In Judy Curry’s post on Climate Etc titled
“Does the problems with the IPCC mean that WG1 science is incorrect? Not necessarily, but I agree that a “new trial” is needed. WG2 and WG3 reports pretty much belong in the dustbin, as far as I can tell.”
WG1 is incorrect because it suffers from “sins of omission”. I documented this in the Appendix to my Public Comment
Pielke Sr., Roger A., 2008: A Broader View of the Role of Humans in the Climate System is Required In the Assessment of Costs and Benefits of Effective Climate Policy. Written Testimony for the Subcommittee on Energy and Air Quality of the Committee on Energy and Commerce Hearing “Climate Change: Costs of Inaction” – Honorable Rick Boucher, Chairman. June 26, 2008, Washington, DC., 52 pp.
The 2007 IPCC WG1 report ignored peer-reviewed papers which conflicts with their narrow focus on the radiative forcing of CO2 and a few other greenhouse gases.
In our paper
Pielke Sr., R., K. Beven, G. Brasseur, J. Calvert, M. Chahine, R. Dickerson, D. Entekhabi, E. Foufoula-Georgiou, H. Gupta, V. Gupta, W. Krajewski, E. Philip Krider, W. K.M. Lau, J. McDonnell, W. Rossow, J. Schaake, J. Smith, S. Sorooshian, and E. Wood, 2009: Climate change: The need to consider human forcings besides greenhouse gases. Eos, Vol. 90, No. 45, 10 November 2009, 413. Copyright (2009) American Geophysical Union
“….the 2007 Intergovernmental Panel on Climate Change (IPCC) did not sufficiently acknowledge the importance of…other human climate forcings in altering regional and global climate and their effects on predictability at the regional scale. It also placed too much emphasis on average global forcing from a limited set of human climate forcings. Futher, it devised a mitigation strategy based on global model predictions. ……policy makers must be made aware of the inability of the current generation of models to accurately forecast regional climate risks to resources on multidecadal time scales.”
To this list, based on new knowledge, including what is presented on Judy’s weblog, the role of natural climate variability, even in terms of global averages, needs to be elevated in importance.
The 2007 IPCC WG1, in my view, was a failure in the assessment of the understanding of the human role in the climate system, as well as the extent to which the natural forcings and feedbacks influence the climate.