"An expert panel at the National Academy of Sciences is calling for an early warning system to alert us to abrupt and potentially catastrophic events triggered by climate change."

"NAIROBI, Kenya and GAO, Mali—  The Sahel is an environmentally fragile zone that stretches across Africa just south of the Sahara desert."

"China can learn from U.S. struggles to reduce pollution as it confronts recent high-profile incidents of poor air quality paralyzing major cities, the top U.S. environmental regulator said on Monday."

"The publisher of a controversial and much-criticized study suggesting genetically modified corn caused tumors in rats has withdrawn the paper after a year-long investigation found it did not meet scientific standards."

"FAIRBANKS -- Ounce for ounce, methane has an effect on global warming more than 30 times more potent than carbon dioxide, and it's leaking from the Arctic Ocean at an alarming rate, according to new research by scientists at the University of Alaska Fairbanks."

"We've heard that climate change likely played a very minor role in the havoc that typhoon Haiyan wrought on the Philippines."

"The surface of the sun has been surprisingly calm of late — with fewer sunspots than anytime in in the last century — prompting curious scientists to wonder just what it might mean here on Earth."

"WARSAW — Two weeks of United Nations climate talks ended Saturday with a pair of last-minute deals keeping alive the hope that a global effort can ward off a ruinous rise in temperatures."

"Nitrous oxide (N20) emissions could almost double by 2050 if more aggressive action is not taken, undermining global efforts to curb climate change, the United Nations' Environment Programme (UNEP) said on Thursday."

"WARSAW, Poland -- Thirteen environmental and climate justice groups today withdrew from the UN climate change negotiations in Warsaw to protest what they see as lack of action from governments to solve the climate crisis."