Roger Pielke requested op ed’s from Mann and myself as to why anyone should care about the hockey stick. Mann refused to participate. I wrote one, Ross drafted a version. Because I’ve been travelling, I didn’t have time to try to reconcile our views, so we each send in versions which can be read Ross here and me here. (archive) Kevin Vranes has written his own commentary.
There have been a few comments from realclimate coauthors (William Connolley and Rasmus) in the comments, which are worth reading through and both Ross and I have posted up supplementary comments as well.
I apologize for the interruption. The blog hit its storage maximum and it took a while to diagnose that this was causing the problem . There were then problems restoring which I won’t elaborate now, all of which was exacerbated by slow turn times from the hosting company. Some comments may not have survived the restore and, if so, I apologize.
A couple of months ago, after getting nowhere with Moberg on same peculiarities in some data sets (see right category Moberg et al ), I filed a Materials Complaint to Nature discussed here. There have been some developments on this.
Readers may recall that, on a previous occasion, in connection with MBH98, Ross and I filed a Materials Complaint with Nature and, as a result, Nature required the authors to issue a Corrigendum.
A Concern: Ken Fritsch makes the following comment:
While your efforts to avoid the implication of censoring of opposing views should be commended, I am not a little distracted by the noise levels that I find come from (a) personal debates that frequently do not add to the knowledge base of the specific topic at hand, (b) posters who seem to come to the discussion with the intent of having their feelings hurt or to uncover evidence of a bias towards them and/or people with their points of view, (c ) posters who raise to the bait of these posters and thus contribute to wasted space (ad hominem ad infinitum), (d) posters who merely seem to want to let skeptics and agnostics know at every opportunity that the circumstantial case is closed on AGW and only fools would question what they surmise to be an overwhelming and proven consensus from the climate scientists, (e) those who make their personal cases against AGW with little or no evidence to back it up and (f) those who seem to want to show that they can turn your efforts as a critic of some sometimes sloppy and vague climate science publishing back on you.
There are lots of places in the world where people can discuss general issues of AGW, but not many places where technical discussions of proxies can take place. I’m getting really tired of technical threads getting hijacked. If there’s a thread on Lago Paco Cocha or Quelccaya Plant Deposits or a technical topic, please do not hijack for general fuming. If anyone wants to vent, vent on the National Post Op Ed sort of thread and stay away from the technical threads. In order to encourage this, I am warning that I may start deleting off-topic posts on the technical threads. Yeah, yeah, I’m sure that somebody will claim that they are being censored, but I’m going to try it and see if the noisiness will reduce. Continue reading →
Jones et al. [1998] makes the reasonable policy that proxies should be validated against gridcell temperatures as evidence that they are temperature proxies, noting that this is not always done. This policy is endorsed in Jones and Mann [2004], who note that not all multiproxy studies had observed this policy, presumably including MBH98, which included precipitation measurements in the dataset.
As an exercise, I attempted to replicate their results, as reported in their Table 4, against the present HadCRU2 gridcell temperatures. A few points are illustrated in the replication tables – one for their annual series and one for the decadal averages. First, many of their reported results cannot be replicated, including the correlations for some well-known proxies. Second, I’ve done calculations to yield a t-statistic, which is easier to determine significance than a correlation statistic. For independent residuals, a t-statistic of about 2 is significant. For autocorrelated series and for cherrypicked series, it’s higher, but I’ve not done those calculations here, contenting myself with illustrating versus OLS significance. I’ve marked in bold red examples where the t-statistic is insignificant or where there are big declines in replication versus actual. Also I’ve calculated the Durbin-Watson statistic, which is one measure of autocorrelation in residuals, used to test for spurious regression. Granger and Newbold [1974] discussed here took the position that any model with a DW<1.5 is misspecified. These are also marked in bold red. Not much survives. Continue reading →
I mentioned here that I would be presenting at a poster session at the U.S. Climate Change Workshop (Nov 14 evening, Crystal Gateway Marriott, Arlington Virginia). Poster pdf’s are supposed to be in tomorrow. Here’s a draft. I’d appreciate any comments. Obviously many of the points are ones that readers of this blog are familiar with.
Obviously there are any number of problems with all these studies. Here I’m picking a couple of the more interesting ones, which have a pretty important knock-on effect.
Montgomerie and Birkenhead have an interesting discussion of scientific misconduct here (scroll to page 16), starting with Mendel.
Bob Montgomerie and Tim Birkhead, 2005, A Beginner’s Guide to Scientific Misconduct, ISBE Newsletter, Vol. 17(1) May 2005, 16ff. URLhttp://www.behavecol.com/pages/pdf/Montgomerie&Birkhead_vol17%281%29.pdf
Yesterday we had an all-time record number of hits: 9,354. This broke the previous record of 6780 (set on October 22) and not just by a little bit. Unfortunately due to a computer problem, we don’t have a count for the first 10 days of October, but I’m sure that we were over 150,000 hits in October. Some of these are robot hits and we get more robot hits than we used to.
TCO has inquired about whether there is a legitimate purpose for using off-center PCs. I can’t think of any valid purpose. Here’s a good reason why not from our E&E article, where we showed how the MBH algorithm turned series upside down if it improved the hockey stick fit. Here’s how we wrote it up. Continue reading →
Here is some interesting information from an Oman speleothem is a proxy for Indian Ocean monsoon levels. One of the most influential proxies in Moberg [2005] is Oman coldwater diatoms and there is a connection. It may also shed some light on Himalaya ice cores, which also measure dO18 in monsoone precitation. Continue reading →
Climate Audit 
Op Eds at Pielke
Roger Pielke requested op ed’s from Mann and myself as to why anyone should care about the hockey stick. Mann refused to participate. I wrote one, Ross drafted a version. Because I’ve been travelling, I didn’t have time to try to reconcile our views, so we each send in versions which can be read Ross here and me here. (archive) Kevin Vranes has written his own commentary.
There have been a few comments from realclimate coauthors (William Connolley and Rasmus) in the comments, which are worth reading through and both Ross and I have posted up supplementary comments as well.