Analysis: "Climate scientists… have been overconfident in their models."

Over at Watts Up With That? a new, soon-to-be-published paper is being discussed that provides analysis of the models used by climate “scientists” such as Dr. Mann and the rest of those guys at places like the East Anglia CRU. The paper doesn’t approach this issue from the question of whether or not the proxy data used by Mann, et al, is of sufficient quality or by noting that the original data was “adjusted” by Mann’s team and then destroyed. Rather, it looks at the statistical modeling used by Mann’s team to determine whether or not the model itself is consistent with the predictions it’s making given the data used.

Short answer: no. By applying a bayesian backcast method (well understood and widely used in this kind of analysis) they determined that the data does not produce the sharp spike of temperature now well-known as the “hockey stick.” Check out the graphs side-by-side at Mr. Watts’ site at that 1st link I’ve provided.

The paper itself is scheduled to be published in the next issue of the Annals of Applied Statistics but you can view the submitted paper here. (Download it here, too.)

In short, the authors found that the proxies used by Mann and analyzed with their backcast don’t predict the temperatures any better that a randomly-generated series of numbers. Furthermore, they don’t predict the steep incline Mann’s hockey stick shows. In their conclusion, they state, “[c]limate scientists have greatly underestimates the uncertainty of proxy based reconstructions ahd hence have been overconfident in their models.”

Watts reports that certain AGW proponents are actively deleting any comments entered on their blogs and forums that so much as mention this paper which, as he says, “tells you it has squarely hit the target.”

A question of significance in this matter is whether Mann and his team knew about these flaws – or became aware of them amid the questioning of their findings – and simply decided not to reveal that knowledge. If so, then they have deliberately misrepresented the situation even while making greater demands for both public funding of their continued “research” and for policy changes affecting us all. This is the question being pursued by Virginia’s Attorney General Ken Cuccinelli who is seeking access to files used by Dr. Mann at the University of Virginia. Mann received tens of thousands of dollars in taxpayer funds to pursue his work and the question of whether he committed fraud by misrepresenting the truth in his applications for those funds needs to be answered. UVA is attempting to block Cuccinelli’s access to those records. Their attempt to have his request summarily dismissed failed and a judge heard arguments on the matter on Friday. He is scheduled to rule on the matter in the next 10 days.

Whether AGW is correct or not remains an open question, although given that historical records indicate temperatures at or exceeding today’s levels were seen prior to any industrial activity on man’s part it’s not looking good for the AGW team. What we can do about it – and whether we should do anything about it – is a question that can only be answered by real and accurate information about the situation. History is rife with examples of human interference in local environments that began with a woefully incorrect understanding of the situation as it was. Politics needs to be removed from this debate and the matter decided upon not with an eye toward bringing about a desired social state or curtailing practices some of us find offensive but with a goal of understanding the situation as it is. With that understanding, actions can be decided upon in as great a confidence as our limited abilities can provide.