Laws of the seas

The United Nations Convention on the Law Of the Sea (UNCLOS)

The UNCLOS is an international agreement that provides guidelines for nations regarding their rights and responsibilities regarding their use of the world’s seas and their natural resources. This convention was open for signature in 1982 and in force in 1994. As of today, 168 countries and the European Union have joined the convention. The convention aim to codify international laws regarding maritime boundaries and the applying legislation, international navigation (Part III), protection of marine environment (Part XII), marine scientific research (Part XIII), development and transfer of marine technology (Part XIV) and settlement of disputes in a peaceful manner (Part XV).

Maritimes boundary of the UNCLOS

Simplified illustration of the maritime boundaries and the national and international rights.

Internal waters

This zone delimits the waters on the landward side of the baseline, a line that follows the low-water line of the state. The state has full sovereignty over the airspace above and the water column, seabed, and subsoil below. More information on the internal waters can be found in Part II of the UNCLOS.

Archipelagic waters

Archipelagic State may draw its baseline by joining the outermost points of the outermost islands, therefore creating an area called Archipelagic Waters. The state has full sovereignty over the airspace above and the water column, seabed, and subsoil below. More information on the archipelagic waters can be found in Part IV of the UNCLOS.

Territorial waters

This zone may not extend beyond 12 nautical miles from the baseline.The coastal state has full sovereignty over the airspace above and the water column, seabed, and subsoil below. Ships of all states (coastal or land-locked) have a right of innocent passage in the territorial waters, as long as it takes place in conformity with the UNCLOS and with other rules of international law. More information on the territorial waters can be found in Part II of the UNCLOS.

Contiguous Zone

This zone may not extend beyond 24 nautical miles from the baseline. The coastal state controls compliance with customs, fiscal, immigration or sanitary laws and regulations, and may also punish infringements committed on its territory or territorial waters. More information on the contiguous Zone can be found in Part II of the UNCLOS.

Exclusive Economic Zone

This zone may not extend beyond 200 nautical miles from the baseline. The coastal state has sovereign rights to explore, exploit, conserve and manage the living and non-living natural resources of the water column, seabed, and subsoil. It also has rights on other activities: energy production (water, current, wind); establishment and use of artificial islands, installation and structure; marine scientific research; protection, and preservation of marine environment…However, all states (coastal or land-locked) have freedoms of navigation, overflight, laying of submarine cables and pipelines, and some other internationally lawful uses of the sea. More information on the EEZ can be found in Part V of the UNCLOS.

Legal Continental Shelf

The coastal state has sovereign rights to explore and exploit mineral and non-living resources of the seabed and subsoil as well as sedentary species (organisms that, at harvesting stage, are immobile or under the seabed or move in constant contact with seabed or subsoil). Coastal states can ask for an extension of their legal continental shelf, this may not extend beyond 350 nautical miles from the baseline or shall not exceed 100 nautical miles from the 2,500 meter isobath (a line connecting the depth of 2,500 meters), whichever is greatest. This extension will be reviewed by the commission on the limit of the continental shelf (CLCS) to confirm the outer limit submission. More information on the continental shelf can be found in Part VI of the UNCLOS.

High Sea

This area is beyond national jurisdiction, all states (coastal or land-locked) have freedoms of navigation, overflight, laying of submarine cables and pipelines, construction of artificial islands and other installations permitted under international law, fishing and of scientific research. These freedoms shall be exercised in regard to other states’ interests and the rights under the UNCLOS. More information on the High seas can be found in Part VIII of the UNCLOS.

The Area

This area and its resources are humanity’s inheritance and is limited to the mineral resource part of the seabed and subsoil that lie beyond national jurisdiction. No state can claim or exercise sovereignty or sovereign rights over the Area. It is administered by the international seabed authority. More information on the Area can be found in Part XI of the UNCLOS.

Legal steps for a country to claim extended continental shelf area

The french maritime domain

Thanks to its overseas departments and territorial authorities scattered over three oceans, France has the second Exclusive Economic Zone (EEZ), behind the United States, which is not part of UNCLOS. The french EEZ represent 10 165 095 km2, which represent 8% of the world wide EEZ surface, when the terrestrial superficy of France is only 0,45% of the emerged land. Considering the terrestrial and maritime superficy France is considered the 6th largest country in the world with less than 10% of that superficy in Europe.

Since the 12 of June 2020 the CLCS aurorized France to extend its continental shelf by 151.323 km2 which added to the first extension in 2015 represents 730.000 km2. This sums up to an area of sovereignty over the seabed of more than 1million km2. In order to obtain this extension France already spent around 21millions euros between 2003 and 2009, which is less than some other countries, for instance, Canada would have spent 100millions euros and Danemark 40millions euros (More information).

The French authorities pointed out in a press release, while the exploitation of these submarine areas is not on the current agenda, this new extension enables France to preserve its rights for the future in vast submarine areas, which implies the possibility of ensuring their protection if exploitation is not desired.

Have fun comparing countries between their land and maritime territories. You might be surprised!

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The Continental shelf

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