And all governments at the most recent annual climate negotiations have agreed to set legally binding targets at the 2015 climate summit in Paris.
Hanging over the meeting was the critical question: Will international leaders who come together in December in Paris for what might be the most important global climate negotiations of all time be able to achieve an agreement to keep the world's average temperature from rising by more than 2°C above the pre-industrial average?
He called the coming climate negotiations "the most complicated process the world has ever seen".
The future of the protocol is a key question at the United Nations climate negotiations, because most big developing countries have stipulated that the 1997 treaty must be continued as a condition of any future climate change agreement.
More than 120 heads of state are meeting at a climate summit in New York on Tuesday, convened by the UN secretary-general in the hope that a series of personal meetings will allow them to break the stalemate that has marked climate negotiations for most of the last two decades.
It represents the most significant step forward since international climate negotiations began, more than two decades ago, and the culmination of years of hard work by negotiators in — among many other cities — Washington, Beijing, Bonn, Durban, Cancún, and Lima.
She presided over the Copenhagen summit, arguably the most important talks in 20 years of climate negotiations, which was attended by leaders from nearly every country on the globe, including Barack Obama, Wen Jiabao, Gordon Brown and Angela Merkel.
But the US-China agreement has injected that most precious and rare of commodities into global climate negotiations: momentum.
In contrast to climate change mitigation actions, for which negotiations at the supranational level are required, most climate change adaption actions can be taken at much lower aggregation levels [12], and especially at the local level.
Representatives of most of the world's poor countries have walked out of increasingly fractious climate negotiations after the EU, Australia, the US and other developed countries insisted that the question of who should pay compensation for extreme climate events be discussed only after 2015.
