http://www.cru.uea.ac.uk/cru/people/briffa/yamal2009/

As someone else mentioned there was a RealClimate post here:

http://www.realclimate.org/index.php/archives/2009/09/hey-ya-mal/

These people obviously don’t like each other. This does not concern me or probably most people who just want to know what Earth’s climate is likely to do in the future and how this might effect us.

The bulk of your submission, paragraphs 3 to 18, concerns your issues with the creation and selection of individual proxies. Paragraph 19 concludes your analysis with showing in fig. 5 an example of how such issues might affect a reconstruction (Briffa 2000) that was used in both the third and fourth IPCC reports.

Until you establish the basis for both of your plots in figure 5, it would be difficult to quantify what might be the contribution to a final reconstruction from any of your issues with the individual chronologies.

Given that your submission is currently part of the material being rapidly assessed by the Select Committee for their final report, and that you now will not be able to check how these plots were derived for a “week or so”, it might be worth immediately advising the committee of these uncertainties in your submission.

Steve As I said before, I’ll doublecheck on the point in question. I like to be precise about calculations and have undertaken to post up scripts. For the point in question, it doesn’t matter whether the variation is Polar Utals/Yamal alone or whether it is Polar Urals/Yamal and Tornetrask. In either case, the result is sensitive to minor variations in version. Obviously the obligation to have reported this rested with Briffa and CRU and they should have reported it long ago. Again, I have personal business this week that interferes with me posting the scripts up as promptly as I would like.

There appears to be another issue with your submission. Your version in fig. 5 of what is claimed to be a reproduction of the published Briffa (2000) plot of changes in the northern high-latitude temperature is significantly different from the original. Here is your plot overlain with a displaced version of the original:

img13.imageshack.us/img13/5213/briffavsmcibriffa.png

Some of the discrepancies between the plots may be partly down to a different choice in smoothing function. Notably, though, the original does not show the marked difference seen in your version between the medieval warm period and the twentieth century. In fact you cut off your plot before the peak temperatures of the late tenth century seen in the original. The blue line shows that any difference between these two periods in the original is not readily discernible, unlike in your attempted replot. This makes the contrast with your second reconstruction which replaces one, or maybe two, of the chronologies rather less marked.

I think it would be best to first calculate a more accurate reproduction of the Briffa reconstruction including all of the relevant periods before commenting on any differences with your version.

Steve: I’ll take a look at this in a week or so. I have some personal things that are taking quite a bit time over and above Climategate. My Briffa starting point is drawn from Briffa’s digital data.

Steve: “I’ve told Tom P that I’m very busy right now and can’t provide room service for him. In an incident last fall, he got hugely annoyed when room service didn’t attend to him within several hours of his request and went to realclimate to complain, where he was proclaimed as Gavin’s Guru.”

I’ll respond here, as people really do seem to be getting very agitated over on that thread, whether my comments are snipped, or even if I just redirect their questions to a different thread.

As you should remember last September I said I was “impatient” to see the analysis of combining the Khadtyta and Yamal series, and so ran the R code myself. You may think I was “hugely annoyed” but I can assure you I was not – you provided a good impetus for me to look at the scripts myself. Also, I think you, not RealClimate, should take credit for giving me any “guru” status, however kindly your intent!

As to checking quite what you did to produce figure 5 of your submission, I’m not sure the Select Committee would see this as a question of providing “room service”. Normally one establishes the basis of a plot before drawing any conclusions and certainly prior to publication, not after. I presume you will be clarifying this issue for the Committee in good time for any deliberations they might make based on your submission.

Steve: the first wasn’t really a submission but a suggestion for an amendment to their questions – which showed a confusion between instrumental temperature data and proxy reconstructions, two different CRU topics. Unfortunately, they did not respond to this and the entire hearing was marred by confusion between these two different topics.

I’m surprised you weren’t snipped by the moderators given you chose to pose a question about dendrochronology in general and Yamal in particular on a thread specifically about Steve’s submission to the Select Committee. Are you trying to hijack this thread?

There seems to be a rather inconsistent applications of standards by the moderators on this site. You may have noticed it often seems to be based on who is commenting rather than the content of the comment.

Steve: Tom P and Ken, there are many Yamal threads that are excellent locations for discussions of Yamal.

http://www.publications.parliament.uk/pa/cm200910/cmselect/cmsctech/memo/climatedata/contents.htm

Some familiar names included.