The ITLOS Advisory Opinion on Climate Change and Marine Pollution: Some Reflections

Abstract

This case note provides a critical overview of the International Tribunal for the Law of the Sea's (ITLOS) 2024 advisory opinion on the legal obligations of States under UNCLOS concerning climate change and marine pollution. Rather than a comprehensive review, this note highlights and analyzes the major legal principles and implications arising from the Tribunal's interpretation, focusing on its significance for international environmental and maritime law. This new approach helps to close the gap between the development of international maritime law and the inclusion of environmentally related agreements. The advisory opinion outlines some of the principles of international law such as due diligence and precaution which elevate the responsibilities of States to prevent and minimize climate-caused adverse impacts on the marine environment. This review analyzes this landmark case and its overall significance from a critical perspective; although the opinion is not legally compulsive it has strong legal and moral weight which offers a strong foundation for the future development of litigation policies and treaties.

Introduction

International environmental law has developed considerably in recent decades, particularly in reaction to the increasing threats posed by a changing climate to the marine environment. The United Nations Convention on the Law of the Sea (UNCLOS), adopted in 1982, mainly focused on marine pollution caused by conventional sources, such as shipping and oil tankers. ¹ However, as knowledge from science accrued on climate change caused by humans, it became increasingly clear that human-induced emissions from greenhouse gases (GHGs) and their impact on the ocean (e.g., warming, sea-level rise, and acidification) resulted in a different and novel type of marine pollution a type with unprecedented urgency. ^{2 , 3} Although the 1990s marked a growing recognition of climate change as a global threat, the connection between atmospheric pollution and oceanic health was notably assessed with respect to the legal framework of the sea. ⁴

Gradually, multilateral treaties, such as the Kyoto Protocol (1997) and the Paris Agreement (2015), started to acknowledge more general impacts of climate change without translating these into the framework of international law on marine pollution. ⁵ The ITLOS advisory opinion of May 2024 is a landmark step forward, opening the option of interpreting the definition of marine pollution as found in the UNCLOS to also encompass the effects of anthropogenic GHG emissions. This view is indicative of a growing understanding that climate change is inextricably linked to marine health, and a significant move towards reconciling the ocean contamination law of old with the new-age requirement of climate action in marine spaces. Its assimilation by the Tribunal of climate change effects within the scope of marine pollution denotes a “paradigm shift” in the way international law will deal with the crossover of ocean governance and climate change in the years to come.

The present note offers an analytical summary of the landmark advisory opinion issued by ITLOS in May 2024. While not exhaustive, this paper emphasizes the Tribunal's key legal determinations, particularly the expansion of the definition of marine pollution to include greenhouse gas emissions and the application of due diligence and precautionary principles. The objective is to elucidate the opinion's broader impact on international law and climate governance, especially for vulnerable Small Island Developing States (SIDS). It provides guidance and a definition of the responsibilities of States to the UN Convention on the Law of the Sea concerning the impacts of climate change on the marine environment. This request, raised by the COSIS, is divided into two broad areas. First, atmospheric GHG emissions that are causing ocean warming, acidification, and sea level rise can be broadly termed marine pollution within the provisions of UNCLOS. Second, what are the specific legal requirements expected of States to protect and conserve the marine environment from these effects? This opinion is of great importance to SIDS because these nations are most vulnerable to the impacts of climate change, such as an increase in sea levels, an increase in ocean acidity, and a decline in marine resources. The ITLOS advisory opinion is a positive development in the use of existing international legal systems in the face of new and growing international challenges.

However, it not only enhances the legal framework for dealing with climate change's consequences on the ocean but also sets the groundwork for subsequent legal activities and legislation. It paraphrases the two questions posed to ITLOS

“What are the specific obligations of State Parties to the United Nations Convention on the Law of the Sea (‘UNCLOS’), including under Part XII:

(a) to prevent, reduce, and control pollution of the marine environment in relation to the deleterious effects that result or are likely to result from climate change, including through ocean warming and sea level rise, and ocean acidification, which are caused by anthropogenic greenhouse gas emissions into the atmosphere?

(b) to protect and preserve the marine environment from climate change impacts, including ocean warming and sea level rise, and ocean acidification?”

Proceedings of the Case

This case was filed on 12 December 2022 by the COSIS, and the request was not directed to any particular state but sought to establish the duties of State Parties in connection with marine pollution due to greenhouse gas emissions, under the UNCLOS. At first filing written statements from 31 State Parties and several organizations were recorded and oral hearings were conducted in September 2023. The Tribunal considered two main questions: whether greenhouse gas emissions can be considered as marine pollution under UNCLOS to the extent of the States’ responsibilities to prevent harm to the marine environment. Consequently, on May 21, 2024, ITLOS announced its advisory opinion.

Analysis of the ITLOS Opinion

The ITLOS advisory opinion represents a development in international environmental law, as it brings for the first time the effects of anthropogenic greenhouse gas (GHG) emissions within the core activities linked to marine pollution. As a matter of history, marine pollution law played a critical role under the framework of the UNCLOS, mainly in regulating traditional sources of pollution such as oil pollution, waste from ships, and chemicals. This pollution had effects on marine ecosystems, which were physical, observable, and took effect right away. ⁶ Climate is clicking in. Until now, climate change-related impacts, including ocean warming, acidification, and sea-level rise, represent a novel and more intractable challenge that was largely missing from earlier maritime governance. ⁷

The Tribunal's judgment mirrors a mature vision of transboundary marine pollution as a dynamic, interdependent reality. By acknowledging the direct implications of climate change on oceans’ health, ITLOS has expanded the definition of marine pollution to cover the cumulative impacts of GHG emissions, gases that are emitted principally into the atmosphere, with devastating and long-term impacts on the marine environment. ⁸ This acknowledgment is consistent with the precautionary principle of international law, which calls for precautionary measures when dealing with uncertain but possibly devastating environmental damage. To begin with, the incorporation of GHG emissions into the definition of marine pollution is an important leap toward bringing climate change considerations within the purview of the law of the sea, which was lacking in the case of climate-induced harm.

A key theme of the ITLOS opinion is the invocation of UNCLOS's general clauses to stretch legal responsibilities concerning marine pollution to include climate change. More specifically, the interpretation of Part XII of UNCLOS (Protection and Preservation of the Marine Environment) by the Tribunal is of major importance. The opinion places a responsibility on States not only to prevent and control pollution of the marine environment from traditional activities, but also the environmental harm resulting from international activities, such as the burning of fossil fuels and deforestation, leading to GHG emissions. ⁹

This wider interpretation has important legal implications for climate litigation. The ITLOS advisory opinion is expected to be a reference to other cases in which the link between air pollution and the degradation of the marine environment is crucial. It opens the door for States and non-state actors to potentially file lawsuits against countries or companies accelerating climate change through the world's oceans in the future under the law of the sea. States most susceptible to sea-level rise and ocean acidification could also use this opinion to bring the world's biggest carbon emitters before international courts or tribunals. This may also spur new legal innovations around States’ responsibility under international environmental law for regulating emissions and taking climate measures that more effectively protect the marine environment.

This opinion is an important step towards the fusion of the maritime law and climate policy. It recognizes the interrelation between land-based emissions and the marine environment, serving as a separate basis for future multilateral conventions that cover both climate change and the marine environment in a unitary manner. As the oceans continue to gain attention as an aspect critical to climate, in terms of being a carbon sink and as a recipient of damage due to carbon, this opinion further adds to the understanding of the interconnectedness needed for successful international climate governance.

Interpretation of UNCLOS Provisions

The Tribunal's expansive interpretation of “marine pollution” under UNCLOS Article 1(4) signifies a landmark jurisprudential development. By encompassing anthropogenic greenhouse gas emissions, ITLOS acknowledges indirect but profound environmental impacts such as ocean warming and acidification. ¹⁰ This teleological approach aligns with the Vienna Convention on the Law of Treaties’ principles (Articles 31–32), emphasizing UNCLOS's object and purpose to robustly protect the marine environment. This shift bridges gaps between traditional maritime law and contemporary climate governance, underscoring the adaptive capacity of international law in the face of evolving environmental challenges. The ITLOS advisory opinion provided a fundamental interpretation of some major provisions of UNCLOS, especially those under part XII, which deals with the legal regime on the protection and preservation of the marine environment. ¹¹ Foremost was the understanding that climate change-related effects such as warming of the seas, sea-level rise, and ocean acidification are within the definition of marine pollution under UNCLOS. ¹² According to Article 1(4), pollution involves substances or energy introduced into the marine environment that has, or is likely to have a harmful effect. ¹³ The Tribunal widened this definition by deeming atmospheric greenhouse gas (GHG) emissions as this type of pollution if its impacts are being received in marine environments. The Tribunal bases its conclusion on Article 192, which states an overall requirement for States to ensure the conservation and maintenance of the marine environment. This duty, while general in nature, is backed up by the more specific provisions of Article 194, which calls upon States to take measures to prevent, reduce, and control pollution of the marine environment. ITLOS underlined that this obligation not only requires the prevention of direct pollution by discharges from ships but also indirect and transboundary pollution sources, including emissions arising from human activities. Such a broad definition of marine pollution is perhaps seen as a shift in the application of the UNCLOS. Earlier, the provisions of the Convention were used for less spatially and temporally diffuse sources of pollution. By applying these obligations to atmospheric emissions with downstream marine impacts, the Tribunal showed that it was willing and able to look forward to future situations to give meaning to the treaty. The above approach complies with the Vienna Convention on the Law of Treaties, especially Articles 31 and 32, which furnish interpretation based on the object and purpose of a treaty. ¹⁴ ITLOS also highlighted that the principal objective of UNCLOS is to protect the marine environment therefore using the treaty to regulate the emission of GHG-related pollution is within the treaty's scope. ¹⁵

Definition of Pollution

One of the legal changes is the fact that the Tribunal has included GHG emissions as marine pollution. In this case, historically, the term pollution under UNCLOS has been understood primarily in terms of actual substances that are thrown into the sea. The advisory opinion pointed out that resulting phenomena such as ocean acidification and warming are direct outcomes of human-induced emissions, fulfilling the definitional criteria of pollution as defined in Article 1(4). ITLOS also reaffirmed the principle of systematic integration as a recognized principle of international law. Systematic integration enables the harmonization of treaties and legal regimes to respond to the interrelated issues of globalization. The Tribunal's interpretation connected the UNCLOS obligations to the further international undertakings under the UNFCCC and the Paris Agreement, giving importance to the connection between the atmospheric and marine surroundings. ¹⁶

Principle of Due Diligence

The ITLOS opinion also restated the principle of due diligence as one of the foundational principles of States’ obligations under UNCLOS. ¹⁷ In due diligence, the States are supposed to ensure and use all measures possible to ensure that activities under their jurisdiction or control do not have adverse impacts on the marine environment. ¹⁸ The Tribunal stated clearly that this obligation is not one concerning the achievement of a particular result but is process-oriented regarding States. States must take action in anticipation of climate change by passing legislation that governs the actions of private actors and engaging in international cooperation to address the effects of climate change. ¹⁹ This obligation was indicated by the Tribunal as having been derived from Article 194, particularly paragraphs 1 and 2, which states that States have to prevent, reduce, and control pollution from any source and to ensure that activities within their jurisdiction do not cause harm to other States. ITLOS frames due diligence as a process-based standard, focusing on the obligation of States to adopt and enforce reasonable measures to prevent harm. ²⁰ This procedural emphasis reflects the realities of scientific uncertainty in climate change governance and promotes flexible yet accountable State behavior. The Tribunal's approach resonates with established international environmental law principles and jurisprudence, reinforcing the role of due diligence in regulating activities with potential transboundary impacts.

Due diligence and precaution are among the basic components of international law, notably in environmental law. Such principles have important implications for state responsibility and behavior to avoid environmental harm, particularly in the case of climate change and marine pollution. ²¹ Traditionally, the evolution of these principles was triggered by the need to ensure States not only refrain from causing harm that exists already or in the immediate future but also allow them to take preventative actions even if scientific information about potential harm is equivocal or even missing.

Due Diligence in Environmental Law:

The due diligence principle demands that States take reasonable precautions to prevent damage to the environment, particularly if it has transboundary implications. This principle has been widely used in environmental protection litigation, especially by the international courts. ²² The States are required to behave responsibly under UNCLOS, meaning they have to ensure that activities under their jurisdiction and control do not damage the marine environment of other States (Article 194). This understanding was corroborated by the ITLOS advisory opinion, where it was accepted that States are compelled to take due diligence to prevent long-term climate-related harm to marine ecosystems. Whereas the application of due diligence has traditionally been limited to localized pollution sources, the ITLOS opinion broadens it to global GHG emissions and the contribution of States to global environmental impacts. ²³

In the ITLOS advisory opinion, the Tribunal specifically mentioned the duty of due diligence in UNCLOS and the precautionary principle as “key” in accommodating (increasing) risk related to climate change. By extending the definition of marine pollution to address the global consequences of GHG emissions, the Tribunal stressed that States were not just required to curb domestic sources of pollution, but also to prevent pollution that crosses frontiers. This is an important issue for international cooperation, and the carbon footprints and responsibilities of developed nations emitting the most climate-related impacts on the marine environment. ²⁴

Precautionary Principle in the Context of Climate Change:

According to the precautionary principle, where action threatens serious or irreversible environmental damage, lack of scientific certainty should not be used as a reason for postponing measures to prevent that damage. This principle is particularly relevant in marine pollution resulting from climate change. ²⁵ The ITLOS opinion is guided by the ‘precautionary principle. A recognition that climate change impacts (including ocean acidification, rising sea levels, and coral bleaching) present intractable threats to marine biodiversity and ecosystems, even in the face of scientific uncertainty about the specifics of those impacts. The Tribunal's finding is in line with a fast-evolving consensus that climate change's uncertainty cannot be used to prevent states from acting right away to avert further damage to the marine environment.

Applying this principle, the Tribunal invited the States to act in a precautionary way, even if scientific knowledge is not completely certain, in order to avoid damage to the marine environment from climate change. It emphasizes that combating climate change is not the exclusive responsibility of States affected by its immediate effects due to global warming, but an obligation shared by all States requiring joint action. The manner the precautionary approach is adapted to climate-related marine pollution by ITLOS underscores the importance of early action in connection with the adoption of measures to protect the marine environment against climate-related pollution and the associated transition to green energy.

Broader Implications for International Law:

This integration in the ITLOS opinion of due diligence and precaution means a major change in international environmental law addressing climate change. Such values are fundamental to a future in which States are legally required to take account of the long-term consequences of their actions upon the global environment. The ITLOS advisory opinion's extension of these principles to marine pollution will be key for establishing a remedy in climate litigation. It is divisive, and how carefully precautions are taken raises questions about government responsibility and legal grounds for addressing the impacts of climate change through laws protecting the ocean. These principles are critical to prodding the global community toward enacting strong climate laws for reducing emissions, taxing carbon, and managing the oceans sustainably. The ITLOS advisory opinion therefore opens avenues for a more holistic and comprehensive approach to addressing international environmental problems, including marine pollution, biodiversity depletion, and climate change, that emphasizes prevention rather than cure, and that takes place at both the national and international levels.

Precautionary Principle

The precautionary principle was also used by the Tribunal as one of the major considerations. ITLOS also appreciated that climate change is a very complicated and uncertain issue, and thus, much care needs to be taken in the protection of the environment. ²⁶ This principle means that States have to do something to eliminate the risk, even when science is not conclusive. ²⁷ ITLOS also stressed that under UNCLOS, the duty of safeguarding the marine environment is proactive, and the precautionary approach contributes to this task; the tribunal's approach to the precautionary principle is progressive in its application of UNCLOS. The Tribunal's invocation of the precautionary principle strengthens the preventive mandate of UNCLOS, compelling States to act in the face of scientific uncertainty. ²⁸ This principle, foundational in international environmental law, encourages proactive measures to avert irreversible marine harm. By endorsing precaution, ITLOS reinforces the normative expectation that States must not await full scientific certainty before acting to protect vulnerable marine ecosystems.

The Paris Agreement and UNFCCC

The ITLOS advisory opinion highlights the relationship between UNCLOS and other major international legal instruments dealing with climate change, especially the United Nations Framework Convention on Climate Change (UNFCCC) and the Paris Agreement. In its judgment, ITLOS was keen to stress that the measures required by Part XII of UNCLOS are consistent with the aims of the Paris Agreement especially Article 2 (1) (a) of the agreement which aims at keeping global temperature rise below 2°C. In so doing, ITLOS strengthened obligations placed on States to decrease emissions under both legal regimes by incorporating atmospheric GHG emissions as a form of marine pollution. ²⁹ This integration enhances the practical rationality of the system by preventing States from avoiding their obligations under the one regime by claiming that they are exclusively governed under the other. The Tribunal also dealt with the question of whether climate change impacts are combined and cross-border. This approach is cognate with the principles of equity and CBDR under the UNFCCC. ITLOS's opinion embraces the principle of systematic integration by aligning UNCLOS obligations with the UNFCCC and Paris Agreement. ³⁰ This promotes legal coherence across overlapping treaty regimes addressing climate change and marine protection. While reinforcing the complementary nature of these frameworks, the Tribunal also implicitly highlights the complexities of operationalizing this integration, particularly regarding enforcement and jurisdiction.

Human Rights Dimensions

Although human rights are not mentioned in UNCLOS, the ITLOS opinion incorporates them through the lens of the adverse effects of climate change on vulnerable groups, especially SIDS. The tribunal understood that the destruction of the marine environment and its resources poses a direct risk to the well-being of food sources and the indigenous identities of coastal populations. In affirming the state's obligation to avoid and minimize climate-induced marine pollution, the opinion indirectly supports the protection of human rights. Although UNCLOS does not explicitly address human rights, the Tribunal's emphasis on protecting SIDS inherently invokes human rights considerations. ³¹ This reflects a growing jurisprudential recognition of the interdependence between environmental integrity and human rights, particularly for populations disproportionately affected by climate change. This integration advances climate justice discourse within the maritime legal context. ³²

Comparative Analysis

The advisory opinion given by the ITLOS on climate change and marine pollution is an important judgment in international environmental law. Its importance is, however, better understood when placed in relation to other landmark climate-related cases such as the Urgenda case and the IACtHR advisory opinion. ³³ The Urgenda case in the Netherlands Supreme Court forced the government of the Netherlands to cut GHG emissions to meet the requirements of the ECHR. ³⁴ The court provided caution to the right to life and the right to family life of the citizens of the country. The ITLOS opinion adds to this by pointing out the commitments under UNCLOS regarding the protection of the marine environment against emissions of GHG. While Urgenda focused on domestic obligations, ITLOS considered the impacts of climate change specifically as they relate to common concerns such as the ocean. The IACtHR advisory opinion associated environmental deterioration with human rights under the American Convention on Human Rights. ³⁵ It declared that States have to avoid transboundary harm for the preservation of fundamental rights. Even though ITLOS did not have recourse to human rights as a legal argument, it approached similar issues. It also focused on the impact of climate change, pointing out SIDS that largely rely on the marine environment. As for the IACtHR, the opinion was about the States’ responsibilities to protect individuals from risks that stem from other countries. ITLOS, on the same note, discussed the crosscutting effects of GHG emissions but framed its discussion under UNCLOS. ³⁶ This is due to the fact that ITLOS has specialized in the marine environment in providing its technical legal analysis. ICJ has also dealt with environmental requirements in suitable cases, such as the Pulp Mill on River Uruguay (2010) and certain Activities Carried out in the Border Area (2015). ³⁷ The ICJ underlined the preventive approach with reference to the environmental impact assessments (EIAs) in order to prevent transboundary harm. ³⁸ Although ITLOS did not demand EIAs, it emphasized the need for preventive steps under UNCLOS, reiterating similar measures. The Inter-American Court of Human Rights, in its Advisory Opinion OC-23/17, elaborated on the intrinsic relationship between environmental protection and the enjoyment of human rights. The Court underscored that environmental harm, particularly from climate change, threatens fundamental rights such as the right to life, health, and access to water, thereby establishing that States have obligations to prevent environmental degradation that adversely affects human rights. This opinion has been influential in reinforcing human rights dimensions within environmental jurisprudence, complementing the ITLOS advisory opinion's implicit recognition of vulnerable populations such as SIDS. ³⁹

Potential Challenges and Limitations of ITLOS Advisory Opinion

One of the main drawbacks of the ITLOS Advisory Opinion is that it cannot have any binding force; unlike some of the other decisions, it does not place direct legal obligations on States, but it does bear legal and moral force. This limitation is a disadvantage regarding the application of the opinion since the actual implementation of the guidance that is provided in the opinion depends on the political will of States and their preparedness to bring their policies into conformity with the decision of the Tribunal under UNCLOS. Although advisory opinions may guide future treaty negotiations, state practice, and judicial decisions, their non-binding nature could limit the ability of immediate implementation or enforcement.

Although in ITLOS's decision, it was stated that GHG emissions fit into the definition of marine pollution based on UNCLOS, the Court did not elaborate on how States should perform this duty. The opinion stresses national legislation and international cooperation, but it gives no guidance on the rules of how to fulfill such commitments in detail. ⁴⁰ This uncertainty raises questions for States, especially the least developed or those without adequate legal and technical capacity, about what they need to do to meet their obligations under UNCLOS. Second, the opinion does not contain a clear mechanism for the participation of non-state actors, which are corporations and industries, major emitters of GHG.

While the opinion helps to fill some gaps between UNCLOS and other international treaties such as the Paris Agreement, it does not create a clear system for how these regimes can be aligned. Climate change is a combination of many factors and must be tackled through cooperative networks of several international legal systems. However, the ITLOS opinion does not elaborate on how multiple and cumulative UNCLOS obligations and other treaties and agreements should be implemented and coordinated.

One major drawback of the opinion is the financial and technical ability of many States, especially SIDS and developing countries, to put into practice the measures proposed. Although ITLOS stressed the principles of international cooperation, it did not discuss how financial or technical assistance can be provided to those States that do not possess enough resources to meet the requirements of UNCLOS. This omission reduces the practical utility of the opinion, as many vulnerable States depend on assistance from others to mitigate the effects of climate change on the marine environment. The lack of suggestions on how these funding mechanisms will be developed or where the capacity-building initiatives will be sourced points to a more fundamental structural weakness of international law.

Implications of ITLOS Advisory Opinion

The advisory opinion of ITLOS has the potential to shape the future of international law, global climate policy, and the future of vulnerable nations. It enhances legal instruments in combating climate change and brings about crucial concepts that may define future legal and policy change. ITLOS recognized these risks and underlined that States have the legal responsibility to safeguard the marine environment under UNCLOS. This recognition strengthens SIDS’ capacity to mobilize for international partnership and funding, especially in the UNFCCC and in the negotiations of the Paris Agreement. The opinion also broadens international environmental law by correlating atmospheric and marine pollution. In this case, ITLOS interpreted GHG emissions as marine pollution, thus offering a legal framework for addressing transboundary harm under UNCLOS. The above opinion from the ITLOS may shift the global climate policy as it will strengthen the call for an integrated approach. This way, ITLOS showed how the two treaties, the UNCLOS and the Paris Agreement, can complement each other in approaching the difficult questions of the global environment. Such a model of systematic integration gives a guide on how to enhance the coherence of interconnections between legal systems and the coherence of their approaches to global challenges such as climate change.

Conclusion

The ITLOS advisory opinion of 2024 marks a significant jurisprudential shift in international environmental law, extending the definition of “marine pollution” under UNCLOS to encompass anthropogenic greenhouse gas (GHG) emissions and their cascading impacts on marine ecosystems. By recognizing phenomena such as ocean warming, acidification, and sea-level rise as legally actionable forms of marine degradation, the Tribunal affirms the interdependence of atmospheric emissions and oceanic health, transforming a long-recognized scientific linkage into a legal obligation for States. Through its interpretation of Articles 1(4), 192, and 194 of UNCLOS, the Tribunal reaffirms the core environmental principles of due diligence and precaution, compelling States to take anticipatory, evidence-informed actions, even amid scientific uncertainty. This interpretation, grounded in the object-and-purpose approach of the Vienna Convention on the Law of Treaties, reflects a commitment to the adaptive evolution of treaty law in response to emerging global challenges. Importantly, ITLOS aligns UNCLOS with the normative aims of the UNFCCC and Paris Agreement, reinforcing a trend toward systemic legal coherence across overlapping regimes—mirroring developments in international jurisprudence such as Urgenda and the IACtHR Advisory Opinion OC-23/17.

The Tribunal's emphasis on the disproportionate risks faced by SIDS implicitly engages with the growing rights-based discourse on environmental harm. While UNCLOS does not explicitly enshrine human rights, the opinion resonates with evolving legal recognition of the right to a healthy environment, particularly as affirmed by regional courts and international soft law instruments. This connection underscores the human consequences of marine degradation—food insecurity, livelihood displacement, and cultural erosion—and supports an emerging norm of climate justice for vulnerable populations. However, the advisory nature of the opinion under Article 138 of the ITLOS Rules limits its immediate enforceability. The lack of detailed implementation pathways, particularly for capacity-constrained States, and the absence of mechanisms to address corporate environmental accountability expose enduring structural gaps in global environmental governance. These limitations may hinder short-term impact, especially where political will or institutional support is weak.

Though the opinion establishes a persuasive legal interpretation that may shape customary international law through its influence on state practice, judicial reasoning, and treaty development. It affirms the capacity of international law to adapt to diffuse and transboundary harms, and positions ITLOS as a central forum for clarifying State obligations in the climate-ocean nexus. In doing so, the Tribunal has laid a foundational step toward integrating climate accountability into the legal framework of ocean governance, one that is likely to resonate in future litigation, policy formulation, and treaty negotiations.