In the 2008 presidential debates, moderators Tom Brokaw (second debate) and Bob Schieffer (third debate) asked presidential nominees Barack Obama and John McCain about climate change and reducing American dependence on oil. Both candidates vigorously supported reductions in carbon pollution, though the means to that end differed.

Since that election, the scientific evidence that climate change is real and human-caused has only grown. The health impact and economic costs of the extreme weather events and record temperatures of 2010, 2011, and 2012 are a 10-alarm warning that climate change poses a real threat to Americans and the world. And unlike in 2008, there is a clear difference between the candidates on whether to slow this looming disaster, let alone how to solve it.