Which term refers to the low mean waterline along the coast?

The term that refers to the low mean waterline along the coast is "Baseline." The baseline serves as a reference point for measuring the breadth of the various maritime zones, such as territorial seas and contiguous zones. It is typically defined as the low-water line along the coast, as it marks the point where land meets the sea at low tide. This definition is foundational in international maritime law, as it establishes the starting point for determining the extent of a nation’s territorial waters and the rights associated with them.

The other options represent distinct maritime concepts. The U.S. Territorial Sea is the area up to 12 nautical miles from the baseline, where a state has sovereignty. The Contiguous Zone extends from the outer limit of the territorial sea to 24 nautical miles, allowing a state to enforce laws concerning customs, taxation, immigration, and pollution. Exclusive state waters typically refer to areas where a particular state has exclusive rights over resources, but these are based on broader regulations rather than the physical measurement defined by the baseline. Understanding the baseline is crucial for demarcating the various maritime zones and for navigation, law enforcement, and resource management.