Well, Jonathan Adler, over at the Volokh Conspiracy, has looked into the matter and finds that there is a lot less fire than smoke here. What has happened is that the AEI, which has regularly criticized the IPCC, is assembling a critical review of its latest report and has issued a call for submissions. That's all. Adler makes the obvious point that, while the AEI volume will certainly be selective and biased, so too is the IPCC report it critiques.
If there were evidence that AEI was trying to get individual scientists to change their tune in return for large honoraria, there would undoubtedly be a story here. But there is no evidence this occurred. The general views of Professors Schroeder and North are well knowm to those who work in this area, and were unlikely to be swayed by ths offer (and they were not). More broadly, just as there may be financial incentives to write analyses desired by corporate funders, there are also financial incentives to tailor research projects and findings to increase the likelihood of receiving government grants. This is why I believe scientific studies should be analyzed on their merits, not the source of funding.Amen [emphasis mine]. This kind of ad hominem attack is all too common.
Read Adler's commentary here.
David Frum expands on the matter:
1) AEI is not, as the enviros claim, a "lobbying group."
2) AEI compensates its contributors; so does the Guardian; so does the UN; so do left wing think tanks; so does the Kennedy School. What is more, the UN pays its contributors a lot more than does the AEI.
3) It is dishonest to portray, as the activists do, the struggle as being between "Big Oil" and the "environment." Oil companies will not pay the costs associated with the reforms; the public will.