Barrett basically dismisses any possible negative costs associated with “geo-engineering” with the wave of his hand.

the reality is that “geo-engineering” is (at best) an ill-defined hodgepodge of techniques whose negative environmental ramifications are largely unknown that this point.

I’m aware of the fear that the public has regarding genetic engineering but the science has made great strides in the last ten years and the public has been able to swallow nukes as a deterrent even when Mutually Assured Destruction was the theme.

Genetic engineering could get the world out of this mess once it’s taken seriously and major proportion of the leaders in the field get involved (I don’t mean Monsanto). Genetically-engineered crops could be producing ethanol, sequestering carbon, and eliminating other risks.

I’m wary of engineers as arbiters of climate change – industry & engineers got us into this mess in the first place, let’s give others a chance to undo the problem. Changing our climate with mirrors in space is a bad idea. Let’s work on the problem down here on Earth first!