Infamous 'Hockey Stick' Graph Under Fire

US Congressional inquiries on 'hockey stick' graph claim it is fundamentally flawed, writes Christopher Booker. 

By Christopher Booker
Published: 5:05PM 12 Sep 2009

A number of readers wrote in to express surprise at the recent letter from the US scientist Dr Michael Mann claiming that his famous "hockey stick" graph, showing temperatures having suddenly soared at the end of the 20th century to unprecedented levels, had been endorsed by the US National Academy of Sciences. Neither of the two Congressional inquiries involving the NAS did anything of the kind. Both found that the computer model used to create Dr Mann's "hockey stick", completely rewriting climate history, was fundamentally flawed.

This is one reason why, despite all the efforts made to defend Dr Mann's graph by his academic colleagues (describing themselves as the Hockey Team), I have described it as "one of the most comprehensively discredited artefacts in the history of science".

Now the Hockey Team have done it again. As part of the general drive to hype up panic over global warming in the run-up to December's Copenhagen conference, several of them are among the authors of a paper, published in the September 4 issue of the US journal Science, which claims to rewrite the climate history of the Arctic. As in the original version, the new hockey stick-shaped graph produced by their computer model shows temperatures gently declining for 900 years, then suddenly shooting up in recent years to record levels.

As usual, there are several odd features of their model, which is largely based on data from Professor Philip Jones's Climate Research Unit in Norwich – the data he refuses to publish because it is a state secret. But perhaps the oddest aspect of all is the contrast between this new study and the comprehensive record of Arctic temperatures compiled by the Danish Meteorological Institute from 1959 to the present day.

Anthony Watts's Watts Up With That blog (see the blog posting on September 4) created an animated graphic showing the DMI's temperature changes over the past 50 years. Far from confirming the hypothetical upward spurt claimed by the Hockey Team's computer, the most remarkable feature of the actual record is that it shows no significant change whatever.
The unshakeable faith in computer models shown by the scientists who programme them would be the envy of any religious sect in the world.

http://www.telegraph.co.uk/comment/columnists/christopherbooker/6179713/New-hockey-stick-graph-