The title of the report of the newly constituted "Nongovernmental Panel on Climate Change" (can we call them "Nopsy"?), the group of skeptics now meeting in New York City thanks to the money of energy and health-care corporations and some conservative foundations, is
That's a scientific statement. A scientific claim. It says, essentially, that natural forcings are more important than human forcings and can explain the rise in global temperatures of the last 30 years.
But I don't see a proof anywhere in their document. I don't see any of their models, or calculations of warming potentials and radiative forcings, etc. I see a lot of carping about the IPCC's science -- about, seemingly, everything the IPCC ever did -- but that's relatively easy to do.
But it doesn't constitute a proof. It you claim to have proven the Riemann Hypothesis and I claim that your proof is in error, that doesn't mean Riemann's Hypothesis is false. It just means there's a problem in your particular proof. I really haven't proven anything.
This isn't a perfect example, because it seems on the whole most scientists think the proof of AGW is fairly strong.
But Nopsy has made a scientific claim -- a quite strong one -- but has offered no proof whatsoever.
This just isn't how science is done. It's not science.