Heat Rises Between Greenhouse Guru, Naysayer

WASHINGTON, D.C.--A congressional hearing here today to discuss the Clinton Administration's proposal for cutting greenhouse gases turned into a heated exchange between two of the most visible scientists on opposite sides of the debate. The White House plan, released last month, would reduce carbon dioxide emissions to 1990 levels between 2008 and 2012; it is one of several proposals to be considered when countries meet next month in Kyoto, Japan, to sign a global warming treaty.

Facing off before the House Science Subcommittee on Energy and Environment were Robert Watson, brand-new chair of the Intergovernmental Panel on Climate Change--whose 1995 report concluding that human activity is warming the atmosphere prompted the climate negotiations--and University of Virginia, Charlottesville, environmental scientist Patrick Michaels, an outspoken critic of warming predictions who runs a skeptical newsletter funded in part by industry. Subcommittee members seemed most interested in learning whether specific weather phenomena--such as the 1995 heat wave in Chicago and the receding glaciers at Glacier National Park in Montana--could be attributed to global warming. Watson responded that while one "can't attribute any single event" to global change, "it's totally consistent."

Michaels, however, argued that Montana's glaciers began melting long before World War II, when temperatures began to rise after a "little ice age" in the mid-1800s. "Bob created an impression that was wrong," he said, and added later, "things are being misrepresented and exaggerated."

Watson, for his part, retorted that several slides Michaels flashed before the subcommittee showed temperature data for periods too brief--only a decade or two--to indicate any kind of warming trend. All the evidence should be taken into account, Watson said, "rather than trying to debate the bumps and wiggles in the Congress."

At one point amid the rancor, Michaels presented an analysis showing that, if implemented worldwide, the White House proposal would, by 2050, reduce average global temperatures by a mere 0.13 degrees Celsius. "Behold the warming saved," Michaels said sarcastically. "It's so small it could not be measured by surface thermometers." No lawmakers asked him to elaborate.