An Inconvenient Fact: "There's No Consensus on Global Warming"

Richard Lindzen is the Alfred P. Sloan Professor of Atmospheric Science at the Massachusetts Institute of Technology (here's his Wikipedia entry). Today's OpinionJournal.com has published his article, "Don't Believe the Hype: Al Gore is Wrong. There's No Consensus on Global Warming," which ran earlier in the week in the hard-copy WSJ. Here's some flavor:

According to Al Gore's new film "An Inconvenient Truth," we're in for "a planetary emergency": melting ice sheets, huge increases in sea levels, more and stronger hurricanes, and invasions of tropical disease, among other cataclysms--unless we change the way we live now.

Bill Clinton has become the latest evangelist for Mr. Gore's gospel, proclaiming that current weather events show that he and Mr. Gore were right about global warming, and we are all suffering the consequences of President Bush's obtuseness on the matter. And why not? Mr. Gore assures us that "the debate in the scientific community is over."

That statement, which Mr. Gore made in an interview with George Stephanopoulos on ABC, ought to have been followed by an asterisk. What exactly is this debate that Mr. Gore is referring to? Is there really a scientific community that is debating all these issues and then somehow agreeing in unison? Far from such a thing being over, it has never been clear to me what this "debate" actually is in the first place.

The media rarely help, of course. When Newsweek featured global warming in a 1988 issue, it was claimed that all scientists agreed. Periodically thereafter it was revealed that although there had been lingering doubts beforehand, now all scientists did indeed agree. Even Mr. Gore qualified his statement on ABC only a few minutes after he made it, clarifying things in an important way. When Mr. Stephanopoulos confronted Mr. Gore with the fact that the best estimates of rising sea levels are far less dire than he suggests in his movie, Mr. Gore defended his claims by noting that scientists "don't have any models that give them a high level of confidence" one way or the other and went on to claim--in his defense--that scientists "don't know. . . . They just don't know."

So, presumably, those scientists do not belong to the "consensus." Yet their research is forced, whether the evidence supports it or not, into Mr. Gore's preferred global-warming template--namely, shrill alarmism. To believe it requires that one ignore the truly inconvenient facts. To take the issue of rising sea levels, these include: that the Arctic was as warm or warmer in 1940; that icebergs have been known since time immemorial; that the evidence so far suggests that the Greenland ice sheet is actually growing on average. A likely result of all this is increased pressure pushing ice off the coastal perimeter of that country, which is depicted so ominously in Mr. Gore's movie. In the absence of factual context, these images are perhaps dire or alarming.

They are less so otherwise. Alpine glaciers have been retreating since the early 19th century, and were advancing for several centuries before that. Since about 1970, many of the glaciers have stopped retreating and some are now advancing again. And, frankly, we don't know why.

Read the whole piece. Lindzen's not the only one to note that the global warming debate is far from over. The controversy is a regular discussion topic in my Introduction to World Politics course. As noted in my textbook, James Lee Ray and Juliet Kaarbo's "Global Politics," "There has been considerable debate over predictions of the greenhouse effect. For one thing, it is not entirely clear that industrialization on a worldwide scale willl have a warming effect on the global climate." One authority Ray and Kaarbo cite is Bjorn Lomborg, and his book debunking the greenhouse effect, "The Skeptical Environmentalist."