Today is Day 1 of the U.N.'s climate change conference in Copenhagen.
The Associated Press reports diplomats from 192 nations are being told this is the last, best chance for a deal to protect the world from calamitous global warming. But a series of promises by rich and emerging economies to curb their greenhouse gases spawned optimism as the summit got under way in Copenhagen.
President Barack Obama has announced he will appear at the climate summit next week.
The president had planned to visit the summit for one day this week as a detour on his trip to accept the Nobel Peace Prize in Oslo. Now he will attend on Dec. 18, a time when leaders from other countries, including China and India, will be on hand. Observers say that the change -- along with specific proposals that have recently been put on the table -- mean a more significant agreement is possible.
"This is a very significant development, which in substance and symbolism greatly enhances the prospects of a satisfactory agreement at Copenhagen," Rajendra Pachauri, whose Intergovernmental Panel on Climate Change shared the Nobel Peace Prize with former Vice President Al Gore in 2007, said about Obama's plans, according to The Associated Press.
The U.S. plans to propose a cut in emissions in the range of 17 percent from 2005 by 2020, regardless of the growth of its economy.
On Thursday, India said it would cut the ratio of greenhouse gases pollution to production by 20 to 25 percent from 2005 levels by 2020 but would not agree to hard limit on the amount of heat-trapping gases it could release. That means the aggregate of emissions can keep rising as its economy develops, but limits how quickly. China has made a similar proposal for its own emissions.
"There are still outstanding issues that must be negotiated for an agreement to be reached, but this decision reflects the president's commitment to doing all that he can to pursue a positive outcome," White House press secretary Robert Gibbs said in a statement.
NOTE SINCE THIS ARTICLE WAS POSTED: This article was updated 12/7 to reflect that the conference is now underway.