Technological schemes to combat global warming are viewed as wacky or impractical. But they belong in the mainstream debate on climate changeby Oliver Morton / December 16, 2009 / Leave a comment
John Latham and Stephen Salter’s idea of spraying up sea salt is one of the proposed schemes that might cool the planet
If you want to know why many people take a dim view of geoengineering—a catch-all term for technological interventions to cool the climate system—look no further than Richard Branson. In October, Branson told the Wall Street Journal that “if we could come up with a geoengineering answer… then Copenhagen wouldn’t be necessary. We could carry on flying our planes and driving our cars.” But the idea that such schemes—for example, giant mirrors in space, artificially-brightened clouds or vast airborne Hoovers sucking up carbon dioxide—are a reasonable response to carbon emissions that can allow humanity to carry on polluting would strike most people as mad, bad or both. Doug Parr, chief scientist at Greenpeace, even said in 2008 that many of these ideas were “outright dangerous.”
If so, Richard Branson isn’t the only dangerous man. In recent months climate fixes have become quite the buzzy topic. In September 2009 the Royal Society released the first major report on the subject by a national academy of science. Around the same time “sceptical environmentalist” Bjørn Lomborg brought together five eminent economists to assess potential climate change solutions. The group concluded that research into geoengineering offered a better “cost-benefit ratio” than any other approach. The Intergovernmental Panel on Climate Change (IPCC) will discuss many aspects of the subject when the next of its hugely influential Assessment Reports appears in 2013, having given it only a few pages in its 2007 report. The IPCC’s chair, Rajendra Pachauri, has talked of carbon dioxide removal technologies probably being necessary in the long run. Less significantly, but with far higher visibility, economist Steven D Levitt and journalist Stephen Dubner’s book Superfreakonomics served up various unconvincing and breathless claims on the topic with a side order of needless error, leading to epic levels of vituperation in the blogosphere, and many delightfully snarky reviews.
To understand why this debate excites such passion, start with Branson’s idea that geoengineering could permit people to keep on burning fossil fuels. Here environmentalists and scientists agree that no geoengineering scheme can simply cancel out the effects of rising emissions. Greenhouse warming has distinctive effects on the climate that cannot just be reversed by reducing incoming sunlight; removing carbon dioxide from the atmosphere while continuing to emit more of it cannot in the…