John Fleck has an interesting article about confusing the two questions: 1) is there significant AGW? and 2) should very much be done about it? I missed it when it came out but fortunately Revkin linked to it.
John argues (presumably somewhat under the influence of RP Jr.) that the latter question is legitimately an open one, that substantive information already in existence is insufficient to settle it.
The primary audience of this blog is people who disagree with John on the second point. That is, we agree that the focus of the discussion should move away from physical climatology, the focus on which is a deliberate red herring on the part of people who oppose action. We disagree with anyone who suggests that it is a marginal or unproven case that such action is necessary. This requires us to broaden the conversation from physical climatology to the whole structure of modern society, which makes it incredibly interesting and incredibly difficult to make a case. It's immensely frustrating that there is still a focus on the physics part; regardless of what you may hear it is really a slam dunk by now that contemplated levels of CO2 are climatically significant.
So, one of the questions that most irks me is how and why we are still spending so much time on the first question. On the other hand, while I am convinced that only one answer is possible to the second question once present evidence is accounted for, it doesn't immediately follow from the first. Several steps are missing between a significant change and a policy imperative, but they are all quite solid.
One way of looking at it is as follows:
1) Are humans changing the composition of the atmosphere?
2) Does that change have observable consequences already?
3) Given current human behavior, what is the likely trajectory of those consequences into the future?
4) Are those consequences morally acceptable?
5) If not, what action should be taken?
It's hard to avoid a doubt whether question 4 is admissible. Some will prefer to substitute "Are those consequences economically acceptable?" I find this substitution unacceptable for various reasons.
Aside from question 4, a conclusion that dramatic changes need to be made is extremely solid. So why aren't we discussing point 4? Well, because that would get us thinking seriously about what society is for and what life means. All sides seem intent on avoiding the question of what our moral obligations are and how we should think about them. Focusing the conversation on a basic and unsurprising and incontrovertible result in climate physics at the expense of a discussion of who we are and how we should make collective decisions is a sign that social maturity has ebbed drastically.
So, as a refinement of John Fleck's argument, I would say that it's true that all of these are typically conflated. The extent to which we are discussing 1 and 2 to the exclusion of 3 and 4 and 5 is simply a mistake. On this point I agree with John.
On the other hand, I believe that we disagree in that I think the evidence on points 3 and 4 is overwhelming, but my position of #4 (and the implicit position on #4 of most who agree with me) is not based on an explicit social consensus, for once we get to the meta-question of what the right question 4 is, we are in a deep quandary.
We need to adjust to a finite world or that world will adjust us for us. The decisions involved are not well-represented in an economics that models labor and capital and real estate as first order inputs but consumable resources as a correction.
The press is not so much afraid to discuss this as utterly incapable (what news slot does it come under?), and advocates on all sides (except for market libertarians for whom it is all too simple) ignore the elephant altogether. Consequently the public is utterly confused about the choices imposed by the transition that is upon us, one that is as great as any in history.