Nuances of the Law of the Sea Implementation Affecting Ocean Research and Activities

South China Sea Joint Development Zones

South China is a highly contentious area of the world with regard to maritime claims and boundaries. Here, long straight baselines connecting offshore islands are very common (e.g., Vietnam, Thailand, Malaysia, and Indonesia). In this figure, in the southern South China Sea, one can see three joint development zones (JDZs)—Cambodia-Vietnam, Malaysia-Thailand, and Malaysia-Vietnam. With the number of overlapping claims in this sea and the desire to explore potential oil and gas resources near the Spratly Island group, it is likely additional JDZs will be negotiated in the future.

Similar JDZs exist for fishing or oil and gas beyond the South China Sea. Among them are ones for Colombia-Jamaica, Argentina-Uruguay, France-Italy, France-Spain, Bahrain-Saudi Arabia, and Kuwait-Saudi Arabia. Unresolved overlapping claims exist between Japan and Taiwan over Senkaku Island, between Japan and Russia over the Kuril Islands, elsewhere in the South China Sea, and between other nations in virtually every sea of the world.

Vietnamese Territorial Sea Limit

As an example of the effect of straight baseline claims on maritime area jurisdiction, this figure shows both the Vietnamese claimed territorial sea limit (stipple pattern) based on claimed straight baselines and a simple 12-nautical-mile buffer of the normal baseline, shown in brown on the graphic. Someone unfamiliar with straight baselines may mistakenly use the latter and would likely suffer costly consequences.

North Korea-Russia Maritime Boundary

North Korea’s east coast is an example of a long straight baseline resulting in much greater seaward limits as compared to the normal baseline. Consequently, an analyst or mariner could make an erroneous assumption about which countries claim a particular area and what types of jurisdiction they claim. The North Korea-Russia agreed maritime boundary shown in green presents an example of a simplified equidistant line, although it seems all the territorial concessions were in favor of Russia.

The General Dynamics-calculated equidistant line is shown in red. The North Korea-Russia agreed maritime boundary deviates from the equidistant line by as much as 10 nautical miles. The global maritime boundaries database uses boundary agreements instead of hypothetical equidistant lines when they exist.

Yugoslavian Maritime Boundary

In another case, Italy and the former Yugoslavia made jurisdictional tradeoffs and limited the effect of certain islands in determining their final maritime boundary. The agreed boundary coincided with the median line for only three-fifths of its length, and the two differed by as much as 12 nautical miles over the remainder.