The Obama administration will evidently be making some big changes in US policy on climate change: Advocates for Action on Global Warming Chosen as Obama’s Top Science Advisers.

President-elect  Barack Obama has selected two of the nation’s most prominent scientific advocates for a vigorous response to climate change to serve in his administration’s top ranks, according to sources, sending the strongest signal yet that he will reverse Bush administration policies on energy and global warming.

The appointments of Harvard University physicist John Holdren as presidential science adviser and Oregon State University marine biologist Jane Lubchenco as head of the National Oceanic and Atmospheric Administration, which will be announced tomorrow, dismayed conservatives but heartened environmentalists and researchers.

Like Energy Secretary-designate Steven Chu, who directs the Lawrence Berkeley National Laboratory, Holdren and Lubchenco have argued repeatedly for a mandatory limit on greenhouse gas emissions to avert catastrophic climate change. In 2007, as chairman of the board of the American Association for the Advancement of Science, Holdren oversaw approval of the board’s first statement on global warming, which said: “It is time to muster the political will for concerted action.”

In October, Lubchenco told the Associated Press that she believed public attitudes on climate change were shifting, adding: “The Bush administration has not been respectful of the science. But I think that’s not true of Republicans in general. I know it’s not.”