Written by S. Fred Singer, President, Science and Environmental Policy Project
By A.W. Montford. Stacey International. London. 2010. 482pp.
Andrew Montford, a Scot, blogs under the name of Bishop Hill. I have not met him personally, but in correspondence with him I generally address him as Your Grace a bit of humor.
This is probably the best book about the Hockey Stick. And while some of the detail may be overwhelming to the innocent reader, it does present all of the relevant facts as far as I can tell.
You will not only become an expert on tree rings, and get to know trees by their "first name," so to speak, but you will also get to learn about difficult statistical concepts, such as "principal component analysis." PCA is an important statistical technique and one which the originator of the Hockey Stick, Professor Michael Mann, apparently failed to fully grasp.
There is little one can add to Montford's comprehensive account, so I will just supply some personal details. My own involvement in the hockey-stick affair is of no real consequence -- and certainly not as important as that of the Canadians, Steven McIntyre and Ross McKitrick. They are the ones who "broke the Hockey Stick," and Professor Edward Wegman of George Mason University, an expert statistician, provided the finishing touches.
I first learned of the Hockey Stick by reading the original paper by Mann, Bradley, and Hughes in Nature in 1998 and was surprised that it showed an extended decline of global (or NH) temperatures since the year 1000AD, until a sudden and major warming in the 20th century (the "blade" of the Hockey Stick). But providing some reassurance, there seemed to be good overlap between 1900 and 1980 with the instrumental record of Phil Jones, which showed a continuing rise in temperature from 1980 to the end of the century.
I had no basis to question the MBH work, but I noticed that the proxy record suddenly stopped in 1980 and did not extend beyond.
At that time, I was heavily influenced by the satellite data of Christy and Spencer that showed no atmospheric warming trend from 1979 to 1997 -- in contrast to Jones' surface data from weather stations. Since Mann was using the Jones temperature data for calibration of the proxy record, I asked Mann if he had any post-1980 proxies. He replied rather brusquely that there were no suitable data available. This was my only exchange with Mann, and I've preserved those emails.
Of course, I did not believe Mann, since I knew of tree ring data (by Jacoby in 1996) that showed no temperature rise since 1940 (see figure 16 in my 1997 book Hot Talk Cold Science). I also knew that Dahl-Jensen's ice cores showed no temperature rise since 1940. Hence I had doubts about the Jones dataand still do.
Following this unsatisfactory e-mail exchange with Mann, I had correspondence with McIntyre, Charles Keller, and others, trying to collect some post-1980 proxies to decide whether the Jones record was sound -- and whether Mann had stopped his proxy record in 1980 because it did not agree with Jones. Today we know, thanks to Climategate, that this might have been "Mann's Nature trick" in order to "hide the decline [of temperature]."
I visited Ed Cook at the Lamont Geophysical Laboratory to get post-1980 tree ring data, but was unsuccessful and finally gave up and turned to other matters. I also had a chance to speak briefly to Mann at the University of Virginia in Charlottesville, but could not extract any information from him. By then, he clearly regarded me as an 'enemy' and would not have given me anything of value.
My next encounter with the Hockey Stick was to review the IPCC's 3rd Assessment draft report in 2000. In the draft, the Hockey Stick was represented along with the Jones instrumental record, using colors of black and blue. I prevailed on IPCC to use colors that were easily distinguishable and was glad to see the Jones record appearing in red in the final IPCC version.
My next encounter came in 2003 when the editor of Energy & Environment sent me the first of the McIntyre and McKitrick papers for review. I was surprised to learn of some half dozen or so cases where Mann had clearly mishandled the data, even substituting imaginary sequences to fill gaps where data were not available. Of course, I endorsed publication of this first of the M&M attacks on the Hockey Stick.
I also witnessed the encounter between Mann and McIntyre at the hearings arraigned by the National Academy (NAS), charged to write a report on the Hockey Stick. Tellingly, Mann presented a brief account of his work and then immediately walked out without taking any questions or listening to the McIntyre presentation.
It was a thoroughly disappointing performance, particularly since some have misinterpreted the NAS report as an endorsement of the Hockey Stick. Actually, it was just the opposite, but it was misleading. The NAS stated that the 20th century was the warmest in the last 400 years, without making it clear that 400 years ago the earth was in the depth of the Little Ice Age.
It is certainly noteworthy that the IPCC in its fourth assessment report  no longer displays the Hockey Stick. It had been demolished by able statisticians like Wegman and von Storch. M&M had shown in the meantime that random numbers fed into the Mann algorithm would always produce a hockey-stick-shaped result.
The "Last Hurrah" for the Hockey Stick came in 2009 in a report by the United Nations Environment Program. Apparently, UNEP wanted to dramatize matters before the crucial Dec 2009 Copenhagen meeting and brought back the Hockey Stick in an inexpertly written report on climate change. They called it an "update" of the IPCC, but I'm sure that responsible IPCC scientists would not have agreed with that characterization. When we inquired where their Hockey Stick graph originated, we were led to a Norwegian biologist who had republished a graph he had found in Wikipedia - too funny for words! UNEP immediately reissued their report and replaced their Hockey Stick graph with a less controversial one.
There is a serious matter, however, which bears discussion: Did Mann commit fraud? I would give him the benefit of the doubt and suggest that his initial Nature publication contained many errors, including major statistical ones, which he might not have been aware of. But certainly, after these errors had been pointed out to him in no uncertain terms, how could he maintain his original posture and claim that the Hockey Stick truly represented the global temperature record of the last 1000 years?
All this in spite of many publications, both before and after 1998, that clearly told a different story: The compilation of temperature values by Soon and Baliunas, who were viciously attacked by the IPCC crowd; the isotope data of Cuffey; the global proxy data (omitting tree rings) of Loehle, which clearly showed the medieval warm period to be warmer than today; the deep-sea sediment record of Kegwin; and, of course, the historical record.
The Attorney General of the Commonwealth of Virginia, Kenneth Cuccinelli, is currently engaged in extracting from the University of Virginia (where Mann was a faculty member from 1999 to 2005) the e-mail records and other material relating to Mann. The University is fighting this demand in court yet it had already agreed some months ago to deliver the e-mail records of Patrick Michaels to Greenpeace! At that time, no cries of "academic freedom" were raised by the usual suspects. The silence then, and vociferous objections now expose the hypocrisy of the UVa Faculty Senate, the AAUP, the AAAS, and the Union of Concerned Scientists.
It is quite likely that Cuccinelli will discover a "smoking gun." Perhaps some of the emails that Phil Jones admitted to having deleted might tell us just when Mann became himself aware that the Hockey Stick was bogus and a fraud. - -