Tuesday, August 28, 2007

Global Warming?

Very nicely put.

Denier's Confession
Global warming is more alarmist than alarming.
Tuesday, August 28, 2007 12:01 a.m. EDT

The recent discovery by a retired businessman and climate kibitzer named Stephen McIntyre that 1934--and not 1998 or 2006--was the hottest year on record in the U.S. could not have been better timed. August is the month when temperatures are high and the news cycle is slow, leading, inevitably, to profound meditations on global warming. Newsweek performed its journalistic duty two weeks ago with an exposé on what it calls the global warming "denial machine." I hereby perform mine with a denier's confession.

I confess: I am prepared to acknowledge that Mr. McIntyre's discovery amounts to what a New York Times reporter calls a "statistically meaningless" rearrangement of data.

But just how "meaningless" would this have seemed had it yielded the opposite result? Had Mr. McIntyre found that a collation error understated recent temperatures by 0.15 degrees Celsius (instead of overstating it by that amount, as he discovered), would the news coverage have differed in tone and approach? When it was reported in January that 2006 was one of the hottest years on record, NASA's James Hansen used the occasion to warn grimly that "2007 is likely to be warmer than 2006." Yet now he says, in connection to the data revision, that "in general I think we want to avoid going into more and more detail about ranking of individual years."

I confess: I am prepared to acknowledge that the world has been and will be getting warmer thanks in some part to an increase in man-made atmospheric concentrations of greenhouse gases. I acknowledge this in the same way I'm confident that the equatorial radius of Saturn is about 60,000 kilometers: not because I've measured it myself, but out of a deep reserve of faith in the methods of the scientific community, above all its reputation for transparency and open-mindedness.

But that faith is tested when leading climate scientists won't share the data they use to estimate temperatures past and present and thus construct all-important trend lines. This was true of climatologist Michael Mann, who refused to disclose the algorithm behind his massively influential "hockey stick" graph, which purported to demonstrate a sharp uptick in global temperatures over the past century. (The accuracy of the graph was seriously discredited by Mr. McIntyre and his colleague Ross McKitrick.) This was true also of Phil Jones of the Climatic Research Unit at the University of East Anglia, who reportedly turned down one request for information with the remark, "Why should I make the data available to you, when your aim is to try and find something wrong with it?"

I confess: I understand that global warming may have negative consequences. Heat waves, droughts and coastal flooding may become more intense. Temperature-sensitive viruses such as malaria could become more widespread. Lakes may be depleted by evaporation. Animal life will suffer.

But as Bjorn Lomborg points out in his sharp, persuasive and aptly titled book "Cool It," a warming climate has advantages, too, and not just trivial ones. Though global warming will cause more heat deaths, it will also mean many fewer cold deaths. Drought may increase in some areas, but warming also means both more rain and longer growing seasons. Temperature changes will harm some wildlife in some places. But many species will benefit from a bit more warmth. Does anyone know for certain that the net human and environmental losses from global warming will exceed overall gains?