The claim by the Watts up with that blog that statements in a leaked draft of the upcoming IPCC assessment report is "game-changing" is not wrong scientifically, it makes no logical sense.

The supposedly game-changing evidence - that there may have been a great change in the sun's impact on the climate than previously thought - is just a classic case of rhetoric trumping data.

Notice there are no numbers in most of the quotes that Alec Rawls pulled from the IPCC report. Just because something is greater than previously thought does not mean it is a lot greater or a lot more important [besides, as Skeptical Science nicely reminds us, Rawls explanation makes no sense].

A couple years ago, I discovered that I am actually half an inch taller than what I had previously thought, a funny thing to discover at my age. That doesn't mean I'm going to try out for a NBA team, though I do suspect my 4-19 hometown Toronto Raptors could use some help at small forward.

The science is almost irrelevant here. The real issue is the nature of the IPCC. It does not conduct original research. The IPCC reviews and assesses the scientific literature on climate change through an exhaustive multi-year process. If there was some "game-changing" discovery about the sun's impact on the climate or any other key issue in the IPCC draft reports, that discovery would already have been reported by scientists in the literature that the IPCC reviewed.

At the absolute minimum, the discovery would be have been reported in scientific papers submitted to a journal before the long-passed deadline for the IPCC, and if the papers were by now published or publicly available, the contents would have been presented by the authors at prominent scientific conferences like last week's AGU meeting, which is so well reported that "AGU" was actually trending on twitter for half of the week.

If there was some "game-changing" discovery, we probably would have already heard about it in the news and we certainly would have heard it on blogs like Watts up with that.