Experts skeptical as climate talks begin

Just two years ago, a United Nations panel that synthesizes the work of hundreds of climatologists around the world called the evidence for global warming “unequivocal.”

But as representatives of about 200 nations began talks Monday in Copenhagen on a new international climate accord, they were doing so against a background of renewed attacks on the basic science of climate change.

In this essay Bill McKibben, explains why he is worried -- and why we should be to. Unlike health care, or any other political issues, which can be modified later, climate change cannot be. Time has run out, he says.