For the purpose of this note, I'll stipulate that global warming is happening without arguing why. The question for science would be whether it has a positive feedback loop, as it would if rising temperature releases, say, 10% of the carbon locked in permafrost. Given the wild temp excursions in geologic time scales -- "snowball earth" vs. the Cretaceous (when there was no ice at the poles) -- it is reasonable to imagine that some excursions have a phase where the feedback is positive and thus if the temp heads either north or south its velociity will, for natural reasons, accelerate as the excursion grows more extreme. That implies that the present time is an unstable equilibrium, thus our imapct, whatever it is, seems likely to be an initiator or a potentiator but not a cause in the classical sense of, say, a dose-response curve. Put differently, I don't believe that we (humans) can push the climate to a place it has not been before, but we can change the clock. One might then ask what government has your confidence in its being capable of managing a comprehensive program of compensatory global cooling and what powers would be required to enforce same? What this topic has to do with this list is unobvious. --dan