On the Briefest Mention of “Emulating” MBH
Ans: Our report does not include the recalculation of MBH98 and MBH99. We were not asked nor were we funded to do this. We did not need to do a recalculation to observe that the basic CFR methodology was flawed. We demonstrated this mathematically in Appendix A of the Wegman et al. Report. The duplication of several years of funded research of several paleoclimate scientists by several statisticians doing pro bono work for Congress is not a reasonable task to ask of us.
And yet, he had reviewed MM05E&E. He had access to your code. He claimed to have run, at least, the GRL code, and should surely have looked at the EE code. He should have been aware that he did not need to duplicate several years of funded research. It didn’t take me long to get it running. But he said nothing. And so the talk went on to Wahl and Ammann
The Wahl and Ammann paper came to our attention relatively late in our deliberations,…
When you yourself spoke to the Committee you gave a presentation which included a five page prepared statement, and 14 slides. Your gave a two-page introduction. But you did not once tell them that you had actually emulated, with and without decentering, the results of MBH, the work in question. Nor did you say anything about it in your responses for the record, despite questions relating to difficulties that you had had in being able to replicate Mann’s work. Your response to one earlier question from Mr Whitfield [And I would ask Dr. Crowley and Mr. McIntyre or anybody else that wants to comment: the Wall Street Journal that has been referred to many times today says that Dr. Mann's methodology could produce hockey sticks from random trendless data. Is that a correct statement or is that incorrect statement?]:
MR. MCINTYRE. Well, let me answer that. That is true, and that is the one specific item that was verified by both panels, and both the NAS panel and the Wegman report specifically confirm that his methodology would produce a hockey stick from random data.
No qualification that you were talking about PC1, rather than a reconstruction, and no context to suggest that. You had already reproduced the actual reconstruction that was the well-known hockey-stick result that they would have believed you were referring to, and shown that the result was no more HS-like than with centered PCA. In your second address to the committee, you even managed to talk about Wahl and Ammann, and to say that your code reconciled to theirs, without making the obvious connection that both reconciled, or at least related, to MBH. The nearest it came was in this late exchange, which followed Wegman’s statement about not having done the calculation without decentering. It goes:
MR. STEARNS. Well, you know, I just want to give you your due here. We have heard in testimony that Drs. Wahl and Ammann have reproduced Dr. Mann’s work and shown your criticism to be invalid, and I guess–is this true and were your criticism erroneous? I will give you an opportunity to respond to that. MR. MCINTYRE. Well, a couple of points. First of all, the code that we used to emulate Dr. Mann’s work reconciles almost exactly with that of Wahl and Ammann. And so any conclusions that differ are not because of differences in how we have emulated the reconstruction. They think that certain steps are fine, we don’t. They have in my opinion not carefully considered the implication of bristlecones. Our codes reconcile so right now I am confident in our conclusions that if you remove the bristlecones you have a major impact on the final results. Last December, I met with Ammann in San Francisco and suggested to him that since our codes reconciled so closely that it would make sense if we co-authored a paper in which we set down the points that we agreed on, set down the points we disagreed on in an objective way so that we didn’t seem to be launching missiles at one another and creating more controversy. I said that we could declare an armistice for 6 weeks until we accomplished this, and if we didn’t get to conclusion everybody would go back to square one and that each of us could write separate appendices, say where we disagreed.
Well, you had time for that anecdote about Ammann, and even to say that your codes reconciled. But again, just the briefest mention of “emulating” MBH. Nothing about how well it corresponded to MBH, or what effect the decentering had. The question of whether decentering made a material difference was of obvious interest to the committee and Stupak asked about it directly. Wegman replied that he had not done a comparison. In fact your code that had that capability. You had an opportunity to point that out, and even volunteer your own results. You did not.
