U.S. Emitted 20% of Global-Warming Gases From 1750 to 2005, Match Says - Bloomberg

The U.S. emitted 20 percent of the world’s global-warming gases from 1750 through 2005, and China accounted for 12 percent, according to a group of scientists.
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In the six decades through 2050, China will contribute most of the world’s emissions, or 17.6 percent. That compares with 12.1 percent for the U.S. and 8.2 percent for India, according to the data, which relies on previously published data from the Intergovernmental Panel on Climate Change, the UN’s climate- science group.

Global impact of EU 30 pct carbon cut small:IEA | Reuters

Fatih Birol, of the IEA, said the gains from the tougher EU reduction target would roughly equal only two weeks of China's emissions.
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"The wind is not blowing in the right direction for fighting global warming. Frankly, there are virtually no chances for the Cancun summit to end in legally binding agreement," Birol said, adding, "I would be very happy to be proven wrong on this."