No matter whether we agree with the conclusions of climate scientists or not, this kind of thing should worry everyone:

The idea that there would be inconsistent versions of something from Lonnie Thompson is not something that will surprise previous readers. Here is a collation of different “grey” versions of one of the components in the above graphic (Dunde). Dunde was drilled in 1987 and is a staple of multiproxy studies. It has about 3000 samples containing not just dO18 values but relevant dust and chemistry information. Thompson has refused to archive original sample data. I’ve made many efforts to get this data but have been rebuffed by Thompson himself, the National Science Foundation, Science magazine and the National Academy of Sciences (both in their capacity as publishers of PNAS and in their capacity as organizers of the Surface Temperatures panel). This is important data which cannot be duplicated by third parties – Thompson has an obligation to archive all sample information and NSF and the journals have an obligation to require him to archive it: none of them are living up to these obligations. Maybe Al Gore could ask him.

The results of different Thompson versions of Dunde make a spaghetti graph all by themselves. Note that one version with annual data ends at a very low value. This inconsistency is not isolated to Dunde – as you can see from perusing the posts in the Thompson category.

Dunde Versions. Heavy black – Yao et al 2006 (3 year rolling average); thin black – MBH98 (annual); red – PNAS 2006 (5-year averages); blue – Clim Chg 2003 (10-year averages); purple – Yang et al 2002 (values in 50 -year intervals); green – Crowley and Lowery 2000 (original in standardized format, re-fitted here for display by regression fit to MBH98).

What you see is a climate scientist  who refuses to release a critical experimental / observational data set to the broader community, while at various times releasing what appear to be wildly different versions of the data.

And this is frightening as well:

In 2003, Thompson took a new ice core at Bona Churchill. We haven’t heard anything about it. On previous occasions, e.g. here , I’ve predicted that 20th century values at this site would be lower than 19th century values – using the mining promotion philosophy that if Thompson had had “good” results, we’d have heard about them. The prediction has a little more teeth than that as dO18 values at nearby Mount Logan obtained and already published by Fisher et al went down in the 20th century.

Here, we see that Steve McIntyre is able to make reliable predictions of a climate scientist’s actions using the simple prediction heuristic "if the study does not end up getting published, it means that the results did not support the catastrophic man-made global warming proposition."  Call it, I gues, the Inconvinient experimental results.

Oh, and by the way — Thomson was the source of many of the temperature reconstructions, including the "hockey stick," shown by Gore in An Inconvinient Truth.