The international conference on global warming will begin December 7th in Copenhagen, Denmark. Before that time the U.S. government will make a proposal about specific targets for emission reductions. This will be a complete reversal of the American official stance of the past nine years.
No legislation will have passed through Congress before December 7, so the White House position will be necessarily "nuanced" to take into account the tender feelings of the Congress. The House has passed a bill that calls for a 17% greenhouse gas emission reduction by 2020. The bills being bandied about the Senate set a slightly more aggressive goal. But like much in Washington it's all smoke and vapor, until it's real. And there'll be no official energy and climate legislation out of this Congress this calendar year. The Senate now expects to talk energy in the spring. Assuming the healthcare bill doesn't prove fatal. (Just kidding.)
Meanwhile, the EPA is back there studying and preparing. The EPA has already said it will begin to curtail emissions from major American industries, having declared CO2 emissions a public health hazard.