Bruce Sterling refers us to a recent paper covering the possibilities for finding technical schemes for mitigating the effects climate change, with his witty and spot-on commentary in (((triple parens))) below:
"Reducing global greenhouse gas emissions by the amount (say 50%) which may be necessary to avoid excessive climate change, will be very difficult. If combined with significant convergence internationally, it will moreover require the developed countries to reduce their emissions by much larger proportions, such as 90% (for the USA) and 80% (for Europe). Many people feel that it is very unlikely that such reductions can be achieved just by improving energy efficiency and reducing carbon intensity by using renewable sources of energy. (((Yep, it sounds pretty tough... I guess we'd better just fold our hands and die from this civilizational inadequacy of ours... Oh wait, maybe we techies can invent some source of hope, however farfetched!)))
"Specifically, conventional approaches may not be sufficient regarding either their magnitude and their time-scale. Because of the urgency of implementing climate-change management, more innovative approaches to the mitigation of climate change are likely to be needed. (((Let's rephrase this, shall we? "Although we can't find the political will not to cook our own planet, we might, while cooking, be able to invent some weird way to avert some of the consequences.")))
Still, while trying to mitigate a full-blown climate-disaster-in-progress is idiotic for all the reasons Bruce cites (and more he neglects), this paper itself is worth a look if only as a means of understanding what's theoretically possible (and what some are almost assuredly going to advocate).
Giant space mirrors. Really. Put them in space, reflect away an appropriate amount of solar radiation, and if the side effects prove to be unacceptable, take them down again. It's one of the few bits of heavy duty climate engineering which is (probably) fully reversible, and it directly addresses the source of global warming: trapped solar energy.
$0.02 but you heard it here first :-)