Profile of David Keith

NEWSFOCUS

Sun blocker. Serious geoengineering research is long past due, says physicist David Keith.

ing infl uential academic papers, the Canadian scientist has become geoengineering’s public face, delivering sold-out lectures and vivid quotes to the media. He’s also become some- thing of a power broker, advising one of the world’s richest men on climate issues and doling out some $6 million of Bill Gates’s money to convene meetings and spur new research. And 2 years ago, Keith gained a high-profi le perch for promoting his views, moving from the University of Calgary in Canada to Harvard University. Now, Keith wants to bring geoengi- neering out of the ivory tower and into the stratosphere. He and a partner at Harvard are proposing one of the world’s first geo- engineering fi eld experiments, using a high- altitude balloon to release sun-blocking vapors into the atmosphere. And this month, Keith is releasing a book, A Case for Climate Engineering, in which he argues that “the

potential upsides of geoengineering” demand on October 28, 2013 greater research. Such studies “may show that these technologies will not work,” he writes. “Yet the sooner we fi nd this out the better.” It’s an audacious agenda for a scientist col- leagues describe as equal parts thoughtful, CLIMATE CHANGE unorthodox, and headstrong. And he faces a myriad of obstacles, including a lack of orga- nized government support and fi erce opposi- Dr. Cool tion from critics—one of whom calls Keith’s www.sciencemag.org sun-blocking ideas “barking mad.” He’s even gotten death threats. David Keith has helped usher geoengineering into the mainstream. Actually testing Further complicating matters is Keith’s a way to cool the planet is his next big challenge ownership stake in a company that is pursuing a different fl avor of geoengineering—sucking David Keith was a 26-year-old graduate stu- Few others, however, paid much attention. carbon dioxide out of the air. That has raised

dent in experimental physics when he first And for the next 15 years, discussions of geo- questions about fi nancial confl icts. And some Downloaded from heard of geoengineering, the concept of inten- engineering drifted between the fringe of aca- wonder whether Keith has the diplomatic tionally tinkering with Earth’s climate system demic research and science fi ction. Still, as savvy to win over opponents. “David does in order to counteract global warming. It was Keith built a career as a specialist on energy not suffer fools gladly,” says David Layzell, 1989, and some of his colleagues at the Mas- and climate issues, he periodically published Keith’s former boss at the University of Cal- sachusetts Institute of Technology (MIT) in papers suggesting that scientists needed to gary. “Everybody respects him—or is a little Cambridge considered the idea distasteful, take geoengineering seriously. terrifi ed of him.” Keith recalls. Discussing possible experi- In the past 5 years, they have. As carbon ments was “a de facto taboo” in the fi eld. dioxide continues to build up in the atmo- A polymath That didn’t deter Keith, who saw the dearth sphere, the U.S. National Academies, the Keith grew up in Ottawa, where his father of interest as a professional opportunity. Three United Kingdom’s Royal Society, and the and stepmother, both wildlife biologists, years later, he published his fi rst paper on the American Geophysical Union have all issued taught him how to stuff birds, enjoy the out- topic. Geoengineering needed a “systematic calls to explore expanding research into tech- doors, and work with his hands. After earn- research program,” Keith and a co-author con- nological fi xes. The number of scientists pub- ing a physics degree at the University of cluded after analyzing the few existing stud- lishing on geoengineering is growing, as are Toronto, Keith headed to MIT, where “he ies of possible approaches, including sucking citations of their work by infl uential groups, was an incredible hot shot,” recalls Harvard’s carbon dioxide out of the atmosphere with such as the Intergovernmental Panel on Cli- William Clark, an early mentor. machines and releasing particles into the sky mate Change (IPCC). But Keith was troubled by the military to block sunlight. Such exotic technologies, Keith has ridden geoengineering’s shift applications of his physics research and they argued, had the “potential to mitigate cat- from the fringe toward the mainstream—and instead drifted toward the burgeoning fi eld of

CREDIT: ELIZA GRINNELL/HARVARD SEAS ELIZA GRINNELL/HARVARD CREDIT: astrophic climate change.” has helped catalyze it. In addition to publish- climate and energy research. After he earned

www.sciencemag.org SCIENCE VOL 342 18 OCTOBER 2013 307 Published by AAAS NEWSFOCUS

Aiming high. A proposed experiment would use a balloon to release sulfuric acid vapor (A) and then measure its effect on ozone chemistry in successive passes (B).

his doctorate in 1991, his eclectic interests Keith’s persuasiveness came with a con- holds appointments in the schools of engi- led to an array of jobs over the next decade: fidence that could be alienating, however. neering and government, has brought him policy analysis at Carnegie Mellon University “David is usually right, and he has a high close to science and policy heavyweights— in Pittsburgh, Pennsylvania; climate model- degree of confi dence that he’s right,” says geo- and students who go on to become power- ing at the National Center for Atmospheric chemist Ken Caldeira of the Carnegie Institu- ful policymakers around the world. It’s also Research in Boulder, Colorado; building tion for Science in Palo Alto, California. And an opportunity to team with some of the atmospheric instruments at Harvard; and even that can be “off-putting to some people,” says nation’s top atmospheric scientists, and ramp a stint in environmental ethics at the Univer- Jane Long, an energy scientist at the Univer- up efforts on one of Keith’s priorities, devel- sity of Montana in Missoula. “A lot of rock sity of California, Berkeley, who nonetheless oping rules for governing geoengineering climbing, too,” Keith says. commends Keith’s “strong ability to get peo- research. And Cambridge offers a bully pul- Along the way, he published a num- ple to see his point of view, while seeing mul- pit for injecting the topic into international ber of provocative papers, including a 2001 tiple confl icting points of view.” discussions. Or, as Keith put it in a 2007 TED Science publication that questioned the In Calgary, Keith’s willingness to speak talk: “We need a broader debate … not just a potential of wind power to replace fossil his mind sometimes complicated his rela- few oddballs like me.” fuels, and analyses of hydrogen fuel, natural tionships with industry. A few fi rms refused gas, and the then-controversial concept of to partner with the university after Keith chal- A low-dose supplement carbon capture and storage (CCS): capturing lenged Alberta’s efforts to mine its oil sands, Keith hopes to jump-start that debate with A carbon dioxide from industrial smokestacks for instance. But Keith was becoming an Case for Climate Engineering. In 112 pages and pumping it underground. entrepreneur himself, launching Carbon Engi- of authoritative prose, he largely eschews fi g- Geoengineering continued to fascinate neering, a startup aiming to build machines to ures and technical terms in a bid to reach a him, Keith says, because it provided a new remove carbon dioxide from the atmosphere, lay audience. He begins by casting the cli- look at humanity’s relationship with nature, in 2009. One of its investors is Microsoft co- mate challenge in stark terms: Past emissions which he valued personally as an outdoors- founder Bill Gates, for whom Keith has served have already committed Earth to substantial man. Geoengineering “encourages us to as an informal energy adviser since 2006. warming, he warns; even aggressive emis- rethink some of our root assumptions about The amount of Gates’s investment in the sions cuts—if they ever materialize—can the means and ends of climate policy,” he company is undisclosed, but the mogul has only partly reduce climate risks. But geo- writes in his book. also provided roughly $6 million to the infor- engineering techniques could relatively By 2004, when the University of Calgary mal Fund for Innovative Climate and Energy quickly “cut the average rate of global warm- recruited Keith from Carnegie Mellon, he was Research, managed by Keith and Caldeira. ing in half for the next half-century,” he argues. considered a go-to voice on geoengineering, Since 2007, the fund has supported more In particular, Keith focuses on one tech- and he began building bridges with business. than a dozen research projects, most on geo- nique: releasing sulfuric acid vapor high in In 2007, he joined with four top executives in engineering. It also helps fund a weeklong the stratosphere, where it would scatter sun- Alberta’s powerful energy industry to write summer school on the topic, now in its fi fth light away from Earth’s surface. The approach a report touting the potential of CCS to curb year, which brings together physical and mimics the global cooling effect of large vol- carbon emissions. It drew darts from envi- social scientists. The networking opportunity canic eruptions, which spew sulfates into the ronmentalists, but led to a pledge to invest “shows David’s great value” as a scientist and stratosphere. But Keith envisions a “slow SCIENCE $3 billion in CCS technology by the Alberta organizer, says Benjamin Kravitz, a climate ramp scenario,” gradually adding sulfur over and Canadian governments, which had re- modeler at Pacifi c Northwest National Labo- decades to counteract about one-half the quested the study. “I’ve had a deputy minister ratory in Richland, Washington, whose work yearly climate change caused by humans. stop me and say it was amazing what David is supported by the fund. That would allow “ample time” to alter or

did on that report,” Layzell says. Keith’s 2011 move to Harvard, where he halt the procedure if there are surprises, he G. GRULLON/ CREDIT:

308 18 OCTOBER 2013 VOL 342 SCIENCE www.sciencemag.org Published by AAAS NEWSFOCUS notes. And the method could be relatively to use a balloon release less than a kilogram of A public perch cheap: A 2010 study he arranged suggested sulfuric acid vapor about 20 kilometers above A publicly funded experiment subject to cus- that the cost of starting the plan with aircraft Earth’s surface during the fall or spring, when tomary environmental review could avoid would be, incredibly, a few hundred million the stratosphere is very still. Chemical sensors such pitfalls, Keith says. But he faces obsta- dollars—“the price of a Hollywood block- aboard the balloon would then measure pos- cles of his own. One is his stake as president buster,” Keith writes. sible effects on stratospheric ozone. The craft of Carbon Engineering, which some observ- Keith highlights the risks. The particles would also repeat the experiment with water ers say poses a potential confl ict of interest could catalyze chemical destruction of the vapor, fi ngered recently by Anderson as a pos- because his call for greater investment in protective ozone layer, or—at high doses— sibly underestimated threat to ozone. geoengineering research could ultimately rob the climate system of crucial energy benefi t his own company. Such concerns, in required to drive precipitation. And even A hazy outlook fact, blocked Keith from serving on a cur- discussing the idea might undermine efforts Gates, among other tycoons, could fund rent National Research Council panel on to transition away from fossil fuels, he con- such an experiment. But Keith is adamant geoengineering. “With David straddling this cedes, or even prompt international tensions. that governments should lead on solar geo- academic-business divide, his company is But some modeling studies, he writes, sug- engineering research. International oversight going to hold him back,” Caldeira predicts. gest sun-blocking methods could reduce the agreements and government funding can “It’s impacting his academic career.” harm caused by warming, including heat make “the development of solar geoengineer- Keith sees “a sharp distinction in the role stress on crops “in the hottest and poorest ing technologies … as public and transparent of private enterprise” in the two fl avors of parts of the world.” as possible,” he writes. Government leader- geoengineering. Because sun-blocking tech- Still, many are skeptical. Last month, ship could also prevent potential confl icts of nologies hold global risks as well as benefi ts, the IPCC warned that solar geoengineer- interest, he argues, by preventing companies they are no place for private enterprise, he ing could “modify the global water cycle,” from winning monopolies on new technolo- says. His work in that area involves “open although it didn’t specify how much sulfur it gies and keeping them in the public domain. publications and no patenting.” In contrast, might take to cause concern. Other critics are Keith and Anderson say they will ask the U.S. he argues that fi rms serve a crucial function more direct: Efforts to manipulate climate government to fund their experiment. in developing air capture methods, which he with light-scattering particles are “barking So far, however, U.S. agencies have held says pose “local risks” akin to other industry. mad,” says climate modeler Raymond Pierre- back from funding geoengineering research, Such nuances are often lost in public humbert of the University of Chicago in Illi- and prospects overseas are dim as well. In debate. After one article criticized his pro- nois. One problem, he says, is sun-blocking 2010, the 197 nations that are members of the posed experiment, Harvard alumni were may do little to reduce overall peak global Convention on Biological Diversity adopted “writing to the [university] president … ask- ing why these maniacs are on your faculty,” Anderson says. And then there are the two death threats, apparently from people who believe Keith is part of a government conspir- acy. One caller last year was “verbally abu- sive and drunk,” says Keith’s assistant Hollie Roberts, prompting a report to the police. Colleagues, however, appreciate Keith’s increasingly public role as advocate. “It’s important to have good spokespeople on geoengineering, and Keith is an independent and hyperarticulate one,” says Caldeira, of Carnegie. “He’s a very deep thinker,” Long says. “You may not always agree with him, but you have to hear him out.” For his part, Keith says he’s learned from his time in the limelight and is taking greater care in what he says and writes. “It gets under my skin when I am made out to temperature increases under many scenarios. a resolution that asks governments to oppose be the rank advocate” for geoengineering, And it could even lead to a relatively sudden “geo-engineering activities that may affect he says. “It hurts.” So now he’s “trying to be global temperature spike, he warns, if the biodiversity.” And one U.K.-funded effort, the more disciplined about weaving caveats in,” effort is interrupted by a war or calamity. Stratospheric Particle Injection for Climate so that others can’t take his words out of To clarify and quantify such risks, Keith Engineering project, had to cancel a 2011 context. And his book tempers boldness with says researchers need to move beyond theo- fi eld experiment after it became mired in con- humility. “I myself have concluded that it retical debate to actual fi eld experiments. First troversy. Critics complained that research- makes sense to move with deliberate haste up, he argues, should be “process studies” that ers hadn’t adequately vetted the test, which towards deployment of geoengineering,” would be too small to have any appreciable involved spreading a small quantity of water Keith writes. “You may well reach a different impact on climate—studies like the one he vapor from a tethered balloon, or worked out conclusion. My goal is simply to convince and chemist James Anderson of Harvard have how ownership of any new technology might you that it’s a hard choice.” now proposed (see graphic, p. 308). The idea is be handled. –ELI KINTISCH

www.sciencemag.org SCIENCE VOL 342 18 OCTOBER 2013 309 Published by AAAS