Bringing climate change into the realm of UNCLOS: the ITLOS Advisory Opinion

On 21 May 2024, the International Tribunal for the Law of the Sea delivered its unanimous Advisory Opinion on Climate Change, issued at the request of the Commission of Small Island States on Climate Change and International Law. This landmark Advisory Opinion represents a significant development in international law, offering critical clarification of the specific obligations of States Parties to the United Nations Convention on the Law of the Sea to address the impacts of climate change on the ocean and to protect and preserve the marine environment in this context. This article examines the Tribunal’s approach to jurisdiction and discretion, the integration of the best available science and the interpretation of the Convention in relation to external rules. It further provides a detailed analysis of the specific obligations incumbent on States Parties, with particular emphasis on the ‘necessary measures’ that they are required to take pursuant to the Convention. This article demonstrates that the Advisory Opinion reaffirms the status of the Convention as a living instrument, capable of adapting to and addressing evolving environmental challenges.