Recognizing that the emissions reductions for the Kyoto Protocol were set for a period that would end in 2012, the 2007 UN Climate Change Conference in Bali adopted the "Bali Road Map" as a framework for negotiations over the post-2012 climate regime. In doing so, the parties established two tracks for negotiation: (1) a track by which Kyoto Protocol parties would pursue an amendment to the Protocol for a "second round" of emission targets for Annex I parties, and (2) a track by which UNFCCC parties would seek agreement on GHG mitigation targets or actions for all parties. Non-Annex I parties wishing to associate with the Copenhagen Accord should identify and commit to undertaking "nationally appropriate" GHG "mitigation actions" (NAPAs). Binding and non-binding agreements go by many names, but an agreement is considered binding only if it (1) conveys the intention of its parties to create legally binding relationships under international law and (2) has gone into force. First, the United States must sign the treaty; second, the agreement must be submitted by the Executive to the U.S. Senate for its advice and consent to treaty ratification and two-thirds of the Senators present must give their approval (sometimes inaccurately referred to as "ratification by the Senate" ); and third, the President must ratify the agreement by following the terms of the agreement for ratification or accession. The United Nations Framework Convention on Climate Change (UNFCCC)

The UNFCCC was the first formal international agreement addressing human-driven climate change. The UNFCCC does not set binding targets for GHG emissions. The Committee notes further that a decision by the executive branch to reinterpret the Convention to apply legally binding targets and timetables for reducing emissions of greenhouse gases to the United States would alter the "shared understanding" of the Convention between the Senate and the executive branch and would therefore require the Senate's advice and consent. The George H.W. Amendments, annexes and protocols are to be adopted at ordinary sessions of the Conference of the Parties. The Kyoto Protocol

The Kyoto Protocol was negotiated as a first step towards implementing the UNFCCC, largely by establishing quantitative emission reduction targets for the high income countries listed in its Annex B. The Protocol's goal is to reduce the overall emissions of those parties by at least 5% below 1990 levels by 2012. In 2001, President George W. Bush announced that the United States would not become a party to the Protocol. U.S. law, however, permits some kinds of legally binding international agreements, namely some forms of executive agreements, to avoid taking the form of a treaty. It establishes a process that allows each Annex I party to define its own GHG emissions target level. Consequently, the Accord is not a legally binding international agreement. The United States has submitted a letter to the Executive Secretary indicating its intention to be associated with the Accord, however, because the agreement is not legally binding, this association does not necessarily require U.S. adherence with the Accord's provisions. The Constitution does not appear to require the President to submit the Copenhagen Accord to the Senate for its advice and consent. From the international law perspective then, the Copenhagen Accord is not a treaty. It may be difficult for the United States to achieve its voluntary commitment to reduce its overall greenhouse gas emissions by 17% below 2005 levels by 2020 without congressional support.
The United Nations Framework Convention on Climate Change (UNFCCC) opened for signature in 1992 and soon thereafter was ratified by the United States. The UNFCCC does not set greenhouse gas (GHG) emissions reduction targets, and during ratification hearings, the George H.W. Bush Administration represented that any protocol or amendment to the UNFCCC creating binding GHG emissions targets would be submitted to the Senate for its advice and consent.
The Kyoto Protocol (the Protocol) to the UNFCCC was intended as a first step towards implementing the UNFCCC. To that end, it sets quantitative emission reduction targets for the high income countries listed in its Annex B. The Protocol's goal is to reduce each parties' overall emissions by at least 5% below 1990 levels by 2012. Although the United States signed the Protocol in 1998, it did not submit the Protocol to the Senate. The George W. Bush Administration announced in 2001 that it would not pursue U.S. accession to the Protocol. The Obama Administration has followed this policy.
In 2007, the UN Climate Change Conference in Bali adopted a framework for negotiations over the post-2012 climate regime. It established two tracks for negotiation: (1) a track by which Kyoto Protocol parties would pursue an amendment to the Protocol for a "second round" of emission targets for its Annex B parties, and (2) a track by which UNFCCC parties would set GHG mitigation targets or actions for all parties. However, consensus under either track proved difficult to achieve at the 2009 Copenhagen Conference of the Parties. The outcome, the Copenhagen Accord (the Accord), is consequently considered a non-binding political agreement. The Accord allows each high income party listed in Annex I of the UNFCCC to define its own GHG emissions target level. "Non-Annex I" parties wishing to associate with the Accord must identify and commit to undertaking "nationally appropriate mitigation actions," which may receive international support subject to certain international reporting requirements.
The labels "convention," "protocol," and "accord" are not clear indicators of whether these three climate change agreements are binding internationally and/or domestically. Under international law, an agreement is considered binding only if it conveys the intention of its parties to create legally binding relationships and has entered into force. However, some have suggested that enforceability, rather than intentions, should govern whether an agreement is "legally binding."
Under U.S. law, a legally binding international agreement may take the form of a treaty or an executive agreement. In order for the United States to enter a treaty, the agreement must be approved by a two-thirds majority of the Senate and subsequently be ratified by the President. An executive agreement does not require the Senate's advice and consent in order to be legally binding. Historically, executive agreements have arisen in a limited set of circumstances, and certain subjects, including significant global environmental issues, have traditionally been handled as treaties that require the Senate's approval.
Of the three agreements discussed, only the UNFCCC and the Kyoto Protocol are considered legally binding agreements under international law, and the United States is bound only by the former. The United States has, however, indicated its intent to associate with the Copenhagen Accord. In doing so, it voluntarily committed to reduce U.S. emissions by 17% below 2005 levels by 2020. The Accord does not implicate the treaty power of Congress, which will likely shape the domestic effect of the Copenhagen Accord through appropriations and lawmaking. The Accord does not appear to empower the Executive to implement it solely by agency actions.