By the same token, he says, there is a financing advantage in being on the greenhouse bandwagon. Are some people trying to maintain a sense of crisis to get research grants? "Yes," he says, "and it's unconscious and it's natural."

One who says he basically agrees with Dr. Lindzen's view is Dr. William Gray of Colorado State University, best known for his predictions of hurricane activity. "A lot of my older colleagues are very skeptical on the global warming thing," said Dr. Gray. He calls Dr. Lindzen's stand "courageous." While some of the criticisms delivered by Dr. Lindzen may have some flaws, said Dr. Gray, "across the board he's generally very good."

Another atmospheric scientist cited by Dr. Lindzen as a fellow skeptic, Dr. John M. Wallace of the University of Washington, said there are "relatively few scientists who are as skeptical of the whole thing as Dick is." Many more, said Dr. Wallace, take the question of climate change seriously but think that assertions of climate change already in progress have been exaggerated, as he does.

The object of the conflicting opinions was born in Webster, Mass., in 1940, after his parents fled Hitler's Germany. His shoemaker father later moved the family to the Bronx, where, Dr. Lindzen says, "I think we were the first Jewish family in an Irish-Catholic neighborhood." There he developed a lifelong enthusiasm for amateur radio and won Regents' and National Merit scholarships at the Bronx High School of Science (class of 1956). He also acquired the middle-class native New Yorker's hardened "G" (as in Lon-GIH-land) that faintly modifies his otherwise straightforward academic accent today.

The scholarships propelled him as a student first to Rensselaer Polytechnic Institute and then to Harvard University, where he was attracted by classical physics, and then atmospheric physics. By his mid-30's he had produced landmark work in atmospheric dynamics, mainly involving "tides," or regular changes in atmospheric pressure, and the periodic shift in direction of high-level equatorial winds that affect global circulation patterns. After various academic posts, he joined the M.I.T. faculty in 1983, where he is the Alfred P. Sloan Professor of Meteorology.

In recent years, while pursuing his main interest of atmospheric dynamics in trying to help "figure out how climate works," he has leveled a variety of criticisms at the idea of serious climatic change, some with telling effect. For instance, he points out, the computer models do not reflect the climate's natural variability very well -- a key shortcoming in trying to gauge the human effect on climate, one that is readily conceded by the modelers.

But the Lindzen idea that has attracted most attention is based on a fundamental point of physics: that carbon dioxide and the other waste gases generate only a small amount of warming. Something has to amplify that warming for the larger amount of warming predicted by the United Nations panel to materialize. The main candidate, whose presumed amplifying effect is built into the computer models, is water vapor -- also a heat-trapping gas, and the most powerful one since there is so much of it and it is so pervasive. The theory is that a warmer atmosphere holds more water vapor, thereby increasing the warming even more. Without this amplification, Dr. Lindzen argues, the average global temperature will rise by only about a degree Fahrenheit if atmospheric carbon dioxide is doubled.