"The changing global climate will pose profound strategic challenges to the united states in coming decades, raising the prospect of military intervention to deal with the effects of violent storms, drought, mass migration and pandemics, military and intelligence analysts say."

"There might be a scientific reason that the old-growth trees in Yosemite National Park don't seem quite as big or as plentiful as those in your grandfather's early snapshots of the park."

EPA Administrator Lisa P. Jackson said the agency will look at new evidence in reconsidering the Bush-administration decision not to regulate perchlorate in drinking water.

"Three major glaciers in Alaska and Washington state have thinned and shrunk dramatically, clear signs of a warming climate, according to a study released Thursday by the U.S. Geological Survey."

"In a matter of years or decades, researchers believe, animals and plants already are adapting to life in a warmer world. Some species will be unable to change quickly enough and will go extinct, but others will evolve, as natural selection enables them to carry on in an altered environment."

"Psychological barriers like uncertainty, mistrust and denial keep most Americans from acting to fight climate change, a task force of the American Psychological Association said on Wednesday."

"With the fight over health care reform absorbing all the bandwidth on Capitol Hill, Democrats fear a major climate change bill may be left on the cutting-room floor this year."

"Mexico aims to put a detailed offer to cut the growth of its own greenhouse gas emissions on the negotiating table at global climate change talks in Copenhagen this year, a senior environmental policymaker said."

"Secretary General Ban ki-moon today announced plans to fly from Norway out over the Arctic Ocean to the Norwegian research vessel Lance near the North Pole on September 1. The planned excursion is part of his efforts to prod world leaders to take meaningful steps on global warming in treaty talks in Copenhagen in December."

White roofs, a measure recently urged by Energy Secretary Steven Chu, are catching on both as a way of fighting global warming and a way to cool houses cheaply.

"Is it possible that the long performance of the 'You first, sir,' vaudeville routine by the Alphonse and Gaston of the global greenhouse is drawing toward a close?"

"In an interview with Yale Environment 360, John Kerry praises the carbon cap-and-trade legislation now being debated in the U.S. Senate, describes its importance to upcoming climate talks in Copenhagen, and explains how he plans to help the landmark legislation clear the Senate and become law."

What do you buy when you buy a carbon offset? Susan Hess follows the $4.50 she paid to offset the CO2 emitted for a train trip to Seattle in Gorge Outdoors, July 24, 2009.

"Electric utilities boosted lobbying in the second quarter of 2009, narrowing the gap with oil and gas companies that had dominated spending on persuasion by a wide margin earlier this year."

"The fate of major climate legislation in Congress could rest with North Dakota."