Can Geoengineering Save Australia?

Australia's "worst flood disaster in living memory" threatens to swamp Brisbane, the country's third-biggest city, reports The Australian. "It might be breaking our hearts at the moment," said Queensland Premier Anna Bligh. "It won't break our will."

While floods hit northeastern Australia, southern Australia has been suffering through the worst drought in its history, one that has lasted a decade. In 2009, The Washington Post described the Outback as a "crematorium for kangaroos, livestock and farm towns."

"They're optimistically calling it a drought," says the veteran climate scientist Michael MacCracken. The drier conditions in Australia's major agricultural areas appear to be a result of a shift in the storm track to the south, he says: "It's not a drought. The Sahara isn't having a drought. It looks instead to be climate change."

MacCracken, who is the chief scientist at the nonprofit Climate Institute, has worked on climate issues since he wrote his PhD. dissertation in the 1960s, using an early climate model to investigate the possible causes of climate change. During the 1970s and 1980s, he worked under physicist Edward Teller, an early advocate of geoengineering, at the Lawrence Livermore National Laboratory. He then spent about a decade in Washington directing the government's U.S. Global Change Research Program and Climate Change Impact Assessment.

MacCracken is deeply interested in geoengineering. He was lead author of a section on geoengineering in the 1995 report of the IPCC (Intergovernmental Panel on Climate Change). So, when we met recently, we got to talking about Australia, and whether geoengineering could help there.

It's too soon to know, without further research, but MacCracken says research is exactly what's needed. In 2009, he wrote a 11-page essay called On the possible use of geoengineering to moderate specific climate change impacts [PDF, download].

It's about the potential for targeted, localized geoengineering -- the idea that geoengineering techniques, including solar radiation management and cloud whitening over the ocean, could be deployed, not to cool the planet as a whole, but to alleviate "specific consequences of climate change" that are causing significant negative impacts on the environment or society:

...Among the particularly severe consequences of climate change and emissions mitigation that geoengineering might be able to beneficially moderate are the rapid warming of the Arctic, the intensification of tropical cyclones and drought ...

For example, could solar radiation management be used to reduce the likelihood of extreme conditions in the subtropics, specifically, the likelihood that "wintertime storm tracks in the eastern Pacific will lock into patterns that contribute to sustained drought?"

Or could marine cloud whitening be used to limit the intensity of subtropical storms, by reducing the annual accumulation of energy stored in the upper ocean, say, in the Caribbean Sea, Gulf of Mexico or Bay of Bengal?