In the world of energy politics, the sudden vanishing of the word 'coal' is a remarkable and unprecedented event.

Mark Ruffalo, aka the Incredible Hulk, is the natural gas industry's worst nightmare: a serious, committed activist who is determined to use his star power as a superhero in the hottest movie of the moment to draw attention the environmental and public health risks of fracking.

Climate change is a global issue - from the point of view of the Earth's climate, a molecule of CO2 emitted in Bejing is the same as a molecule emitted in Sydney.

President Obama is in no danger of being judged by history as an eco-radical.

Climate scientists have long pointed to the Southwest as one of the places in the U.S. that is most vulnerable to global warming impacts, especially drought. And if there's one thing that even climate denialists don't dispute, dry things burn.

One of the big questions in the climate change debate: Are humans any smarter than frogs in a pot? If you put a frog in a pot and slowly turn up the heat, it won't jump out. Instead, it will enjoy the nice warm bath until it is cooked to death. We humans seem to be doing pretty much the same thing.

For better or worse, the bulk of coal industry jobs are in Appalachia - and when that coal is gone, so are the jobs.