Members of Congress hold diverse views about the value of international cooperation to address climate change. While some Members are convinced that human-induced climate change is a high priority risk that must be addressed through federal actions and international cooperation, others are not convinced of significant risk. Some are wary, as well, of international processes that could impose costs on the United States, undermine national sovereignty, or lead to trade advantages for other countries. The United States government has participated for more than two decades in various multilateral negotiations and actions aimed at addressing climate change. This report surveys the United Nations negotiations, from a primarily U.S. perspective. A table at the end of the report summarizes the chronology ( Table 1 ). Formal international negotiations were launched in December 1990 to address growing scientific and political concern about human-induced climate change. The negotiations on the 1992 United Nations Framework Convention on Climate Change (UNFCCC) marked the progress of decades of scientific research. Scientific conclusions—with uncertainties—have remained stable over two decades: greenhouse gas (GHG) emissions from human-related activities are very likely causing the major portion of climate change observed in recent decades. If changes continue, they could lead to adverse impacts on human societies and their environment, potentially including catastrophes. Predicting the timing, magnitude, and implications of change remains imprecise; many uncertainties may not be resolvable in a time frame consistent with making effective and efficient decisions to reduce the risks of climate change. The question of how to share any effort to address climate change has been a core challenge for international cooperation. Because emissions come from all countries, only concerted reductions by all major emitters can stabilize the rising GHG concentrations in the atmosphere. The United States historically has contributed the most—almost one-fifth of the rise of GHG concentrations since the Industrial Revolution. In 2007, however, China surpassed the United States as the leading emitter of GHG annually. In the future, the greatest growth in GHG emissions is expected from industrializing countries, such as China, India, and Brazil. These countries historically have contributed less, and still emit much less per person, than the United States and most other high-income countries. Arguably, the least developed and still industrializing nations have lower economic and governance capacities to address the problem. The size of effort and how to allocate it is a key element of negotiations. The primary issues for negotiation in 1990 remain the same today: when and by how much to reduce greenhouse gas emissions globally in order to achieve the UNFCCC's objective of avoiding " dangerous anthropogenic interference with the climate system "; how to share " common but differentiated responsibilities " among countries taking into account " historic contributions " and " respective capacities " of different people—in particular, the acceptable degree of participation of low-income countries; what mechanisms are best suited to assuring GHG reductions at the lowest cost, respecting national sovereignty and supporting " sustainable economic development " and " the eradication of poverty "; how cooperatively to understand the risks and facilitate adaptation to climate changes, especially by those people least able to cope on their own; and how to adapt international arrangements over time as science, social conditions, and capabilities evolve. At present, the United States is one of three of the 194 Parties to the UNFCCC that is not also Party also to the subsidiary Kyoto Protocol. (The other two are Canada and Andorra.) As a Party to the UNFCCC, the United States has general obligations to reduce its GHG emissions, report its emissions and be subject to international review, and assist lower-income countries, and other binding commitments. The industrialized Parties to the Kyoto Protocol ( Annex I Parties ), however, took on binding, quantitative commitments to reduce their GHG emissions to 5% below 1990 levels during 2008-2012 and agreed in 2012 to reduce these further during a second commitment period from 2013 to 2020. Most Parties have made voluntary pledges to GHG reduction targets or nationally appropriate mitigation actions under the 2009 Copenhagen Accord and the 2010 Cancun Agreements. Nonetheless, many non-Annex I Parties have opposed taking on legally binding commitments to abate GHG emissions. Many Annex I Parties have opposed taking on further legally binding commitments without participation by all Parties. The 2011 Durban Platform envisioned an end to two-track (developed versus developing) negotiations and provided a mandate to negotiate by 2015 a single outcome "with legal force" applicable to all Parties and that would take effect after 2020. How to pay for GHG reductions and adaptation measures is another key issue. The wealthiest Parties (including the United States) pledged "fast start" financing approaching $30 billion during 2010-2012, and a goal of mobilizing financing of $100 billion annually by 2020. Funding will come from public and private, bilateral and multilateral, and alternative sources. The most vulnerable developing countries had priority for the 2010-2012 funds. Reportedly, the fast-start financing goal was exceeded, but the pathway to meeting the 2020 pledge remains obscure. This report summarizes the process and principle issues and outcomes of the international climate change negotiations since 1990. Further, CRS has produced a series of reports on many aspects of the international climate change negotiations (and domestic issues) that can be accessed through the CRS website ( http://www.crs.gov/Pages/clis.aspx?cliid=2522 ) or by contacting CRS Inquiry at [phone number scrubbed]. This report summarizes the principal events and agreements, followed by a chronology at the end. The international negotiations launched in 1990 culminated in the 1992 adoption of the United Nations Framework Convention on Climate Change (UNFCCC) in Rio de Janeiro, Brazil. The U.S. Senate quickly gave its advice and consent, leading the United States to be the fourth nation to ratify the UNFCCC—the first among industrialized countries. As of November 1, 2013 195 governments were Parties to the UNFCCC. As a framework convention, this treaty provides the structure for collaboration and evolution of efforts over decades, as well as the first qualitative step in that collaboration. The UNFCCC does not, however, include measurable and enforceable objectives and commitments. The UNFCCC originally listed 35 of the most industrialized nations (including the United States) plus the European Economic Community (now the European Union, or EU) in Annex I. These Annex I Parties accepted specific commitments, particularly to take the lead in adopting national policies and undertaking measures with an aim to reduce human-related greenhouse gas (GHG) emissions to their 1990 levels by the year 2000. Annex I Parties also agreed to submit inventories of their emissions and sinks , and national communications of their UNFCCC-related policies and actions. The non-Annex I Parties were then low-income countries, though many are now middle- or high-income countries (e.g., Singapore). The UNFCCC also listed in Annex II the then-wealthiest Parties (including the United States), which committed to providing agreed new and additional financial resources to assist the developing country Parties to meet their obligations. By the time the treaty entered into force and the Conference of the Parties (COP) met for the first time in 1995, the Parties agreed that achieving the objective of the UNFCCC would require further, stronger, and binding GHG commitments. The 1995 Berlin Mandate for negotiations on a 1997 protocol deferred any new commitments for developing countries to later agreements. As a first enforceable step toward meeting the objective of the UNFCCC, the 1997 Kyoto Protocol promised to reduce the net GHG emissions of industrialized country Parties (Annex I Parties) to 5.2% below 1990 levels in the first commitment period of 2008 to 2012. It also pledged to assess the adequacy of these commitments early in the new century. The United States signed the Kyoto Protocol on November 12, 1998. In Congress, however, opposition was strong. In the "Byrd-Hagel" Resolution in July 1997, the Senate expressed its opposition (95-0 vote) to the terms of the Berlin Mandate, by stating that the U.S. should not sign any treaty that does not include specific, scheduled commitments of non-Annex I Parties in the same compliance period as Annex I Parties, or that might seriously harm the U.S. economy. The Kyoto Protocol (KP) was not submitted to the Senate for ratification by President Clinton, nor by his successor, President George W. Bush. Newly elected President Bush announced in 2001 that the United States would not become a Party because the Kyoto Protocol did not include GHG commitments by other large emitting non-Annex I countries and because of his conclusion that it would cause serious harm to the U.S. economy. As of November 1, 2012, 192 governments were Parties to the Kyoto Protocol. The United States and Andorra are the only Party to the UNFCCC never to join the Kyoto Protocol, while Canada withdrew from it in December 2012. Negotiations following the Kyoto Protocol particularly contested differentiation of commitments and assistance to developing countries, and slowed agreement on further steps under the UNFCCC. In 2007, Parties agreed to establish two tracks for negotiation of further commitments of Parties, one under the Kyoto Protocol and the other under the UNFCCC. The first track was a mandate among the Kyoto Protocol Parties (not including the United States) to pursue an amendment to the Protocol on further commitments of Annex I Parties for the period(s) beyond the year 2012. The first commitment period runs from 2008 through 2012. The second track was established in December 2007, when the Conference of the Parties (COP) to the UNFCCC agreed to a "Bali Action Plan" to negotiate new GHG mitigation targets for Annex I Parties, "nationally appropriate mitigation actions" for non-Annex I Parties, and other commitments for the post-2012 period. The mandates specified that the products of negotiation should be ready by the end of 2009, for decision at the 15 th meeting of the COP and the fifth Meeting of the Parties to the Kyoto Protocol (CMP, or sometimes COP/MOP), in Copenhagen, Denmark. The form(s) of agreement were not clear, nor how the two negotiating tracks might converge. (As discussed later, the Durban Platform of 2011 established a mandate that ended the Bali Action Plan, with negotiations that proceed on one track applicable to all Parties.) The Bali Action Plan framed the key items for the "Copenhagen" negotiations to address climate change beyond 2012 as mitigation of climate change (primarily to reduce GHG emissions or to enhance removals of carbon by forests and other vegetation "sinks"); adaptation to impacts of climate change; financial assistance to low-income countries; technology development and transfer; and a shared vision for long-term goals and action. In addition, provisions for "monitoring, reporting, and verification" (MRV) permeated the negotiations. Provisions to reduce GHG emissions from deforestation and forest degradation ("REDD+") were also pursued under the Bali Action Plan. While the inter-sessional meetings during 2008 and 2009 showed little movement, public and many diplomatic expectations were high that the United States, and perhaps China and other developing countries, would come to the Copenhagen negotiations with a new willingness to change positions and agree to (1) a second commitment period of the Kyoto Protocol with GHG targets for Annex I Parties and (2) a new instrument that would include quantitative GHG commitments for the United States and perhaps an array of non-Annex I Parties or all Parties. Many experts and stakeholders around the world opined that the Copenhagen sessions in December 2009 failed, bringing the United Nations' process close to collapse; others judged the meetings differently. Certainly, the Copenhagen meetings did not meet the very high expectations set by the UNFCCC Secretariat and many advocates of commitments to aggressive GHG emissions mitigation by either the Annex I or all Parties. There were practical outcomes of the Copenhagen negotiations nonetheless; these included evolving recognition of the political and economic barriers in some countries to setting aggressive international obligations that Parties are not sure to fulfill. Another was a greater focus on transparency through enhanced reporting and verification of actions in countries. The U.S. Deputy Envoy for Climate Change, Jonathan Pershing, called the Copenhagen Accord a "paradigm shift" in the long-term path of the UNFCCC negotiations, from a "top-down" assignment of GHG targets to Parties to a "country-up" offering of commitments. The Copenhagen negotiations revealed distance among many countries' "bottom lines," without ground of consensus on major issues, such as the form and structure of agreements; obligations for GHG reductions and actions; the legal nature of future commitments; and acceptable provisions for monitoring, reporting, and verification (MRV). A "Copenhagen Accord" emerged that bridged some difficult differences and identified a common and differentiated path forward. While most UNFCCC Parties seemed willing to adopt the Copenhagen Accord, it was blocked by Bolivia, Cuba, Sudan, and Venezuela, arguing that the closed-door deal-making violated the procedures of the United Nations Charter. Tuvalu and some other nations rejected the agreement for not assuring, in their views, sufficiently deep GHG reductions. Consequently, the COP only "took note" of the text, but did not adopt it. Hence, the Copenhagen Accord was a political outcome, not a legal agreement. The Copenhagen Accord outlines a number of key points for action on mitigation, adaptation, financing, technology, reducing emissions from deforestation, and a long-term vision of avoiding temperature increases. All of these elements have been embodied in the Cancun Agreements of December 2010 (see next section). The Copenhagen Accord also included a pledge by the wealthiest Parties to arrange "fast start" financing approaching $30 billion during 2010-2012, and a goal of mobilizing financing of $100 billion annually by 2020. Funding will come from public and private, bilateral and multilateral, and alternative sources. The most vulnerable developing countries have priority for the 2010-2012 funds. These financial pledges carried into the Cancun Agreements as well. The Copenhagen Accord seemed a weak but generally agreed instrument. Following the terms of the pact, by the end of 2010, 114 Parties to the UNFCCC had associated themselves with the Copenhagen Accord, and 42 Annex I Parties and EU Member States had submitted quantified economy-wide emissions targets for 2020. Thirty-five non-Annex I Parties submitted nationally appropriate mitigation actions (NAMAs). Another 42 non-Annex I Parties associated themselves formally with the Accord (and were listed in the Accord as such). Some of those that submitted actions or targets did not associate with the Accord. Cuba, the Cook Islands, Ecuador, Kuwait, and Nauru formally notified the UNFCCC Secretariat that they would not associate or engage with the Accord. Meetings in 2010 suggested that some Parties might retreat from pledges made in the Copenhagen Accord. Notably, several low-income countries reemphasized the two-track, pre-Copenhagen texts from the 2007 Bali meetings, rather than the single text of the Copenhagen Accord. Nevertheless, the government of Mexico, as host of the December 2010 meeting in Cancun, facilitated inclusive and transparent deliberations, restoring the confidence of some Parties in the negotiations process, and which yielded several decisions of the Parties collectively called the "Cancun Agreements" (CA). To a large degree, the Cancun Agreements reiterated elements already included in the UNFCCC, the Bali Action Plan, and the Copenhagen Accord. The Cancun Agreements continued the two tracks of negotiations toward post-2012 commitments. However, they contained nearly identical language on key points in the separate decisions under the UNFCCC and the Kyoto Protocol. A few paragraphs established explicit formal linkages between the two negotiating tracks. Major elements of the Cancun Agreements included the following: Long-term vision for GHG mitigation: (Only in the decision directly under the UNFCCC.) Identifies a wide variety of elements that are components of the long-term package considered necessary to address the multiple faces of climate change. States that "deep cuts" in global emissions are required "with a view to ... hold the increase in global average temperature below 2 o C." Also, establishes consideration beginning in 2013 of setting a more stringent goal to avoid a temperature increase exceeding 1.5 o C. A Cancun Adaptation Framework and an Adaptation Committee: Both established to promote national adaptation plans; and to prioritize and strengthen institutional capacities and disaster risk reduction strategies, research and technology development, and other country-driven actions to build social and ecological resilience to climate change. The work program may consider options for risk management, including development of a climate risk insurance facility. Parallel GHG mitigation by Annex I and non-Annex I Parties: Notes GHG mitigation targets for 2020 reported by Annex I Parties, and nationally appropriate mitigation actions (NAMAs) to be implemented by Non-Annex I Parties and communicated to the Secretariat by them, compiled in public documents to be issued by the Secretariat. Further reporting and analysis will clarify the assumptions and implications for the reported targets and actions. A registry on NAMAs: To record and update information on actions for which countries are seeking support; support available for NAMAs; and support provided for NAMAs. Enhanced reporting by Annex I Parties and international assessment: Requires reporting of emissions and removals related to GHG commitments, and to financial, technology, and capacity-building support provided by them. Transparent reporting and international review of Non-Annex I Parties' mitigation while respecting national sovereignty: Non-Annex I Parties must submit National Communications every four years, with biennial updates to include national GHG inventories and mitigation actions, needs, and support received. Domestic actions will be subject to domestic monitoring, reporting, and verification (MRV) in accordance with future guidelines. A process for international consultations and analysis (ICA) of biennial reports will be non-intrusive, non-punitive, and respectful of national sovereignty. Mitigation actions (as well as technology, financing, and capacity-building) supported by international finance will be subject to international MRV. Reducing Emissions from Deforestation: Requests countries to reduce carbon losses from land uses, including REDD+, and to enable mobilization of supportive international financing. Requests the AWG-LCA to explore financing mechanisms for implementing "results-based actions" to reduce emissions from deforestation and forest degradation, conserve and enhance forest carbon stocks, and to manage forests sustainably. With provision of adequate and predictable support, developing countries would develop forest and carbon reference levels and transparent national forest plans and safeguards monitoring systems. "Results-based actions" should be "fully measured, reported, and verified." Consideration of market-based mechanisms: Permits further consideration of emissions trading to assist developed country Parties to meet part of their GHG commitments, to supplement their domestic actions, to maintain and build on those under the Kyoto Protocol. A commitment by developed countries to mobilize finance for adaptation, mitigation, technology, and capacity-building: Pledges approaching $30 billion during 2010-2012, and a goal of $100 billion annually by 2020. Funding will come from public and private, bilateral and multilateral, and alternative sources. The most vulnerable developing countries had priority for the 2010-2012 funds. A Green Climate Fund (GCF): The GCF is governed by a board of 24 representatives, equally from developed and developing countries, to channel a significant share of new multilateral funding for adaptation and mitigation. The GCF is accountable to the COP, and is assisted by a new Standing Finance Committee. A Trustee (for at least three years the World Bank), accountable to the GCF Board, manages the financial assets, maintains records and prepares statements according to fiduciary standards. A Technology Mechanism: To support actions on mitigation and adaptation, accountable to the COP, composed of a standing, expert Technology Executive Committee and a Climate Technology Center (CTC) and Network. The CTC is intended to facilitate assistance by the Network at the request of a developing country Party. Intellectual property controversies are not addressed. Review by the COP of the long-term global goal: Starting by 2013 and ending by 2015, to lead to "appropriate action based on the review." The Decision of the Parties to the Kyoto Protocol took note of the GHG reduction pledges of the Annex I Parties in accordance with the Copenhagen Accord. The Decision under the Kyoto Protocol did not set a new deadline to conclude extension of the Protocol, only agreeing that it should be "as early as possible and in time to ensure that there is no gap between the first and second commitments periods." Japan, Canada, and others announced that they would not participate in an extension of the Kyoto Protocol, and that they would consider only an agreement that includes GHG mitigation requirements of all major emitters (including the United States). The absence of commitments from the top three global GHG emitters (China, the United States, and India) was a matter of consternation among many delegations and stakeholders. The Cancun Agreements marked a tentatively renewed confidence of many in the United Nations process. Many, though, watched the development of rules and guidelines, and degree of follow-through by countries on their pledges, as measures of success of the global process. Many, simultaneously, turned toward other domestic, bilateral, and multilateral institutions and processes, such as the development banks, the Major Economies Meetings, and private fora, as possibly more effective supplements or alternatives to the UNFCCC processes. Additionally, the experiences of the Copenhagen and Cancun processes, and their outcomes, marked an increase in attention to national and sub-national efforts to address climate change, relative to the attention and credence given to international negotiations. Among the decisions made by Parties at COP 17 in Durban, South Africa were two of particular note: (1) an agreement to a second commitment period (CP2) of the Kyoto Protocol, and (2) a mandate, the Durban Platform for Enhanced Action (DP), to negotiate by 2015 a new agreement "with legal force" that would be "applicable to all Parties", to begin implementation after 2020. Agreement on a new commitment period for GHG abatement under the Kyoto Protocol proved key to gaining consensus on the Durban Platform. Notably, delegations from China, India, and some other middle-income countries insisted that the highest-income Annex I Parties must meet their existing GHG reduction obligations and sign up to further reductions under the Kyoto Protocol. They also sought continuation of the Clean Development Mechanism of the Kyoto Protocol, through which non-Annex I Parties could sell GHG reduction credits. On the other hand, Canada, Japan, and Russia stated they would only consider an agreement that includes GHG reduction commitments from all major emitters (i.e., including China, the United States, and others). The EU, ultimately pivotal in the compromise, agreed to a second commitment period of the Kyoto Protocol only in conjunction with a decision to set out a clear roadmap to a new agreement that would include legally binding GHG reductions for all major emitters. In concept, the Durban Platform mandate could eliminate after 2020 the bifurcation of countries into "developed" or "developing." It remains to be seen whether Parties will adopt new approaches or fall back on positions that have been in stalemate for many years. Following up on other aspects of the Cancun Agreements, Parties also decided on the governing instrument for the Green Climate Fund (launched in 2012) to help finance mitigation and adaptation measures in low-income countries; a technology expert panel, modalities of the Technology Executive Committee, and criteria and a process for selecting the host of the new Climate Technology Centre—the center of a global network of technology centers; methods to establish reference levels against which to measure avoided deforestation as a basis for market payments, rules to count reductions from peatlands, and languages on reporting safeguards for indigenous people and other concerns with REDD+ projects; and guidelines for biennial reports by Parties, procedures for "international assessment and review," "international consultation and analysis," and other actions to increase the transparency of countries' emissions-cutting actions. The 18 th session of the COP and the 8 th Session of the CMP produced a set of decisions collectively dubbed the Doha Climate Gateway . The agreements formally closed processes under the Bali Action Plan (2007), such as the Ad Hoc Working Group on Long-Term Cooperation (AWG-LCA) and the Ad Hoc Working Group on the Kyoto Protocol (AWG-KP). These processes have given way to new paths forward focused 1. under the UNFCCC, on a. implementation of past agreements, and b. the search for a future accord to be hammered out by the Ad Hoc Working Group on the Durban Platform for Enhanced Action (ADP); 2. under the Kyoto Protocol, on adoption of the Doha Amendment, which established a second commitment period for GHG targets from 2013-2020, covering 37 countries and the European Union, and requiring reductions of GHG emissions to, on average, 18% below 1990 levels. These are detailed below. In addition, the Parties to the UNFCCC continue to operate without rules on voting. As a result, decisions must be made by consensus (without objection). This is increasing seen by some as a problem for further progress under the UNFCCC, as any one Party may block an agreement. For the second time in UNFCCC history, the Chair gaveled adoption of a decision over the objections of a Party (see Bolivia's experience in discussion of the Cancun Agreements ). The Chair announced adoption of the Doha Amendment with language restricting sales of surplus AAUs over a delegation trying to object. This incident has raised questions about whether and how voting and consensus may evolve. Past meetings produced many decisions and agreements to analyze issues, produce plans, establish institutions, and other activities generally aimed at reducing GHG emissions, including from deforestation, forest degradation, and other activities. Themes of deliberations to reduce GHG emissions include Closing the "gap" between current pledges and the maximum 2 o C vision : Beyond urging countries to increase their ambition, much of the work is to clarify GHG pledges and compare them, with an eye toward encouraging all Parties to take on "comparable" efforts. Under the 2010 Cancun Agreements, more than 85 Parties—both Annex I and non-Annex 1(including China, India, Indonesia, Mexico, and many others)—made non-binding pledges to abate national GHG emissions. These pledges are stated with different base years, scopes, and other conditions that make comparison and evaluation challenging. Work continues on "clarification," "common elements", "comparability", and assistance to developing countries in making pledges. Supporting mitigation and adaptation actions by developing countries : Many non-Annex I Parties are working on low-carbon development strategies and Nationally Appropriate Mitigation Actions (NAMAs) that address multiple policy objectives in GHG mitigation, energy supply, water management, provisions of sanitation, and social development. Work continues to prepare and carry out NAMAs, and to match these efforts to technical, financial, and capacity-building support. The work program on Reducing Emissions from Deforestation and Forest Degradation, plus Conservation (REDD+) continues to struggle with questions about how to verify and validate GHG reductions. The COP in Doha extended the work program on long-term finance for an additional year. Discussion of a "mid-term gap" from 2012 to 2020, from the end of fast-start financing to the 2020 named in the $100 billion pledge, led to a decision encouraging developed countries to increase efforts to provide finance from 2013 to 2015. The Standing Committee on Finance (SC) was charged with identifying options to mobilize financial resources that are adequate, predictable, sustainable, and accessible. Industrialized countries were urged to "provide resources of at least to the average annual level of the fast-start period for 2013-15." Denmark, France, Germany, Sweden, the United Kingdom, and the EU Commission pledged as much as $8.5 billion for the period to 2015. The SC reported that developed countries had delivered more than $33 billion in fast-start climate finance between 2010 and 2012. This was greater than the pledge for $30 billion in fast-start finance they made in Copenhagen in 2009. Many Parties and observers questioned, however, whether all the financing counted is "new and additional" or recounted financing that would have been available anyway. The SC will continue to debate proposals for taxes on international aviation, international shipping, and/or international financial transactions as possible, more reliable sources of funding than periodic, voluntary replenishments from public coffers. The SC will also prepare biennial reports assessing financial flows, and developing methods for improved reporting of financial flows. The Green Climate Fund (GCF) moved forward. The COP agreed to a governing instrument for the Green Climate Fund (GCF) but some Parties and stakeholders expressed disappointment that more progress had not been made in operationalizing the GCF. They also sought more clarity on how much money will be available in the GCF, the role of the private sector, and the balance of mitigation and adaptation pay-outs. Parties selected Songdo, South Korea, as the host of the GCF. Considerable discussion revolved around the relationship between the Governing Board and the COP. Parties continued to discuss the roles and linkages between the Technology Executive Committee (TEC) and the Climate Technology Centre and Network (CTCN), both established in the Cancun Agreements . Parties continued to disagree on whether intellectual property rights should be discussed in the TEC, given that they are covered in fora other than the UNFCCC. Parties agreed to meetings to support two "workstreams" of the ADP, relating to 1. the 2015 agreement, to take effect in 2020; and 2. "pre-2020 ambition"—or increasing the reduction of GHG emissions in the period to 2020. "Balance" has become a key concept, concerning relative priorities between the two workstreams, and among the subjects of adaptation, "enhanced ambition" in GHG mitigation, means of implementation (finance, technology development and transfer, and capacity-building), and transparency of actions and support for actions. Decisions in Doha included several further items: Parties agreed to consider managing Loss and Damage through an institutional mechanism. Some characterize this as agreement to a process to address "loss and damage" while the United States does not contemplate participating in any arrangement based on blame or liability for past actions, including GHG emissions. Parties agreed to consider the possible roles of both market mechanisms and non-market mechanisms in the new 2015 agreement. At the request of Saudi Arabia, Parties agreed to work to consider diversification of economies, suggesting a vision beyond reliance primarily on production of fossil energy. The Doha Amendment to the Kyoto Protocol established the second commitment period, from 2013-2020 for the Kyoto Protocol, with GHG targets for 37 countries plus the EU averaging a reduction of 18% below 1990 levels. Japan, New Zealand, and the Russia Federal declined new GHG targets because all major emitters did not participate. Canada formally withdrew from the Kyoto Protocol. Because some Parties were disappointed with what they considered to be a low level of ambition for GHG reductions in the second commitment period, the Doha Amendment provided for a voluntary review in 2014 of Annex I Parties' Quantified Emission Limitations and Reduction Commitments (QELRCs) . The first commitment period of the KP, in 1997, covered more than 55% of the 1990 "basket of six" GHG emissions globally. The second commitment period covers approximately 15%, given the growth of emissions by a number of non-Annex I countries and without the participation in second commitment period GHG targets by the Russian Federation, Japan, and New Zealand, the United States, or Canada. The Doha Amendment modified several rules for the KP's second commitment period: Only Annex I Parties taking on GHG targets in the second commitment period may transfer and acquire emission reduction credits from the Clean Development Mechanism (CDM) and Joint Implementation, two of the three flexibility mechanisms under the Kyoto Protocol. Parties that have not used all their Assigned Allowance Units ( AAUs) from the first commitment period may sell to other Parties. Nonetheless, the EU, Japan, and other countries vowed they would not acquire any, as they do not consider that the "surplus" AAUs represent real GHG emission reductions. Disagreement continued over whether AAUs unused in the first or second commitment periods should be cancelled from 2020. Some observers have noted vagaries in the text that may create uncertainties in the likely size of credit supplies and market demand under the market mechanisms. Members of Congress may seek to monitor and provide input to the Doha Platform (ADP) negotiations, due to reach an agreement in 2015 to take effect in 2020, with a vision of avoiding a 2 o C (3.6 o F) increase of global average temperature above pre-industrial levels. The United States will be among the countries under most pressure also to provide financial and other assistance to low-income countries, to help them take on and adhere to commitments to GHG mitigation and adaptation. In preparation for the 2015 ADP negotiations, Congress may wish to provide advice regarding the United States' position at summit of world leaders, to be convened by UN Secretary General Ban Ki-Moon in September 2014; he has challenged leaders to bring "bold pledges." Members of Congress hold divergent views about the value of international cooperation to address climate change. While some Members are convinced that human-induced climate change is a high priority risk that must be addressed through federal actions and international cooperation, others are not convinced of significant risk. Some are wary, as well, of international processes that could impose costs on the United States, undermine national sovereignty, or lead to trade advantages for other countries. Regardless of current views, the United States is a Party to the UNFCCC and has certain obligations, however unenforceable, under that treaty. The United States' behaviors in that context are likely to continue to draw great attention on the world stage. Arguably, U.S. credibility is impaired to the degree that it has not followed through on earlier commitments, is unable to negotiate for unambiguous commitments due to lack of domestic consensus, and cannot assure others that any agreements made by an Administration would be accepted by Congress. The Executive Branch continues international negotiations and implementation of the UNFCCC obligations. Committees of Congress engage in oversight (from home and at the international meetings), providing input to the Administration formally and informally, and deciding program authorities and appropriations for these activities. Given the continuing public and legislative debate over whether and how to address climate change, the 113 th Congress may engage on the international aspects. International cooperation would be required to curtail human-induced climate change and to facilitate successful adaptation to its projected impacts. Many U.S. legislators seek assurance of comparable actions by all major emitters prior to committing the United States to actions. Additional issues that may be important to Congress include the compatibility of any international agreement with U.S. domestic policies and laws; the adequacy of appropriations and fiscal incentives to achieve any commitments under the agreement; the desirable form of any agreement; and any requirements for potential ratification and implementing legislation, should a formal treaty emerge from the negotiations. Many Members of Congress are especially attentive to questions of parity of GHG actions among major trading partners, and especially to the potential for adverse competitiveness effects if some countries do not mandate GHG reductions while others move ahead. Most other major countries (including China, Brazil, and others) are taking actions, and some are measurably altering their GHG emission trajectories. The United States has taken some actions, such as establishing GHG emission limits for motor vehicles and providing fiscal incentives for energy efficiency, renewable, and other energy technologies, etc. The Environmental Protection Agency (EPA) has proposed carbon dioxide emission standards for future electric generating units as well. With existing programs and regulations, and the addition of the expected EPA regulation of GHG, the Administration believes the United States will accomplish its pledge of reducing U.S. GHG emissions to at least 17% below 2005 levels by 2020. Still, the cumulative effects of measures taken may be unlikely to achieve the deep, absolute reductions of GHG emissions considered necessary by many to stabilize atmospheric concentrations or to substantially increase rates of carbon removals from the atmosphere and sequestration (e.g., by forests and agricultural activities). Many observers have noted other risks to the U.S. economy relating to GHG abatement: some major competitors are undertaking rapid development and deployment of advanced energy technologies, justified by their domestic commitments to abating GHG emissions, enhancing energy security, reducing environmental impacts of industrial systems, and achieving additional policy objectives. Some of the countries have, correspondingly, emerged as the leading inventors and/or manufacturers of new technologies that are gaining global market shares. While fossil fuel use is unlikely to decline in the next two decades, markets for alternative technologies are expanding. Some in Congress may continue inquiries into the relationship of climate change policies to other national interests, including technological competitiveness and energy and water security.

Summary: The November 2013 negotiations in Warsaw are the most recent in a series aimed at arranging multilateral cooperation to address climate change. The United Nations launched formal international negotiations in 1990 to respond to growing scientific and public concern about human-induced emissions of greenhouse gases (GHG), principally carbon dioxide. This report chronicles the main milestones and issues in the United Nations process to address climate change. The 1992 United Nations Framework Convention on Climate Change (UNFCCC): Governments agreed in 1992 to the United Nations Framework Convention on Climate Change (UNFCCC), which continues to provide the principle—but not sole—framework for global cooperation on the issue. The treaty's objective is to stabilize GHG concentrations in the atmosphere at a level that would prevent dangerous human-induced interference with the Earth's climate system. A 2010 political statement interpreted this as a vision of GHG cuts to prevent global average temperature from increasing more than 2°C (2.6°F) above pre-industrial levels. The United States, as a Party to the UNFCCC, has qualitative obligations to report national GHG emissions; cooperate on science and technology development; enact programs to abate emissions; and provide agreed new and additional financial resources to assist low-income countries to mitigate and adapt to climate change. When the UNFCCC was drafted, the then-industrialized countries emitted two-thirds of annual GHG emissions (excluding emissions from deforestation). These Annex I countries correspondingly accepted a lead role in abating GHG emissions, though all countries agreed to "common but differentiated responsibilities." The 1997 Kyoto Protocol and its 2012 Doha Amendment: When UNFCCC entered into force in 1995, Parties agreed that enforceable obligations were necessary to prevent "dangerous climate change." The 1995 Berlin Mandate called for a new protocol by 1997 with "no new commitments for developing countries" Under the resulting 1997 Kyoto Protocol, 37 of the then-highest income countries and the European Union (EU) committed to reduce their GHG emissions on average to 5% below 1990 levels during the "first commitment period" of 2008 to 2012. The United States signed but did not become a Party to the Kyoto Protocol. The 2012 Doha Amendment to the Kyoto Protocol established a second commitment period of the Kyoto Protocol for the period 2013-2020, with GHG abatement pledges from 37 countries plus the EU. Japan, New Zealand, and the Russian Federation declined to participate in the Doha Amendment to the Kyoto Protocol. Canada withdrew from the Kyoto Protocol in 2012. The 2010 Cancun Agreement: In 2010 for the first time under the UNFCCC, a negotiated agreement contained language for GHG pledges by all major emitting Parties. Many Parties, including China, pledged quantitatively to limit their GHG emissions. However, these pledges are not considered "legally binding." Currently, the Durban Platform Negotiations: The current round of negotiations is the Durban Platform for Enhanced Action. The Durban Platform's mandate is for a new agreement "with legal force" that would be "applicable to all Parties" and begin implementation after 2020. In concept, this mandate could eliminate the bifurcation in the UNFCCC between Annex I and non-Annex I Parties, or between countries with and without binding GHG obligations. Issues for Congress: Many in Congress are concerned with the merits of a treaty, and with the goals and obligations it might embody. One concern is the compatibility of any international agreement with any U.S. domestic policies and laws, should consensus emerge on whether and how to address climate change. Additional issues include the costs and other impacts of obligations; the parity of actions among countries and effects on trade competitiveness; the adequacy of appropriations, fiscal measures, and programs to achieve any commitments under the agreement; and the desirable form of the agreement and related requirements. A new treaty would require Senate consent to ratify it as well as possible federal legislation to meet any U.S. commitments.