The last 8 years of our chronology ARE based on data from a decreasing number of sites and trees and this smaller available sample does emphasise the faster growing trees, so this section of the chronology should be used cautiously. The reworked chronology, based on all of the currently available data is similar to our previously published versions of the Yamal chronology demonstrating that our earlier work presents a defensible and reasonable indication of tree growth changes during the 20th century, and in the context of long-term changes reconstructed over the last two millennia in the vicinity of the larch treeline in southern Yamal.
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This does not mean that these chronologies will not change as additional data become available and as the RCS processing technique evolves, but the results we show here do suggest that McIntyre’s sensitivity analysis has little implication for those other proxy studies that make use of the published Yamal chronology data.
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When using the RCS technique, it is important to examine the robustness of RCS chronologies, involving the type of sensitivity testing that McIntyre has undertaken and that we have shown in this example.

IOW McIntyre, Jeff Id, et al are on the right track in scrutinizing RCS end-point issues when dealing with relatively small, heterogenous samples.
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And Tom P? Out to lunch. Trying to sweep under the rug the problems that Briffa here admits are non-trivial.
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The game continues.

The H & S 2002 reconstruction covers almost 4000 years. It may well be based on different data than was used in the work cited by Briffa that was done 4 years earlier.

So, when Briffa responds that his Yamal work is “based on” the data that “forms the basis of” the H & S 2002 analysis, maybe it’s really important to know what the meanings of based and basis are.

It’s tempting to presume that there is a lot of similarity between Briffa’s data set and the data used for the “one approach to constructing a mean chronology” using “224 individual series of subfossil larches” “supplemented by … 17 ring width series from 200-400 year old living larches.” (pg. 721, H&S 2002)

That “one approach” isn’t otherwise described in H&S 2002–not in the text nor in the figures.

Briffa’s data at CRU is similar in numbers of samples/series, but not in the number of cores from living larches. Briffa seems to have used fewer than 17.

Maybe I’ll live long enough for the details to be revealed that might clear up the discrepancy between the basis of H & S 2002 and the data Briffa’s Yamal work was based on. I hope so–I want to improve my golf game, and it clearly will also take a lot of time for me to end up on the correct side of 100.

from that paper -

“The more northerly tree-line suggests that the most favourable conditions during the last two millennia apparently occurred at around ad 500 and during the period 1200–1300. It is interesting to note that the current position of the tree-line in Yamal is south of the position it has attained during most of the last three and a half millennia, and it may well be that it has not yet shifted fully in response to the warming of the last century.”

nobody seems to have a comment on this. why? what am i missing

realise this thread is on tree-rings & Briffa papers, but to a layman like me if you use tree-ring data/dendro calcs in a study you also look at forest tree-line movements first & then look at the tree core data second to confirm/make robust your conclusions.