Editing IPCC:AR6/WGIII/Chapter-14 (section)

== 14.2 Evaluating International Cooperation ==

<div id="h1-3-siblings" class="h1-siblings"></div>

This section describes recent insights from social science theory that can shed light on the need for and ideal structure of international cooperation. This section starts by describing developments in framing the underlying problem, moves towards a body of theory describing the benefits of multilateral sub-global action, and ends with a theory-based articulation of criteria to assess the effectiveness of international cooperation.

<div id="14.2.1" class="h2-container"></div>

<span id="framing-concepts-for-assessment-of-the-paris-agreement"></span>
=== 14.2.1 Framing Concepts for Assessment of the Paris Agreement ===

<div id="h2-3-siblings" class="h2-siblings"></div>

Previous IPCC reports have framed international climate cooperation, and indeed climate mitigation more generally, primarily as addressing a global commons problem ( [[#Stavins--2014|Stavins et al. 2014]] ). In this report, by contrast, multiple framings are considered. [[IPCC:Wg3:Chapter:Chapter-1|Chapter 1]] introduces four analytic frameworks: aggregated economic approaches such as cost-benefit analysis, which maps onto the global commons framing; ethical approaches; analysis of transitions and transformations; and psychology and politics of changing course. Here, we highlight some of the findings that are of relevance to international cooperation.

When applied to the international context, the public good (or global commons) framing stresses that the incentives for mitigation at the global level are greater than they are for any single country, since the latter does not enjoy the benefits of its own mitigation efforts that accrue outside its own borders ( [[#Stavins--2014|Stavins et al. 2014]] ; [[#Patt--2017|Patt 2017]] ). This framing does not preclude countries engaging in mitigation, even ambitious mitigation, but it suggests that these countries’ level of ambition and speed of abatement would be greater if they were part of a cooperative agreement.

Theoretical economists have shown that reaching such a global agreement is difficult, due to countries’ incentives to free-ride, namely benefit from other countries’ abatement efforts while failing to abate themselves ( [[#Barrett--1994|Barrett 1994]] ; [[#Gollier--2015|Gollier and Tirole 2015]] ). Numerical models that integrate game theoretic concepts, whether based on optimal control theory or on dynamic programming, consistently confirm this insight, at least in the absence of transfers ( [[#Germain--2003|Germain et al. 2003]] ; [[#Lessmann--2015|Lessmann et al. 2015]] ; [[#Chander--2017|Chander 2017]] ). Recent contributions suggest that regional or sectoral agreements, or agreements focused on a particular subset of GHGs, can be seen as building blocks towards a global approach ( [[#Asheim--2006|Asheim et al. 2006]] ; [[#Froyn--2008|Froyn and Hovi 2008]] ; [[#Sabel--2017|Sabel and Victor 2017]] ; [[#Stewart--2017|Stewart et al. 2017]] ). In a dynamic context, this gradual approach through building blocks can alleviate the free-riding problem and ultimately lead to global cooperation ( [[#Caparrós--2017|Caparrós and Péreau 2017]] ). Much of this literature is subsumed under the concept of ‘climate clubs’ described in the next section. Other developments based on dynamic game theory suggest that the free-riding problem can be mitigated if the treaties do not prescribe countries’ levels of green investment and the duration of the agreement, as countries can credibly threaten potential free-riders with a short-term agreement where green investments will be insufficient due to the hold-up problem ( [[#Battaglini--2016|Battaglini and Harstad 2016]] ). Finally, thresholds and potential climate catastrophes have also been shown, theoretically and numerically, to reduce free-riding incentives, especially for countries that may become pivotal in failing to avoid the threshold ( [[#Barrett--2013|Barrett 2013]] ; [[#Emmerling--2020|Emmerling et al. 2020]] ).

In addition to mitigation in the form of emissions abatement, innovation in green technologies also has public good features, leading for the same reasons to less innovation than would be globally ideal ( [[#Jaffe--2005|Jaffe et al. 2005]] ). Here as well, theory suggests that there are benefits from cooperation on technology development at the regional or sectoral levels, but also that cooperation on technology, especially for breakthrough technologies, may prove to be easier than for abatement ( [[#El-Sayed--2014|El-Sayed and Rubio 2014]] ; [[#Rubio--2017|Rubio 2017]] ). In a dynamic context, the combination of infrastructure lock-in, network effects with high switching cost, and dynamic market failures suggests that deployment and adoption of clean technologies is path dependent ( [[#Acemoglu--2012|Acemoglu et al. 2012]] ; [[#Aghion--2014|Aghion et al. 2014]] ), with a multiplicity of possible equilibria. This implies that no outcome is guaranteed, although the most likely pathway will depend on economic expectations and initial conditions of the innovation process ( [[#Krugman--1991|Krugman 1991]] ). Therefore, the government has a role to play, either by shifting expectations (e.g., credibly committing to climate policy), or by changing initial conditions (e.g., investing in green infrastructure or subsidising clean energy research) ( [[#Acemoglu--2012|Acemoglu et al. 2012]] ; [[#Aghion--2014|Aghion et al. 2014]] ). This result is exacerbated by the irreversibility of energy investments and the extremely long periods of operation of the typical energy investment ( [[#Caparrós--2015|Caparrós et al. 2015]] ; [[#Baldwin--2020|Baldwin et al. 2020]] ).

While the public goods and global commons framing concentrates on free-riding incentives as the primary barrier to mitigation taking place at a pace that would be globally optimal, other factors arise across the four analytic frameworks. For example, within the political framework, [[#Beiser-McGrath--2021|Beiser-McGrath and Bernauer (2021)]] highlight that not just the incentive to free-ride, but also the knowledge that another major emitter is free-riding, could lessen a country’s political incentive to mitigate. [[#Aklin--2020|Aklin and Mildenberger (2020)]] present evidence to suggest that distributive conflict within countries, rather than free-riding across countries, is the primary barrier to ambitious national-level action. Another barrier could be a lack of understanding and experience with particular policy approaches; there is evidence that participation in cooperative agreements could facilitate information exchange across borders and lead to enhanced mitigation policy adoption ( [[#Rashidi--2018|Rashidi and Patt 2018]] ).

The analytic approach focusing on transitions and transformation focuses on path-dependent processes as an impediment to the shift to low-carbon technologies and systems. Cross-Chapter Box 12 on Transition Dynamics (Chapter 16) summarises the key points of this literature. This chapter describes how the two framings focus on different indicators of progress, and potentially different types of cooperative action within the international context. This chapter highlights in later sections conflicting views on whether the Paris Agreement is likely to prove effective ( [[#14.3.3.2|Section 14.3.3.2]] ). To some extent, the dichotomy of views aligns with the two framings: analysis implicitly aligned with the global commons framing is negative about the Paris architecture, whereas that aligned with the transitions framing is more positive ( [[#Kern--2016|Kern and Rogge 2016]] ; [[#Patt--2017|Patt 2017]] ; [[#Roberts--2018|Roberts et al. 2018]] ).

Within the global commons framing, the primary indicator of progress is the actual level of GHG emissions, and the effectiveness of policies can be measured in terms of whether such emissions rise or fall ( [[#Patt--2017|Patt 2017]] ; [[#Hanna--2021|Hanna and Victor 2021]] ). The fact that the sum of all countries’ emissions has continued to grow ( [[#IPCC--2018a|IPCC 2018a]] ), even as there has been a global recognition that they should decline, is seen as being consistent with the absence of a strong global agreement. Within this framing, there is traditionally an emphasis on treaties’ containing self-enforcing agreements ( [[#Olmstead--2012|Olmstead and Stavins 2012]] ), ideally through binding commitments, as a way of dealing with the overarching problem of free-ridership ( [[#Barrett--1994|Barrett 1994]] ; [[#Finus--2015|Finus and Caparrós 2015]] ; [[#Tulkens--2019|Tulkens 2019]] ). However, as discussed above, the emphasis has now shifted to a gradual cooperation approach, either regional or sectoral, as an alternative way of dealing with free-riding incentives ( [[#Caparrós--2017|Caparrós and Péreau 2017]] ; [[#Sabel--2017|Sabel and Victor 2017]] ; [[#Stewart--2017|Stewart et al. 2017]] ). The gradual linkage of emissions trading systems (discussed in [[#14.4.4|Section 14.4.4]] ), goes in the same direction. There is also literature suggesting that the diversity of the countries involved may in fact be an asset to reduce the free-rider incentive ( [[#Pavlova--2013|Pavlova and De Zeeuw 2013]] ; [[#Finus--2019|Finus and McGinty 2019]] ), which argues in favour of a system where all countries, irrespectively of their income levels, are fully involved in mitigation, unlike the Kyoto Protocol and in line with the Paris Agreement. Finally, recent efforts have discussed potential synergies between mitigation and adaptation efforts in a strategic context ( [[#Bayramoglu--2018|Bayramoglu et al. 2018]] ) ( [[#14.5.1.2|Section 14.5.1.2]] ) In general, current efforts go beyond considering climate policy as a mitigation-only issue, much in line with the discussion about linkages between climate change and sustainable development policies described in detail in Chapters 1 and 4 of this report.

In the transitions framing, by contrast, global emissions levels are viewed as the end (and often greatly delayed) result of a large number of transformative processes. International cooperation may be effective at stimulating such processes, even if a change in global emissions is not yet evident, implying that short-term changes in emissions levels may be a misleading indicator of progress towards long-term goals ( [[#Patt--2017|Patt 2017]] ). [[#Hanna--2021|Hanna and Victor (2021)]] suggest a particular focus on technical advances and deployment patterns in niche low-carbon technologies, such as wind and solar power, and electric vehicles. However, this is one among many suggestions: the literature does not identify a single clear indicator to use, and there are many metrics of technological progress and transformation, described in [[IPCC:Wg3:Chapter:Chapter-16#16.3.3|Section 16.3.3]] of this report. These can include national-level emissions among countries participating in particular forms of cooperation, as well as leading indicators of such emissions such as changes in low-carbon technology deployment and cost.

Just as the transition framing highlights indicators of progress other than global emissions, it de-emphasises the importance of achieving cost-effectiveness with respect to global emissions. Hence, this strand of the literature does not generally support the use of international carbon markets, suggesting that these can delay transformative processes within countries that are key drivers of technological change ( [[#Cullenward--2020|Cullenward and Victor 2020]] ). For similar reasons, achieving cross-sectoral cost-effectiveness, a goal of many carbon markets, is not seen as a high priority. Instead, within the transitions framing, the emphasis with respect to treaty design is often on providing mechanisms to support Parties’ voluntary actions, such as with financial and capacity-building support for new technologies and technology regimes ( [[#Victor--2019|Victor et al. 2019]] ). The transitions literature also highlights impediments to transformation as being sector specific, and hence the importance of international cooperation addressing sector-specific issues ( [[#Victor--2019|Victor et al. 2019]] ). While such attention often starts with promoting innovation and diffusion of low-carbon technologies that are critical to a sector’s functioning, it often ends with policies aimed at phasing out the high-carbon technologies once they are no longer needed ( [[#Markard--2018|Markard 2018]] ). In line with this, many scholars have suggested value in supply-side international agreements, aimed at phasing out the production and use of fossil fuels (Collier and Venables 2014; [[#Piggot--2018|Piggot et al. 2018]] ; [[#Asheim--2019|Asheim et al. 2019]] ; [[#Newell--2020|Newell and Simms 2020]] ).

Analytic approaches centred on equity and development figure prominently within this report, with many of the key concepts addressed in Chapter 4. Primarily the focus is on aligning climate policy at the international level with efforts to shift development pathways towards improved quality of life and greater sustainability (Cross-Chapter Box 5 in Chapter 4). There are also overlaps between the equity framework and the others. Within the global commons framing, the emphasis is on international carbon markets to reduce the costs from climate policies, and as way of generating financial flows to developing countries ( [[#Michaelowa--2019a|Michaelowa et al. 2019a]] ). The transitions framing, while focused empirically primarily on industrialised countries, nevertheless aligns with an understanding of climate mitigation taking place within a wider development agenda; in many cases it is a lack of development that creates a barrier to rapid system transformation, which international cooperation can address ( [[#Delina--2018|Delina and Sovacool 2018]] ) (Cross-Chapter Box 12 in Chapter 16).

<div id="14.2.2" class="h2-container"></div>

<span id="climate-clubs-and-building-blocks"></span>
=== 14.2.2 Climate Clubs and Building Blocks ===

<div id="h2-4-siblings" class="h2-siblings"></div>

A recent development in the literature on international climate governance has been increased attention to the potential for climate clubs ( [[#Victor--2011|Victor 2011]] ). [[#Hovi--2016|Hovi et al. (2016)]] define these as ‘any international actor group that (1) starts with fewer members than the UNFCCC has and (2) aims to cooperate on one or more climate change-related activities, notably mitigation, adaptation, climate engineering or climate compensation’. While providing public goods (such as mitigation), they also offer member-only benefits (such as preferential tariff rates) to entice membership. In practice, climate clubs are sub-global arrangements, and formal agreement by interstate treaty is not a prerequisite. Actors do not have to be states, although in the literature on climate clubs states have hitherto dominated. The literature has an essentially static dimension that focuses on the incentives for actors to join such a club, and a dynamic one which focuses on the ‘building blocks’ for global cooperative agreements.

The literature focusing on the static aspects of clubs highlight that they represent ‘coalitions of the willing’ ( [[#Falkner--2016a|Falkner 2016a]] ; [[#Gampfer--2016|Gampfer 2016]] ; [[#Falkner--2021|Falkner et al. 2021]] ), which offer a package of benefits, part of which are pure public goods (available also to non-club members), and others are club benefits that are only available to members ( [[#Hovi--2016|Hovi et al. 2016]] ). The members-only or excludable part can be a system of transfers within the club to compensate the countries with higher costs. For example, the benefit from participating in the club can be to have access to a common emissions trading system, which in general is more attractive the larger the diversity of the countries involved, although this is not a general result, as discussed in detail in [[#Doda--2017|Doda and Taschini (2017)]] . However, as costs and effort-sharing agreements are unsuccessful in a static context ( [[#Barrett--1994|Barrett 1994]] ), mainly due to free-rider incentives, several studies have proposed using tariffs on trade or other forms of sanctions to reduce incentives for free-riding ( [[#Helm--2000|Helm and Sprinz 2000]] ; [[#Eyland--2012|Eyland and Zaccour 2012]] ; [[#Anouliès--2015|Anouliès 2015]] ; [[#Nordhaus--2015|Nordhaus 2015]] ; [[#Al%20Khourdajie--2020|Al Khourdajie and Finus 2020]] ). For example, [[#Nordhaus--2015|Nordhaus (2015)]] uses a coalition formation game model to show that a uniform percentage tariff on the imports from nonparticipants into the club region (at a relatively low tariff rate of about 2%) can induce high participation within a range of carbon price values. More recently, [[#Al%20Khourdajie--2020|Al Khourdajie and Finus (2020)]] show that border carbon adjustments and an open membership policy can lead to a large stable climate agreement, including full participation. Table 14.1 presents a number of key results related to climate clubs from a static context.

'''Table 14.1 | Key climate club static modelling results.'''

{| class="wikitable"
|-
!
! Aakre et al. (2018)

! [[#Nordhaus--2015|Nordhaus (2015)]]

! [[#Hovi--2017|Hovi et al. (2017)]] ; [[#Sprinz--2018|Sprinz et al. (2018)]]

! [[#Sælen--2020|Sælen (2020)]] ; [[#Sælen--2020|Sælen et al. (2020)]]

|-
| Scope

| Transboundary black carbon and methane in the Arctic

| Global emissions

| Global emissions

| Global emissions

|-
| Modelling method

| TM5-FASST model (‘reduced-form air quality and impact evaluation tool’)

| C-DICE (coalition formation game based on a static version of the multiregional DICE-RICE optimisation model)

| Agent-based model

| Agent-based model

|-
| Border tax adjustment

| No

| Yes

| No

| No

|-
| Key results

| Black carbon can be more easily controlled than methane, based on self-interest; inclusion of non-Arctic Council major polluters desirable to control pollutants

| For non-participants in mitigation efforts, modest tariffs on trade are advised to stabilise coalition formation for emissions reductions

| Climate clubs can substantially reduce GHG emissions, provided club goods are present. The (potential) departure of a single major actor (e.g., USA) reduces emissions coverage, yet is rarely fatal to the existence of the club

| The architecture of the Paris Agreement will achieve the 2°C goal only under a very fortunate constellation of parameters. Potential withdrawal (e.g., USA) further reduces these chances considerably

|}

In a dynamic context, the literature on climate clubs highlights the co-called ‘building blocks’ approach ( [[#Stewart--2013a|Stewart et al. 2013a]] ,b, 2017). This is a bottom-up strategy designed to create an array of smaller-scale, specialised initiatives for transnational cooperation in particular sectors and/or geographic areas with a wide range of participants. As part of this literature, [[#Potoski--2013|Potoski and Prakash (2013)]] provide a conceptual overview of voluntary environmental clubs, showing that many climate clubs do not require demanding obligations for membership and that a substantial segment thereof are mostly informational ( [[#Weischer--2012|Weischer et al. 2012]] ; [[#Andresen--2014|Andresen 2014]] ). Also crafted onto the building blocks approach, [[#Potoski--2017|Potoski (2017)]] demonstrates the theoretical potential for green certification and green technology clubs. [[#Green--2017|Green (2017)]] further highlights the potential of ‘pseudo-clubs’ with fluid membership and limited member benefits to promote the diffusion and uptake of mitigation standards. [[#Falkner--2021|Falkner et al. (2021)]] suggest a typology of normative, bargaining, and transformational clubs. Before the adoption of the Paris Agreement, some literature suggested that the emergence of climate clubs in parallel to the multilateral climate regime would lead to ‘forum shopping’, with states choosing the governance arrangement that best suits their interests ( [[#McGee--2006|McGee and Taplin 2006]] ; [[#van%20Asselt--2007|van Asselt 2007]] ; [[#Biermann--2009|Biermann et al. 2009]] ; [[#Oh--2017|Oh and Matsuoka 2017]] ). However, more recent literature suggests that climate clubs complement rather than challenge the international regime established by the UNFCCC ( [[#van%20Asselt--2014|van Asselt and Zelli 2014]] ; [[#Falkner--2016a|Falkner 2016a]] ; [[#Draguljić--2019|Draguljić 2019]] ).

In this dynamic context, one question is whether to negotiate a single global agreement or to start with smaller agreements in the hope that they will eventually evolve into a larger agreement. It has been debated extensively in the context of free trade whether a multilateral (global) negotiating approach is preferable to a regional approach, seen as a building block towards global free trade. [[#Aghion--2007|Aghion et al. (2007)]] analysed this issue formally for trade, showing that a leader would always choose to move directly to a global agreement. In the case of climate change, it appears that even the mildest form of club discussed above (an efforts and costs sharing agreement, as in the case of the linkage of emissions trading systems) can yield global cooperation following a building blocks approach, and that the sequential path relying on building blocks may be the only way to reach global cooperation over time ( [[#Caparrós--2017|Caparrós and Péreau 2017]] ). While the existence of a nearly universal agreement such as the Paris Agreement may arguably have rendered this discussion less relevant, the Paris Agreement co-exists, and will likely continue to do so, with a multitude of sectoral and regional agreements, meaning that this discussion is still relevant for the evolution of these complementary regimes.

Results based on an agent-based model suggest that climate clubs result in major emissions reductions if there is a sufficiently high provision of the club good and if initial membership by several states with sufficient emissions weight materialises. Such configurations allow the club to grow over time to enable effective global action ( [[#Hovi--2017|Hovi et al. 2017]] ). The departure of a major emitter (specifically the United States) triggered a scientific discussion on the stability of the Paris Agreement. [[#Sprinz--2018|Sprinz et al. (2018)]] explore whether climate clubs are stable against a leader willing to change its status, for example, from leader to follower, or even completely leaving the climate club, finding in most cases such stability to exist. Related studies on the macroeconomic incentives for climate clubs by [[#Paroussos--2019|Paroussos et al. (2019)]] show that climate clubs are reasonably stable, both internally and externally (i.e., no member willing to leave and no new member willing to join), and climate clubs that include obligations in line with the 2°C goal combined with financial incentives can facilitate technology diffusion. The authors also show that preferential trade arrangements for low-carbon goods can reduce the macroeconomic effects of mitigation policies. [[#Aakre--2018|Aakre et al. (2018)]] show numerically that small groups of countries can limit black carbon in the Arctic, driven mainly for reasons of self-interest, yet reducing methane requires larger coalitions due to its larger geographical dispersal and requires stronger cooperation.

<div id="14.2.3" class="h2-container"></div>

<span id="assessment-criteria"></span>
=== 14.2.3 Assessment Criteria ===

<div id="h2-5-siblings" class="h2-siblings"></div>

This section identifies a set of criteria for assessing the effectiveness of international cooperation, which is applied later in the chapter. Lessons from the implementation of other multilateral environmental agreements (MEAs) can provide some guidance. There is considerable literature on this topic, most of which predates AR5, and which will therefore not be covered in detail. Issues include ways to enhance compliance, and the fact that a low level of compliance with an MEA does not necessarily mean that the MEA has no effect ( [[#Downs--1996|Downs et al. 1996]] ; [[#Victor--1998|Victor et al. 1998]] ; Weiss and Jacobson 1998). Recent research examines effectiveness from the viewpoint of the extent to which an MEA influences domestic action, including the adoption of implementing legislation and policies ( [[#Brandi--2019|Brandi et al. 2019]] ).

Many have pointed to the Montreal Protocol, addressing stratospheric ozone loss, as an example of a successful treaty because of its ultimate environmental effectiveness, and relevance for solving climate change. Scholarship emerging since AR5 emphasises that the Paris Agreement has a greater ‘bottom-up’ character than many other MEAs, including the Montreal or Kyoto Protocols, allowing for more decentralised ‘polycentric’ forms of governance that engage diverse actors at the regional, national and sub-national levels ( [[#Ostrom--2010|Ostrom 2010]] ; [[#Jordan--2015|Jordan et al. 2015]] ; [[#Falkner--2016b|Falkner 2016b]] ; [[#Victor--2016|Victor 2016]] ). Given the differences in architecture, lessons drawn from studies of MEA regimes need to be supplemented with assessments of the effectiveness of cooperative efforts at other governance levels and in other forums. Emerging research in this area proposes methodologies for this task ( [[#Hsu--2019a|Hsu et al. 2019a]] ). Findings highlight the persistence of similar imbalances between developed and developing countries as at the global level, as well as the need for more effective ways to incentivise private sector engagement in transnational climate governance ( [[#Chan--2018|Chan et al. 2018]] ).

While environmental outcomes and economic performance have been long-standing criteria for assessment of effectiveness, the other elements deserve some note. It is the case that the achievement of climate objectives, such as limiting global average warming to 1.5°C–2°C, will require the transition from high- to low-carbon technologies and the transformation of the sectors and social environments within which those technologies operate. Such transformations are not linear processes, and hence many of the early steps taken – such as supporting early diffusion of new renewable energy technologies – will have little immediate effect on GHG emissions ( [[#Patt--2015|Patt 2015]] ; [[#Geels--2017|Geels et al. 2017]] ). Hence, activities that contribute to transformative potential include technology transfer and financial support for low-carbon infrastructure, especially where the latter is not tied to immediate emissions reductions. Assessing the transformative potential of international cooperation takes these factors into account. Equity and distributive outcomes are of central importance to the climate change debate, and hence for evaluating the effects of policies. Equity encompasses the notion of distributive justice which refers to the distribution of goods, burdens, costs and benefits, as well as procedural-related issues ( [[#Kverndokk--2018|Kverndokk 2018]] ).

Finally, the literature on the performance of other MEAs highlights the importance of institutional strength, which can include regulative quality, mechanisms to enhance transparency and accountability, and administrative capacity. Regulative quality includes guidance and signalling ( [[#Oberthür--2017|Oberthür et al. 2017]] ), as well as clear rules and standards to facilitate collective action ( [[#Oberthür--2016|Oberthür and Bodle 2016]] ). The literature is clear that legally-binding obligations (which require the formal expression of state consent) and non-binding recommendations can each be appropriate, depending on the particular circumstances ( [[#Skjærseth--2006|Skjærseth et al. 2006]] ), and indeed it has been argued that for climate change non-binding recommendations may better fit the capacity of global governance organisations ( [[#Victor--2011|Victor 2011]] ). Mechanisms to enhance transparency and accountability are essential to collect, protect, and analyse relevant data about Parties’ implementation of their obligations, and to identify and address challenges in implementation ( [[#Kramarz--2016|Kramarz and Park 2016]] ; [[#Kinley--2020|Kinley et al. 2020]] ). Administrative capacity refers to the strength of the formal bodies established to serve the Parties to the regime and help ensure compliance and goal attainment ( [[#Andler--2009|Andler and Behrle 2009]] ; [[#Bauer--2017|Bauer et al. 2017]] ).

In addition to building on the social science theory just described, we recognise that it is also important to strike a balance between applying the same standards developed and applied to international cooperation in AR5 and maintaining consistency with other chapters of this report (primarily Chapters 1, 4, 13 and 15). Table 14.2 presents a set of criteria that do this, and which are then applied later in the chapter.

'''Table 14.2 | Criteria for assessing effectiveness of international cooperation.'''

{| class="wikitable"
|-
! '''Criterion'''

! '''Description'''

|-
| Environmental outcomes

| To what extent does international cooperation lead to identifiable environmental benefits, namely the reduction of economy-wide and sectoral emissions of greenhouse gases from pre-existing levels or ‘business as usual’ scenarios?

|-
| Transformative potential

| To what extent does international cooperation contribute to the enabling conditions for transitioning to a zero-carbon economy and sustainable development pathways at the global, national, or sectoral levels?

|-
| Distributive outcomes

| To what extent does international cooperation lead to greater equity with respect to the costs, benefits, and burdens of mitigation actions, taking into account current and historical contributions and circumstances?

|-
| Economic performance

| To what extent does international cooperation promote the achievement of economically efficient and cost-effective mitigation activities?

|-
| Institutional strength

| To what extent does international cooperation create the institutional framework needed for the achievement of internationally agreed-upon goals, and contribute to national, sub-national, and sectoral institutions needed for decentralised and bottom-up mitigation governance?

|}

<div id="14.3" class="h1-container"></div>

<span id="the-unfccc-and-the-paris-agreement"></span>