For the Kyoto Protocol to enter into force, at least 55 parties to the Framework Convention on Climate Change, together accounting for at least 55 percent of total CO2 emissions produced by developed countries in 1990, had to ratify it.
The Kyoto Protocol entered into force in 2005 after ratification by Russia, which was responsible for around 16 percent of said emissions. By ratifying the Kyoto Protocol, developed countries made a binding commitment to reducing their emissions of the key greenhouse gases - including carbon dioxide (CO2), methane (CH4) and laughing gas (N2O). The Protocol lays down individual provisions for each country that have to be implemented within so-called commitment periods. To achieve this, a number of flexible mechanisms (the Kyoto mechanisms) are available to the countries to supplement reductions in their domestic emissions.
The 1997 Climate Change Conference in Kyoto did not specify details of the mechanisms or the Protocol. These details were clarified during subsequent climate change conferences. The conference in Marrakesh in 2001 (COP7) played a crucial role in this context. Detailed provisions were adopted in the Marrakesh Accords on the use of the Kyoto mechanisms, crediting sinks, in other words the natural storage of carbon dioxide in forests, soils and oceans, and promoting climate action in developing countries.