It’s obviously been pulling teeth to get data from Esper. After only two years of trying, I’ve recently obtained all but one site chronology and 10 of 14 measurement sets; and gobbledy-gook about methodology. It’s a very Mannian process. While I continue to try to get the rest of the information, I thought that it would be interest just to do some simple plots and averaging of what I have. First, here is a spaghetti graph of the 13 site chronologies that have been sent so far (all smoothed), together with an unweighted average. The average inter-series correlation of the smoothed series is 0.10.
Figure 1. Spaghetti graph of Esper site chronologies (except Mongolia). Black- unweighted average.
You will notice that there are only two series out of the 13 which have strongly elevated closing values. Guess what they are? You should know already. They are both foxtails (interbreeding cousings of bristlecones) both from sites very close to Sheep Mountain, California. Even if you decided to permit bristlecone/foxtails as a proxy – questionable in terms of robustness – don’t you think that two out of 14 is overkill? Here are plots of the individual sites, again as delivered in February 2006:
Figure 2. Plots of 13 of 14 Individual Esper Site Chronologies
Now these series have not been re-centered or re-scaled. My impression is that Esper’s method does not involve re-centering or re-scaling at a site level. Indeed, my impression of Esper’s method is that site chronologies are not used – so while I appreciate getting these chronologies, I’m not entirely sure of how they were used by Esper (but soem of them were used by Osborn and Briffa after re-scaling.)
When you see these series, you really have to wonder what some of them are doing in a millennial chronology – what’s the point of the Zhaschiviersk segment, or, for that matter, the relatively short Tirol series?
Now take a look at these series and guess which ones were carried over into Osborn and Briffa?
1) an average of the two foxtail series (Boreal and Upperwright) except the earliest portion. (Osborn and Briffa also use Mann’s PC1, which is realy just the Sheep Mountain bristlecone in this period – so they also have 2 bristlecone/foxtail series out of 14, although the method of getting them is a little different.
2) the Ath(abska) series under the name Alberta or Jasper, in a different version with a lower MWP;
3) Taymir in a very slightly different version;
4) Tornetrask in a considerably different version with more HS;
5) Mangazeja is used in the same version;
6) Quebec (Bonif) is used in the same version;
7) Mongolia is carried over – probably in the same version, but I don’t have the Esper version;
8) Tirol is carried over in the same version, but the provenance in Osborn and Briffa (germ21) is wrong;
9) Campbell Dolomite/Mackenize Mts; Gotland; Jaemtland; Zhaschieviersk are not used in Osborn and Briffa.
10) the updated Polar Urals series shown here with a strong MWP is discarded in favor of Yamal. (The earlier Briffa version of Polar Urals had a very cold 11th century – Briffa said that 1032 was the coldest year of the millennium.) See posts on Yamal from Jan-February.