One of the main Hockey Team studies is Esper et al 2002, which is published in Science and, naturally, no data is archived. Esper has not deigned to reply to any emails by me requesting data. Esper and coauthors have just published an article in QSR leading with a discussion of the Mann controversy. I’m told that Esper could not even bring himself to mention my name in connection with this and therefore cited Regalado  (the Wall Street Journal article) – no doubt surprising the reporter. Actually it’s rather ironic that ES&T trashed the Wall Street Journal for this article – can you think of any other newspaper article in recent memory which has been cited in a serious academic journal and by Esper no less.
Esper does not do archiving; so it’s hard to get much traction on Esper et al . However, I recently read an article at his website discussing RCS on the Gotland site (mentioned in Esper et al 2002). So I’ve got a bit of a foothold.
Esper has posted up Esper J, Cook ER, Krusic PJ, Peters K, Schweingruber FH (2003) Tests of the RCS method for preserving low-frequency variability in long tree-ring chronologies. Tree-Ring Research 59, 81-98. This contains a detailed discussion of the RCS method on the Gotland site. Esper himself doesn’t do archiving of data, but, in this case, the site can be shown to be swed022, which was archived at WDCP.
The graph below shows (top): ring width and bottom – maximum density. A mere civilian looking at the top panel would not be able to deduce that 20th century ring widths are exceptionally wide. But the Hockey Team has ways of extracting unique 20th Century warmth even from a tough-looking data set like this. We’ll see how they do it (though not today)
Figure 1. From Esper et al 2003.
For now, I’ve contented myself with proving that swed022w and swed022x were the same data sets as Esper used (since he wouldn’t do anything as banal as giving a data citation.) The figure below shows that the data sets are the same.
Figure 2. Replication of Esper figure using swed022w and swed022x.
Just for fun, I’ve included a couple of diagrams that I’ve used from time to time (you’ll remember the one for Tasmania). Here’s a grass plot for Gotland.
Here’s the same data by age, rather than year.
Now that I’ve got a bit of a foothold, I’ll look at how Esper handles the Gotland site. There’s much of interest in the article.
Update- Sept. 13: I’ve deleted a sarcastic honorific.