The science is settled

Even some who remain skeptical about the extent or pace of global warming say that the premise underlying the Copenhagen talks is solid: that warming is to some extent driven by greenhouse gases spewing into the atmosphere from human activities like the burning of fossil fuels and deforestation.

Roger A. Pielke Sr., for example, a climate scientist at the University of Colorado who has been highly critical of the United Nations climate panel and who once branded many of the scientists now embroiled in the e-mail controversy part of a climate “oligarchy,” said that so many independent measures existed to show unusual warming taking place that there was no real dispute about it. Moreover, he said, “The role of added carbon dioxide as a major contributor in climate change has been firmly established.”…

Greenhouse gases warm the planet by letting in sunlight and blocking the escape of some of the resulting heat. “The physics of the greenhouse effect is so basic that instead of asking whether it would happen, it makes more sense to ask what on earth could make it not happen,” said Spencer Weart, a physicist and historian. “So far, nobody has been able to come up with anything plausible in that line.”…

In reaching its conclusion, the climate panel relied only partly on temperature data like that collected by the scientists at the Climatic Research Unit at the University of East Anglia, whose circulated e-mail correspondence set off the current uproar. It also considered a wide range of data from other sources, including measurements showing the retreat of glaciers in mountain ranges around the world, changes in the length and character of the seasons, heating of the oceans and marked retreats of sea ice in the Arctic.