The continental shelf may extend to a distance of 200 miles from the baselines or, if the continental margin extends beyond that limit, to the outer edge of the continental margin as defined by the Convention. The regime of the continental shelf applies to the sea bed and subsoil and does not affect the status of the superjacent waters or airspace.
The regime of the high seas applies seaward of the EEZ; significant parts of that regime, including freedom of navigation and overflight, also apply within the EEZ. The sea-bed beyond national jurisdiction, called the Area in the Convention, comprises the sea-bed and subsoil beyond the seaward limit of the continental shelf.
Internal Waters
Article 8(1) defines internal waters as the waters on the landward side of the baseline from which the breadth of the territorial sea is measured. This definition carries forward the traditional definition of internal waters found in article S of the 1958 Geneva Convention on the Territorial Sea and the Contiguous Zone, 15 UST 1606, TIAS No. 5639, 516 UNTS 205 (Territorial Sea Convention). The importance of baselines and the rules relating to them are discussed in the next section.
Territorial Sea
Article 2 describes the territorial sea as a belt of ocean which is measured seaward from the baseline of the coastal State and subject to its sovereignty. This sovereignty also extends to the airspace above and to the sea-bed and subsoil. It is exercised subject to the Convention and other rules of international law relating to innocent passage, transit passage, archipelagic sea lanes passage and protection of the marine environment. Under article 3, the coastal State has the right to establish the breadth of its territorial sea up to a limit not exceeding 12 miles, measured from baselines determined in accordance with the Convention.
The adoption of the Convention has significantly influenced State practice. Prior to 1982, as many as 25 States claimed territorial seas broader than 12 miles (with attendant detriment to the freedoms of navigation and overflight essential to U.S. national security and commercial interests), while 30 States, including the United States, claimed a territorial sea of less than 12 miles. Since 1983, State practice in asserting territorial sea claims has largely coalesced around the 12 mile maximum breadth set by the Convention. As of January 1, 1994 128 States claim a territorial sea of 12 miles or less; only 17 States claim a territorial sea broader than 12 miles.
Since 1988, the United States has claimed a 12 mile territorial sea (Presidential Proclamation 5928, December 27,1988). Since the President's Ocean Policy Statement of March 10, 1983, the United States has recognized territorial sea claims of other States up to a maximum breadth of 12 miles.
Contiguous Zone
Article 33 recognizes the contiguous zone as an area adjacent to the territorial sea in which the coastal State may exercise the limited control necessary to prevent or punish infringement of its customs, fiscal, immigration, and sanitary laws and regulations that occurs within its territory or territorial sea.
Unlike the territorial sea, the contiguous zone is not subject to coastal State sovereignty; vessels and aircraft enjoy the same high seas freedom of navigation and overflight in the contiguous zone as in the EEZ. The maximum permissible breadth of the contiguous zone is 24 miles measured from the baseline from which the breadth of the territorial sea is measured.
In 1972, the United States claimed a contiguous zone beyond its territorial sea (historically claimed as 3 miles) out to 12 miles from the coastal baselines (Department of State Public Notice 358,37 Federal Register 11,906). Since 1988, when the United States extended its territorial sea to 12 miles, the U.S. contiguous zone and territorial sea claims have thus been coterminous. Under the Convention, the United States could set the seaward limit of its contiguous zone at 24 miles, enhancing its ability to deal with illegal immigration, drug trafficking by sea and public health matters.
Exclusive Economic Zone (EEZ)
The establishment of the EEZ in the Convention represents a substantial change in the law of the sea. The underlying purpose of the EEZ regime is to balance the rights of coastal States, such as the United States, to resources
Figure 1. The Legal Regimes and Geomorphic Regions
