Science Dec 07 Watch EPA: Greenhouse Gases Pose Danger to Humans In an interview with Gwen Ifill, EPA Administrator Lisa Jackson explains the decision to declare greenhouse gases a danger to human health.
Science Dec 07 Watch Diplomats in Copenhagen Seek Pact on Emissions As an international climate summit kicked off in Copenhagen on Monday, the EPA took a step toward regulating greenhouse gases by declaring them a risk to human health. Kwame Holman reports.