Devastating criticism of the IPCC from a guy who contributed to all five IPCC Assessment Reports.

It wasn't "science" but advocacy. They knew the results they wanted and found the data to support their pre-determined conclusion.

I feel rather unconfortable about using not only unpublished but also un reviewed material as the backbone of our conclusions (or any conclusions)...

Essentially, I feel that at this point there are very little rules and almost anything goes. I think this will set a dangerous precedent which might mine the IPCC credibility, and I am a bit unconfortable that now nearly everybody seems to think that it is just ok to do this.