“Breaking Boundaries: International Court Declares States Have Legal Duty to Protect Oceans from Climate Change”

The International Tribunal for the Law of the Sea (ITLOS) made history on May 21, 2024, by becoming the first international court to declare that States have a legal duty to protect the oceans from the drivers and impacts of climate change. In its landmark advisory opinion, ITLOS confirmed that greenhouse gas emissions are a form of marine pollution that States must prevent, reduce, and control. This decision clarifies the obligations of State Parties to the United Nations Convention on the Law of the Sea (UNCLOS) in the context of the climate emergency, going beyond the requirements of the United Nations Framework Convention on Climate Change (UNFCCC) and the Paris Agreement.

The process leading up to this historic decision began in 2022 when the Commission of Small Island States on Climate Change and International Law (COSIS) requested an advisory opinion from ITLOS. This coalition of Small Island Developing States (SIDS), which are among the most vulnerable to the impacts of climate change despite contributing the least to it, sought clarification on State obligations to prevent, reduce, and control anthropogenic greenhouse gas emissions and protect the marine environment from related harms.

Over fifty States, international organizations, and civil society organizations participated in the advisory proceedings, providing written submissions and oral interventions. The significance of this advisory opinion extends beyond ITLOS, as it is expected to guide future decisions on climate and international legal duties by the Inter-American Court of Human Rights and the International Court of Justice.

Key elements of the ITLOS advisory opinion include the recognition that anthropogenic greenhouse gas emissions constitute pollution of the marine environment, requiring States to take all necessary measures to prevent, reduce, and control such pollution. States must adhere to a stringent standard of care guided by the best available science, with a focus on the 1.5°C temperature limit outlined in the Paris Agreement. The opinion emphasizes that the Paris Agreement does not exclusively define State obligations in relation to climate change, and all States are duty-bound to take action to reduce greenhouse gas emissions.

The ITLOS advisory opinion also highlights the importance of a precautionary approach, conducting environmental impact assessments, and avoiding risky technological interventions in addressing climate change. While the opinion represents a significant step forward in climate accountability, there are opportunities for further progress in future advisory opinions and climate litigation at national and regional levels.

Overall, the ITLOS advisory opinion underscores the critical role of international law in advancing climate justice and protecting the oceans and atmosphere for the benefit of all humanity. As Prime Minister Gaston Browne of Antigua and Barbuda stated, safeguarding these global commons is a matter of life and death for marine ecosystems, coastal communities, and the planet as a whole.