Public International Law/Climate Change Law





Author: Required knowledge: International Environmental Law

Learning objectives:


 * 1) Discern the multifaceted implications of climate change from various lenses including biophysical, socioeconomic, and political perspectives, to appreciate the complexities involved in formulating international legal responses.
 * 2) Identify the core principles of international climate change law, the major stakeholders, their interests, and the inherent political challenges, utilizing the terminology specific to the UNFCCC.
 * 3) Understand the development, functionality, and criticisms of the main mechanisms in the international climate change treaty regime, incorporating historical context and current scholarship in the field.
 * 4) Understand how climate change law interacts with other areas of international law, with a particular focus on multilateral environmental agreements and human rights law, and how these intersections can enhance climate change mitigation and adaptation strategies.
 * 5) Critically examine the potential opportunities, challenges, and the role of international climate change law in achieving climate justice, integrating contemporary literature and ongoing debates in the field. This is where the text begins. This template follows our style guide. Please take into account our guidelines for didactics. If you're wondering how to create text in Wikibooks, feel free to check out our  guide on how to write in Wikibooks.

A. Introduction
[T]he climate crisis is so violent and has exacerbated so much injustice […] It is not only the biggest challenge humanity has ever faced but also the biggest opportunity we have to change the world.

– Xiye Bastida, Climate Justice Activist. Today, we know with high certainty that the emission of greenhouse gases (GHG) into the atmosphere, a consequence of human activities, has warmed the climate at an unprecedented rate. By altering the composition of the global atmosphere, such anthropogenic release of gases has induced a change in the state of the climate over extended periods, a phenomenon known as "climate change." In its most recent Sixth Assessment Report (AR6), the Intergovernmental Panel on Climate Change (IPCC)—the lead scientific body on climate change—attests that climate change is already affecting every region across the globe by altering the frequency and intensity of heatwaves, heavy precipitations, droughts, and tropical cyclones. Concerningly, the report's projection about a continuous increase in the global surface temperature until mid-century has become increasingly evident. This claim has been further corroborated by a recent update from the World Meteorological Organization (WMO) issued in May 2023. The WMO states that there is a 66% likelihood that the annual average global temperature, measured near the Earth's surface, will exceed 1.5°C above pre-industrial levels for at least one year between 2023 and 2027. Additionally, it indicates a 98% likelihood that at least one of the next five years—and the overall five-year period—will be the warmest on record. In the face of such compelling evidence, it becomes crucial to drastically reduce GHG emissions in the forthcoming decades. Otherwise, the global warming threshold of 1.5°C and 2°C could be exceeded within the 21st century, ushering in a host of serious risks to both ecosystems and human societies.

Climate change's complexities extend beyond the simple correlation between human-induced emissions and an amplified greenhouse effect—on which the IPCC concentrated in its earliest reports. This issue is intertwined with how current socioeconomic and political systems function and distribute resources. For instance, while the top 10% of the global population is responsible for half of all CO2 emissions, the bottom 57%—those living below the World Bank poverty line—generated only 16%. These vulnerable groups, often marginalized due to gender, race, or ethnicity, are disproportionately impacted by climate change due to limited coping mechanisms and resources. Indeed, between 2010 and 2020, such populations suffered 15 times higher mortality from climate-induced disasters than those in less vulnerable regions. Consequently, climate change—a 'wicked problem,' as some have famously labeled it —demands deep and fast transformations not only in the environmental sphere but also in how the current social, economic, and even political systems work.

To confront this global problem, the international community responded by establishing a multilateral climate change regime to mitigate and adapt to climatic changes. Initiated by the 1990 United Nations General Assembly (UNGA) Resolution 45/212, the United Nations Framework Convention on Climate Change (UNFCCC) became the bedrock for contemporary international climate change law. This Convention serves as the foundational framework through which climate change has been comprehended and incorporated into the legal arena. It articulates the core concepts and principles related to climate change and provides a platform for other legislative instruments that contribute to the evolving international climate change regime. Over time, this regime has experienced transformations in its legal form, character, and architecture. It has walked away from its original niche in environmental law to, for some commentators, even forge its own identity and interconnect with other fields of law, such as human rights and financial law. However, with the global temperature trajectory surpassing 2°C, the efficacy of such laws is under scrutiny. Meanwhile, young activists —including Xiye Bastida, a climate justice activist from Mexico, and Greta Thunberg, the young founder of #FridaysForFuture —are advocating for a carbon-free world. Hence, the study of international climate change law should critically assess its potential and constraints in tackling climate change. This chapter aims to provide an overview of the UNFCCC, the Kyoto Protocol, and the Paris Agreement, while emphasizing the deeply rooted socioeconomic and political systems that contribute to climate change. It seeks to foster critical thinking in overcoming the limits of international climate change law and realizing the change young activists envision.

1. Concepts
The core objective of international climate change law, as established by Article 2 of the UNFCCC, is ‘to achieve […] stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system.’ To accomplish this, much of international climate change law spans two different sets of actions: mitigation and adaptation. On the one hand, human interventions aimed at mitigating climate change seek to reduce GHG emissions, including preserving carbon sinks such as wetlands and forests. And on the other, adaptation involves actions geared at adjusting to the actual or expected climate and its effects.

Commitments under the UNFCCC concern both mitigation and adaptation. They span the development of programs, international cooperation, education, and public awareness. For example, Article 4 of the Convention sets out that all parties shall "‘[f]ormulate, implement, publish and regularly update national and, where appropriate, regional programmes containing measures to mitigate climate change by addressing anthropogenic emissions by sources and removals by sinks of all greenhouse gases […] and measures to facilitate adequate adaptation to climate change.’"However, despite the dual emphasis of the Convention, during the first decade of the UN climate regime, efforts concentrated mainly on mitigation. This is reflected in the fact that the first legally binding instrument that arose from the Convention, the 1997 Kyoto Protocol, prescribed specific GHG mitigation targets and timetables while not laying the same focus on climate adaptation. It was not until the Convention’s second legally binding instrument, the 2015 Paris Agreement, that the UNFCCC climate regime strengthened the importance of climate adaptation by agreeing to define a global goal on adaptation.

2. Implementation and Oversight Mechanisms
The UNFCCC established a Conference of the Parties (COP) and a permanent secretariat which facilitate negotiations. Article 7 of the UNFCCC confers on the COP the status of the supreme body of the Convention and the duty to keep its implementation under regular review. The COP meets every year. The first COP meeting (COP1) was held in Berlin, Germany in March, 1995. The latest meeting (COP27) took place in Sharm el-Sheikh, Egypt in November 2022. Further, Article 8 of the Convention set a secretariat to make arrangements for the COP meetings, facilitate assistance to the parties, and ensure coordination with the secretariats of other relevant international bodies, among other functions. The secretariat is located in Bonn, Germany and employs around 450 staff from over 100 countries.

Besides these institutions, other issues structural to the international climate change regime are its means of implementation, namely its financial and oversight mechanisms. The UNFCCC climate regime sets the commitment for developed countries to provide financial resources to developing countries as an instrumental measure to advance climate action. Because meeting the costs of mitigation and adaptation is instrumental for accomplishing the regime’s objectives, the parties to the Convention have agreed on establishing a financial mechanism and special funds to facilitate the flow of resources. The operating entities of the financial mechanism set by the UNFCCC are the Global Environmental Facility (GEF) and the Green Climate Fund (GCF). Special funds complement the primary mechanism and support specific countries and projects through the Special Climate Change Fund, the Least Developed Countries Fund, and the Adaptation Fund.

The UNFCCC climate regime has also created oversight mechanisms to ensure implementation and compliance. The Convention requires states to periodically communicate their mitigation and adaptation measures' progress as a general means for promoting accountability. The Kyoto Protocol and the Paris Agreement set their implementation frameworks, as the following sub-sections of this chapter will elaborate.

3. Principles
Principles form the bedrock of international climate change law, with roots in general and international environmental law.These principles encompass the no-harm rule, its complementary obligation of due diligence, and the principle of common but differentiated responsibility (CBDR).

The no-harm rule, a cornerstone of international environmental law, obliges states to ensure activities within their jurisdiction don't harm the environment of other states or areas beyond national jurisdiction. The 1972 Stockholm Declaration of the UN Conference on the Human Environment and the 1992 Rio Declaration on Environment and Development set the responsibility of states to ensure that activities within their jurisdiction do not cause damage to the environment of other states or areas beyond the limits of national jurisdictions. The International Court of Justice (ICJ) emphasizes this obligation as requiring states to take appropriate measures to prevent harm to other states' environment or the global commons, linking it with the due diligence principle. The latter demands that states enforce preventive measures with a certain level of vigilance over both public and private operators. The UNFCCC broadens the scope of the no-harm rule, incorporating potential harms lacking full scientific certainty—embracing the precautionary principle outlined in Principle 15 of the Rio Declaration.

The CBDR principle, initially codified in the Rio Declaration and subsequently adopted by the UNFCCC, acknowledges shared yet differing responsibilities among states for preventing harmful interference with the climate system. This principle takes into account historical contributions to the problem and current capacities to respond, thus accounting for national and regional development priorities, objectives, and circumstances.

II. Stakeholders and Politics
While states have traditionally led international climate change law development, both intergovernmental organizations and non-state actors have gained influence within the UNFCCC, participating actively in Conferences of Parties (COPs). Their rise in prominence has, directly or indirectly, impacted the trajectory of international climate change law. These non-state actors or NGOs, including nonprofit organizations, private corporations, trade unions, and academic institutions, have seen their participation within the UNFCCC process increase. Currently, they are grouped into nine constituencies: Business and industry NGOs (BINGO), Environmental NGOs (ENGO), Farmers, Indigenous peoples organizations (IPO), Local government and municipal authorities (LGMA), Research and independent NGOs (RINGO), Trade union NGOs (TUNGO), Women and Gender (WGC), and Youth NGOs (YOUNGO). The IPCC, established in 1988, is another key player. This body of 195 governments provides scientific data on climate change, informing international climate negotiations. To date, six assessment reports (AR) highlighting critical areas for climate action have been issued. AR1 was issued in 1990, and the most recent AR6 was in 2022. The work of the IPCC thereby constitutes an essential input for international climate change negotiations.

The varying interests and concerns colliding in the UNFCCC process, due to the diverse participants, expose the political complexities challenging international climate change law. Three distinct perspectives on climate change have emerged amongst these actors. Some, mainly European states and organizations, regard climate change primarily as an environmental issue, advocating for a reduction in greenhouse gas emissions. Conversely, other entities, including non-European high-income countries like the US, approach climate change as an economic issue. They support emissions reduction only when benefits exceed costs, prioritizing economic growth and job creation. Global South countries and organizations, however, frame climate change as a matter of 'climate justice'. Despite contributing minimally to the problem, these nations bear the brunt of its effects. Therefore, they call for high-income countries to acknowledge and assume their responsibilities, including reparations for damage caused by climate change.

These differing viewpoints have shaped the evolution of the international climate change regime, creating opportunities and obstacles in reaching global agreements. As a result, international climate change law has adapted its form and structure to navigate these complex political tensions. The subsequent section examines the UNFCCC regime's three core agreements and their responses to these contextual political challenges.

I. Emergence of the UNFCCC
Early scientific research into climate change revealed rising atmospheric CO2 levels during the 1960s. Enhanced computing power in the subsequent decades deepened our understanding of the issue, leading the 1979 US National Academy of Sciences report to state that unabated increases in CO2 would result in significant climate change. The First World Climate Conference convened in Geneva that year under the WMO, resulting in an urgent appeal for nations to anticipate and mitigate potential climate changes harmful to humanity. The conference laid the foundation for the World Climate Program and future climate-focused assemblies, such as the 1985 Villach Conference and the 1988 Toronto Conference.

During the 1980s and 1990s, escalating environmental activism and political developments like the adoption of the 1987 Montreal Protocol and the 1992 Rio Conference helped raise public awareness on climate issues. This, in turn, pressed policymakers to prioritize environmental protection, including atmospheric preservation. The amalgamation of scientific advancement and growing social and political awareness facilitated the global recognition of climate change, cementing it as an international law concern. In 1988, the WMO and UNEP founded the IPCC and the United Nations General Assembly recognized climate change as a 'common concern of mankind.'

In 1989, the Netherlands hosted the Hague Summit and the Noordwijk meeting, the first high-level intergovernmental forum devoted exclusively to climate change. That same year, the climate issue was on the agenda of various international summits, including the Small Island States meeting, the Francophone Summit in Dakar, the G7 Meeting, the Non-Aligned meeting, and the Commonwealth Summit. The Second World Climate Conference in 1990 issued a widely endorsed call for global action on climate change, setting the stage for the negotiation of the UNFCCC. The IPCC also published its inaugural report on climate change's scientific, environmental, and policy implications.

II. Evolution of the UNFCCC
In 1990, the UNGA adopted Resolution 45/212, setting in motion the creation of the UNFCCC. Entrusted by the General Assembly, the Intergovernmental Negotiating Committee (INC) finalized the Convention in 1992, and it came into effect two years later when it achieved ratification by fifty countries. The Convention aims to stabilize greenhouse gas concentrations to prevent dangerous interference with the climate system. It sets out five guiding principles: (1) the CBDR principle, urging developed nations to lead in climate change mitigation, (2) special attention to the needs of developing countries, (3) the precautionary principle, (4) the right to sustainable development, and (5) the importance of cooperation in an open international economic system.

These principles reflect the tensions between developed and developing countries concerning equity, which influenced the Convention's commitments. The CBDR principle, in particular, underscores the Convention's distinction between 'Annex I' (developed) and 'non-Annex I' (developing) countries. Annex I countries, including members of the Organization for Economic Cooperation and Development (OECD) and nations with economies in transition, are encouraged to limit greenhouse gas emissions to 1990 levels by 2000. Annex II, a subgroup of Annex I, are expected to provide financial resources to assist developing countries in adapting to climate change. Non-Annex I parties, mostly developing nations, include the United Nations' 49 classified Least Developed Countries (LDCs) which receive special consideration due to their limited capacity to adapt to climate change.

Moreover, the Convention recognizes the importance of economic development and promotes an open international economic system. While it does not set specific emission targets, the UNFCCC establishes general obligations and provides a base for international climate change regulation. Its importance extends beyond previous conventions by setting up a financial mechanism (Article 11), requiring detailed reporting (Article 12) and international review (Article 7.2(e)).

III. The Kyoto Protocol
The Kyoto Protocol, adopted in 1997, emerged due to the UNFCCC's lack of specific emission reduction targets. This development started with the 1995 Berlin Mandate at the first Conference of the Parties (COP), which established the Ad Hoc Group (AGBM) to craft a robust legal instrument to fortify the UNFCCC. The AGBM's work culminated in the Kyoto Protocol's adoption in 1997 during COP3. However, its strict provisions led to challenges in securing participation, only entering into force in 2005 when ‘enough’ Annex I parties (accounting for at least 55% of the total CO2 emissions for 1990) deposited their instruments of ratification, acceptance, approval or accession.

The Kyoto Protocol's goal was to enforce emission reduction targets for Annex I countries, introducing a commitment period (2008-2012) during which parties aimed to reduce their GHG emissions by 5% below 1990 levels. The protocol also mandated national systems for estimating GHG emissions by 2007 and periodic reporting on progress. Perhaps among the most salient features of the Kyoto Protocol are the implementation mechanisms it established. They are three: the Clean Development Mechanism (CDM) set up under Article 12, the Joint Implementation (JI) defined by Article 6, and the Emissions Trading (ET) set out in Article 16bis. The CDM allows countries with emission reduction commitments (Annex I parties) to undertake emission reduction projects in non-Annex I countries. In so doing, the former countries earn saleable certified emission reduction (CER) credits (each equivalent to one tonne of CO2) that count towards their Kyoto targets. Similarly, the JI provided the opportunity for Annex I countries to transfer to, or acquire from, any other such Party emission reduction Units (ERUs) resulting from emission reduction projects implemented in another Annex I country. Each ERU is equivalent to one tonne of CO2, which counts toward meeting these countries’ Kyoto targets.

The ET scheme allowed countries whose actual emissions did not surpass their emission reduction commitments—and thus had emission units to spare—to sell this excess capacity to countries that were over their targets. In this way, a new commodity was created through emission reductions or removals, whereby carbon is tracked and traded like any other commodity. Since CO2 is the main GHG, emissions trading is often known as the ‘carbon market.’ CER and ERU units from the CDM and JI, respectively, can also be transferred under this market.

However, the Kyoto Protocol's architecture, a top-down approach with clear delineations between developed and developing countries, posed some significant challenges. Its prescriptive nature and favor towards developing countries led to the withdrawal of the United States in 2001, one of the largest GHG emitters. Given such a significant withdrawal and the fact that China (a non-Annex I country yet also a major GHG emitter) was not given emission reduction commitments under the Protocol, this treaty’s emissions targets encompassed less than 24% of global GHG emissions.

In 2012, the 'Doha Amendment' extended the Kyoto Protocol's first commitment period (2008-2012) to a second period from 2013 to 2020. Nonetheless, due to the same structural issues as the original Kyoto Protocol, several developed country parties opted out from the second commitment period, including Canada, Japan, and Russia, further limiting the Protocol's scope.

IV. The Paris Agreement
Replacing the Kyoto Protocol, the Paris Agreement acts as the foundation for specific climate commitments, adopted by the COP during its 21st session in 2015. It marks the first time human rights have been explicitly mentioned in a climate treaty—yet only in its preamble. The development of the Paris Agreement was a politically fraught process starting with the adoption of the 'Bali Action Plan' in 2007. This plan instigated a process that aimed to implement a full, effective, and long-term cooperative action plan under the Convention, originally intended for completion by 2009. The core contention throughout this process was the differentiation of emission reduction commitments between developed and developing countries. The failure to agree on this differentiation led to the inconclusive COP15 in Copenhagen in 2009. The resulting Copenhagen Accords reemphasized the Plan’s invitation to developed countries to submit emission reduction targets for 2020 and to developing countries to submit nationally appropriate mitigation actions.

A new attempt to develop a legal instrument under the Convention was formalized in 2011 at the 17th session of the COP in Durban, South Africa. COP17 established the Ad Hoc Working Group on the Durban Platform for Enhanced Action (AWG-DP), a process that would lead to an agreed outcome with legal force to be implemented from 2020. That outcome was the Paris Agreement, whose architecture, influenced by the route the preceding negotiations took, contrasts with the Kyoto Protocol, particularly in how it treats the distribution of countries’ emission reduction commitments.

The Paris Agreement's Article 2 outlines two central goals: mitigation and adaptation to climate change. The mitigation aim strives to limit the global temperature increase to well below 2°C and urges efforts to restrict the rise to 1.5°C above pre-industrial levels. It also advocates for adaptation to the adverse impacts of climate change and fostering climate resilience. Furthermore, unlike the Kyoto Protocol, the Paris Agreement refrains from mandating differentiated emission reduction targets based on the countries' development trajectories. Instead, it calls for mitigation actions from all parties while recognizing the principle of CBDR. The Agreement's implementation thus entails certain differentiation between developed and developing countries. For example, it expresses the ‘aim’ of Parties to ‘reach global peaking of greenhouse gas emissions as soon as possible, recognizing that peaking will take longer for developing country Parties, and to undertake rapid reductions thereafter […]’ It also mandates developed parties to continue 'taking the lead' in emission reduction targets and support developing countries in implementing the Agreement.

New principles introduced in the Paris Agreement include the maximum ambition and progression principles. These principles establish a foundation for increasing ambition, requiring each party to periodically enhance its level of commitment over the 5-year cycle. The Agreement employs tools like nationally determined contributions (NDCs), long-term strategies (LT-LEDS), adaptation plans, and the global stocktake for achieving its objectives. NDCs are action plans that both developed and developing countries must communicate every five years, showing a progressive increase in ambition. The NDC cycle began in 2020 when all parties were welcome to submit their initial updated communications.

Furthermore, the Paris Agreement invites countries to ‘formulate and communicate long-term low greenhouse gas emission development strategies’ (LT-LEDS). These strategies define the long-term horizon to the NDCs. However, unlike NDCs, LT-LEDS are not mandatory. The Paris COP15 invited state parties to communicate their LT-LEDS by 2020. As of August 2022, 51 countries had submitted their strategies, including the European Union, United States, and China, the world’s top GHG emitters.

Unlike the Kyoto Protocol, the Paris Agreement employs a hybrid architecture that blends top-down and bottom-up approaches. The Agreement's objectives and principles, established by multilateral negotiations, reflect a top-down approach, while the NDCs and adaptation arrangements follow a bottom-up template. This structure grants each state the flexibility to set its mitigation ambition level and incorporates these commitments into an international climate accountability system through a global stocktake, which assesses collective progress and informs the determination of subsequent NDCs and communications. The hybrid architecture of the Paris Agreement has enhanced participation levels compared to its predecessor: a record 175 parties signed the Agreement on its opening day, April 22, 2016, and it came into force less than a year after its adoption.

However, there are concerns about the Agreement's potential to meet the urgent need for global decarbonization, considering that countries' GHG reduction commitments' levels of ambition are left to the states themselves. Despite the Paris Agreement's maximum ambition principle, these concerns are not unfounded, given that governments often express high aspirations but shy away from difficult decisions. As indicated in the advanced box above, the current ambition levels of submitted NDCs are insufficient to prevent global warming beyond 1.5°C.

D. International Climate Change Law beyond the UNFCCC
The UNFCCC treaty regime is a focal point in international climate change law. Nonetheless, the scope extends beyond this treaty. The relevance and substance of international climate change law have expanded considerably, reaching out of its initial confines in environmental law. Some observers even propose that it has developed its own distinct identity, intersecting with various legal domains. As climate change permeates almost all facets of human life, norms in other international law areas regulating such facets also intertwine with global warming concerns. These domains include international environmental law, human rights law, trade and investment law, refugee and migration law, and the law of the sea.

This segment focuses on how international environmental law and human rights law address climate change, thereby enriching international climate change law. While legal perspectives from other areas are crucial, numerous multilateral environmental agreements (MEAs) share a particularly close relationship with climate change, as their principles have significantly influenced the UNFCCC. Concurrently, the convergence of climate change and human rights law has forged new avenues, seemingly amplifying the influence of international climate change law, evidenced by the recent surge in rights-based climate litigation.

The Ramsar Convention
Adopted in the city of Ramsar, Iran and in force since 1975, the Ramsar Convention promotes the conservation of wetlands (areas of marsh, fen, peatland, or water with water that is static or flowing, fresh, brackish, or salt) that hold international significance in terms of their environmental characteristics. Despite not directly addressing climate change, it identifies the threats global warming imposes on the ecosystems under its protection. For example, peatlands and mangroves, key components of wetlands, play significant roles in carbon storage and disaster risk reduction. Recognizing the climate mitigation and adaptation capabilities of wetlands, the Conference of the Parties to the Ramsar Convention (COP-Ramsar) has incorporated climate change considerations into the management and protection of these vital ecosystems. Particularly, in 2002, it adopted Resolution VIII.3 on 'Climate change and wetlands; impacts, adaptation and mitigation,' which the Conference subsequently updated through Resolution X.24 during its 10th Meeting in 2008. This superseding resolution entitled 'Climate change and wetlands' mandated contracting countries, among other measures, to ‘include in national climate change strategies the protection of wetlands’ and to ‘improve management practices of peatlands and other wetland types that are significant GHG sinks.’

The Convention on Biological Diversity
Effective since 1993, the CBD has three primary objectives: the conservation of biological diversity, sustainable use of ecosystem components, and equitable sharing of benefits arising from their genetic resources. Recognizing the inseparable connection between biodiversity conservation and climate change, the CBD integrates climate change concerns into its core operations[9]. Notably, the findings of the 3rd Global Biodiversity Outlook (GBO), published in 2010, led the Conference of the Parties to the CBD (COP-CBD) to adopt the Strategic Plan 2011-2020 and the Aichi Biodiversity Targets, which include climate-related measures in two strategic goals.

The post-2020 Kunming-Montreal Global Biodiversity Framework has continued this trend by including targets designed to directly respond to the impacts of climate change. This framework has 23 action-oriented global targets, of which three seek to respond directly to the impacts of climate change. First, target 8 calls for minimizing the effects of climate change and ocean acidification on biodiversity and increasing its resilience through mitigation, adaptation, and disaster risk reduction actions. Second, the framework's target 11 pursues the restoration, maintenance, and enhancement of nature's contributions to people, including the climate. And third, target 19 commends the increase of financial resources by optimizing co-benefits and synergies targeting the biodiversity and climate crises.

Environmental Governance Agreements
The Espoo Convention, a European MEA adopted in 1991, guides countries to implement national environmental impact assessment (EIA) procedures to manage adverse transboundary environmental impacts. While not fully encompassing climate change in its provisions, its Kyiv Protocol, in force since 2010, requires a strategic EIA irrespective of the transboundary context, thereby considering effects on the global environment. Further, the EU Commission has called for the mainstreaming of climate mitigation measures into member states’ legislation on EIA and therefore issued guidance documents in 2013 and a directive in 2014 on the matter, which ultimately reverberates on the implementation of the Espoo Convention and its Protocol.

The Escazú Agreement, focusing on Latin America and the Caribbean, assures access to environmental information, public participation, and justice in environmental matters. Adopted in 2018, it commands countries to reveal updated information on climate change sources and encourages public involvement, including in their National Determined Contributions (NDCs). Through these directives, the agreement emphasizes a more inclusive and transparent approach to climate change mitigation and adaptation.

II. Human Rights Law
Despite climate change impacting nearly every aspect of human well-being, the formal convergence of international climate change and human rights law is a recent development. These two legal domains arose from different historical and political contexts, leading to distinct normative paths. The treaty-based international human rights regime can be traced back to the Universal Declaration of Human Rights in 1948, facilitated by the post-World War II momentum. Conversely, the UNFCCC emerged four decades later in 1992. However, the formal interaction between human rights and climate change only took place in 2008, when the Human Rights Council adopted Resolution 7/23. The UNFCCC adopted human rights language two years later, in 2010.

Resolution 7/23, introduced in 2008, marked the first time a UN human rights body acknowledged climate change's impact on human rights. This resolution led to a comprehensive analysis by the Office of the UN High Commissioner for Human Rights (OHCHR) on the relationship between the two. The OHCHR report, submitted in 2009, highlighted the effects of rising global temperatures on specific human rights and groups. It also underscored the importance of procedural rights in addressing climate change, providing an early clarification on human rights obligations concerning climate change. Since then, numerous resolutions, studies, and discussions on the relationship between climate change and human rights have been adopted by the UN human rights system. Regional human rights systems, like the African and Inter-American Commissions, have also approved resolutions establishing the connection between human rights obligations and the need to prevent dangerous global warming.Some of these developments are indicated in the boxes below.

This expanding focus on human rights in climate change discourse has led to significant institutional and normative developments. For instance, in 2021, the Human Rights Council appointed a special rapporteurship to make recommendations on addressing and preventing climate change's adverse effects on human rights. Moreover, in July 2022, the UN General Assembly recognized the right to a clean, healthy, and sustainable environment, compromised by climate change, as a human right.

In parallel to international human rights law, the link between human rights and climate change has also evolved within climate change law, albeit at a slower pace. The COP to the UNFCCC first acknowledged this link at its 10th session in Cancún in 2010. However, a stronger emphasis came with the Paris Agreement, the first legally binding instrument to explicitly refer to human rights, despite the political tension that relegated human rights to a preambular reference.

The Paris Agreement represents a milestone for the integration of these two legal fields. As a result, policy and judicial efforts to mitigate and adapt to climate change increasingly aim to merge human rights and climate change frameworks. For example, the development of National Adaptation Plans under a human rights approach is gaining momentum as a strategy to advance specific human rights in high inequality contexts. Additionally, the Paris Agreement has triggered a surge in climate change lawsuits worldwide, using human rights arguments to urge national courts to redress climate-induced risks. In this respect, the IPCC has acknowledged the importance of climate-related litigation as a means to facilitate the implementation of mitigation and adaptation actions.

Conclusion
Climate change, one of the most complex challenges of our era, demands robust legal responses. This chapter has endeavored to provide an overview of the international climate change law primarily anchored on the UNFCCC regime. It has traced the historical background, structural blueprint, and normative propositions of the UNFCCC, aiming to delineate the pathways for the practical implementation of these written legal instruments.

However, the effectiveness and timeliness of these tools, as well as those emerging from the intersection of climate change law with other legal domains, remain critical questions in the prevention and adaptation to escalating global temperatures. The inescapable interlinkages between climate change and global inequality patterns underscore political and socioeconomic conflicts. Untangling these tensions is a prerequisite for achieving climate justice. As the law is a perfectible instrument, its adequacy in addressing climate change largely depends on our ability to prioritize a healthy planet over accumulation and dispossession.

Further Readings

 * Benoit Mayer, The International Law on Climate Change (1st edn, Cambridge University Press 2018).
 * Cinnamon Carlarne, Kevin R Gray and Richard Tarasofsky, 'International Climate Change Law: Mapping The Field' in Kevin R Gray, Richard Tarasofsky and Cinnamon Carlarne (eds), The Oxford Handbook of International Climate Change Law (Oxford University Press 2016).
 * Daniel Bodansky, Jutta Brunnée and Lavanya Rajamani, International Climate Change Law (Oxford University Press 2017).
 * Henry Jiménez Guanipa and Marisol Luna Leal (eds), Crisis climática, derechos humanos y los Acuerdos de París y Escazú. Crisis climática, transición energética y derechos humanos (Fundación Heinrich Böll 2020).
 * Jacqueline Peel, 'Climate Change Law: The Emergence of a New Legal Discipline' (2008) 32 Melbourne University Law Review 922.
 * Joyeeta Gupta, 'A History of International Climate Change Policy' (2010) 1 WIREs Climate Change 636 https://doi.org/10.1002/wcc.67.
 * Jutta Brunnée, 'Legal Argumentation in the Evolving Climate Regime' in Ian Johnstone and Steven R Ratner (eds), Talking International Law: Legal Argumentation Outside the Courtroom (Oxford University Press 2021) 239.
 * Katrina Fischer Kuh, 'International Climate Change Treaty Regime' in Karl S Coplan and others (eds), Climate Change Law: An Introduction (Edward Elgar Publishing 2021) 5.
 * Lavanya Rajamani and Jacob D Werksman, 'Climate Change' in Lavanya Rajamani and Jacqueline Peel (eds), The Oxford Handbook of International Environmental Law (2nd edn, Oxford University Press 2021) 492.
 * Rosemary Gail Rayfuse and Shirley V Scott (eds), International Law in the Era of Climate Change (Edward Elgar Publishing 2012).
 * Susana Borràs, 'Movimientos para la justicia climática global: replanteando el escenario internacional del cambio climático' (2016) 33 Relaciones Internacionales.