Key provisions of the Kyoto Protocol expire in December of 2012, and experts say there's no real global framework in place to replace the treaty that was supposed to be the first step toward ambitious actions on climate change. Above, a coal-fired power plant in eastern China. China is now the leading carbon dioxide emitter in the world. AFP/Getty Images hide caption

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The U.S. is second only to China in emitting gases that cause global warming. Above, the smoke stacks at American Electric Power's Mountaineer power plant in West Virginia. Saul Loeb/AFP/Getty Images hide caption

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A U.N. climate panel says that we can expect more extreme weather conditions as a result of climate change. Above, people run from a high wave on Nov. 8 in Nice, France, where heavy rain and flooding forced hundreds to evacuate. Vallery Hache/AFP/Getty Images hide caption

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Power plants that burn fossil fuels release carbon dioxide as well as a complex soup of chemicals, including nitrogen and sulfur. These chemicals in the air actually help keep global warming in check by reflecting sunlight back into space. Above, the Bruce Mansfield Power Plant in Shippingport, Pa. Robert Nickelsberg/Getty Images hide caption

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A section of the fusion machine being tested at General Fusion's facility outside of Vancouver, British Columbia. General Fusion is hoping to implement a long-shot strategy that could produce fusion energy in the next few years. Brett Beadle for NPR hide caption

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To feed China's insatiable demand for coal, U.S. companies are trying to sell and ship the lucrative commodity to the Asian market from new West Coast ports. Above, the cooling towers of a coal-fired power plant are seen on the outskirts of Beijing.

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Bellingham, Wash., a progressive college town of 81,000, could soon be home to a new coal terminal. Developers want to ship the lucrative commodity to China, but some locals are worried about the potential environmental impacts.

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A giant dioon, seen at the United States Botanic Garden, is part of the cycad family and can be found growing in Mexico and Central America.

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Daniel Shechtman (left) discusses the quasicrystal's structure with collaborators in 1985, just months after shaking the foundations of materials science. Shechtman was awarded the 2011 Nobel Prize for chemistry.

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A neutrino detector like this one, seen at Los Alamos National Laboratory in 1995, was used to collect data claiming that neutrinos can travel faster than the speed of light. Fred Rick/Time & Life Pictures/Getty Image hide caption

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Ice on the Arctic Ocean has melted to its second-lowest level on record. Above, ice in a fjord in Greenland. Slim Allagui/AFP/Getty Images hide caption

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