The information necessary for such an assessment may be found online--Jim Prall's "Most-Cited Authors on Climate Science" web page (http://www.eecg.utoronto.ca/~prall/climate/) allows you to compare the credentials and citation records of the 619 IPCC AR4 working group 1 (climate science) authors to those of signatories of various public declarations on climate change, pro and con.
This information supports the conclusions of the CFI "Credibility Project"--there are very few legitimately credentialed climate change skeptics. Further, many of those identified as skeptics who are legitimately credentialed accept that there is anthropogenic global warming, though they question its extent and impacts. I recently asked Robert Balling of ASU, who appears on climate skeptic lists, where I as a layman could find the best consensus information about climate science. His answer: in the IPCC AR4 physical science report.
It should also be noted that climate skeptic John R. Christy was an IPCC AR4 wg1 lead scientist.
It's no surprise that there are numerous scientific organizations that have officially endorsed the IPCC's position on anthropogenic global warming, including the national academies of many countries, and none that have rejected it.