Nathan

The New Yorker: Online Only: Content: "Without the natural greenhouse effect, the planet would essentially be frozen. Any basic earth-science textbook talks about the natural greenhouse effect; it's a phenomenon that is not in any way debated. All that the theory of global warming says is that if you increase the concentration of greenhouse gases in the atmosphere, you will also increase the earth's average temperature. It's indisputable that we have increased greenhouse-gas concentrations in the air as a result of human activity, and it's also indisputable that over the last few decades average global temperatures have gone up. As best as can be determined, the world is now warmer than it has been at any point in the last two millennia, and, if current trends continue, by the end of the century it will likely be hotter than at any point in the last two million years. "