US President Barack Obama told world leaders that the climate talks that opened on Monday in Paris mark a turning point for collective action on global warming and stand as a rejection of the terrorists who struck the French capital a little more than two weeks ago.
The threat posed by climate change is the defining challenge of the century, Mr Obama told the United Nations-sponsored summit organised to reach the first truly global agreement to curb greenhouse gases. Linking the meeting to the battle against extremism, Mr Obama said a deal on emissions limits would be "an act of defiance" that proves nothing will deter nations from "building the future we want for our children".
"Here in Paris we can show the world what is possible when we come together, united by a common effort and a common purpose," Mr Obama added.
The president told the assembled dignitaries that no nation was immune from the effects of climate change. He said the US, the world's biggest economy and its second-biggest emitter of greenhouse gases, accepted its role for contributing to the problem and shares the responsibility to fix it. "As the leader of the world's largest economy and the second-largest emitter ... the United States of America not only recognises our role in creating this problem, we embrace our responsibility to do something about it," Mr Obama said.
One of the central US goals at the summit is to get commitments from the wealthiest nations to invest in clean energy research and assist developing countries in mitigating the effects of climate change.
The president is looking to advance that effort by highlighting both public and private efforts, including an unprecedented commitment from donors including Microsoft Corp co-founder Bill Gates to pour billions of dollars into basic energy research over the next five years.
Nearly 30 of the world's wealthiest investors will participate in the programme, which is dedicated to providing seed funding to new technologies that can help expand the use of clean energy, particularly in the developing world.
"Given the scale of the challenge, we need to be exploring many different paths, and that means we also need to invent new approaches," Mr Gates said in a statement released on Sunday.
Some 20 countries, including the world's biggest carbon emitters in the US, China, and India, have also agreed to increase spending in that area from US$10 billion to US$20 billion over the next five years.
The move "should send a strong signal to the markets" that leaders from the world's largest carbon emitters are "going all-in on clean energy", White House senior adviser Brian Deese said in a conference call with reporters.
While leaders in Paris are eager to demonstrate that unity, that consensus has not quieted critics of Mr Obama's agenda back at home.
Even as the US hopes to cement its standing as a global leader on climate change, a group of influential congressional Republicans are hoping to use the summit to undercut the president's ambitions and scale back American funding for international efforts to combat global warming.
The White House has downplayed concerns that Republicans could undermine the talks by restricting the State Department's ability to donate to the Green Climate Fund, the central mechanism which leaders are expected to use to assist developing countries. The administration has pledged US$3 billion to the international effort, with the White House requesting US$500 million of that funding this year.
The White House has aggressively courted corporate interests ahead of the talks, soliciting significant pledges and contributions that Mr Obama intends to use as examples of how the US is acting even without congressional assistance.
The old goal of seeking a legally binding international treaty, certain to be dead on arrival in the Republican-controlled US Congress, has been replaced by a system of national pledges to reduce emissions. Some are presented as best intentions, others as measures legally enforced by domestic laws and regulations.
The biggest difference may be the partnership between the United States and China. The world's two biggest carbon emitters, once on opposite sides on climate issues, agreed in 2014 to jointly kick-start a transition away from fossil fuels, each at their own speed and in their own way.
The US and China "have both determined that it is our responsibility to take action", Mr Obama said after meeting Chinese President Xi Jinping. "Our leadership on this issue has been absolutely vital."
Mr Xi said it was crucial climate talks in Paris addressed economic differences between nations and allowed different countries to develop their own solutions to the problem of global warming.
China, the world's top emitter, has always insisted that developed nations had to take the most responsibility for warming the planet and emerging economies needed to be given freedom to develop. "It is important to respect the differences among countries, especially developing countries," Mr Xi told delegates in Paris.
Some 150 heads of state will urge each other to find common cause in two weeks of bargaining to steer the global economy away from its dependence on fossil fuels. They arrived at the climate change talks in Paris armed with promises and accompanied by high expectations.
After decades of struggling negotiations and the failure of a previous summit in Copenhagen six years ago, some form of landmark agreement appears all but assured by mid-December. Warnings from climate scientists, demands from activists and exhortations from religious leaders like Pope Francis, coupled with major advances in cleaner energy sources like solar power, have all added to pressure to cut the carbon emissions held responsible for warming the planet.
Most scientists say failure to agree on strong measures in Paris would doom the world to ever-hotter average temperatures, bringing with them deadlier storms, more frequent droughts and rising sea levels as polar ice caps melt.
Facing such alarming projections, the leaders of nations responsible for about 90 per cent of the world's greenhouse gas emissions have come bearing pledges to reduce their national carbon output, though by different rates. BLOOMBERG, REUTERS
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