Just a quick interjection to note that the Yamal story has reached Andrew Orlowski of “The Register” under the title “Treemometers: a new scientific scandal“. [Steve: John A posted up this thread. I do not endorse everything in the article linked here. I also link to realclimate from time to time without agreeing with it. […]
We’ve been discussing Briffa and Yamal at CA for a couple of years and many, if not most, regular readers understand the significance of the Yamal collapse. For example, as recently as Sept 19, we were observing the dependence of the Kaufman reconstruction on the Yamal series. So the long-sought fresh information on Yamal (and […]
The second image below is, in my opinion, one of the most disquieting images ever presented at Climate Audit. Two posts ago, I observed that the number of cores used in the most recent portion of the Yamal archive at CRU was implausibly low. There were only 10 cores in 1990 versus 65 cores in […]
A few days ago, I became aware that the long-sought Yamal measurement data url had materialized at Briffa’s website – after many years of effort on my part and nearly 10 years after its original use in Briffa (2000).
The archived information for Wilson et al 2007 contains interesting new information on an unpublished West Siberian series (Putorama, 70 31 N, 92 57E). In this case, I was actually able to obtain a better correlation to gridcell temperature than the one reported by Rob by using a gridcell closer to the actual location. This […]
Readers of this blog are familiar with the Yamal subsitution. Briefly, Briffa et al 1995 reported in Nature that 1032 was the coldest year of the millennium based on no more than 3 poorly dated and short cores in the 11th century. Subsequently new cores were dated to the 11th century by Schweingruber, resulting in […]
If you actually look at the medieval proxy index of the "other" studies (Briffa 2000, Crowley and Lowery 2000, Esper et al 2002, Moberg et al 2005), the medieval proxy index is usually just a razor’s edge less than modern proxy index – just enough that the study can proclaim with relief that the modern […]
Rob Wilson has written in sharply criticizing me (Yamal Substitution #3) for a lack of a balanced presentation on the Yamal substitution, and, in particular, for not acknowledging the "clear statistical reasons (related to variance changes through time)" that he had provided me offline for why D’Arrigo et al 2006 made the Yamal substitution. Also […]
There’s some very important new information related to the “Yamal Substitution” – which sounds like a Ludlum novel title – in the Esper site chronologies which Science provided today. Also see here here here. Here’s a plot of a 40-year smooth of the Esper site chronology for Polar Urals and Briffa’s archived version of the […]
I wrote recently about the Yamal substitution for the Polar Urals series in both Osborn and Briffa [2006] and D’Arrigo et al, 2006. This substitution is not incidental as the Yamal version had by far the strongest closing uptick in either data set, while the updated Polar Urals ring width series (1998 update) had elevated […]
Climate Audit 