Chapter 3 UNCLOS and the Promotion of Oceanographic Surveys
(1) Oceanographic Surveys to Demarcate Jurisdictional Sea Areas
JMSA has always been responsible for conducting accurate surveys of Japan's main coastal regions and promoting the collection and compilation of basic data on low-water lines, etc., to determine baselines of the territorial sea for measuring the breadth of Japan's territorial sea, etc.
Furthermore, in FY 1992, when it became apparent that UNCLOS would come into effect in the near future due to the increasing number of countries ratifying the Convention, JMSA established its Territorial Sea Baselines Research Office. Since then, it has been preparing the data to authenticate its territorial sea baselines. To do this it is analyzing and studying the selection methods for and appropriateness of the reference points for low-water lines, harbor structures, and the configurations of rocks and shorelines in the vicinity of low-water lines nationwide that could be used as reference points for territorial sea. It is using nautical charts and scientific documents, such as the "Basic Maps of the Sea in Coastal Waters," for this study.
In addition, since UNCLOS employs straight baselines as part of the territorial sea baselines, JMSA prepared data to authenticate territorial sea baselines when using straight baselines.
At present, JMSA is taking the steps to publicize nautical charts with straight baselines drawn based on the above efforts. In FY 1996, it will issue mainly small-scale nautical charts, which will indicate Japan's straight baselines.
(2) Oceanographic Surveys to Establish the Outer Limits of Continental Shelf, etc.
UNCLOS prescribes that a coastal State has possession of continental shelf that extend, as a rule, up until 200 nautical miles from its territorial sea baselines. If conditions meet UNCLOS specifications, a State may establish the outer limit of their continental shelf beyond 200 nautical miles from its territorial sea baselines. And if a State desires to do that, the Convention requires that the State submit to the "Commission on the Limits of the Continental Shelf," an organ UNCLOS establishes, scientific and technological data to substantiate the particulars regarding the outer limits in question. UNCLOS stipulates that this submission be made as quickly as possible, moreover, in any case, within ten years.
It is for this reason that, in 1983, JMSA established its Continental Shelf Surveys Office to obtain the basic data required to establish the outer limits of the continental shelf. This office uses large hydrographic survey vessels to conduct continental shelf surveys on submarine topography, geological structure, geomagnetism, gravity, and other related
