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Climate optimism builds ahead of Paris talks

Emission pledges raise hopes for an international treaty.

The climate talks that begin this month in Paris will be attended by several heads of state. Credit: Benoit Tessier/Reuters/Corbis

The road to a new global climate treaty has been slow and plodding. But years of delicate negotiations have given way to cautious optimism as more than 190 nations prepare for the marathon climate talks that begin in Paris on 30 November.

Some long-running disputes remain, such as the debate about what cuts in greenhouse-gas emissions can be expected of developing nations compared with their developed counterparts. But there are many signs that the summit, convened by the United Nations, will succeed in crafting a global climate agreement. These include significant commitments by several major players, including the United States and China, to reduce emissions of greenhouse gases.

Nature special: 2015 Paris climate talks

“We are in for some tense negotiations, but I think we’ll come out of the other end with an agreement,” says Saleemul Huq, director of the International Centre for Climate Change and Development in Dhaka, Bangladesh, and adviser to a negotiating bloc of the least-developed countries.

And although Paris is still reeling from the deadly terror attacks of 13 November, which led the authorities to increase security for the meeting and cancel a big climate march, more than 130 heads of government and state are still expected to attend the two-week summit.

The last major push for a climate treaty faltered in Copenhagen six years ago over whether developing countries should be asked to match developed countries and make voluntary commitments to reduce emissions. The political situation has evolved since then and more than 165 countries have submitted pledges to combat climate change. Although these pledges would not cut greenhouse-gas emissions enough to meet the UN goal of limiting global warming to 2 °C above pre-industrial levels, they show a level of commitment that was missing in Copenhagen.

“Countries are bringing more political will than ever before, and so we’ll see if the process can deliver,” says Elliot Diringer, executive vice-president of the Center for Climate and Energy Solutions, an environmental think tank in Arlington, Virginia. “This agreement has the potential to be a significant turning point.”

Despite a lingering — and potentially volatile — debate about whether those commitments will be legally binding under international law, they are expected to remain voluntary. One of the biggest obstacles to a binding agreement is the US Senate. On 17 November, Republican senators pushed through legislation seeking to block regulations to limit greenhouse-gas emissions from power plants. US President Barack Obama can veto these bills, but he cannot force the Senate, which has the power to reject or approve treaties, to endorse a climate agreement that includes binding limits on greenhouse-gas emissions.

As a result, much of the debate will centre on creating mechanisms that allow governments — and civil society — to monitor progress, build trust and ensure accountability. Environmentalists and many governments are pushing for a five-year review period that would begin immediately after the Paris talks end; governments would need to return to the table with new commitments in 2020.

Huq says that this exercise is particularly important for poor and vulnerable countries, which are pushing for a long-term goal of limiting warming to 1.5 °C. The world is likely to cross a landmark threshold, the 1 °C mark, for the first time in 2015, and Huq admits that stabilizing at 1.5 °C would require emissions reductions so drastic as to be politically impossible at this point. But world leaders should acknowledge that even 2 °C of warming comes with significant impacts on the world’s poorest citizens, he says. “We know we are not going to get everything we want in Paris, but it’s symbolic.”

Samantha Smith, leader of environmental group the WWF’s Global Climate and Energy Initiative in Oslo, says that the biggest debate in Paris will be over financial aid to help poor countries to reduce their emissions and cope with the impacts of climate change. In 2010, wealthy nations established a Green Climate Fund and committed to increase climate aid to US$100 billion annually by 2020. Developing countries will be looking for details about that commitment and what comes next.

The good news, Smith says, is that the conversation about climate action has changed, not just within the negotiations but among faith groups, the general public and businesses, many of which will make their own voluntary emissions commitments in Paris. But she cautions that a new global treaty is just a first step. “When we walk out of there, we are still going to have a lot of work to do.”


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Nature special: Paris Climate Talks 2015

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United Nations Framework Convention on Climate Change

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Tollefson, J. Climate optimism builds ahead of Paris talks. Nature 527, 418–419 (2015).

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