Editor's Letter; June 2009; Scientific American Earth 3.0; by Mark Fischetti; 1 Page(s)

The climate challenge just became a lot more challenging. We know that man-made carbon dioxide emissions are accelerating global warming. But intrepid research has revealed an additional sinister threat: methane. As Sarah Simpson reports on page 30, the warming of the Arctic is releasing vast quantities of methane that has been locked away for centuries in formerly frozen soil. Once released, methane traps 25 times more heat in the atmosphere than carbon dioxide does. So it is more imperative than ever to slash greenhouse gases quickly, to slow the venting of methane.

The single boldest stroke must come from Congress. The House and Senate are debating legislation that would impose either a cap-and-trade system or a tax on carbon emissions (for updates see www.ScientificAmerican.com/Earth3). Certain politicians and CEOs are trying to talk Congress out of it. Our representatives should dismiss the detractors and pass legislation, before November. That deadline is crucial: nations will meet in December in Copenhagen to hammer out new international agreements to limit emissions. The U.S., shamefully, has never signed such a protocol, and leaders worldwide have said, plainly, that the Copenhagen talks will fail if the U.S. does not enact legislation to clean up its own backyard.