Earth Matters

Generals, admirals say climate change a matter of national security

Video: Chris Matthews debates global warming denying politician

Video: Jon Stewart interviews EPA chief

The new frontier: Sustainable polar retreats

EPA Chief Lisa Jackson hits The Daily Show

Rep. Joe Barton introduces industry-serving dirty energy plan

San Francisco's solar initiatives paying off

Turbine plan received first permits

Media Mayhem: What’s in a name?

Animal Exploration: Panamanian Golden Frogs

Animal Exploration: Planting trees

Green States: Best of the worst