The University of California (UC) renewed its commitment to fight climate change at the UC Carbon and Climate Neutrality Summit at UC San Diego Tuesday. University president Janet Napolitano assured California Gov. Jerry Brown and other summit participants that the university’s 10 campuses will continue to act as “living laboratories” for climate change solutions.

“Addressing these challenges, and reducing our carbon footprint, is a moral imperative,” Ms. Napolitano, a former governor of Arizona and Homeland Security secretary, said at the summit.

By the end of this century, a warming climate may wipe out available habitat for some of Hawaii's rarest birds, researchers warned on Wednesday.

The future is particularly dire for certain species living in high elevations, said the study, published in the open-access journal PLOS ONE.

Japan has lofty ambitions to become a "hydrogen society" where homes and fuel-cell cars are powered by the emissions-free energy source, but observers say price and convenience are keeping the plan from taking off.

Prime Minister Shinzo Abe has dubbed hydrogen the "energy of the future", and hopes it will help Tokyo meet the modest emissions targets it has set ahead of a U.N. climate change conference this month.

At her farm nestled in the green hills of northwestern France, Marie-Francoise Brizard is helping to curb a planet-wide menace: farting and belching cows implicated in global warming.

So far this year, Brizard says she has cut methane emissions from her herd of 40 Normandy cows that are equivalent to 32 tonnes of climate-changing carbon dioxide.

A study predicting deadly heat waves in the Persian Gulf by the century’s end has underscored concerns about the effects of rising global temperatures on cities in other parts of the world, including the United States.

Monday’s report in the journal Nature Climate Change warned that Persian Gulf cities could experience extreme summer temperatures that are literally too hot for human survival. But scientists say climate change will inevitably lead to hotter, longer heat waves and higher rates of heat-related deaths across large swaths of the planet.

At least 80 world leaders, including Barack Obama, Xi Jinping, David Cameron and Narendra Modi, will attend a summit tasked with agreeing a global climate pact in Paris in December.

Diplomats endorsed the outlines of the proposed deal in Bonn on Friday after five days of fraught negotiation that highlighted just how much work remains to be done in Paris.

Stopping the underwater carbon emissions time bomb could require widespread seagrass transplantation.

Seagrass is up to 35 times more efficient at sequestering carbon than rainforests, and stores it for millennia in the sediment below.

French President Francois Hollande said Monday that Chinese support was "essential" to reaching an effective deal at the forthcoming climate change conference in Paris, as he began a visit to the Asian giant.

In the southwestern megacity of Chongqing, Hollande said he was seeking "a global and ambitious agreement that will allow [global] warming to be limited to two degrees".

Hollywood star Sean Penn said Sunday the upcoming climate talks in Paris were the "last great chance" to stop the planet overheating.

Penn, one of Hollywood's most socially engaged actors and directors, was in the French capital to meet Environment Minister Segolene Royal with less than a month to go until the 21st United Nations Climate Change Conference begins.

The sign -- "risk of drowning" -- outside one of Rio de Janeiro's freshwater reservoirs looks like a joke: there's no water here left to drown in.

Instead, the Saracuruna reservoir near Duque de Caxias, outside Rio, is an expanse of sand, mud and vegetation. Four stray dogs scamper and cattle come to drink from a stream still running through the middle.