Jones and Mann #2: New WDCP Archive

There is a new (December 2004) archive for Jones and Mann [2004] at WDCP here. Jones (pers. comm., July 2004) had previously sent me another version of this data. Here are some comments to save others some time in considering this archive.

The README at the WDCP archive states:

Data for the series used in Figures 2, 4-7 and 8 are mostly available. Some series are missing as we have been asked not to make these freely available. For these, you will have to contact the appropriate author(s).

Figure 4 of Jones and Mann [2004] shows 24 proxy series. However, the archive contains only 15 of the 24 series shown in Figure 4. Not archived are 6 tropical series from Lonnie Thompson, 2 series from Wang and one Antarctic series from van Ommen. In response to an earlier complaint to Climatic Change, Thompson has archived data for these 6 series here. I have confirmed that the Thompson versions are identical to the Jones versions, where they overlap (although the Dunde series at the Thompson archive is inconsistent with previous grey versions used by Mann and Yang, as discussed in an earlier post.)

In the email version of this data that was sent to me in July 2004, Jones had reversed the 3 Thompson Andean series with the 3 Thompson Himalayan series. This did not affect the plots in Figure 4, but I think that the decadal correlations in Table 1 of Jones and Mann [2004] were reversed (but I need to double-check this and will edit this post when I do so).

Although the README says that the archived data is “raw data”, it has actually been transformed with mean of 0 and sd of 1 on the period 1750-1950 (although in my calculations, the sd is only correct rounded to a couple of decimal places, which seems odd.) I’ve checked each of the 15 archives series against the Jones email version and they all match up to linear transformation.

I presently have digital versions of 23 of 24 series. I’ll try to remember to post up a script to collate this data in a few days.

Last year, I unsuccessfully tried to get the Lawdome data from Tas van Ommen. I just tried again. (One of the frustrating aspects of multiproxy studies is the tendency to use at least some unarchived data, so that it becomes impossible to replicate the results.)

One Comment

  1. TCO
    Posted Sep 10, 2005 at 7:45 PM | Permalink

    I think that the journal publishing these reconstructions (meta-analyses) should frown on the use of “grey data” and should check into this as an important part of the peer review. What is the norm in the social sciences? Are these sorts of things done in sociology meta-analyses?

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