This article provides an introduction to the current international legal framework addressing climate change and tracks key stages in the framework’s development over the past 60 years.
Diving into the alphabet soup
The starting point was with the United Nations General Assembly (UNGA) passing of Resolution 1721(XVI) in 1961, which created various organizations with mandates to advance scientific knowledge on the physical causes of climate and significant weather alteration. In 1972, the UN Conference on the Human Environment in Stockholm, Sweden marked the first international environmental conference and resulted in the created the United Nations Environmental Programme (UNEP). The next decade saw the First World Climate Conference declaration identifying climate change as an urgent challenge, the creation of the World Climate Programme and, in 1979, the Convention on Long-Range and Transboundary Air Pollution (CLRTAP) becoming the first internationally legally binding instrument on climate. This was followed by United Nations Convention on the Law of the Sea (UNCLOS) in 1982.
In 1985 and 1987, the Vienna Convention for the Protection of the Ozone Layer and its related protocol (the Montreal Protocol) were adopted and opened for signature. In 1988, the Intergovernmental Panel on Climate Change (IPCC) was created. With 195 member states currently, the IPCC is the primary international authority on the state of scientific, technical and socioeconomic knowledge on climate change. Its reports are relied upon in formulating climate change policy, laws, and legal decisions.
From the late 1980s to early 1990s there were several other UNGA resolutions, international declarations, and statements which recognized a central theme of global communal responsibility in addressing climate change and acknowledged that human-induced greenhouse gas emissions (GHGs) are the primary cause of climate change. The Rio Summit in 1992 further established two additional legally binding conventions: the United Nations Framework Convention on Climate Change (UNFCCC), which entered into force in 1994 and is discussed below, and the Convention on Biological Diversity, which entered into force in 1993.
Important developments in the 1990s
United Nations Framework Convention on Climate Change
The UNFCCC currently has near-universal membership globally with 197 Parties. It has the overall goal of preventing “dangerous” human-induced (or ‘anthropogenic’) interference with the climate system in order to enable economic development without risking irreversible damage to the ecosystem and human health. It contains broad language that encourages a level of judgment and discretion based on evolving scientific, technical, and economic factors and knowledge. It was introduced to fill a gap by addressing all GHGs not covered by the Montreal Protocol.
The UNFCCC’s guiding principles are articulated in the preamble. Under international law, preambles are treated as an interpretive tool and are not binding. The UNFCCC accordingly codifies five distinct principles in Article 3, making them legally binding for Parties to use as guiding principles for their domestic implementation of the UNFCCC. For example, Article 3(3) articulates the ‘precautionary principle’, which states that notwithstanding scientific uncertainty about certain aspects of climate change, threats of irreversible damage to humans and the ecosystem should prevail as a priority.
Article 4 includes general and specific commitments that Parties must take into account. UNFCCC membership is categorized into separate Annexes, which places different obligations on industrialized and developing countries in recognition that industrialized countries are the primary source of GHG emissions and therefore should take more substantial measures to reduce their emissions. The general commitments that apply to all Parties include the obligation to keep track of their GHG emissions, implement an array of programs targeting climate change mitigation, and report on UNFCCC implementation measures taken. The reporting obligation is reviewed annually at the UNFCCC Conference of the Parties (COP); the authoritative decision-making body that negotiates new commitments based on the UNFCCC Parties’ reports and evolving knowledge on climate change.
1997 Kyoto Protocol
The Kyoto Protocol to the UNFCCC was adopted in 1997 to introduce more robust legally binding GHG emission reduction targets and timelines, which were absent from the UNFCCC. The Kyoto Protocol entered into force in 2005 and currently has 192 Parties.
The Kyoto Protocol’s general commitments for all Parties mirror those of the UNFCCC. But in alignment with the UNFCCC’s approach, specific commitments and targets apply to different Parties depending on categorization, with a view to encouraging Parties to develop national actions, policies, and measures, and to influence international market mechanisms. Developing country Parties, including some major emitters, do not have binding reduction targets under the protocol.
The 2000s (Pre-Paris Agreement)
In 2010, the 16th COP took place and resulted in the Cancun Agreements, one of which directly impacted the Kyoto Protocol by clarifying and confirming targets and mechanisms in the protocol, and raising standards for industrialized countries’ targets. In 2012, the Doha Amendment to the Kyoto Protocol introduced new GHG emission reduction targets for a particular Party category, revisited timelines for commitment periods, and introduced a new chemical to the list of GHGs covered under the protocol. With these amendments, developing country Parties still do not have binding reduction targets.
2015 Paris Agreement
The 2015 Paris Agreement falls within the UNFCCC framework and was negotiated during the 21st COP in Paris. It is the latest legally binding international treaty on climate change and came into force in 2016. It is viewed as a landmark treaty due to its ambitious goals and wide scope.
The overarching objective of the Paris Agreement is to limit global warming to under 2°C but ideally1 to 1.5°C, above preindustrial temperatures.
The Paris Agreement is organized to respect state sovereignty with a bottom-up structure of nationally determined contributions (NDCs), which allows Parties to communicate actions taken to reduce their own GHG emissions. To enforce accountability however, there are also structures in place including: a transparency system, which contains certain information sharing obligations under Articles 4 and 13; a global stocktake process, which begins in 2023 and involves collective progress tracking and assessment every five years under Article 14; and a compliance mechanism, which designates a committee to facilitate implementation and promotion of compliance under Article 15.
To settle disputes that may arise from Parties over the interpretation or application of the Paris Agreement, the UNFCCC dispute settlement provision applies. The UNFCCC provides the option for Parties to declare that they recognize prescribed arbitration procedures, to be adopted by the COP, as compulsory. These procedures have not yet been agreed upon and to date, only four Parties have made this optional declaration.
The language used throughout the Paris Agreement ranges from mandatory to more discretionary. For provisions pertaining to transparency and climate change mitigation, mandatory language is used (e.g., ‘shall’), which removes discretion from Parties. On the other hand, the language surrounding climate change adaptation measures is more permissive (e.g., ‘should’, ‘as appropriate’) and reads as recommendations instead.
The Paris Agreement is the first international environmental treaty that explicitly recognizes the link between climate change and human rights and, although non-binding, the preamble indicates that Parties should consider impacted human rights such as the right to life, right to health, and rights of particular vulnerable groups of people, such as Indigenous peoples, persons with disabilities, migrants, and children.
Paris Agreement Impacts
While implementation and the full potential and impacts of the Paris Agreement are yet to be seen, it has proven to be an increasingly-cited and persuasive piece of the international legal framework in climate change disputes, both against states and corporations. On the ground, many individual Parties have taken on their Paris Agreement obligations with more gravity, noticeably with the introduction and development of low-carbon alternatives in the power and transportation sectors.
The UNFCC’s 26th COP was delayed by a year from November 2020 to November 2021 as a result of the COVID-19 pandemic. This meeting was intended to resolve many aspects of the Paris Agreement’s implementation, including agreeing upon the aforementioned arbitration procedures to increase enforceability, carbon trading mechanisms and reporting time frames under the agreement.
Multilateral and regional environmental legal instruments
There are several legally binding multilateral environmental instruments in addition to the international legal framework discussed above. The multilateral instruments target specific areas of environmental concern that impact, or are impacted by, climate change.
These include wetland management, pollution from maritime shipping, air pollution, hazardous waste disposal, and biodiversity conservation. Regional instruments are in place and have been ratified in South Asia, Southeast Asia, and the Pacific. Several soft law instruments such as declarations have similarly been introduced multilaterally and regionally.
Other international legal regimes potential relevant to Climate Change
Human Rights instruments
International human rights law is being increasingly applied, in both the legal and policy context, in tandem with international climate change legal instruments. The argument made is that the impacts of climate change impact human health and wellbeing and are therefore also a matter of human rights (and other fundamental rights). Commentators tracking climate change disputes have been predicting (accurately) that there will be an increase in claims that are essential climate change related but formulated as human rights or other fundamental rights arguments.
At the forefront of international human rights law are the International Covenant on Civil and Political Rights (ICCPR) and the International Covenant on Economic, Social and Cultural Rights (ICESCR). Increasingly, commentators and activists are arguing that the many of the basic human rights legally binding international treaties are violated by climate change’s impacts, including the right to life, right to equality, right to an adequate standard of living, and the right to the highest attainable standard of physical and mental health.
For example, eight Torres Straight islanders submitted a complaint to the UN Human Rights Committee (UNHRC) against Australia, alleging that Australia’s failure to address climate change is a violation of their rights under the ICCPR. If successful, it would be the first international decision to hold that states have a duty to reduce emissions under human rights law. The UNHRC also held in a climate change refugee judgment that governments, under their international law obligations (e.g., the ICCPR), cannot return individuals to their country of origin where human rights, such as the right to life, would be at risk. UNHRC decisions are non-binding but are seen to exert political pressure on states seeking to demonstrate compliance with their international legal obligations.
There are further, more specific international human rights instruments that have obtained significant ratification by countries around the world. These are: the Convention Relating to the Status of Refugees, the Convention on the Elimination of All Forms of Discrimination against Women, and the United Nations Convention on the Rights of the Child (UNCRC). Famously, 16 children, including Greta Thunberg, filed a landmark complaint to the United Nations Committee on the Rights of the Child alleging that UNCRC Member States’ failure to tackle the climate crisis constitutes a violation of child rights.
Corporate Accountability instruments
In addition to human rights instruments, there are international corporate accountability instruments that are potentially relevant to climate change. While these instruments are not explicitly or exclusively designed to enforce climate change mitigation and adaptation measures against corporations, commentators and activists have argued that many of their mandates and provisions could relate to climate change.
Though non-binding in nature, the following two instruments in particular have been used as avenues through which stakeholders such as civil society organizations have sought to hold corporations accountable for their contributions to climate change or environmental damage. The first is the United Nations Guiding Principles on Business and Human Rights (UNGPs). These were cited by the by the Philippines’ Commission on Human Rights as conferring obligations on corporations to respect human rights when it announced, at COP 25 in 2019, its determination following a three year investigation that the 47 of the world’s largest fossil fuel companies, could be held legally liable for their contributions to climate change.2
The second is the OECD Guidelines for Multinational Enterprises (OECD MNE Guidelines), which are implemented through National Contact Point (NCP) offices. The NCPs are set up to hear complaints about companies that are allegedly in violation of the guidelines, facilitate discussion and mediation, and to provide recommendations to encourage compliance. Many complaints to countries’ NCPs in recent years, particularly in Europe, have been founded upon corporations’ impacts on climate change.
The UN Human Rights Council is currently developing an international binding treaty for business and human rights, which if implemented would be legally enforceable upon the activities of transnational corporations and other business enterprises. The treaty aims to achieve the goal of global mandatory human rights due diligence, something that has gained traction locally and regionally, especially in Europe.3
In 2021, in a landmark move, the Council recognised, for the first time, that having a clean, healthy and sustainable environment is a human right. In resolution 48/13, the Council called on states to work together and with other partners, to implement this newly recognized right. At the same time, through a second resolution, the Council also increased its focus on the human rights impacts of climate change by establishing a Special Rapporteur dedicated specifically to that issue.
Impact of the International Legal Framework
Across the world, the international legal framework surrounding climate change has had the effect of boosting global attention, driving political interest, and in some instances supplementing domestic legal and policy frameworks. Many governments are actioning their obligations under international law with more rigor as timelines for GHG emission reduction targets shorten. With international obligations being codified into national law, corporations operating under the jurisdiction of such governments are becoming subject to an increasingly stringent set of GHG emission standards and other statutorily mandated sustainability practices. Additionally, in recent years in climate change legal proceedings, both directed against states and corporations, the Paris Agreement, UNFCCC and human rights instruments are cited heavily in plaintiffs’ arguments and increasingly also referenced in court and tribunal decisions. Whether binding or not, these international instruments have had and will continue to have a significant impact on the legal and political landscape.
*With thanks to Christine Yan, Vancouver, for her contribution to this article.
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