UPDATE: The Climate Audit server is getting hit with heavy traffic and is slow. If anyone has referenced graphs in blog posts or news articles lease see the mirrored URL list for the graphs at the end of this article and please consider replacement in your posting. I’ve also got a mirrored article of the Climate Audit post from Steve McIntyre.  -Anthony

UPDATE2: Related articles

Update: A zoomed look at the broken hockey stick

A look at treemometers and tree ring growth

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We’ve always suspected that Mann’s tree ring proxies aren’t all they are cracked up to be. The graph below is stunning in it’s message and I’m pleased to present it to WUWT readers. I’m sure the Team is already working up ways to say “it doesn’t matter”.

The QOTW this week centers around this graph:

The quote of the week is:

I hardly know where to begin in terms of commentary on this difference.

- Steve McIntyre, Climate Audit in Yamal: A “Divergence” Problem

The graph above shows what happens to the “Hockey Stick” after additional tree ring data, recently released (after a long and protracted fight over data access) is added to the analysis of Hadley’s archived tree ring data in Yamal, Russia.

All of the sudden, it isn’t the “hottest period in 2000 years” anymore.

Steve writes:

The next graphic compares the RCS chronologies from the two slightly different data sets: red – the RCS chronology calculated from the CRU archive (with the 12 picked cores); black – the RCS chronology calculated using the Schweingruber Yamal sample of living trees instead of the 12 picked trees used in the CRU archive. The difference is breathtaking.

I’ll say. Ding Dong the stick is dead.

This comparison to CRU archive data illustrates the most extreme example of scientific cherry-picking ever seen. As Steve writes in comments at CA:

Also keep in mind the implausibly small size of the current portion of the Yamal archive. It would be one thing if they had only sampled 10 trees and this is what they got. But they selected 10 trees out of a larger population. Because the selection yields such different results from a nearby population sample, there is a compelling prima facie argument that they’ve made biased picks. This is rebuttable. I would welcome hearing the argument on the other side. I’ve notified one dendro of the issue and requested him to assist in the interpretation of the new data (but am not very hopeful that he will speak up.)

See the complete report on this new development in the sordid story of tree ring proxies used for climate interpretation at Climate Audit. And while you are there, please give Steve a hit on the tip jar. With this revelation, he’s earned it.

The next time somebody tells you that tree rings prove we are living in the “hottest period in 2000 years” show them this graph and point them to this Climate Audit article.

Watts Up With That?