Boulton’s Hockey Team associate, Gabi Hegerl, archived the proxy versions used in Hegerl et al 2007 in February 2010 – see here ftp://ftp.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/hegerl2007/nh-temp-hegerl2007.txt . I’ve discussed this reconstruction in earlier CA posts. Boulton used Hegerl’s Hockey Stick in the Royal Society of Edinburgh submission on Copenhagen.

I’ve had the proxy versions for a couple of years. I originally requested this data in September 2005 in my capacity as an IPCC peer reader – IPCC WG1 Chairman threatened to expel me as a peer reviewer for the temerity of asking for unarchived data for an unpublished study. However with some persistence, Hegerl emailed me the data in 2007.

The reconstruction versions were archived a few months ago in September 2009, but this is the first that I’ve seen this file. Previous archived versions only went back to 1251. There are new digital files (referred to in Hegerl et al 2007, but previously unarchived) that go back to 946 and 558.

In Boulton’s Copenhagen paper, he says:

Several independent estimations have now been made of the global or hemispheric average temperatures for the last two millennia. Figure 3 is one of these [Hegerl], and shows that the late 20th Century warming has been rapid and large compared with earlier periods (note that this is independent of the University of East Anglia reconstruction, about which there has recently been much controversy).

Boulton is, of course, totally wrong that this is “independent of the University of East Anglia reconstruction, about which there has recently been much controversy”.

The longest reconstruction illustrated in Boulton’s Figure 3 is a composite of 5 series: Mann’s PC1 (falsely identified by Boulton associates Hegerl and Crowley as “an RCS processed tree-ring composite used in Mann et al. (1999)” – it is provably the PC1; Briffa’s Tornetrask series used in MBH and Jones et al 1998; a Greenland O18 record used in MBH99 and in Jones et al 1998; Briffa’s Taymir series; and the Yang composite (heavily influenced by Thompson’s Dunde series). Later, Briffa’s Yamal is added in (mixed with some other series that Crowley has failed to identify for a number of years now). Jacoby’s Mongolia and some strip-bark foxtails.

The Hegerl reconstruction is not “independent” of the University of East Anglia reconstruction (whatever that supposedly means).

Perhaps Boulton’s associates decided to cooper up their archiving now that Boulton is participating in the Jones inquiry, perhaps it’s just coincidence. In either case, it’s welcome. Maybe in another couple of years, we’ll find out what’s in the west Siberian series.



