Climate change response will define this century, says Obama

US president Barack Obama has called on world leaders to unite in tackling climate change before it is too late to avert its potentially disastrous consequences. Addressing a UN climate summit in New York yesterday, Mr Obama said "the urgent and growing threat of a changing climate" was an issue that "will define the contours of this century more than any other".

No nation could meet this “global threat” alone, he said. “Nobody gets a pass.”

Outlining how the US was already dealing with the issue on a broad front and intended to do even more, Mr Obama put it in stark terms: “We are the first generation to feel the effects of climate change and the last generation that can do something about it.”

Several other world leaders announced new initiatives, including French president François Hollande, who pledged that his country would contribute $1 billion (€780 million) to the UN’s Green Climate Fund, which has been set up to assist poorer countries.

Notable absentees included German chancellor Angela Merkel, Chinese president Xi Jinping, the Indian prime minister Narenda Modi and Russian president Vladimir Putin, even though they are expected to attend the UN General Assembly later this week.

UN secretary-general Ban Ki-moon, who convened the summit, described climate change as “a defining issue of our age . . . [and] our response will define our future. To ride this storm we need all hands on deck. That is why we are here today. We need a clear vision.”

Rajendra Pachauri, chairman of the UN's Intergovernmental Panel on Climate Change, which issued its most recent assessment earlier this year, warned that the time to take action "is running out".

Acknowledging that while there were costs, they “are nothing compared to the cost of inaction”.

“If we want a chance to limit the global rise in temperature to 2 degrees Celsius, our emissions should peak by 2020. If we carry on business as usual, our opportunity to remain below the 2 degree limit will slip away well before the middle of the century.” This was underlined by a succession of speeches by leaders of small, low-lying island states threatened by rising sea levels.

Anote Tong, president of Kiribati in the Pacific Ocean, said: “I’ve been shouting about climate change for so long I have lost my voice.”

Former US vice-president Al Gore said the path to change was clear. “It leads to a global agreement next year in Paris. To those who have grown cynical about the process, I would remind you of the words of the great poet Wallace Stevens: after the final no, comes a yes.” Mr Gore was referring to the crucial UN climate conference in Paris at the end of next year, at which an international agreement on how to tackle climate change is expected to be concluded.

The summit in New York is designed to add political impetus to the negotiations. Yvo de Boer, a former UN climate chief, said world leaders had not been engaged on climate since the Copenhagen conference debacle in 2009, so the New York summit was useful in “taking the temperature of politics” in the run-up to Paris.

While welcoming the current US "rhetoric", he told the Guardian: "The problem with the US is that it often doesn't go very far beyond the rhetoric. That is, the US is vocal and very demanding in international negotiations and then slips out the door when it is time to sign on the dotted line."