Why sumo wrestlers cheat, why drug dealers are poor, the socioeconomic patterns of naming children - the book Freakonomics brought economic analysis to bear on unexpected and quirky issues and came up with unexpected and quirky answers. It's little surprise, then, that the 2005 book - by University of Chicago economist Steven Levitt and New York Times journalist Stephen Dubner - sold more than 3 million copies worldwide.

Numbers like that demand a sequel, and this month Levitt and Dubner delivered theirs: SuperFreakonomics: Global Cooling, Patriotic Prostitutes and Why Suicide Bombers Should Buy Life Insurance. But while their first book focused mostly on smaller stuff, SuperFreakonomics takes on one very big subject - global warming - and it has got environmentalists and climate scientists across the blogosphere feeling dismayed by the Freaky Ones.

What's the problem? For starters, Levitt and Dubner begin their chapter on climate change by citing the concerns over the risk of global cooling, which were held briefly by some scientists in the early 1970s - that's a common trope for climate contrarians, who say that if concerns over cooling turned out to be false, maybe the same thing will come of the current worries over global warming. They go on to question the accuracy of today's climate models, and by extension, whether we should really be concerned about potentially catastrophic temperature increases over the coming century. They further point out that plants may indeed thrive in a future with higher carbon dioxide levels - after all, greenhouses pump in extra CO 2 to encourage growth - but they fail to note that hotter summers and increasing droughts could threaten agriculture. They assert that sea levels can rise only 1.5 ft. over the coming century, ignoring the very real risk of accelerated melting of the Greenland and Antarctic ice sheets, which would multiply that number. They downplay the risks of carbon dioxide as a greenhouse gas. And they make a habit of referring to any climate scientist who expresses fear over a warmer future as a "doomsayer" - a bit of a loaded term.