Air Pollution

COPENHAGEN - Delegates to a pivotal climate conference welcomed an Obama administration move Monday to regulate greenhouse gases under existing clean air law, but said they still expect more.

COPENHAGEN - The largest and most important U.N.

MAUNA LOA OBSERVATORY, Hawaii - The readings at this 2-mile-high station show a troubling upward curve as the world counts down to crucial climate talks: Global warming gases are building in the atmosphere at record levels from emissions that match scientists' worst-case scenarios.

GENEVA - Greenhouse gases in the Earth's atmosphere reached record highs in 2008, with carbon dioxide levels increasing faster than previously, the U.N.