Assumptions are always key in decision analytics/rational choice models (as in everything else?), but I give the authors credit for being open about it: "this analysis employs pure subjective probability estimates, assigned by the authors using our best judgments and with a desire to illustrate the potential interactions and interdependencies of the levers, uncertainties, and measures of merit" (p. 27). This is more than can often be said.
Josh On Fri, Apr 29, 2011 at 10:50 AM, Ken Caldeira < [email protected]> wrote: > > The RAND report makes the the curious claim that "*U.S. policymakers might > prefer No Norms to Strong Norms or Ban if they believe that SRM technologies > are unlikely to work but that climate change could prove catastrophic.*" > > The answer you get depends on the assumptions you make. > > Their logic is explained on page 35-36: > > *No Norms generally works best for the conflict measure because it is the > U.S. policy that > makes it least likely that a geoengineering system will ever be deployed. No > Norms has high > regret for three of the four measures when geoengineering is likely to > succeed. But this policy > generally performs well at reducing conflict whenever international > conditions are unfavorable > for agreement (second, fourth, sixth, and eighth rows in Figure 3.4). This > result owes to our > assumption that No Norms can lead to conflicting and thus failed > geoengineering tests. This, > in turn, leads to fewer deployments even under catastrophic climate change. > * > > > ---- > > From the introduction (page xi - xii): > > *Under Strong Norms, the U.S. government would encourage the establishment > of international > norms to govern geoenginering research. Under Ban, the United States would > promote > a prohibition on any geoengineering research. Under No Norms, the United > States would > actively discourage the formation of norms governing research. A comparison > of the performance > of these three strategies across many plausible future states of the world > suggests that, if > U.S. policymakers believe that some type of SRM technology is possible, > they ought to prefer > the Strong Norms policy to No Norms or Ban. Under such conditions, this > option outperforms > the alternatives because it increases the likelihood of a successful > deployment in those > cases in which geoengineering proves useful. It also reduces the likelihood > of failed deployments > by nations struggling to respond to serious climate impacts. > > If U.S. policymakers believe that no SRM geoengineering technology is > likely to succeed, > they might prefer the Ban or No Norms policy to Strong Norms. The Ban > policy appears the > better of the two if policymakers believe that climate change is highly > unlikely to prove catastrophic. > Under such conditions, this option reduces the risks of > overconfidence—deploying a > geoengineering system that passes its tests but fails in practice. This > option also increases the > likelihood of reaching an international agreement to reduce greenhouse gas > emissions. > In contrast, U.S. policymakers might prefer No Norms to Strong Norms or > Ban if they > believe that SRM technologies are unlikely to work but that climate change > could prove catastrophic.** > Under such conditions and a Ban policy, some other nation might defy the > prohibition, > test, and then deploy a SRM system that subsequently fails. The absence of > research norms > might lead to uncoordinated tests by several nations, undermining the > ability to learn from any > test. Thus, in this case, the absence of research norms might prove more > effective than the Ban > at preventing unsuccessful geoengineering deployments under dire > circumstances.* > > ___________________________________________________ > 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, Apr 29, 2011 at 6:48 AM, Josh Horton <[email protected]>wrote: > >> Speaking of circling, while this is a very interesting analysis, its >> results seem tautological. There are 2 main conclusions: >> >> 1. "If U.S. policymakers believe that some type of SRM technology is >> possible, they ought to prefer the Strong Norms policy" (p. 39). >> >> 2. "If they believe that successful SRM technology is unlikely, U.S. >> policymakers might prefer the Ban or No Norms option to Strong >> Norms" (p. 40). >> >> In other words, if the technology works, support research, if not, >> don't bother. But these beliefs will be based on research findings. >> Not sure how much this adds to the debate. >> >> >> Josh Horton >> [email protected] >> >> >> >> On Apr 21, 4:20 pm, David Keith <[email protected]> wrote: >> > RAND is circling back to this topic, interesting to compare to RAND >> reports of the1960s >> > >> > -David >> > >> > RAND, TR846, Lempert, 2011.pdf >> > 622KViewDownload >> >> -- >> 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]. 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