Correct Ken. But the more relevant question is a political science question: what would the impact be of a substantial SRM program on various countries' willingness to undertake a serious emission mitigation program. We cannot assume that these two societal decisions are independent. Personally, I don't think the answer is at all clear whether consideration of SRM would increase or decrease a country's commitment to GHG mitigation efforts and I suspect the answer would differ substantially from country to country.
I do think there is a serious risk that "putting SRM on the table" could be embraced by some policymakers as an alternative to GHG mitigation and that would be a very unfortunate result. But I also think that it will not be an effective response by those of us who worry about such an embrace to argue against any SRM research programs. Rather, we should be thinking about how to design the conversation regarding SRM research to minimize the probability that it will be viewed as something that should be pursued instead of GHG mitigation. David -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Ken Caldeira Sent: Friday, May 13, 2011 8:49 AM To: [email protected] Cc: [email protected] Subject: Re: [geo] Re: New law review symposium issue on geoengineering This may be a distinction without a difference, but there is no long-term commitment to SRM once begun. Within a few years, the added aerosols will be out of the atmosphere. The long-term commitment comes from the long atmospheric lifetime of the CO2 concentration perturbation. Thus, the commitment to intergenerational transfer of risk seems to be a result of the CO2 emission, not the stratospheric aerosols. Given some specified future CO2 emissions trajectory, would future generations prefer us to keep the Earth cool or let it get warm? In either case, we are handing them a perturbed climate system. I do not think we can answer a priori which action on our part future generations are more likely to prefer. In either case, we are handing future generations an "unnatural" state of affairs. I would assume that future generations would prefer us to hand them a world with "natural" levels of atmospheric CO2 and planetary temperature. However, if CO2 levels are high, the question of whether they would prefer a hot world without stratospheric aerosols or a cool world with stratospheric aerosols cannot be answered with armchair philosophizing. We need scientific research to help evaluate the risks of each course of action. ___________________________________________________ Ken Caldeira Carnegie Institution Dept of Global Ecology 260 Panama Street, Stanford, CA 94305 USA +1 650 704 7212 [email protected] http://dge.stanford.edu/labs/caldeiralab @kencaldeira On Fri, May 13, 2011 at 7:17 AM, Michael Hayes <[email protected]> wrote: > One last thought, Wil. > Don't bet on rare combinations! Casinos make Lots of money of those.....for > a reason! > Michael > > -- > You received this message because you are subscribed to the Google Groups > "geoengineering" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]. > For more options, visit this group at > http://groups.google.com/group/geoengineering?hl=en. > -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en. -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en.
