International responses

Kyoto Protocol (1997)

The Kyoto Protocol, negotiated under the UN Framework Convention on Climate Change, set binding emissions reduction targets for developed countries. It came into force in 2005. The United States never ratified the protocol, weakening its effect. Developing countries (including China and India) were exempt from binding limits, a feature that became increasingly problematic as Chinese emissions grew.

Paris Agreement (2015)

The Paris Agreement, signed by nearly every country, established a framework in which each country sets its own emissions reduction targets (Nationally Determined Contributions). The agreement's headline goal is to limit warming to well below 2°C above pre-industrial levels, with a more ambitious aim of 1.5°C. Critics note that the targets countries have set are not collectively sufficient to meet these goals and that the targets are not binding. The United States withdrew from the agreement under President Trump in 2017, rejoined under President Biden in 2021. As of the early 2020s, the world is on track for warming substantially above 1.5°C.