Michael E. Mann, The New York Times:

STATE COLLEGE, Pa. — THE overwhelming consensus among climate scientists is that human-caused climate change is happening. Yet a fringe minority of our populace clings to an irrational rejection of well-established science. This virulent strain of anti-science infects the halls of Congress, the pages of leading newspapers and what we see on TV, leading to the appearance of a debate where none should exist.

In fact, there is broad agreement among climate scientists not only that climate change is real (a survey and a review of the scientific literature published say about 97 percent agree), but that we must respond to the dangers of a warming planet. If one is looking for real differences among mainstream scientists, they can be found on two fronts: the precise implications of those higher temperatures, and which technologies and policies offer the best solution to reducing, on a global scale, the emission of greenhouse gases.