My name is Donald Rothwell, and I am pleased to be your moderator for this panel on “Can Climate Change Litigation by Small Island States Address Their Goals?” The Grotius lecture last evening by Dame Meg Taylor gave the Society a tour de force of the governance, legal, and geopolitical issues confronted by small island developing states (SIDS) in the South West Pacific. A consistent theme throughout Dame Meg's lecture was the environmental challenges the region faced—ranging from nuclear weapons testing, colonial phosphate mining, IUU fishing, to climate change. Dame Meg gave us an insight into issues confronting small islands states in various parts of the world—whether it be the broader Pacific Ocean, the Caribbean, or the Indian Ocean. This panel has a particular focus on three current ongoing advisory proceedings which address climate change and international law generally, and more specifically some of the issues confronting small islands states. Those proceedings are before the International Tribunal on the Law of the Sea (ITLOS), the International Court of Justice (ICJ), and the Inter-American Court of Human Rights and small island states have actively promoted these cases going forward.
We have three speakers from diverse backgrounds and experiences in these matters and the approach we have agreed upon is to seek to tease out some of the key issues in a conversational format. I am joined on the panel by Sarah, Zachary, and Christina—their biographical details can be found in the meeting program app. I have four rounds of questions, and we are going to commence with a focus on science. To begin, we are going to focus on understanding the science behind the advisory opinion requests, and how the lawyers on the panel have been using the science to advance legal arguments. Sarah, perhaps we can start with an update on what the science is currently saying with respect to climate change and its impact on the marine environment, and especially its consequences for sea-level rise (SLR)?
The Intergovernmental Panel on Climate Change (IPCC) assessed that the global surface temperature increased 1.09° C between 1850 to 2019, caused by human-released greenhouse gases that trap solar heat. We also know that global mean sea surface temperature has increased since the beginning of the twentieth century by 0.88° C due to this overall planetary heat increase. This is causing mobile marine species to move toward the poles in search of comfortable temperatures. It is increasing the frequency and severity of marine heat waves, which can be lethal to species that cannot move, like warm water corals. Ocean warming has also been the major cause of sea-level rise since 1970. Sea-level rise is accelerating. The average rate of SLR from 1993–2018 was more than double the rate from 1901–1990. Ocean warming is also providing more power and moisture to storms.
The combination of sea-level rise and more severe storms is exponentially increasing the risk of catastrophic flooding in coastal zones. About 26 percent of human-released carbon dioxide has gone into the ocean and caused ocean acidification, which is a fundamental change in ocean chemistry that places stress on many marine organisms additional to what they are experiencing from heating or oxygen changes. The IPCC assessed with high confidence that every degree of additional warming beyond where we are today matters greatly. Looking ahead, the IPCC assessed climate risks to open ocean and coastal systems, and reported that ocean temperatures associated with a medium emissions scenario (where the best estimate global average temperature will be 2.7° C by end of century) would place estuaries, salt marshes, mangrove forests, seagrass meadows, kelp forests, sandy beaches, rocky shores, epipelagic, eastern boundary upwelling systems, and seamount systems at least at moderate risk by end of century, with warm water corals being at very high risk by then. In all scenarios, there is a 66–100 percent chance that the Arctic ocean will become practically sea ice free before 2050. The IPCC assessed that “ocean tipping points are being surpassed more frequently as the climate changes.” “Tipping points” are when marine systems undergo rapid changes that fundamentally alter the system and make it extremely difficult and unlikely for the system to return to its previous stable state. After tipping points are crossed, the new systems offer different opportunities and experiences to people than before, thereby heightening vulnerability for specific groups of people and economic sectors.
Donald Rothwell
Zachary, coming from the Caribbean, can you give us a sense of how these impacts are actually being witnessed by Caribbean island states?
The impacts are multi-faceted and while the more common impacts of hurricanes, storm surges, and the like are commonplace and are the most media-engaged, I want to also take this opportunity to highlight the long-term effects of these impacts as well. Broadly speaking, extreme weather events are slow on set events. Now with extreme events we have catastrophic damage. Damage that used to be rare, once in a decade, are now becoming the norm. Using two examples we see a Category 5 causes damage equivalent of one year's GDP in one day. According to the World Bank, Hurricane Maria in Dominica caused U.S. $1.3 billion or 224 percent of GDP worth of damage. That is the immediate aftermath, but there is also the recovery; humanitarian aid, which is not classified as climate finance, is sent in the immediate aftermath, but humanitarian aid does not allow for SIDS to rebuild in a sustainable way to prevent further damage. Many SIDS who are classified as middle to high income are then forced to seek loans to rebuild. And must then repay those loans in the aftermath of these catastrophic events, while, mind you, still remaining exposed to the very real risk of another Category 5 wiping out everything again. For example, Antigua after hurricane Irma estimated damage of U.S. $222 million according to the World Bank.
Those are just extreme weather events. Now if we also take a look at the slow onset events, like the systematic ocean temperature increase, ocean acidification, and rising sea levels, these events rarely receive humanitarian aid, because there is no “extreme event” moreover, these effects are more devasting. Over two hundred miles of the Belize barrier reef is now bleached. According to the World Wildlife Fund, the reef accounts for approximately 15 percent of the country's GDP and provides work for an estimated 200,000 people, how does one account for both direct and indirect ecosystem services lost as a result? In the Pacific Ocean, migratory species have started to change route. Some SIDS’ entire GDP rely on fishing and fishing related activities (licenses, etc.) For example, according to Conservation.org, ten pacific island states (Cook Islands, FSM, Kiribati, Marshall Islands, Nauru, Palau, Papua New Guinea, Solomon Islands, Tokelau, and Tuvalu) derive 4–84 percent of all government revenue from tuna alone. SIDS like Kiribati have actually started to relocate entire communities. When the ground itself is sinking beneath your feet, is this truly a disaster that needs aid, or is this a systematic crisis that requires the long-term thinking and coordinated action of states? We need to refrain from framing this crisis as a humanitarian aid issue because we end up missing key factors that need highlighting and addressing.
Donald Rothwell
Christina, what role has the science of climate change played in shaping argument in the advisory opinions (AOs)?
Science and the factual background of the devastating consequences of climate change is crucial to shaping legal arguments in both the ICJ and ITLOS advisory proceedings. Scientific evidence forms the factual background that guides the interpretation and application of the law. Former President of the ICJ, Judge Yusuf, has also observed that “[t]he law . . . and its application is, indeed, being influenced by scientific and technological changes”.Footnote 1
The applicable international treaties to these advisory requests put science at the center of the commitments and obligations set out therein:
• In the context of international environmental law:
◦ The UN Framework Convention on Climate Change (UNFCCC) recognizes that the “steps required to understand and address climate change will be . . . most effective if they are based on relevant scientific . . . considerations.”Footnote 2 Moreover, the temperature goal of 1.5° C above pre-industrial levels contained within the Paris Agreement is also based on the best available scientific evidence that it would “significantly reduce the risks and impacts of climate change.”Footnote 3
◦ Articles 200 to 206 of the UN Convention on the Law of the Sea (UNCLOS) create a legal regime that envisages a process of scientific study and research which determines the “appropriate scientific criteria” for the development of rules and standards on the prevention, reduction, and control of marine pollution.Footnote 4
• Article 5 of the World Heritage Convention provides for specific measures that states should aim to undertake for the protection of cultural and natural heritage, including, inter alia, taking appropriate scientific measures necessary for the “identification, protection, conservation, presentation and rehabilitation of th[e] heritage.”Footnote 5
In the climate change context, scientific evidence is relevant to both ascertaining the legal obligations and the responsibility for breaching those obligations. There are several aspects of scientific evidence that inform the determination of legal obligations. First, the science on the causes and effects of climate change, including on the climate system:
• The best scientific evidence as contained in the latest IPCC assessment report indicates that anthropogenic greenhouse gas (GHG) emissions have had and will continue to have devasting impacts on the climate system, including the atmosphere, the ocean, the cryosphere, the land surface, and the biosphere. Dr. Cooley herself gave a presentation during the oral hearings before ITLOS on the vast and dramatic impacts of climate change on the marine environment.
• In the context of international human rights, scientific evidence also establishes that climate change has caused catastrophic consequences for people of both present and future generations, impeding their enjoyment of fundamental human rights such as the right to life, the right to home, privacy, and family life, the right to health, the right to food, right to water, and the right of self-determination.
• The science also shows us the inherent inequality of climate change impacts. Least developed countries and small island developing states that have the lowest per capita emissions paradoxically have the highest vulnerability to climate change.
Science is also relevant to the question of applicable law—what legal principles and international treaties are relevant to states’ obligations of climate change given its wide-ranging impacts?
• The answer is a wide body of law: international environmental law because of its impacts on the environment, human rights law because of its impacts on the enjoyment of human rights, the law of the sea because of its impacts on the marine environment, and even the law governing cultural and natural heritage because of its impacts on world heritage. And there can be other applicable principles and instruments.
Science also informs the content of a legal obligation. It has been argued that states have a due diligence obligation with respect to the harms caused by climate change, but what exactly does this standard entail? Based on the best scientific evidence, limiting the increase in global temperatures to 1.5° C as contained in the Paris Agreement is the minimum necessary to avoid the worst of the climate crisis.
Finally, science is relevant to assessing loss and damage. Source attribution science, which traces the origin of the pollutants that cause climate change, and quantifies their role in driving climate impacts, may allow the apportionment of which GHG contribution causes which damage. This aspect of science is relevant to the attribution of state responsibility as well as the calculation of loss and damage.
In sum, science is relevant to all aspects of the advisory proceedings because it goes to facts, legal obligations, the content of the standard, and to loss and damage.
Donald Rothwell
The panel is now going to move to a focus on the ITLOS advisory opinion and especially the role of small island states in promoting the ITLOS AO, and legal arguments that were advanced in those proceedings. Zachary, the ITLOS AO was instigated by the Commission of Small Island States on Climate Change and International Law (COSIS), can you discuss for us the background to that request and issues arising with respect to the Advisory jurisdiction of ITLOS?
Zachary Phillips
COSIS was created as an international organization with the goal in mind of representing small island states in international legal fora. You can say that ITLOS was the first effort toward achieving this goal. And specifically, the impact of climate change on the ocean is a central element of COSIS's mandate with references made throughout its preamble, mandate, and activities as highlighted in the COSIS Agreement. For example, in Article 2(1), the Agreement provides that COSIS's activities shall include: “Assisting small Island states to promote and contribute to the definition, implementation and progressive development of rules and principles of international law concerning climate change, in particular the protection and preservation of the marine environment, including through the jurisprudence of international courts and tribunals.”
Thus, COSIS became a specific vehicle for SIDS to cooperate on a global basis to contribute to the rules and principles of international law concerning climate change. Now, we had the vehicle, where should it go. Part of the COSIS structure is a team of legal experts from various areas of the team, practices, and cultures. The membership at the time in consultation with the legal experts thought that strategically it would be beneficial to request an AO from the ITLOS as COSIS's first activity for several reasons.
The obvious linkages between climate issues and the ocean and the very deleterious effects SIDS face due to the slow-onset effects and due to the siloing effect mentioned above, it is difficult to find which “room” is the “right room” to negotiate and address these outcomes. The legal framework of the UNCLOS also has more clear provisions on obligations we felt, the only issue was whether anthropogenic activities could fall under the scope of the obligations listed therein. Thus, we felt this exercise would benefit SIDS and an added benefit would of course be that this AO would feed in directly into the ICJ AO.
As it relates to issues to the advisory jurisdiction. We would say there are no issues. The Tribunal has already confirmed and clearly outlined that it has an advisory opinion and what are the criteria for accessing it, in the Request for an Advisory Opinion Submitted by the Sub-Regional Fisheries Commission (SRFC). While there were some states who did not agree and, in fact, made oral and written submissions to share their disagreement. However, this is a concluded point as far as we are concerned. In SRFC, the Tribunal stated that the competence is derived from Article 21 of its Statute. Additionally, they outlined the requirements for conducting advisory opinions: (1) an international agreement related to the purposes of the Convention specifically provides for the submission to the tribunal of a request for an advisory opinion; (2) the request must be transmitted by a body authorized by or in accordance with the agreement mentioned above; and (3) such an opinion may be given on a legal question. COSIS met all of those requirements.
Donald Rothwell
Christina, this AO involved an unprecedented thirty-four written submissions from states, and nine from intergovernmental organizations, followed by ten days of oral hearings in September 2023. Can you comment on some legal arguments that were advanced by various states?
Christina Hioureas
In both the written and oral proceedings, several important legal issues were addressed. Whether the obligations under the Law of the Sea Convention can be interpreted to cover climate change in light of the scientific consensus on climate change? Note the context that UNCLOS does not expressly contain the term “climate change” because at the time the treaty was being negotiated and ratified, there was not a complete picture of the science as we understand it today. There was a consensus among states and organizations that based on the best scientific evidence, anthropogenic GHG emissions constitute “pollution to the marine environment” within the meaning of UNCLOS, thus bringing the issue of climate change within the Convention's ambit. It was widely agreed that scientific evidence is crucial to informing the interpretation of the definition of “pollution to the marine environment”—a term that was adopted when the international community did not have the same awareness of climate change and its consequences, including impacts on the marine environment.
There was also the question of what the obligation of due diligence that is required to protect and preserve the marine environment entails for states in respect of climate change. The obligation to protect and preserve the marine environment under UNCLOS, including the obligation to prevent, reduce, and control marine pollution, is a due diligence obligation. Many states argued that the Tribunal must take into account other relevant rules, principles, and standards, including those contained in other instruments, in ascertaining the content of this due diligence obligation. These include rules and principles contained in the UNFCCC, the Paris Agreement, and the Convention on Biodiversity Beyond National Jurisdiction Agreement.
Accordingly, the obligation of due diligence under UNCLOS requires states to take all necessary measures, collectively and individually, to limit the increase in global average temperature to 1.5° C as required by the Paris Agreement. Some states even argue that the due diligence obligation requires going beyond the 1.5° C temperature goal, because there are still risks of significant harm to the marine environment at that standard. In discharging their due diligence obligation, states must also have constant regard to the best scientific evidence on climate change in adopting and assessing the effectiveness of their measures to protect and preserve the marine environment.
The principle of common but differentiated responsibilities featured prominently in the proceedings. Obligations must be assessed in light of the context that certain states have contributed less and have more limited capabilities.
Sierra Leone argued, and this was my portion of the argument as counsel on that team, that the obligation of states to preserve and protect the marine environment in relation to climate change must be accompanied by a recognition of the wide margin of appreciation enjoyed by states under customary international law to regulate in the public interest. If states are obligated to take steps to curb climate change, there must be a recognition of the right to regulate. ITLOS has the opportunity to affirm that principle in the context of climate change to fight against ISDS claims when taking steps to phase out coal-fired power plants or other measures designed to comply with the Paris Agreement. We have seen claims brought against Italy, Germany, the Netherlands, Senegal, and others arising from their efforts to comply with the obligations laid out in the Paris Agreement.
Donald Rothwell
Sarah, what are your reflections as to the role climate and marine science played in those submissions?
Sarah Cooley
I was intrigued to see that most submissions did not contest the idea that heat and carbon dioxide constituted pollutants to the marine environment. Certainly, as an IPCC author, I feel the science is settled and the evidence shows that heat and carbon dioxide do have harmful effects on marine systems, just like other pollutants. But as an American who has seen all sorts of climate science denial arguments, I found it refreshing to see that this particular piece of evidence seems not to be in question. To me it seems as though the IPCC aim of providing policy-relevant, but not policy-prescriptive information, succeeded here. The IPCC reports have established the amount and effect of heat and carbon dioxide going into the marine environment. This leaves other questions to be decided focusing on jurisdictions and social system responses.
Donald Rothwell
In this round we move to a focus on the separate ICJ AO proceedings, and the Inter-American Court AO proceedings and how they may develop throughout 2024. Christina, what role has international human rights law played in the ICJ AO?
Christina Hioureas
It plays a central role. The chapeau to the questions posed by the General Assembly specifically referenced human rights instruments (Universal Declaration of Human Rights (UDHR), International Covenant on Civil and Political Rights (ICCPR), International Covenant on Economic, Social and Cultural Rights (ICESCR)) as well as the right of future generations. The human rights aspect therefore is crucial to the ICJ AO request, also demonstrating the difference in scope between the various climate change advisory opinion requests. There are a number of human rights implicated by climate change: life, home, private and family life, health, water, food, self-determination, cultural life, and development. This connects to the question about science which shows the devasting impacts of climate change on the enjoyment of human rights:
• Damage to the food system caused by climate change has been shown to cause famines and droughts, leading to humanitarian crises.
• Extreme weather events destroy homes, displace communities, and threaten human lives.
• Disruptions to key livelihoods, especially in more vulnerable states and communities, e.g., fishing and agriculture.
• Entire countries are literally disappearing, sometimes losing not only their ancestral homelands but potentially their entire sovereign territory.
It is thus important to think of the climate crisis also as a human rights crisis, so a human rights perspective is important when we frame our submissions to the ICJ:
• Loss and damage: climate reparations and damages for human rights violations associated with climate change.
• Damage to cultural heritage sites or disruptions to cultural and ancestral traditions, particularly for Indigenous peoples whose traditions and identities are often linked to land.
• Maritime boundaries: right to sovereignty over wealth and natural resources is a component of the right to self-determination.
The question is of course how to apply international human rights law to climate change given that the majority of human rights instruments do not expressly govern or address climate change. A proper interpretation of the obligations under these instruments must take into account existing legal frameworks and principles as well as the best available scientific evidence on climate change. The Vienna Convention on the Law of Treaties (VCLT) Article 31(1) provides that a “treaty shall be interpreted in good faith in accordance with the ordinary meaning to be given to the terms of the treaty in their context and in light of its object and purpose.” The ordinary meaning of the relevant provisions of the UDHR, ICCPR, and ICESCR is intentionally broad and wide in scope, and sets out comprehensive protection of human rights. Nothing in the ordinary meaning of these provisions suggests that the obligations they codify cannot be breached by climate change-induced impacts. The object and purpose of these human rights instruments accord with the idea that they encompass climate change, including the obligation to “secure [the] universal and effective recognition and observance [of human rights]” that “derive from the inherent dignity of the human person.” Finally, the principle of systemic integration under Article 31(3)(c) of the VCLT requires taking into account “any relevant rules of international law applicable in the relations between the parties.” Such rules also aid in bringing the human rights dimension into the fold of interpreting the obligations of states with respect to climate change.
It is therefore hoped that the Court will issue an advisory opinion clarifying and confirming the obligation to address climate change as a human rights obligation. The implication of this would be that not only states but also individuals can hold other states accountable for failure to take mitigation and adaptation measures in respect of climate change.
Donald Rothwell
Zachary, can I ask you to comment on how Antigua and Barbuda approached these particular advisory proceedings?
Zachary Phillips
On the Inter-American Court of Human Rights (IACtHR), we are represented by COSIS. On behalf of COSIS, the position we take is that the IACtHR is in a unique role, as the only human rights court requested to render an advisory opinion on climate change, the Court can provide a targeted perspective on states’ human rights obligations with respect to the climate emergency. Starting with the science as always, there is a clear link to climate catastrophes and what actions must be taken to limit the impacts. Inaction on the parts of states to prevent these catastrophizes in our view is a failure in of itself. However, the human rights perspective adds more weight to the condemnation of this inaction by highlighting that states are under specific obligation under the Convention with respect to all convention rights affected by the climate emergency. Therefore, states must ensure that activities within their jurisdiction or control do not cause harm to the environment of other states. To achieve this the duty of international cooperation (Article 26) must be engaged as well as the duty to prevent harm, which should all be informed by due diligence principle on the best available science.
On the ICJ, we are both represented in the COSIS submissions, and we have submitted national submissions. The two submissions are consistent, however achieve the same goal in slightly different approaches. COSIS takes the approach of highlighting the customary rules of international law that require more action from states, such as duty to prevent harm for example, whereas in Antigua and Barbuda's national submissions we made an attempt to highlight the common obligations across the different treaty regimes, to again portray this idea that siloing obligations is not practically useful and where slight nuances exist, we highlight that states are not meeting either obligation due to the lack of adherence to the principle of due diligence, which we say should be informed by the best available science.
Donald Rothwell
Sarah, these advisory opinion requests are much broader in scope than the ITLOS AO and extend to climate science in general. Based on your knowledge how has that shaped some of the submissions that have been developed?
Sarah Cooley
Scientists have a much better ability in the last decade to attribute observed outcomes in the marine ecosystem to climate drivers. Scientists also have better ability to attribute the contributions of individual states or even multinational corporation to climate drivers. It is particularly true for heat and ocean acidification. Attribution of other outcomes is much less clear. This ability to follow the evidence using the science gives people much greater ability to discuss how responsibility should be apportioned, for causing climate impacts, and how remedies should be designed accordingly. It is fascinating for me to be part of the progression: science lines up the evidence, like a detective establishing “who, what, where, when, and how.” This enables discussion of “what next,” which is a social question that requires participation of many perspectives, especially given the worldwide impacts of locally based actions.
Donald Rothwell
In this final round I am going to ask for reflections from the panel as to the significance of the three AOs, and where the outcomes of these AOs over the next year may take international law, the rights and interests of small island states, and the significance of climate science in international law. Sarah, please answer from a climate science perspective.
Sarah Cooley
I am most familiar with the UNFCCC climate policy process and how climate science informs that. I have heard some chatter from that side about how these AOs are an attempt at sidestepping the UNFCCC's work of international climate goal-setting via nationally determined contributions (NDCs) and its work toward creating loss and damage funds to support countries affected most by climate change. But while the UNFCCC process is well intentioned, it is slow. And lately I believe more lip service has crept in by nations that hold positions of power. Nevertheless, we are also seeing really effective coalitions of small nations, low-income nations, ocean-focused nations, and others come together to have a more unified and loud voice in the UNFCCC policy process.
I would love it if the AO decisions would at a minimum underscore the importance and urgency of designing equitable solutions that support nations most affected by climate impacts. I do not know enough to speculate whether the AO decisions might also begin to lay out a path to identifying or implementing the most equitable solutions. If so, maybe that could be faster than the UNFCCC negotiations toward loss and damage. Certainly, climate science will continue to play a role first in identifying just “how good” proposed climate solutions are for the ocean—both in terms of affecting the climate and providing beneficial outcomes for marine ecosystems and dependent people. And second, in attributing the effects of specific countries’ actions to them. Here, climate science plays the part of being a forensic detective to accumulate the facts. It is up to the judicial system to decide how to proceed with that evidence.
Donald Rothwell
Zachary, please answer from a small island state perspective.
Zachary Phillips
So many ways to address this question, I will answer from different aspects of my reality as a youth SIDS national who also works in the field of diplomacy and international law. Starting with my experience from practice, I think a major significance of these advisory opinions will be the reversal of this tendency we have to silo regimes into their own distinct entities that do not seem to engage with one another. I have been in negotiation rooms on different areas, and it is almost territorial “this is a trade issue, this is human rights,” etc. I surely do not suggest that competencies and expertise are not important, however, this staunch exclusionism does not support the interest of SIDS for two reasons:
Firstly, a lot of issues are intersectional. Look at my example regarding hurricanes, that raises implications for climate issues and for debt sustainability issues.
Secondly, for many SIDS our capacity is severely limited, we do not have experts in each field employed at the government to follow the several sub-issues at the World Trade Organization and the several sub-issues at the conferences of the parties (COPs) to make sure that we can raise our interests in every single siloed sub-room. It is usually the same small team that follow several areas and as the ones experiencing the brunt of the crisis we see firsthand how the climate crisis interplays with the several rights and obligations under multiple regimes, and yet we are not allowed to speak on it. I hope that stops.
As a young man from an island who has witnessed the drastic change in landscape, temperature, weather patterns, and ultimately the very viability of life, it would be remiss of me not to mention that I have wondered about the future of my home and what kind of life my children will have. In that vein, I hope that the AOs aid in the strengthening of the principle of prevention and duty of due diligence in the actions of states and non-state actors. As I have said, at the heart of this is climate justice, is it fair that through no fault of the actions of SIDS, and whilst the agreed science has confirmed the risks and projected outcomes for decades now, that my nation along with many others shall simply disappear or at best be caught in a cycle of destruction and rebuilding?
I think the climate science is clear (and has been clear for a while) and I believe that with these AOs they will more directly be linked the enforcement of the principle of prevention and the customary international law principles of the duty of due diligence and the duty of international cooperation.
Donald Rothwell
Christina, please answer from a general international law perspective.
Christina Hioureas
There is no silver bullet here, and a multi-pronged approach, with cooperation between all states, is essential. The advisory opinions that we await from the Courts are just a few tools that we can use in this effort. With respect to the potential legal path, I want to address the risk of fragmentation in international law and the potential for convergence. There is a risk when three different tribunals are considering overlapping issues, but the Courts can hopefully look to each other to some extent—while they are not bound by the preceding opinions of the other Courts, they can take them into account. States’ wide participation and consistency in terms of the positions being articulated is key to bring to the various courts’ attention overlapping issues that they need to take into account. Moreover, the obligations being invoked in these proceedings come from a variety of sources: international environmental law, customary international law, human rights law, and the protection of cultural property. This creates an opportunity for consistency across treaties, as opposed to fragmentation, precisely because of the various sources of law being considered in assessing the obligations of states with respect to climate change and the content of those obligations.
These advisory opinions create an exciting opportunity. Ten years ago, we were concerned about fragmentation, and here we are before three different tribunals considering how a variety of sources of law are implicated in one issue: climate change.
In terms of leveraging the opinions, as a matter of law, advisory opinions are not binding, but they do “carry great legal weight and moral authority” according to the ICJ. ICJ advisory opinions have been invoked as precedent in later cases, for instance in the Mauritius v. Maldives maritime boundary case before ITLOS, where the Chagos advisory opinion was cited as evidence that the Chagos archipelago was part of the territory of Mauritius and ITLOS accepted this argument. This is one of many examples of subsequent tribunals relying on advisory opinions in making binding determinations.
In the climate change context, the hope is that the advisory opinions can help clarify state obligations and will be used in subsequent litigation by SIDS and other developing countries, whether at the international or domestic level. If ITLOS issues an advisory opinion finding that states have obligations to protect and preserve the marine environment in respect of climate change, we may see interstate cases under UNCLOS. This is because UNCLOS provides for a compulsory dispute settlement mechanism for disputes concerning the interpretation and application of the convention. Under Article 287, disputes can be heard by ITLOS, ICJ, or an Annex VII arbitral tribunal. This mechanism is compulsory for all state parties—absence of a party is not a bar to the proceeding as occurred in South China Sea and Arctic Sunrise. Claims could relate to failure to comply with the Paris Agreement's temperature goals, failure to have regard to the best scientific evidence in adopting mitigation and adaptation measures, or issues of transboundary harm when damage happening in one part of the world has catastrophic consequences elsewhere. It will be interesting to watch this space and see if interstate cases before ITLOS pull from the advisory opinion.
Generally, outside the context of UNCLOS, states can also make claims on behalf of individuals for violation of human rights obligations before the ICJ or other bodies. This is particularly likely to happen under human rights instruments with compulsory dispute settlement provisions, such as the Convention on the Elimination of All Forms of Discrimination Against Women (CEDAW). Optional protocols to human rights treaties ratified by many states also enable individuals to bring claims before UN treaty enforcement bodies. Litigation by individuals before domestic courts against states regarding the latter's obligations to mitigate and adapt to climate change is another avenue. There is also the hope, as expressed by Sierra Leone in the ITLOS proceedings, that the advisory opinions could be invoked by states in response to investment claims brought in response to their efforts to phase out coal-fired power and take other steps aimed at complying with the Paris Agreement, underscoring the margin of appreciation that they enjoy to regulate in the public interest. States further have the opportunity to invoke these advisory opinions in their interventions and negotiations before the UN. And in addition to these legal and diplomatic avenues, we are also providing our politicians one more piece of law to cite when taking domestic measures aimed at curbing GHG emissions.
