clipped from www.cfr.org

The debate on global warming reached a new intensity as the presidential campaign season got underway. The Intergovernmental Panel on Climate Change (IPCC) released the first part of an assessment report in February 2007 that said human activity is “very likely” accountable for global warming and immediate action to stabilize greenhouse gas emissions is necessary. A fourth part of the report, released in May 2007, said the rise in global carbon emissions would need to cease by 2015 to stabilize global temperatures. Democratic candidates seized on the reports as evidence of a need for federal action on carbon emissions. Most Republican candidates, excepting Sen. John McCain, have been wary of embracing federally mandated controls on emissions.