Don't miss this article by Andrew Orlowski

Climategate: Why it matters  • The Register

Jones and his team began to produce work that contradicted the established picture in 1990 - and CRU was able to do so from both ends. By creating new temperature recreations, it could create a new account of history. By issuing a monthly gridded temperature set while making raw station data unavailable for inspection, it defined contemporary data. So CRU controlled two important narratives: the "then", and the "now".

In the FOIA.ZIP archive, we find Jones unambiguous in an email: "We will be rewriting people's perceived wisdom about the course of temperature change over the past millennium," he wrote.
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'Climategate' raises far more questions than it answers, and one of the most intriguing of these is how a small group (backing a new theory, in an infant field) came to have such a huge effect on global policy making.