[1] It was signed in 1992 by 154 states at the United Nations Conference on Environment and Development (UNCED), informally known as the Earth Summit, held in Rio de Janeiro.

It is the "stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic [i.e., human-caused] interference with the climate system".

The Convention was adopted on 9 May 1992 and opened for signature on 4 June 1992 at the United Nations Conference on Environment and Development (UNCED) in Rio de Janeiro (known by its popular title, the Earth Summit).

[16] On 12 June 1992, 154 nations signed the UNFCCC, which upon ratification committed signatories' governments to reduce atmospheric concentrations of greenhouse gases with the goal of "preventing dangerous anthropogenic interference with Earth's climate system".

[20] The ultimate objective of the Framework Convention is specified in Article 2: "stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic [i.e., human-caused] interference with the climate system".

[1] Article 2 of the convention says this "should be achieved within a time-frame sufficient to allow ecosystems to adapt naturally to climate change, to ensure that food production is not threatened and to enable economic development to proceed in a sustainable manner".

[21] The Kyoto Protocol (Japanese: 京都議定書, Hepburn: Kyōto Giteisho) was an international treaty which extended the 1992 United Nations Framework Convention on Climate Change (UNFCCC) that commits state parties to reduce greenhouse gas emissions, based on the scientific consensus that global warming is occurring and that human-made CO2 emissions are driving it.

The Kyoto Protocol applied to the seven greenhouse gases listed in Annex A: carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), sulfur hexafluoride (SF6), nitrogen trifluoride (NF3).

[24] The Protocol was based on the principle of common but differentiated responsibilities: it acknowledged that individual countries have different capabilities in combating climate change, owing to economic development, and therefore placed the obligation to reduce current emissions on developed countries on the basis that they are historically responsible for the current levels of greenhouse gases in the atmosphere.

[36] As part of the Bali Action Plan, adopted in 2007, all developed country Parties have agreed to "quantified emission limitation and reduction objectives, while ensuring the comparability of efforts among them, taking into account differences in their national circumstances".

Considered the world's largest fund of its kind, GCF's objective is to assist developing countries with climate change adaptation and mitigation activities.

These include ongoing questions on how funds will be raised,[58] the role of the private sector,[59] the level of "country ownership" of resources,[60] and the transparency of the Board itself.

The secretariat, augmented through the parallel efforts of the Intergovernmental Panel on Climate Change (IPCC), aims to gain consensus through meetings and the discussion of various strategies.

From 2010 to 2016 the head of the secretariat was Christiana Figueres, following by Patricia Espinosa who was appointed Executive Secretary on 18 May 2016 by United Nations Secretary-General Ban Ki-moon and took office on 18 July 2016.

[66] On 15 August 2022, Secretary-General António Guterres appointed former Grenadian climate minister Simon Stiell as Executive Secretary, replacing Espinosa.

[67] Current and former executive secretaries are: The reports published by IPCC play a key role in the annual climate negotiations held by the UNFCCC.

National Communication reports are often several hundred pages long and cover a country's measures to mitigate greenhouse gas emissions as well as a description of its vulnerabilities and impacts from climate change.

The (Intended) Nationally Determined Contributions (NDCs) that form the basis of the Paris Agreement are shorter and less detailed but also follow a standardized structure and are subject to technical review by experts.

In the aftermath of COP21, these INDCs became Nationally Determined Contributions (NDCs) as each country ratified the Paris Agreement, unless a new NDC was submitted to the UNFCCC at the same time.

[91] The 22nd session of the Conference of the Parties (COP22) in Marrakesh focused on these Nationally Determined Contributions and their implementation, after the Paris Agreement entered into force on 4 November 2016.

An overview is given in the table below:[103] The ultimate objective of the Framework Convention contains some key words that are discussed further below and shown here in italics: "stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic [i.e., human-caused] interference with the climate system".

4 °C warming would lead to significantly increased risks, with potential impacts including widespread loss of biodiversity and reduced global and regional food security.

[109][110][111] In decision making, the precautionary principle is considered when possibly dangerous, irreversible, or catastrophic events are identified, but scientific evaluation of the potential damage is not sufficiently certain.

[citation needed][113] The overall umbrella and processes of the UNFCCC and the adopted Kyoto Protocol have been criticized by some as not having achieved their stated goals of reducing the emission of greenhouse gases.

[117] The perceived lack of progress has also led some countries to seek and focus on alternative high-value activities like the creation of the Climate and Clean Air Coalition to Reduce Short-Lived Climate Pollutants which seeks to regulate short-lived pollutants such as methane, black carbon and hydrofluorocarbons (HFCs), which together are believed to account for up to one third of current global warming but whose regulation is not as fraught with wide economic impacts and opposition.

[118] In 2010, Japan stated that it will not sign up to a second Kyoto term, because it would impose restrictions on it not faced by its main economic competitors, China, India and Indonesia.

[121] These defections place additional pressures on the UNFCCC process that is seen by some as cumbersome and expensive: in the UK alone, the climate change department has taken over 3,000 flights in two years at a cost of over £1,300,000 (British pounds sterling).

[122] Further, the UNFCCC (mainly during the Kyoto protocol) failed to facilitate the transfer of environmentally sound technologies (SETs) which are mechanisms used to decrease the vulnerability of the human race against the unfavorable effects of climate change.

[125] According to the 2020 United Nations Environment Programme (UNEP), with the current climate commitments of the Paris Agreement, global mean temperatures will likely rise by more than 3 °C by the end of the 21st century.

[125] According to the stocktake report, the agreement has a significant effect: while in 2010 the expected temperature rise by 2100 was 3.7–4.8 °C, at COP 27 it was 2.4–2.6 °C and if all countries will fulfill their long-term pledges even 1.7–2.1 °C.