what is Functions of the Law of the Sea?

professor Tanaka said, The law of the sea plays a dual role in international relations.
First, the primary function of international law involves the spatial distribution of jurisdiction of States, and the same applies to the law of the sea. The contemporary international law of the sea divides the ocean into multiple jurisdictional zones, such as internal waters, territorial seas, the contiguous zone, the exclusive economic zone (EEZ), archipelagic waters, the continental shelf, the high seas and the Area, i.e. ‘the sea-bed and ocean floor and subsoil thereof, beyond the limits of national jurisdiction’. In principle, the law of the sea provides the rights and obligations of a coastal State and third States according to these jurisdictional zones. Consequently, the law seeks to coordinate the interests of individual States. This approach is sometimes called the zonal management approach. Considering that the world is divided into sovereign States, the traditional role of the law of the sea will in no way lose its importance.

Second, given that the ocean is one unit in a physical sense, the proper management of the oceans necessitates international cooperation between States. In general, the spatial scope of man-made jurisdictional zones does not always correspond to marine ecosystems. In fact, several species, such as straddling and highly migratory species, do not respect
artificial delimitation lines. The divergence between the law and nature is a serious deficiency in the traditional zonal management approach. International cooperation is thus a prerequisite for conservation of marine living resources as well as biological diversity. Similarly, without international cooperation, the regulation of marine pollution would be less effective because pollution may spread beyond maritime boundaries. Furthermore, a single State’s regulation of industrial activities to prevent marine pollution would put that State’s economy at a competitive disadvantage. International cooperation is also needed in marine scientific research due to the highly complex nature of the oceans. The law of the sea provides a legal framework for ensuring international cooperation in marine affairs, thereby safeguarding the common interests of the international community as a whole.

These two basic functions – the spatial distribution of national jurisdiction and ensuring international cooperation between States – are not mutually exclusive, but must coexist in the law of the sea.

source: The International Law of the Sea, Yoshifumi Tanaka