I, for one, enjoyed your post Roger.

BTW, I second Kevin V. comments about Paul.

But to the “substance” of the post, such as it is. The statement

“The actions that we take on climate change should be robust to (i) the diversity of scientific perspectives, and thus also to (ii) the diversity of perspectives of the nature of the consensus. A consensus is a measure of a central tendency and, as such, it necessarily has a distribution of perspectives around that central measure (1).”

Is either a set of oxymorii, so vague as to be useless, or a major mistake. First of all, if something is sensitive to the ENTIRE range of a large set of studies, then it is overly broad and useless for policy purposes. It over-emphasizes outliers. The purpose of critical reviews such as IPCC is to narrow the range to the best estimates (which themselves can have a range, but a much narrower one). You can, of course, always drown policy makers or readers of a blog in a sea of references. You can actually do the same to scientists (you just need more of em). OTOH, those looking for expert guidance need to have the field narrowed so they can move on to the next thing, be it further studies or policy initiatives. The policy advocated here is merely a variation of “further study for everything we don’t want to have to do anything about” (scary quotes). By keeping everything open, nothing is ever settled. How “useful”.

‘Roger – I’m likely NOT a ‘you folks’ -

Crazy day, but not too crazy to notice kevin v’s spot-on comment and to write:

what kevin v said.

Best,

D

With a very few exceptions, the commenters here are far and away the most substantiative commenters I’ve seen in the science blog world (even the implacable Mark B gets his props, much as it might hurt me to admit it 8-). Your comments stand out as seeming substance-free but vendetta-laden. Can you please explain the vendetta or else just play along with everybody else and add some original insights into the discussions without being catty and insulting?

A cursory look at the public discourse will reveal the extent of the subjugation of the consensus term, and the liberal (ahem) use of scare quotes.

HTH,

D

On the questions, I generally agree with Eli’s response, but would add that of course the TAR had to take a very conservative approach, especially since comparatively little was known at the time regarding the magnitude of other anthropogenic forcings, mainly aerosols and land use changes. It’s a mistake to look at those numbers and imagine that the likelihood of the warming being from non-anthropogenic causes could be the complement of them. Rather, I would imagine it would be something close to or maybe even at zero. In any case, this is an odd time to have this discussion as it is obvious to everyone paying attention that the science supporting an AR4 conclusion of very near 100% anthro has been in place for quite some time. The “very near” is there only to account for a possible but clearly small positive solar forcing and an unlikely but not entirely excludable positive change in magmatic forcing.

Nuances aside, I can’t really answer your three questions directly since you substituted “most” for “majority” and I’m not sure what that means. But if you had left it at “majority,” my answers would be yes, no and no.