Not clear if you don’t follow, disagree, or are just being tendentious. Of course, there is no instrumental information pre1850. I’d be the first to have an issue with JohnA or a similar type if they said something like that. (Like you JohnA is one who doesn’t follow a lot of the math.)

But the point is that you should use an ALL-PROXY curve then. Otherwise, you’re picking and choosing. If the proxies are so damn good that they’re reliable pre-1850, then they should be reliable post-1850. If THEY’RE NOT RELIABLE post 1850 (and you need to use instrument data then), then that casts doubt on their effectivess pre-1850 or even on their status as proxies.

All in order to ensure that I clearly point out the non-response responses on this thread (and others).

Best,

D

Eliza was better.

And your “As far as knowing a climate future for 50-100 years, just read earlier postings on this site and at RC, etc. ” I presume this is a misunderstanding on your part about scenario analysis. Surely scenario analysis is batted about in some circles, even to the point of using ” ” around scenario, as if it wasn’t serious.

As a scientist, you surely know the increasing use of scenario analysis in projecting future possibilities, as projections better account for surprise, whereas predictions do not. If’n it’s good enough for the military & biness, and increasingly scientific adaptive management (as a scientist, you know about this so forgive me for the obvious) it’s good enough fer me.

And to your “I prefer to treat everyone with respect in the hope of learning something. ” You’ll excuse me, as I’ve misinterpreted your comments elsewhere and here as being something rather different. Unless there is another PD somewhere who I’m confusing with you. If so, apologies.

But to your question, can you give me an example, today, of an optic that should be deplored? Knowing what we know in the future, that is, then looking back in hindsight at it. And to the ‘corner on knowledge’ point, it’s about the narrative and hiding the approach, and I believe my comments above frame your question accurately – that is: I’ve already commented on it here and elsewhere on this site beyond the point of prolixity. Namely, the CA framing of the underlying issue is a constructed narrative, and the type of non-response responses to addressing that narrative should be a clue.

Best,

D

Please Paul. Really.

You know full well there is no instrumental record to draw upon to have the same sort of data pre-ca. 1850s. That argument won’t fly.

And your ‘purporting to _know_ a future 50-100 years from now’…is a hoot. That strawman is so loosely wound it will ignite in a warm breeze. Surely there are better talking points out there, waiting in the weeds to be spotted by intrepid seekers.

Best,

D

In comments above, Hans Von Storch, who is certainly a little more informed than the three of us, effectively praises M and M for opening up a debate on the hockey stick. He goes on to deplore its use by the IPCC. Yet M&M are ridiculed by some on this site and particularly at Real Climate. Why? Do you folks have a corner on climate knowledge or science in general? Condescending comments and ad hominem attacks have no place in scientific debates and usually serve to display the unreliability of the author.

Like Von Storch I do not argue with the qualitative conclusion of the hockey stick. I am, however, highly disturbed at the (to me) unjustified quantitative implications. And as a scientist I think the stick is useless until the same type of data are used in the clubhead as in the handle. This kind of representation along with such things as purporting to know a future fifty to a hundred years from now does the debate no good.

Best,

D

After GRL in Feb 2005 the invitations began arriving and in April-May we did 11 talks in 7 cities, each time talking not just about decentered PCs, but (at length) about the policy questions we think the episode raises. We get criticised for speaking to Marshall/CEI events, but they’re the ones who showed enough interest to ask us to speak, and if you look at the transcript we did talk about the implications of understanding the inherent limitations of peer-review and assessment reports in the policymaking process. I used an invitation to give the keynote at the International Policy Forum on GHG Management at UVic in April 2005 to talk about bias-proofing the assessment process. That paper just came out in a journal.

So we’ve been trying to get the discussion going on the So? side, and it does seem to have a lot of traction with audiences. But in terms of engaging a larger audience the fact is there’s been no interest from magazines like SciAm or New Scientist, or TV science reporters, whose only spin on this issue is the valiant scientists hounded by the evil oil industry. For whatever reason it’s the conservative think tanks that invite us to talk about the institutional questions being raised. Pew, to take one example of a non-conservative think tank supposedly interested in climate policy issues, has not contacted us, nor have any government agencies, environmental groups, etc. I take that to mean they’re unaware or uninterested in the issue, or they don’t want to think about it. It’s not that we’re reluctant to get the discussion going about what-it-all-means-for-policy: the demand in many quarters is just not there.