ITLOS Advisory Opinion on Climate Change
INTRODUCTION
On 21 May 2024, the International Tribunal for the Law of the Sea (ITLOS) issued its landmark Advisory Opinion on Climate Change and International Law, the first of a series of advisory opinions on climate change across various judicial fora (see also ICJ and IACHR). The Opinion was requested by the Commission of Small Island States on Climate Change and International Law (COSIS), which presented the Tribunal the following questions:
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 in relation to climate change impacts, including ocean warming and sea level rise, and ocean acidification?
The ensuing Opinion is remarkable for several reasons. Not least because it is the first instance in which an international court or tribunal has addressed the issue of climate change from the perspective of the law of the sea. However, the significance of this Opinion extends beyond its novelty. Indeed, ITLOS lived up to its reputation as a progressive Tribunal, as it boldly interpreted the provisions in the UN Convention on the Law of the Sea (LOSC) on pollution expansively as to encompass greenhouse gas (GHG) emissions, thereby rendering the comprehensive regime on marine pollution applicable to climate change. Bolstered by state-of-the-art scientific insights, the Tribunal strongly endorsed the objective to limit global temperature increase to 1.5°C above pre-industrial levels, found that States are under an obligation to restore marine habitats and ecosystems, and recognized the importance of the ocean as “the world’s largest carbon sink”, among other significant findings.
Spanning an impressive 153 pages, the Opinion addresses a plethora of issues, ranging from fisheries and marine protected areas to geoengineering and environmental impact assessments. This series of blogs takes a deep dive into selected issues addressed by the Tribunal. Endalew Lijalem Enyew and Mazyar Ahmad assess the Tribunal’s findings on the notion of ‘common but differentiated responsibilities and respective capacities’, and technical assistance through a TWAIL lens. Two blogs will look at how the Tribunal dealt with questions relating to how LOSC is nested within its wider legal context: Bastiaan Klerk takes a closer look at the interrelationship between the Paris Agreement and LOSC, and Ellen Hey looks at how the Tribunal dealt with other relevant instruments. Richard Barnes will provide an assessment of how ITLOS addressed the contentious issues of its jurisdiction and discretionary power. Finally, Vito De Lucia will scrutinize the obligation of ‘restoration’ as part of the preservation of the marine environment.
Through this series, which will be published on a rolling basis over the course of the coming montchs, we aim to elucidate the implications of the ITLOS Advisory Opinion for the further development of international law, as well as for future jurisprudence in the realm of climate change and the law of the sea. The series of blog posts on the specific issues covered by the Tribunal are as follows:
- Endalew Lijalem Enyew and Mazyar Ahmed, “ITLOS’s Advisory Opinion on the notion of ‘common but differentiated responsibilities’ to protect the marine environment from climate change: A closer look from the Standpoint of developing States”.
- Bastiaan Klerk, “To Lex Specialis, or not to Lex Specialis? The Paris-UNCLOS Nexus in the ITLOS Advisory Opinion on Climate Change”.