Air travel is the largest unregulated source of carbon pollution in the U.S. -- but not for long.
But there's not much evidence that it has so far -- in part because oil and gas companies won't share their data.
Scientists used the Medea program to study how global warming could worsen conflict. Now that project has come to an end.
Developing countries are poised to lead the world on clean energy investment.
The presidential wannabe isn't a climate denier, yet he opposes cap-and-trade and just about anything else that might curb emissions.
Marc Cornelissen and Philip de Roo were studying the Arctic's lowest winter ice cover on record. Then they fell through it.
California has the most ambitious climate plan in the nation, but if it loses too many trees to fire, it will have a hard time meeting its targets.
It's already looking bad, and it's going to get worse.
The Fukushima disaster screwed up Japan's climate strategy.