Challenge ahead is to ensure that the enthusiasm translates into firm commitments.
It was always meant to be more about marshalling enthusiasm for a cause than making firm pledges. And, on that front, the United Nations (UN) climate summit delivered. Held on 23 September in New York, the gathering attracted an array of world leaders, activists and celebrities, who expressed grave concern about the effects of unmitigated climate change on the wealth and security of future generations and on vulnerable ecosystems.
Others, however, were left fretting that the world is still doing little to prevent emissions of greenhouse gases from accumulating at a rate that may soon cause severe climatic disruption.
The next challenge will be to ensure that the enthusiasm generated at the meeting translates into firm commitments in time for the UN climate talks scheduled for December 2015 in Paris. The goal of that meeting is to agree on a more ambitious successor to the 1997 Kyoto Protocol — parts of it have now expired, and the United States, then the largest emitter, never ratified it. Although the Paris agreement will be less prescriptive than the Kyoto Protocol, the goal is that it will include more countries and make deeper cuts to emissions.
The meeting in New York was about revving up support ahead of the Paris meeting. “The fundamental purpose was not to negotiate an agreement, but simply to provide support and encouragement for the negotiating process,” says Robert Stavins, an environmental economist at Harvard University in Cambridge, Massachusetts, who chairs the Harvard Project on Climate Agreements. “The presence of, and positive statements from, over a hundred heads of state more than fulfilled that purpose.”
US president Barack Obama was one of the summit’s biggest stars. "We are the first generation to feel the effect of climate change and the last generation who can do something about it," he told the meeting.
After his first term in office achieved little on the climate-change front, Obama had promised after his re-election in 2012 to make the issue a priority, and in June, his administration announced CO2 regulations for all existing US power plants. And China, now the world’s biggest CO2 emitter and deeply concerned about worsening air pollution, has launched market-based schemes aimed at cutting emissions and is investing heavily in clean energy technologies.
The New York meeting produced some pledges. China said that it will cut by 45% the carbon intensity — the amount of emissions per unit of economic output — of its rapidly growing economy. However, experts say that China’s target may sound more ambitious than it actually is, because energy intensity tends to naturally decline in maturing economies.
Rich countries also promised to help mobilize public and private money to finance clean energy in the developing world and help poor countries to adapt to climate change. By 2020, the UN Green Climate Fund, launched in 2011, is to channel up to US$100 billion per year into low-emission technology and climate-resilient development.
“World leaders seem to accept now that climate change is a severe threat and that emission cuts are not necessarily inconsistent with economic growth,” says Glen Peters, a climate policy expert at the Center for International Climate and Environmental Research in Oslo.
But more needs to be done, he says: “Nothing announced at the meeting will get us anywhere near a reasonable chance to limit global warming to safe levels.”
According to greenhouse-gas emission data published just ahead of the meeting1, the world is now on track to substantially exceed warming of 2 ° C above pre-industrial temperatures, which has been widely accepted as a threshold to ‘dangerous’ climate change. To have a 66% chance of keeping clear of that threshold, countries must collectively emit no more than 1.2 billion tonnes of CO2 from 2015 onwards — much less than the volume of known fossil-fuel reserves.
Overall, emissions would need to decrease by an average of 5% a year over the coming decades to stabilize the climate2. But global emissions are now rising by about 2.5% per year and are expected to reach a record 37 billion tonnes in 2014. At that rate, the remaining carbon budget will be exploited within less than 30 years1.
Lack of ambition
“The challenge is clear, but political declarations at the meeting lacked both detail and ambition,” says Malte Meinshausen, a climate scientist at the Potsdam Institute for Climate Impact Research in Germany. It is still unclear, for example, who will review and enforce national commitments within the Paris agreement — which is likely to have only limited legal force and will rely on countries suggesting their own emissions targets.
The fact that pledges made so far will not suffice to limit the average global temperature increases to 2 ºC is “unfortunate, but not of the greatest importance”, says Stavins.
“The negotiating countries are making progress towards reaching a new hybrid agreement that will apply to all countries under a common framework,” he says. “This is of exceptional importance, and it is why I believe the probability of reaching a meaningful agreement is better now than it has been in more than 20 years. “
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Schiermeier, Q. UN climate summit scores high on passion. Nature (2014). https://doi.org/10.1038/nature.2014.16003