Climate Depot's tabloid style was captured in a headline earlier this week: "The Jig is Up! Climategate U-turn as Phil Jones admits: There has been no global warming since 1995." The spin applied to the story, about a media interview with the former director of the CRU, was picked up by news outlets and columnists around the world. But it distorted Prof. Jones's comments, which actually indicated that a short-term warming trend appears to exist at levels "quite close" to scientifically significant. And Prof. Jones stressed that statistically significant trends are much more likely to be detected over longer periods. "The fact that there is almost 95 per cent certainty about the rise from 1995 to 2009 means that it is likely," he said.
In keeping with his background as a weatherman, Mr. Watts's website focuses on the nitty-gritty of measuring temperatures. As one of the signature issues of his blog, Mr. Watts has focused on meteorological stations, arguing that they were often misplaced - positioned in areas where temperatures were artificially high, such as asphalt parking lots. The National Oceanic and Atmospheric Administration responded to this critique by calculating temperatures minus Mr. Watts's list of objectionable stations. Ironically, the new data showed a slight rise in temperatures.
As distinct from Mr. Morano's conservative populism and Mr. Watts's focus on the weather, Mr. McIntyre's Climate Audit is the most highbrow of the climate skeptic blogs. Even Mr. Mooney acknowledges that Mr. McInytre is "more scientifically inclined" than his peers. Climate Audit is regarded by many as the best of all the climate-skeptic blogs, the one richest in detailed technical arguments and most attentive to the rules of science and evidence.
To his many fans, Mr. McIntyre is a sterling example of a citizen-scientist, an amateur who was able to poke holes in a too-quickly constructed consensus. But to his critics, who include some of the most eminent names in climate science, he casts a very different image, as a gifted pest whose scattershot criticisms indiscriminately mix a few valid points with a larger body of half-truths, a potent concoction that produces much confusion but little benefit.
After working for years in the mining industry, Mr. McIntyre, 62, came to the climate-science debate in 2002 when he became suspicious of the political passions surrounding the Kyoto Protocol. He quickly teamed up with University of Guelph economist Ross McKitrick, who shared the businessman's doubts over the hockey stick graph, which became emblematic of the global-warming argument.
Their 2005 critique of the graph, published in Geophysical Research Letters, sparked a renewed examination of the hockey-stick data, but didn't make any fundamental change in the debate. Since its original publication, the graph research has been replicated by nearly a dozen studies. Although the hockey stick has been battered and bruised by many critics, it still works.
"What McIntyre has essentially done is put his finger on small technicalities that don't matter," argues Prof. Mann, now based at Pennsylvania State University. "In every case, they've been dismissed. When the question arises, does it make a difference? The answer is always no. All that is important to him is to be able to say that he's found a problem and then allow everybody else to say this fundamentally undermines the science."
The key objection to the work of bloggers such as Mr. McIntyre is that they are engaged in an epic game of nitpicking: zeroing in on minor technical issues while ignoring the massive and converging lines of evidence that are coming in from many disciplines. To read their online work is to enter a dank, claustrophobic universe where obsessive personalities talk endlessly about small building blocks - Yamal Peninsula trees, bristlecones, weather stations - the removal of which will somehow topple the entire edifice of climate science. Lost in the blogging world is any sense of proportion, or the idea that science is built on cumulative work in many fields, the scientists say.