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Wanted to include this EXCERPT....Steve pursued this deception for a decade:

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A strange lack of twentieth century data

When McIntyre started to look at the numbers it was clear that there were going to be the usual problems with a lack of metadata, but there was more than just this. In typical climate science fashion, just scratching at the surface of the Briffa archive raised as many questions as it answered. Why did Briffa only have half the number of cores covering the Medieval Warm Period that the Russian had reported? And why were there so few cores in Briffa's twentieth century? By 1988 there were only 12 cores used, an amazingly small number in what should have been the part of the record when it was easiest to obtain data. By 1990 the count was only ten, dropping still further to just five in 1995. Without an explanation of how the selection of this sample of the available data had been performed, the suspicion of `cherrypicking' would linger over the study, particularly since the sharp twentieth century uptick in the series was almost entirely due to a single tree (It is true to say, however, that Hantemirov also had very few cores in the equivalent period, so it is possible that this selection had been due to the Russian and not Briffa).

The lack of twentieth century data was still more remarkable when the Yamal chronology was compared to the Polar Urals series, to which it was now apparently preferred. The ten or twelve cores used in Yamal was around half the number available at Polar Urals, which should presumably therefore have been considered the more reliable. Why then had climatologists almost all preferred to use Yamal? Could it be because it had a hockey stick shape?

Another juicy segment:

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The Khatdyta River experiment

But there was another mystery in Briffa's paper too. As we have seen, Briffa had been in the business of creating regional chronologies, for example supplementing Taimyr with data from other locations such as Avam and Balschaya Kamenka. Similar regional chronologies had been created for Fennoscandia and allegedly for Yamal. But the Yamal data appeared to represent only the original Hantemirov and Shiyatov data with no supplementation with other sites in the area at all. Why had Briffa left Yamal on its own, when the core count was so low? Suitable data was certainly available - Schweingruber had collected samples at a site called Khadyta River, close to Yamal, and with 34 cores recorded it represented a much more reliable basis for reconstructing temperatures.

McIntyre decided to perform a sensitivity test on Briffa's database, replacing the 12 cores that were behind the twentieth century uptick in the Yamal series with the 34 from Khadtya River. The revised chronology was simply staggering. The sharp uptick in the series at the end of the twentieth century had vanished, leaving a twentieth century apparently without a significant trend. The blade of the Yamal hockey stick, used in so many of those temperature reconstructions that the IPCC said validated Michael Mann's work, was gone.

Sound and fury

The reaction to McIntyre's blog posts on Yamal was almost instantaneous. The RealClimate blog, run by prominent climate scientists in an effort to protect the IPCC orthodoxy, ridiculed McIntyre's work:

McIntyre has based his ‘critique’ on a test conducted by randomly adding in one set of data from another location in Yamal that he found on the internet. People have written theses about how to construct tree ring chronologies in order to avoid end-member effects and preserve as much of the climate signal as possible. Curiously no-one has ever suggested simply grabbing one set of data, deleting the trees you have a political objection to and replacing them with another set that you found lying around on the web.

A few weeks later, Briffa and some of his colleagues joined in, writing a long response to McIntyre. Interestingly, this took a slightly different line to their colleagues at RealClimate, acknowledging that Khadtya River met the criteria for inclusion in the the Yamal chronology, but claiming somewhat implausibly that they had not considered it at the time.