Christopher Booker has a fantastic piece in the Telegraph today (HT Iain Dale) saying what statisticians like myself and scientists are increasingly pointing out – the globe ain’t warming quite like we thought it was:
The common view of the IPCC is that it consists of 2,500 of the world’s leading scientists who, after carefully weighing all the evidence, have arrived at a "consensus" that world temperatures are rising disastrously, and that the only plausible cause has been rising levels of CO2 and other man-made greenhouse gases.
In fact, as has become ever more apparent over the past 20 years -not least thanks to the evidence of a succession of scientists who have participated in the IPCC itself – the reality of this curious body could scarcely be more different.
It is not so much a scientific as a political organisation. Its brief has never been to look dispassionately at all the evidence for man-made global warming: it has always taken this as an accepted fact.
Indeed only a comparatively small part of its reports are concerned with the science of climate change at all. The greater part must start by accepting the official line, and are concerned only with assessing the impact of warming and what should be done about it.
But surely all the evidence shows that the earth’s temperature is rising at an alarming rate?
Initially the advocates of global warming had one huge problem. Evidence from all over the world indicated that the earth was hotter 1,000 years ago than it is today. This was so generally accepted that the first two IPCC reports included a graph, based on work by Sir John Houghton himself, showing that temperatures were higher in what is known as the Mediaeval Warming period than they were in the 1990s.
The trouble was that this blew a mighty hole in the thesis that warming was caused only by recent man-made CO2.
Then in 1999 an obscure young US physicist, Michael Mann, came up with a new graph like nothing seen before. Instead of the familiar rises and falls in temperature over the past 1,000 years, the line ran virtually flat, only curving up dramatically at the end in a hockey-stick shape to show recent decades as easily the hottest on record.
This was just what the IPCC wanted, The Mediaeval Warming had simply been wiped from the record. When its next report came along in 2001, Mann’s graph was given top billing, appearing right at the top of page one of the Summary for Policymakers and five more times in the report proper.
But then two Canadian computer analysts, Steve McIntyre and Ross McKitrick, got to work on how Mann had arrived at his graph.
When, with great difficulty, they eventually persuaded Mann to hand over his data, it turned out he had built into his programme an algorithm which would produce a hockey stick shape whatever data were fed into it. Even numbers from the phonebook would come out looking like a hockey stick.
So what has happened to global temperatures over the past decade?
By the time of its latest report, last year, the IPCC had an even greater problem. Far from continuing to rise in line with rising CO2, as its computer models predicted they should, global temperatures since the abnormally hot year of 1998 had flattened out at a lower level and were even falling – a trend confirmed by Nasa’s satellite readings over the past 18 months.
So pronounced has this been that even scientists supporting the warmist thesis now concede that, due to changes in ocean currents, we can expect a decade or more of "cooling", before the "underlying warming trend" reappears.
The point is that none of this was predicted by the computer models on which the IPCC relies. Among the ever-growing mountain of informed criticism of the IPCC’s methods, a detailed study by an Australian analyst John McLean (to find it, Google "Prejudiced authors, prejudiced findings") shows just how incestuously linked are most of the core group of academics whose models underpin everything the IPCC wishes us to believe about global warming.
Don’t get me wrong. It is very likely that the industrial revolution has contributed to recent temperature rises, and we are also facing a fossil-fuel energy crisis that makes transferring resources into renewable energy and nuclear energy a vital necessity. But it’s time that we all started critically examining the data available and asking ourselves whether we really are the prime cause of the nice hot summers we’ve had recently as so many people claim.