Judicialization and legal implications of international maritime governance in the context of climate change: insights from ITLOS Advisory Opinion No. 31

Advisory Opinion in the ITLOS Case No. 31 represents the first climate change-related advisory proceeding brought before an international judicial body. It addresses key legal issues, including the advisory jurisdiction of the International Tribunal for the Law of the Sea (hereinafter referred to as the “ITLOS”) as a full court, the legal characterization of greenhouse gas emissions, and the relationship between the United Nations Convention on the Law of the Sea (hereinafter referred to as the “UNCLOS”) and the international climate change legal regime. This paper examines how the ITLOS established its advisory jurisdiction by relying on the doctrine of “necessity inference” and subsequently applied systemic interpretation as an interpretive method to bring greenhouse gas emissions within the scope of “marine pollution” under Article 1(1)(4) of UNCLOS. It further analyzes how, for the first time, the ITLOS systematically integrated UNCLOS with the United Nations Framework Convention on Climate Change and other environmental treaties to address legal gaps in the law of the sea regarding climate change and to promote greater coherence within the international legal framework. This study argues that the advisory opinion reflects a broader trend toward the judicialization of global climate governance by international adjudicative bodies and enhances the applicability of UNCLOS in the context of global environmental governance. However, it remains essential to maintain a balance between the expansion of jurisdictional powers of international adjudicative bodies and the legal obligations of States Parties.