The world leaders who met at the United Nations to discuss climate change on Tuesday are faced with an intricate challenge: building momentum for an international climate treaty at a time when global temperatures have been relatively stable for a decade and may even drop in the next few years.

Like most large international conferences, the United Nations climate summit meeting in New York this week generated a hefty dose of greenhouse gas emissions.

A United Nations program that has raised $1.2 billion over the past three years for the treatment of H.I.V./AIDS, malaria and tuberculosis through a small fee added to airline tickets sold in 15 countries is going global.

The Environmental Protection Agency said on Tuesday that it would require the nation

Amid a growing split in the business community over climate policy, Pacific Gas and Electric, a major California utility, is withdrawing from the United States Chamber of Commerce, citing

A federal judge has ruled that the government failed to adequately assess the environmental impacts of genetically engineered sugar beets before approving the crop for cultivation in the United States. The decision could lead to a ban on the planting of the beets, which have been widely adopted by farmers.

Global carbon emissions are expected to post their biggest drop in more than 40 years this year as the global recession froze economic activity and slashed energy use around the world.

The decline comes as political leaders are struggling to come up with a common approach to dealing with climate change.

The oil-trading company Trafigura said on Sunday that it had agreed to a settlement with people who say they fell ill after a tanker dumped hundreds of tons of waste around the Ivory Coast city of Abidjan.

The company said it would pay $1,546 a person. The British law firm Leigh Day has said the case involves 30,000 people.

As world leaders gather in New York for the highest-level conference yet on climate change, European leaders are expressing growing unease about the United States

Idyllic scenes of palm trees swaying over sandy beaches have long decorated brochures meant to lure tourists to Indonesia and Malaysia. But few visitors see the giant palm plantations away from the shore.