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Climate change: Sci-fi solutions no longer in the margins
2008-12-07
POZNAN, Poland (AFP) - With political efforts to tackle global warming advancing slower than a Greenland glacier, schemes for saving Earth's climate system that once were dismissed as crazy or dangerous are gaining in status. Negotiating a multilateral treaty on curbing greenhouse gases is being so outstripped by the scale of the problem that those promoting a deus ex-machina -- a technical fix that would at least gain time -- are getting a serious hearing. To the outsider, these ideas to manipulate the climate may look as if they are inspired by science fiction. They include sucking carbon dioxide (CO2) out of the air by sowing the oceans with iron dust that would spur the growth of surface plankton. The microscopic plants would gobble up CO2 as they grow, and when they die, their carbon remains would slowly sink to the bottom of the sea, effectively storing the carbon forever. Another idea, espoused by chemist Paul Crutzen, who won the 1995 Nobel Prize for his work on the ozone shield, is to scatter masses of sulphur dioxide particles in the stratosphere. Swathing the world at high altitude, these particles would reflect sunlight, lowering the temperature by a precious degree or thereabouts. More ambitious still is an idea, conceived by respected University of Arizona astronomer Roger Angel, to set up an array of deflecting lenses at a point between Earth and the Sun. Like a sunshade, they would reduce the solar heat striking the planet. Put forward in various forums and magazines, these so-called geo-engineering proposals have been dismissed by science's mainstream as a distraction or crackpot, with the risk of further damaging the biosphere. And even if such schemes are safe, they could cost many times more than reducing the heat-trapping pollution from fossil fuels that causes the problem, say these voices. But as the enormity of the problem looms ever larger, geo-engineering is shedding its untouchable status. "The notion of deploying geo-engineering research and even commercialising geo-engineering is enjoying a level of respectability in science policy circles that would have been unthinkable even three years ago," says Jim Thomas of Canadian-based watchdog group, ETC. One reason is "the level of panic" surrounding greenhouse-gas levels, which are growing at around three percent a year and are now more than a third greater than before the Industrial Revolution, says Thomas. Another, he suggests, is "an astonishing switch" by former climate sceptics and conservative lobby groups in the United States. After years of denial or contestation, these powerful forces have now suddenly accepted that global warming is a problem. They have seized on geo-engineering as a solution that would make it unnecessary to slap costly curbs on big polluters, he argues. The scientific establishment is still far from endorsing geo-engineering. Indeed, the UN's Nobel-winning Intergovernmental Panel on Climate Change (IPCC), in its landmark fourth assessment report last year, cautioned of the potential risk and unquantified cost of such schemes. All the same, geo-engineering is now getting a serious look by scientists and several names are cautiously saying it would be worthwhile to at least launch small-scale experiments to see how they pan out. This year, Britain's de-facto academy of sciences, the Royal Society, raised eyebrows when one of its journals published geo-engineering papers, which were balanced by a review by a top climatologist, Stephen Schneider of Stanford University. The Royal Society is carrying out its own analysis of geo-engineering, although it also makes clear that this act is not a sign of its approval. The report will be published in the first half of 2009. In an interview with AFP on the sidelines of the UN climate talks here, IPCC chief Rajendra Pachauri agreed geo-engineering "is getting a closer hearing, and you are getting people who are very respectable advocating it in several cases." "But the very fact that it's undergoing scrutiny is a good sign, because [it reveals] all the implications and all the side effects that you might be saddled with," he said. David Santillo, a senior scientist with the Greenpeace Research Laboratories at the University of Exeter, southwestern England, said scrutiny is fine, but it should not be taken as acceptance. "There is a danger that the more these things get talks about, the more people assume that there is some inherent legitimacy with the proposals that are being put forward. That simply is not the case," said Santillo.
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