Every year since 1995, the world’s nations have sent delegates to discuss how best to prevent and prepare for global warming. This is done under the auspices of the United Nations Framework Convention on Climate Change.
In the 1990s, 191 nations agreed to the Kyoto Protocol, an international treaty that committed many wealthier countries to cuts in greenhouse gas emissions. Although some nations (particularly in Europe) took the treaty seriously, the United States never ratified the treaty, and other large developing nations — like China and India — were never obligated to cut emissions.
At the moment, negotiations over a successor to the Kyoto Protocol are dragging along. Last year, every nation in the world agreed to put forward its own voluntary plan for reducing emissions. The United States, for instance, has pledged to cut emissions at least 26 percent between 2005 and 2025. China has pledged that its emissions will peak around 2030.
The idea is that these voluntary plans will be stitched together into some sort of global climate agreement, to be negotiated in Paris at the end of 2015. Early estimates suggest that any such agreement is likely to be weak, putting the world on course for at least 3°C of warming — well above the international goal of limiting global warming below 2°C.
There are plenty of contentious questions that come up over and over in these climate talks. Like: should wealthy countries like the United States and Europe bear a heavier burden for the cuts? What about high-emitting but poorer countries like China and India? And should the wealthy nations that have contributed most to global warming offer aid to the poorer countries who may get hit hardest by climate change?