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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?
Regarding Graham's comments,
Regarding Graham's comments, it is important to note that the question is not is geoengineering good or bad on its own as it was back in the 1950s and 1960s when there were proposals to use such approaches to make a supposedly better world. The question now is whether we have greenhouse gas induced climate change with or without geoengineering--with the intent of any intervention being to try to keep the climate close to what it is or recently was. Human-induced climate change is, as IPCC describes, going to cause major changes in climate and sea level (and ocean acidification and approaches I propose don't deal with that--only mitigation or enhancing sinks/scrubbing CO2 can deal with that, and we need to do this--but this won't moderate climate change except over the long term--except see http://www.climate.org/topics/climate-change/maccracken-proposal-north-s...).
With respect to human-induced climate change with intervention, with research, there may be a capability to moderate the worst aspects of climate change, helping to make adaptation more possible until mitigation can take sufficient effect. Clearly, there will also be some unintended, undesired side effects (there is no such thing as a free lunch), but these combined with moderated global warming may be less severe. Regarding relative uncertainties, it seems to me that, with a bit of research, they might well be less significant with intervention (as the climate will be staying, if the approach works, closer to present conditions, than if there is not intervention, where there is great worry about passing thresholds as the climate rapidly heads into more and more unprecedented conditions. For all of this, we need research to explore possibilities and to strengthen the discussion with the public and policymakers of the consequences and implications and alternatives.
The only other comment I'd make is that, while there are uncertainties, we have had a lot of experience with increased loadings of sulfate aerosols--especially through the middle and latter half of the last century. Much was learned about air quality and acid deposition impacts, but there is lots more to learn about what the climatic implications were. Proposed interventions would likely require an amount of emissions within what we have already experienced--at least in some regions, but lots to learn. And brightening the clouds or the surface can also draw information from the past. So, much to learn, and some possible analogs to look at, and to help in public understanding and evaluation.. But yes, we allwish it were not necessary to be considering such steps.
Interesting article, I like
Interesting article, I like that mitigation is noted as the prefered strategy, though mentioned too late.
I don't believe this story is well balanced in presenting geoengineering. The author makes geoengineering look to be nothing but positive and doesn't even allude to the fact that what's being proposed is disruption of the earth's climate system by artificial means.
We have no idea what atmoshpereic injections of sulphides, some of which are regulated airborne pollutants, or other geoengineering concepts would do over the long term, there might be short term positive impacts, but on a massive scale we could accelerate climate change.
The complexity of our climate system is not well understood and messing with it could have disaterous consequences. Perhaps this why the US and other countries are not considering geoengineering? Though I do applaude the author for noting that broader climate change strategies are needed.
As a climate professional, geoengineering scares the heck out of me.
Sincerely,
Graham