The idea that humans are the major cause of climate change, as detailed last week by the Intergovernmental Panel on Climate Change, may not have struck many people as new. But more important than the conclusion by the IPCC that global warming in the last 50 years is “very likely” human-made, was the reaction to the group’s fourth report. Rather than the skepticism and denial that greeted earlier reports, a common reaction this time was: “What can we do about it?”

Speaking to reporters on Feb. 2, Secretary of Energy Samuel Bodman said of the report, “We agree with it, and the science behind it is something that our country has played a very important role in.”

Contrast that to the administration’s reaction to the last report, released in 2001. After its release, the administration asked the National Academies of Science to review U.S. policy on climate change with a focus on areas of uncertainty. Although their report said, “The changes observed over the last several decades are likely mostly due to human activities,” with the usual caveats about “natural variability,” the administration remained unconvinced. In June 2001, White House spokesman Ari Fleischer said, “it concludes that the Earth is warming. But it is inconclusive on why – whether it’s man-made causes or whether it’s natural causes.”

Such thinking is, fortunately, no longer part of the White House response, and attention has turned to reducing greenhouse gas emissions.

President Bush, for the first time in a State of the Union address, talked of “global climate change.” He focused on developing alternative fuel sources to reduce our oil dependence and improve the environment.

In Congress, there will be a flurry of bills, ranging from ones that do little more than acknowledge the problem to proposals for mandated 80 percent reductions in greenhouse gas emissions. With so many approaches – the McCain-Lieberman bill, for example, includes nuclear power to replace high-emissions power plants – even supporters of action on climate change are likely to splinter into different camps, dimming the prospects for any legislation passing. Now, however, that is not all bad as analyses of the numerous bills will show the strengths and weaknesses of the various approaches.

This highlights the importance of creating an office of climate response. This important first step, in a bill to be introduced by Sens. Susan Collins and Joseph Lieberman, would create a “climate czar” who evaluates and coordinates the administration’s plans to reduce greenhouse gases.

With the office and analyses, lawmakers will have a better sense of what is feasible, technologically and economically.

It is not the solution, but it is progress.