The determination of the social cost of carbon (SCC) as made by the Interagency Working Group (IWG) and detailed in the May 2013 Technical Support Document (updated in November 2013) is discordant with the best scientific literature on the equilibrium climate sensitivity and the fertilization effect of carbon dioxide — two critically important parameters for establishing the net externality of carbon dioxide emissions, at odds with existing Office of Management and Budget (OMB) guidelines for preparing regulatory analyses, and founded upon the output of Integrated Assessment Models (IAMs) which encapsulate such large uncertainties as to provide no reliable guidance as to the sign, much less the magnitude of the social cost of carbon.
The OMB should act not just to revise the current determination of the SCC, but to suspend its use in all federal rulemaking. It is better not to include any value for the SCC in cost/benefit analyses, than to include a value which is knowingly improper, inaccurate and misleading.
We highlight some of the major flaws in the current SCC determination in our following comments.
