dismissed the concept of geoengineering out of hand before the meeting began, Battisti wasn't a member of either team, though his inclination seemed Blue.
At lunch, Battisti challenged Caldeira's contention that the sulfate technique would reverse the melting of the polar ice caps. "I don't know that," said Battisti, citing the model's simplistic depiction of the ocean. The best atmospheric scientists in the world, including himself, he said, simply didn't know enough about Earth's atmosphere to be making claims about how a renovation effort would turn out.
It's difficult to weigh the risks and possible benefits of planet-hacking concepts when both were uncertain. "I don't actually work on geoengineering, and I don't especially want to work on geoengineering," said Pierrehumbert. "But now that the genie is out of the bottle, I feel I have to." He shared with the group an unpublished experiment using a computer model of the atmosphere. In it, he quadrupled the amount of carbon dioxide in the sky, but kept the planet cool with a yearly dose of aerosol geoengineering. He warned that once the experiment began, a halt in the geoengineering effort-"by, say, a war or revolution"-would result in a hellish 14°F temperature jump in the tropics over three decades, bringing with it, presumably, unimaginable ecological impacts. (One climate scientist later compared the global climate addiction to alcoholism, and geoengineering to dialysis that allows the patient to continue drinking. Disrupting the geoengineering, he said, would be like unplugging the dialysis machine. So blocking the Sun's rays might buy humanity a little time, but it made cutting carbon pollution even more important, not less.)
Could scientists hope to answer the question about whether geoengineering could help to reverse the catastrophic demise of Greenland's ice sheets, if scientists found that happening? "We don't know how to model the ice sheets," Pierrehumbert told the group. "We may not have time to understand the system well enough before we act," said a Canadian postdoc.
"In the next twenty years a president may decide that he or she wants to know whether geoengineering can help prevent Greenland from melting," Schrag told me. Facing dire straits in the future, policymakers would no doubt turn to climate scientists to ask whether radical means to take control of Earth's climate could work. "Will we have done research to have a good answer or not?" Some of the scientists in the room questioned whether their field would ever be able to provide a sufficiently certain answer to allow society to make a truly informed decision about planethacking. Which meant there was a decent chance it could be deployed without sufficient care. "I am really darn scared," Battisti told the group. "No one wants to see this happen. No one wants to deploy this stuff."
"If we communicate to the general public that geoengineering is a tool in our back pocket in case of an emergency, we're doing them a disservice," said a Canadian policy expert. "The public will then do less to lower their carbon emissions."
Keith seemed to resent the implication. "Being silent is unethical and arrogant," he said.
Pierrehumbert looked indignant and jumped in. "There's no denying that there's a risk that this will undercut burgeoning mitigation efforts." he said. "I would ask people not to accuse others of being unethical if they are acting so as not to let the cat out of the bag."