Under the Paris Agreement, all countries share responsibility.
Past climate agreements—most notably the Kyoto Protocol, the most significant climate accord before the Paris Agreement—mandated that countries reduce their emissions by particular standards. It placed the responsibility of climate change—and the obligation to fix it—on developed countries, which historically have emitted the most greenhouse gases. For example, the legally binding Kyoto Protocol initially required the European Union to cut greenhouse gas emissions by 8 percent while not asking for any reduction from dozens of less-developed countries.
But the Paris Agreement revolutionized climate politics by changing the model of negotiations. Now, all countries voluntarily set their goals based on their economic abilities. To achieve this, countries put forward individual plans known as nationally determined contributions (NDCs), which outline their proposed emissions reductions and adaptation strategies.
Unlike previous climate agreements, the Paris Agreement is entirely voluntary. This means that while the agreement requires every country to submit an NDC plan, there are no stipulations as to what ways and by how much countries should cut emissions. Countries’ plans can differ significantly, varying with regard to their specific goals, levels of ambition, and even how they measure emissions cuts.