A panel of the National Research Council (NRC) is calling for federal funding of research into two controversial areas of climate science: removing carbon dioxide directly from the atmosphere and albedo modification (AM), or shading the planet from the sun by tinkering with the sky. The recommendations, found in a two-volume report released today, move the so-called geoengineering techniques, long verboten among scientists, one step closer to the mainstream.
“The two main options for responding to the risks of climate change involve mitigation—reducing and eventually eliminating human-caused emission of CO2 and other greenhouse gases—and adaptation,” the authors write. “It may be prudent to examine additional options, namely [carbon dioxide removal] and albedo modification.”
Strategies to remove carbon dioxide from the atmosphere and store it are becoming possible but are “limited by cost and technological immaturity,” concludes the 16-member panel, which was led by geoscientist Marcia McNutt, the former head of the U.S. Geological Survey and now editor-in-chief of Science (publisher of ScienceInsider). In contrast, “albedo-modification technologies, which aim to increase the ability of Earth or clouds to reflect incoming sunlight, pose considerable risks and should not be deployed at this time,” the panel says. But the federal government should fund studies into both, it adds.
That recommendation may help scientists who for years have failed to secure much federal funding for such work. “A clear call for research, including field experiments, might translate into government action,” says climate scientist David Keith of Harvard University. “It might be the ‘permission’ that [federal] program managers feel they need to move ahead.”
The volume on carbon dioxide removal, or CDR, techniques—which include machines that suck carbon from the air and schemes to burn or bury biomass—is “expensive” but does not introduce novel risks. That’s because removing carbon from the atmosphere addresses the root of the global warming problem, the accumulation of greenhouse gases. Modeling suggests it’s “increasingly likely” that CDR will be needed to avoid the worst impacts of climate change, the report concludes.
(Just yesterday, scientists at the University of California, Berkeley, published a study in Nature Climate Change suggesting that biomass could be burned and the resulting carbon emissions stored under ground. “Power generators could actually store more carbon than they emit and make a critical contribution to an overall zero-carbon future,” the scientists concluded.)
The problem, though, is that some fear that funding research into geoengineering techniques could dull enthusiasm for cutting emissions. “There is no 'silver bullet' solution,” McNutt says.
As for AM techniques, the panel says a “deliberative process” should govern how outdoor field studies proceed. “There are both theoretical and observational reasons to believe that albedo modification has the potential to act rapidly to offset some of the consequences of global warming at a relatively low cost,” the report says. Albedo research could include modeling studies, field research, satellite monitoring, and lab experiments.
Since 2006, when Nobel Prize–winning geochemist Paul Crutzen called for climate engineering research, scientific societies, a number of high-level panels and prominent lawmakers have endorsed federal funding for the field. But the United States has never established a formal mechanism to support studies of either type of geoengineering, and agencies have distributed just a few million dollars to researchers. The biggest funder of geoengineering research has been a nonprofit fund supported by billionaire Bill Gates, which has disbursed some $8.5 million for research and meetings since 2007.
Not that federal bureaucrats haven’t tried. In 2001, a draft internal report at the U.S. Department of Energy (DOE) called for a $64 million research effort on AM. But DOE official Aristides Patrinos said that he squelched the report because it didn’t fit administration priorities and that it would cause “adverse publicity, regardless of the merits of the research.”
Under President Barack Obama, climate engineering scientists continued to get the cold shoulder. In 2009, White House science adviser John Holdren told a reporter he had mentioned climate engineering research "in administration discussions." But when news reports suggested the White House was giving serious consideration to the idea, Holdren was forced to play down his words. That helped make it clear within the bureaucracy that the topic was taboo. On Capitol Hill, says retired congressman Bart Gordon (D–TN), a former chair of the House of Representatives science committee, support for climate engineering faced skepticism from the right—lawmakers who questioned climate science—and the left, from those who worried the idea would distract from a focus on cutting emissions.
It’s telling that the new climate engineering report didn’t come via request from federal science agencies. Rather, in 2013 the CIA requested the report. But scientists told NRC it should get civilian agencies involved. “You don’t want this topic militarized,” Keith says. Ultimately, NASA, DOE, and the National Oceanic and Atmospheric Administration together paid for roughly 10% of the report’s cost.
In recent years, scientists—often working on their own time—have published hundreds of theoretical or modeling papers on sun-blocking or carbon removal. But they’ve encountered numerous road blocks at funding agencies. When Douglas MacMartin of the California Institute of Technology in Pasadena approached the National Science Foundation for support on a modeling effort on AM, officials told him the work was too theoretical for the engineering division and too applied for the atmospheric science program. At DOE, Columbia University physicist Peter Eisenberger’s proposed demonstration of a carbon sucking machine fared poorly since the department’s carbon-capture program focuses on coal, he says.
Harvard’s Keith leads a team that wants to conduct an albedo experiment that involves releasing roughly one-half kilogram of sulfuric acid particles into the stratosphere to study its effects on ozone. “The agencies say they're waiting from guidance from [the White House Office of Science and Technology Policy], but OSTP says the agencies can do what they want,” he says. (OSTP declined to address Keith's comment, though a White House official said the administration would review the reports.) He hopes the new report might help end such gridlock.
Managing both research areas should be the job of the cross-agency U.S. Global Change Research Program, the authors of the NRC report write; embedding the work in mainstream climate science could yield benefits for both fields. Yet the authors warn that there could be “a chilling effect” on funding for fundamental atmospheric research if it becomes entangled in controversies over AM. That’s why some scientists prefer a dedicated research program for AM, so it doesn’t “contaminate” basic climate science.
Supporters of AM and CDR could both learn lessons from the United Kingdom, where in 2009 the Royal Society recommended a decadelong, £100 million research program into “geoengineering.” Six years later, three projects have been funded with a total of just £5 million. Issues over intellectual property mired one project, an outdoor experiment involving release of water vapor 1000 m above the ground, in controversy, before environmental concerns killed the project outright. “They screwed up their first shot,” says hydrogeologist Jane Long, formerly of Livermore labs in California. She hopes the U.S. experience will be different.
*Correction, 11 February, 4:21 p.m.: Due to the reporter's communication error, the published version of this story said that requests to OSTP for comment went unanswered. In response to questions, the White House said in a statement: "President Obama’s Climate Action Plan lays out a multitude of steps to combat climate change – with significant progress already made to cut carbon pollution, prepare for the impacts of climate change, and lead international efforts to address this global challenge. As with all credible and rigorous science that is policy-relevant, the Administration looks forward to reviewing the National Research Council’s reports."