UNCLOS: International Law, Maritime Boundaries, and Ocean Governance

The United Nations Convention on the Law of the Sea (UNCLOS) was adopted at the Third Conference on the Law of the Sea in 1982, after eight years of negotiation. The convention seeks to provide a comprehensive regime of rules governing the use of oceans and their resources. Considered one of the foundational documents in international law, it was adopted by 130 votes in favor and 4 against, with 17 abstentions. The convention came into force twelve years after its adoption (Article 308 of the convention provides that “the Convention shall enter into force 12 months after the date of deposit of the sixtieth instrument of ratification or accession”—that is, when states inform the United Nations that they're now parties to the Convention), partly after amendments to Part XI of the Convention (dealing with the Area) in July 1984. As of February 3, 2017, the convention has 168 state parties, including the European Union. Notable states that have not ratified the convention include the United States of America and Turkey. Today, much of UNCLOS is considered to reflect customary international law, meaning that all states are bound to the convention’s principles irrespective of whether they are parties to the convention or not.

Part I sets the definitions adopted in the convention as well as its scope of application. Part II focuses on the territorial sea and contiguous zone. It starts by clarifying the legal status of the territorial sea, the airspace over that sea, and the seabed and subsoil. It also deals with the limits of the territorial sea, importantly highlighting the breadth and outer limit of the same and how these are to be calculated depending on the different coastal features, including reefs, internal waters, ports, and roadsteads. The territorial sea shall, under Article 3 of the convention, not exceed 12 nautical miles. Part of the limitations ascribed to territorial waters is the right of innocent passage, meaning that ships are entitled to pass through the territorial waters as long as that passage is not prejudicial to the peace, good order, or security of the coastal state. Part II, Section III is dedicated to the elaboration of this right of innocent passage.

Part III addresses straits used for international navigation, focusing on their legal status, transit passage, and innocent passage therethrough. Part IV focuses on archipelagic states, Part V addresses the Exclusive Economic Zone (an area that extends 200 nautical miles from the baseline within which the coastal nation has exclusive rights to exploit the natural resources), and Part VI addresses the continental shelf. Part VII deals with the high seas, espousing principles such as the freedom of the high seas, rights of navigation, and the exclusive jurisdiction of the flag state on vessels navigating these waters. It also regulates the conservation and management of the living resources of the high seas. The following parts cover the regime of islands (Part VIII), enclosed or semi-enclosed seas (Part IX), and the right to access of landlocked states to and from the sea and their own freedom of transit (Part X).

The area defined as “the seabed and ocean floor and subsoil thereof, beyond the limits of national jurisdiction” is the subject of Part XI. The area and its resources are the common heritage of mankind; their use must be for the benefit of mankind and only for peaceful purposes. A seabed authority is set up under Section 4 of this part, so that state parties can organize and control activities in the area, particularly with a view to administering the resources of the area.

Part XII deals with the protection and preservation of the marine environment, an issue that is now topical given changes to the acidity of the oceans as a result of CO₂ pollution. It sets out rules on the prevention, reduction, and control of pollution and addresses the need for global and regional cooperation to this end and the enforcement of the relevant rules. Part XIII deals with marine scientific research, highlighting the right to conduct such research, international cooperation in this area, conduct and promotion of such research, and the rights of land-locked and geographically disadvantaged states. Part XIV addresses the issue of development and transfer of marine technology. Finally, in Part XV, the convention deals with the dispute settlement mechanism, providing states with a range of options, including the International Tribunal on the Law of the Sea, the International Court of Justice, or international arbitration (provided for in Annex VII).

Across these articles, the convention addresses a broad spectrum of issues relevant to the world’s oceans, from sovereignty to shipping, from environmental concerns to dispute settlement. It is very much intended to be a “constitution for the oceans.”

FURTHER READING: Anderson, D. H. 2008. Modern Law of the Sea: Selected Essays. Leiden, The Netherlands: Brill. Barrett, J. and R. Barnes. 2016. Law of the Sea: UNCLOS as a Living Treaty. London: British Institute of International and Comparative Law.

United Nations Convention on the Law of the Sea. 1982. http://www.un.org/depts/los/convention_agreements/convention_overview_convention.htm. Accessed March 14, 2018.