A proposal by the U.S. Commodity Futures Trading Commission to oversee a greenhouse gas contract on a voluntary Chicago trading exchange shows the agency is staking out its territory before Congress decides which agencies should regulate the country's burgeoning carbon market.

A new U.S. government study on Tuesday adds to a growing list of experts concluding that climate legislation moving through Congress would have only a modest impact on consumers, adding around $100 to household costs in 2020.

A group of small U.S. manufacturers and trade associations is endorsing a bill it says will boost the number of green manufacturing jobs in industries like wind and solar power in the United States.

The U.S. climate bill would give states that are heavily reliant on greenhouse-gas emitting fuels, like coal, more carbon credits on a per capita basis than those that use clean fuels, according to an analysis of the legislation released on Wednesday.

US start-up Joule Biotechnologies hopes to make commercial amounts of motor fuel by feeding engineered organisms high concentrations of carbon dioxide and sunlight, its top executive said.

A leading standard setter for voluntary carbon market offsets said on Wednesday it has eased its rules for Canadian projects that aim to cut emissions of greenhouse gases to issue carbon credits.

The climate bill that the U.S. House of Representatives passed on Friday contains several elements that could begin to push the energy industry away from fossil fuels and toward renewable energy.

There is "scarcely an instrument of U.S. foreign policy" that was not vulnerable to climate change, which scientists say will raise sea levels by melting glaciers and ice sheets on Greenland and Antarctica, Kerry, a Democrat, said at a Council on Foreign Relations meeting.

Rich countries may act on their own to reduce greenhouse gas emissions by developing a carbon market they hope will lure in poor nations even if U.N. climate talks get bogged down, experts said.

Nearly 200 countries have been trying to reach an agreement to replace the Kyoto Protocol on global warming with a December deadline at a meeting in Copenhagen approaching.

Most global industrial companies that emit a lot of greenhouse gases are not adequately detailing their climate strategies in U.S. financial filings, two studies by environmental and investment groups showed on Wednesday.