The Kyoto Protocol can be defined as the implementation of the UNFCCC. At the time, it was the first global commitment to govern emissions responsible for global warming and laid the groundwork for subsequent international agreements on climate change. Although the protocol was signed on March 16, 1998, it did not come into force until February 16, 2005. The Kyoto Protocol is an international agreement on climate change developed under the United Nations Framework Convention on Climate Change (UNFCCC). The protocol encourages 192 parties to reduce their greenhouse gas emissions, with many industrialized countries having binding emission reduction targets. As part of this debate, important climate agreements have developed in the pursuit of emissions reductions. The Kyoto Protocol only required industrialized countries to reduce their emissions, while the Paris Agreement recognized that climate change was a common problem and called on all countries to set emission targets. If airlines release more than the capped amount, they must purchase emission reduction credits. CORSIA is divided into two phases: the first phase from 2021 to 2027 is voluntary, while phase two, which will begin in 2028, is mandatory and will take place in 2035. At the time of publication, 65 states, representing more than 86.5% of international aviation activity, stated that they were willing to participate voluntarily in Phase 1 of CORSIA. If full compliance is achieved, the Environmental Defence Fund estimates that greenhouse gas emissions would be reduced by 2.5 billion tonnes, or an annual reduction of 35 million cars for the longevity of the agreement.

The United Nations Conference on Environment and Development, held in Rio de Janeiro in 1992, has affected international consensus on the issue of climate change. During the summit, the United Nations Framework Convention on Climate Change (UNFCCC) was established, which was originally signed by 166 countries and finally entered into force on 21 March 1994. To date, it has been ratified by 197 countries. The protocol recognizes that industrialized countries are the main culprits for high levels of greenhouse gas emissions into the atmosphere, following more than 150 years of industrial activity, and represents a greater burden for industrialized countries to reduce emissions. 191 countries approved the treaty. The Montreal Protocol on ozone-depleting gases does not directly address climate change, but ozone-depleting gases contribute to global warming. The 1987 Montreal Protocol requires 196 nations to reduce ozone-depleting gas emissions, often used in refrigerators, foams and industrial applications. These gases dilute the ozone layer, so that more ultraviolet (UV) light can pass through the atmosphere. Increased exposure to UV light is associated with an increase in skin cancer. Kyoto Protocol, 2005. The Kyoto Protocol [PDF], adopted in 1997 and entered into force in 2005, was the first legally binding climate treaty.

It called on industrialized countries to reduce emissions by an average of 5% from 1990 levels and set up a system to monitor countries` progress.