The recent announcement by EPA , declaring that greenhouse gases are a danger to public health and welfare, should not come as a surprise to anyone. EPA has made it clear that it would respond to what the science demanded and to what the Supreme Court (Mass v. EPA ) mandated.
The endangerment finding, by itself, does not regulate any sources, but it lays the necessary foundation for future EPA regulations. The likely first one will be the recently proposed light duty vehicle and engine rule  which is scheduled to be finalized in March 2010.
But EPA’s future actions are best viewed in the broader context of other activities also aimed at reducing greenhouse gas emissions. State and regional partnerships have stepped up to the plate over the past several years and now 23 states  either have or are developing programs to regulate greenhouse gas emissions. In addition, several recent court decisions (see for example, Conn. v. AEP ) have opened the door for common law nuisance claims against firms emitting greenhouse gas emissions.
Both the judicial and executive branches of our government have answered the call and have begun to actively address concerns about climate change. Now is the time for Congress to take control and pass comprehensive clean energy and climate legislation. A broad consensus exists that comprehensive legislation would be far more cost effective than leaving the field to individual states, EPA or the judiciary. The path forward in the Senate won’t be easy, but it certainly is necessary.
Despite the recent hue and cry  over hacked e-mails , the overwhelming scientific evidence supports the link between greenhouse gas emissions and climate change. Yes, there are certainly aspects of some of the recently exposed e-mails that suggest scientists themselves can act peevishly toward one another and more substantively, that better guidelines for making data available and transparent might be useful. But let there be no mistake, the compelling evidence from multiple data sets and from multiple lines of research hasn’t changed. The words of a recent report by the US Global Change Research Program  resound loud and clear, “global warming is unequivocal and primarily human induced.”
The case for Senate action is also unequivocal.
Steve Seidel is Vice President, Policy Analysis