The United Nations climate meeting in Warsaw is laying the groundwork for a treaty to replace the Kyoto Protocol. Credit: JANEK SKARZYNSKI/AFP/Getty Images

At a major United Nations climate summit in Warsaw this week, a plan is being hammered out for negotiations on a new climate treaty to be finalized in Paris in two years’ time. Delegates from 195 nations are also seeking to obtain commitments from countries to limit their greenhouse-gas emissions between now and 2020. But the path forward is rife with disputes between rich and poor countries over funding, and how to allocate and enforce emissions reductions.

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The conference aims to outline the schedule and to set parameters for negotiations ahead of the next major climate summit in Paris in 2015, when countries hope to forge a treaty to follow the 2009 agreement settled on in Copenhagen.

At that meeting, negotiations over a formal treaty broke down, but eventually resulted in a set of non-binding pledges — the Copenhagen Accord — for emissions reductions until 2020. The accord also blurred the distinction between developed countries, which were bound by the 1997 Kyoto Protocol to reduce emissions, and developing countries, which had no such obligations. Since then, negotiators have worked on how to structure a new framework that would involve climate commitments from all countries — including China, now the world’s largest emitter, and the United States, which never ratified the Kyoto Protocol (E. Diringer Nature 501, 307–309; 2013).

The Warsaw talks are split into two main tracks. One focuses on the architecture of a new global climate treaty that would take effect after 2020, when the current Copenhagen commitments expire. The second examines what can be done to strengthen commitments between now and 2020 to increase the chance of limiting global warming to a target of 2 °C above pre-industrial temperatures (see ‘Emissions up in the air?’).

The European Union (EU), for example, has proposed a multi-stage process, whereby commitments for climate action post-2020 would be registered next year and then subjected to an international assessment to determine how well the commitments measure up against each other and against scientific assessments. The final commitments would then be registered in Paris in 2015. By getting countries to volunteer their climate commitments and comparing them in this way, the hope is that nations with unambitious targets might be shamed into strengthening them. The EU has also called for a review of pre-2020 commitments.

Credit: Source: PBL Netherlands environ. assessment agency/unep/climate policy initiative

Tasneem Essop, who is tracking negotiations for the environmental group WWF in Cape Town, South Africa, says that these short-term commitments are crucial for pointing the world in the right direction. “The biggest challenge will be to ensure that emissions do peak within this decade,” she says.

The cost of reducing emissions could be the first flashpoint in Warsaw. In Copenhagen, developed countries agreed to provide US$30 billion in climate aid from 2010 to 2012, and to increase climate support to developing countries to $100 billion annually by 2020. Although the short-term commitments were largely met, there is no clear plan for attaining the goal of $100 billion a year. From emerging giants such as Brazil and China to poor countries in Africa, developing nations are demanding that wealthy countries ramp up funding and create a viable path to this goal.

With public coffers strapped, many developed nations are looking for other funding sources. One possibility is to place some type of levy on international aviation, which is being considered by the International Civil Aviation Organization in Quebec, Canada. The body has committed to craft an agreement by 2016 that could take effect by 2020.

Negotiators in Warsaw will haggle over how to finance and ultimately deploy climate aid through organizations such as the newly launched Green Climate Fund, based in Incheon, South Korea. Another flashpoint is the developing countries’ demand for a ‘loss and damage’ mechanism to compensate poor countries irreparably harmed by climate change.

But the biggest questions will centre on the framework for the treaty in 2015. Before Copenhagen, the emphasis was on a treaty similar to the Kyoto Protocol that would lock in legally binding emissions reductions. In Copenhagen, the United States and other developed countries pushed for an alternative that would allow individual countries to register commitments, which would then be reviewed at an international level. Delia Villagrasa, a senior adviser for the European Climate Foundation in Brussels, says that the talks are moving towards this bottom-up approach, which would be combined with a formal review to assess commitments and identify ways to scale them up. The world could get its first hint of what such a system might look like as the talks wrap up next week.

“Warsaw will bring some clarification on the structure of the new agreement,” Villagrasa says. “That’s not sexy for the media, but it’s important.”