As a spin-off from looking at Mann of Oak proxies, I did (what I regard) as a pretty bit of decoding of some measurement data in the Climategate documents.

The Climategate directory documents/briffa-treering-external/stepan/ contains a large number of tree ring measurement files dated July 1996 (with the characteristic suffix .rwl) with 3-character labels,

“ala” “all” “and” “ary” “aya” “bat” …

Interesting as the data might be, it’s hard to do much with it without a lexicon providing locations – and there isn’t such a lexicon in the briffa-treering-external files.

I browsed through the MBH98 proxy rosters when I was looking for oak chronologies, which reminded me that MBH98 had used a network of 61 Vaganov chronologies. No measurement data was available. I’d downloaded Vaganov chronologies from Mann’s University of Virginia website in November 1993 when it was temporarily online. (Shortly afterwards, Mann told Jones in a Climategate email that Scott[Rutherford] had messed up “big-time” in what he had left on the FTP site.)

I remembered that there had been a file in the MBH98 FTP site that had contained lat-longs for the Vaganov network, which had also had 3-character IDs. (The file is once again available in the Climategate documents – look for TREE/VAGABOV/ORIG/sib.dat in mbh98-osborn.zip.) The file sib.dat had 61 entries. They proved to be a perfect match to the *.rwl files at documents/briffa-treering-external/stepan/ .

This little bit of detective work yielded previously unavailable measurement data for MBH98 (measurement data that Mann might not have had access to.)

Of particular interest to me were the data sets in the Yamal area:

V1 V2 V3 V4

1 26 SOB 65.46 66.48

2 27 SOP 65.46 66.48

3 1 SCH 69.17 66.49

4 2 KHA 69.50 67.12

5 3 KHD 69.54 67.07

6 4 JAH 70.58 67.25

7 5 NID 71.40 66.13

…

Here there is a little additional information from an email in the Climategate documents (documents/briffa-treering-external/ecat/yam9610/ymiss.dat) dated Dec 10, 1996 which stated:

1. As regards individual ring width data of living trees from

Yamal we would remind you that you have them. Stepan gave to you

in England one diskette. There are data for Larix sibirica from

three sites (KHA – from Khadyta river, 67 12’N 69 50’E; JAH –

from Yahody river 67 07’N 69 54’E and POR – from Portsa river

67 27’N 71 00’E) and for Picea obovata from two points (SCH –

Shtshutshya river 66 49’N 69 50’E and KHD – from Khadyta river

67 07’N 69 54’E).

Many CA readers will recall Khadyta River as the Schweingruber site that occasioned considerable controversy in October 2009 just before Climategate (the Oxburgh “report” included Briffa’s online response in its bibliography, but did not discuss any particulars.) The JAH and POR sites were also discussed at the time. (Note that the YAD site – the one with the Dos Equis tree – is not mentioned in the above email.)

The Vaganov version of Khadyta River larch (KHA) included some (but not all) of the Schweingruber cores – the cores that Gavin Schmidt had accused me of finding randomly on the internet.

I did a quick RCS-emulation on the four Yamal measurement data sets in the Vagnov network, shown below. The first three Yamal data sets (kha, khd, sch – one larch and two spruce) have very pronounced divergence problems and all have late 20th century values below the average of the last few centuries. (Even though JAH has an upward trend over the past few centuries and closes above the average of the last few centuries, it also has a divergence problem with the last half 20th being somewhat lower than first half 20th.)



Figure 1. Four Yamal Chronologies from Climategate Documents

CA readers may also recall that, unlike the above chronologies, Briffa’s Yamal chronology has a pronounced HS shape. The figure below show Yamal as it contributes to Kaufman et al 2009 – where it closes at a remarkable 6 sigma. Another accessible version is in the AR4 spaghetti graph that Overpeck (a Kaufman coauthor) included as part of his efforts to deal a “mortal blow” to the myth of an MWP.

The difference between the decline observed in the large-population Schweingruber network and the opposite behavior in Briffa’s Yamal chronology has always been a big problem for me. If most (or even a number of) chronologies in the area decline, then any competent analyst would inquire into the reliability of a chronology showing opposite behavior.

It’s very disappointing that David Hand didn’t assess the problem. It would really be much healthier if inquiries actually inquired into the problems that are at issue.



