After days of bitter fighting and an overtime stretch filled with twists and turns and even tears, world leaders on Saturday came to agreement on a rough roadmap for developing a new global climate treaty by 2009. The European Union had pushed for industrialized countries to commit to cuts in greenhouse-gas emissions of 25 to 40 percent by 2020, but the U.S., Canada, and Japan, among others, said no way. The final, agreed-upon text lacks specific numbers, but says that “deep cuts” in emissions are needed.

The U.S. also refused to back compromise language that called on rich nations to provide more technological help to poorer ones; that move elicited boos and an impassioned plea from a Papua New Guinea representative to the U.S.: “We seek your leadership. But if for some reason you are not willing to lead, leave it to the rest of us. Please, get out of the way.” Believe it or not, the U.S. then did get out of the way, changing its position and saying it would support the agreement.

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The agreement also calls for developing nations to get credit for protecting their tropical forests, and for a special fund to help developing nations cope with the effects of climate change.

The “Bali roadmap” will now guide a two-year process of finding a new set of emission-reduction targets to replace those in the Kyoto Protocol, which expires in 2012. But the road is sure to be bumpy. Just hours after the deal was reached, the White House expressed “serious concerns” about it.

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