Ken Caldeira of the Carnegie Institution for Science, US, has thrown his hat into the ring by giving a talk entitled "We don't need a 'geoengineering' research program" at the American Geophysical Union Fall Meeting last December. environmentalresearchweb caught up with him in San Francisco to find out more.

We don't need a geoengineering research programme
Ken Caldeira on how huge bureaucracies can take on a life of their own.
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Caldeira believes geoengineering would be better served by the expansion of existing research streams, such as the removal of carbon dioxide from smokestacks in power plants, no-till agriculture and other soil amendments, and stratospheric particle and chemistry research based around volcanoes and the ozone layer. Activities such as whitening clouds over the ocean, meanwhile, could be carried out by those who are already studying marine clouds.

Geoengineering techniques fall roughly into two groups: those that aim to remove carbon dioxide from the atmosphere, and efforts to reduce the amount of solar radiation reaching Earth. According to Caldeira, carbon-dioxide removal techniques, with the possible exception of ocean fertilization, are largely uncontroversial.

When it comes to sunlight reflection, Caldeira is in favour of environmental science studies but against work that strays into the engineering development of implementation techniques:

Take the engineering out of geoengineering
Caldeira on why society should decide whether to implement geoengineering technology before engineering development goes ahead.
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While geoengineering is not yet on most people's agendas, future events could cause a radical shift in public opinion, said Caldeira. In turn, this would put pressure on politicians to implement the technology. But what is best from a political point of view is not necessarily best for the environment:

Politics versus environment
Caldeira on the temptation to take actions that will show results within a political cycle, and why slow is best.
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As well as altering the environment, geoengineering will affect human systems such as agriculture. This gives poor people in tropical countries perhaps the biggest incentive of all to implement geoengineering, said Caldeira, as crop yields in the tropics are more likely to be badly affected by heat stress than those in northern climes, where yields may even improve.

Developing gains
Caldeira explains why leaders in tropical countries could have the greatest motivation to deploy geoengineering systems – namely famine.
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But are countries likely to go it alone when it comes to geoengineering, without complying with any international agreements that may be set up? On this point, at least, Caldeira is relatively optimistic that the forces of blame and destruction could prove positive.

Taking sides
Caldeira on why the risk of unilateral action on geoengineering may have been greatly overstated.
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