What was the Kyoto Protocol?

The 1997 Kyoto Protocol is an international agreement on climate change that aimed to reduce greenhouse gas emissions to 5 percent below 1990 levels by 2012. The agreement, which came into force in 2005, required only developed countries, also known as “Annex I” parties, to cut their greenhouse gas emissions and penalized those countries for non-compliance. Developing countries, “non-Annex I” parties, like India and China, though major emitters, were not required to reduce emissions.

The difference in treatment between developed and developing countries was born out of the recognition that industrialized countries are principally responsible for the high levels of greenhouse gases in the atmosphere. On the other hand, small and developing countries—China and India are exceptions—historically have contributed very little to the problem and are least able to adapt to the effects of climate change. Cumulatively over time, the United States has contributed about 25 percent of the world’s greenhouse gas emissions, the most of any single country.

Though President Bill Clinton signed the Kyoto Protocol in 1998, the Senate, in a 95 to 0 vote, passed a resolution declaring that it would not ratify a climate treaty that would “result in serious harm to the U.S. economy” or that had binding greenhouse gas reduction obligations for the United States but not for developing countries. Ratification was required for the treaty to become legally binding on the United States. President George W. Bush ‘unsigned’ the treaty in 2001.

Of the 191 countries that are parties to the Kyoto Protocol, 37 have binding reduction targets. Between 2008 and 2012, those countries reduced emissions over 22 percent compared to 1990 levels, surpassing the agreement’s 5 percent goal. Intended to help countries make emission reductions, the treaty has three market-based mechanisms: a carbon market, and two emission offset programs.

The Kyoto Protocol was born out of the 1992 United Nations Framework Convention on Climate Change (UNFCCC), which was the first, foundational and primary mechanism for the world’s nations to cooperate on climate change. Parties to the UNFCCC, including the United States, meet each year at the “Conference of the Parties” (COP) to discuss how to stabilize greenhouse gas levels in the atmosphere. 

One of the principles underpinning the UNFCCC is that countries have “common but differentiated” responsibilities for addressing climate change since they vary in their contribution to the problem and their capacity to adapt to its effects. The framework is based on scientific evidence showing that human activity has led to increases in atmospheric greenhouse gases which is causing long-term and irreversible effects.

In 2015, another UNFCCC-based treaty was born: the Paris Agreement, which aims to limit global temperature increase to 1.5 degree Celsius above the pre-industrial level. Unlike the Kyoto Protocol, the Paris Agreement does not mandate legally-binding emission cuts and has one reduction framework for all countries, not just developed nations. Every five years parties are required to submit non-binding “Nationally Determined Contributions” with pledges to lower national emissions. The agreement also incorporates the UNFCCC obligation for developed countries to activate public and private financial support for developing countries’ adaptation to climate change effects.

Because the Paris Agreement’s emission reduction commitments are non-binding, the Obama Administration took the position that the Senate did not need to ratify the agreement for the United States to become a party. In 2017, President Donald Trump announced his intent to withdraw from the Paris Agreement effective November 4, 2020. In 2021, President Joe Biden re-joined the agreement.

—Katie Surma

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