Kyoto Protocol Adopted
The Kyoto Protocol was adopted, the first international treaty binding countries to cut greenhouse gas emissions
December 11, 1997
The First Binding Climate Deal
On December 11, 1997, more than 150 countries adopted the Kyoto Protocol in Kyoto, Japan — the first international treaty to set legally binding targets for reducing greenhouse gas emissions. The agreement required industrialized nations to cut their combined emissions of six greenhouse gases by an average of 5.2 percent below 1990 levels during the period 2008 to 2012. It was a historic step: for the first time, the world's wealthiest countries were legally obligated to take measurable action on climate change. The treaty came into force in February 2005, after Russia's ratification gave it the required number of signatories.
Who Was In, Who Was Out
The Kyoto Protocol made an important distinction between developed and developing countries. Wealthy industrialized nations — which had produced most of the greenhouse gases already in the atmosphere — were required to meet binding emission targets. Developing countries, including China and India, were not. This approach reflected the principle of "common but differentiated responsibilities." The United States, the world's largest economy and at the time its largest emitter, signed the protocol under President Clinton but never ratified it. The Senate voted 95-0 against ratification, arguing it was unfair to exempt developing nations. Canada withdrew in 2011, having no realistic chance of meeting its targets.
A Flawed but Foundational Treaty
The Kyoto Protocol had significant weaknesses. The absence of the United States and the exclusion of major developing-country emitters limited its impact. Some countries that did participate failed to meet their targets. Yet the protocol established important infrastructure for international climate diplomacy: monitoring systems, carbon markets, and the principle that global warming was a shared global responsibility requiring a coordinated global response. It paved the way for the Paris Agreement in 2015, which took a broader approach and brought more countries to the table.