Peer Review System Fails to Convince on
Climate Change when the Reviewers
are of Like Mind
20th February 2007
(Para in square brackets omitted by Ed)
Dr Fraser, a CSIRO chief research scientist, claimed (Business, 5/2) that peer reviewing of scientific analysis of climate changes supported the conclusion of the latest report of the International Panel on Climate Change that it is over 90 per cent certain that global warming is due to human activity. Whether such a conclusion is justified is being questioned by an increasing number of scientists and others, the latest being the major critique of the IPCC report published by the Fraser Institute in Canada (which follows a letter to the Canadian Prime Minister in similar vein by 61 prominent scientists). Moreover, as pointed out in a wide-ranging major critique of the Stern Review published recently in World Economics ( <http://www.world-economics-journal.com/> www.world-economics-journal.com) by highly qualified scientists and economists, a peer review system provides no assurance when the reviewers are of similar mind, as appears to be the case with both the Stern Review and the latest IPCC report (which is only a 20 page so-called Summary for Policy Makers Ð we have to wait for the actual scientific report).
Dr Fraser also suggested that the best climate models available today have incorporated all the various influences on warming and show that most of the warming since 1950 has been caused by greenhouse gases. But, even leaving aside the absence of warming between 1940 and 1965 when emissions grew rapidly, this seems na•ve. As I well know from my experience with economic models, the outcomes provided from modelling are only as good as the weightings given by the modellers to the various possible influences. This latest IPCC Summary report, for example, does not refer to the hockey stick analysis, given considerable weight in the 2001 IPCC report on the basis that it purported to show nine centuries of near constant temperatures, followed by a dramatic rise in the twentieth century. Why? Presumably because two recent US expert reports have shown the analysis in the hockey stick model to be invalid. So much for peer reviews, let alone scientific consensus.
[Serious questions must also be raised as to the value of a Summary report that purports to make a best estimate (?attempted consensus) of likely temperature increases of between 1.4 and 4 degrees over this century, apparently derived from over 20 such greenhouse climate models that produced temperature predictions ranging from 1.4 to 11.5 degrees. Even assuming the underlying analysis is correct, how can policy makers tell which of these models is correct and what action should be taken? There would, of course, be a vast difference between policies needed to deal with a supposed 1.4 degree warming and one of, say, 6 degrees. In short, the range of possibilities provided by even the consensus scientists seems of limited value].