Paris Climate Agreement
In December 2015, delegates from nearly every country in the world meeting in Paris adopted the first global climate agreement to commit both rich and poor nations to action on greenhouse gas emissions. Negotiated under the United Nations Framework Convention on Climate Change (UNFCCC), the Paris Agreement set the goal of holding the rise in average global temperature to well below 2 degrees Celsius above pre-industrial levels, while pursuing efforts to limit it to 1.5 degrees. It remains the central framework for international climate policy.
The deal followed more than two decades of difficult diplomacy. The UNFCCC was established at the 1992 Rio Earth Summit, and the 1997 Kyoto Protocol imposed binding emission targets, but only on developed countries. The United States never ratified it, and several others later withdrew or declined to take on new commitments. The 2009 Copenhagen summit ended in disappointment, producing a non-binding accord. Meanwhile, emissions from rapidly industrializing economies such as China and India were rising, and scientific assessments from the Intergovernmental Panel on Climate Change were growing more urgent.
The Paris conference, known as COP21, ran from late November into December 2015 and was hosted by France. Rather than imposing top-down targets, negotiators adopted a bottom-up approach. Each country submitted its own pledge, called a nationally determined contribution, describing how it would curb emissions. The agreement asked countries to update these pledges every five years with the intention of increasing ambition over time, and it created a system of transparency and review. Wealthier nations also reaffirmed a goal of mobilizing climate finance for developing countries, with a figure of 100 billion US dollars per year often cited. The text was adopted by consensus, and it entered into force in November 2016 after enough countries had ratified it.
The agreement's legacy is debated. Supporters credit it with creating a durable common framework, encouraging national climate laws, and sending a signal to investors and industry that the world was moving away from fossil fuels. Critics point out that the pledges are voluntary and that the initial commitments, even if fully met, would fall short of the temperature goals. Analyses since then have generally found that projected warming has been reduced compared with earlier trajectories, but not enough to meet the most ambitious targets.
Politics has also tested the deal. The United States announced its withdrawal in 2017 under President Donald Trump, rejoined in 2021 under President Joe Biden, and later moved to withdraw again. Even so, the agreement has endured as the main arena where governments negotiate how fast, and how fairly, the world should confront climate change.