Law of the Sea
71% of the globe is covered by water - and increasing. (For UK projections click here). Thus there is tension between Nation States as to who has jurisdiction over particular areas of the sea.
The defining instrument of international law is UNCLOS III, which entered in to force in 1994. For those countries who have signed up see
Issues which UNCLOS attempts to deal with: Pollution, Navigation, Archipelagic Status, Transit Regimes, EEZ's, Continental Shelfs, Jurisdiction, Mining/Extraction, Research and Dispute Setlement. To this should be added the so-called War Against Terror. The United States of America is particularly concerned that the WAT is undermined by UNCLOS.
There are various terms applicable to UNCLOS that need to be defined. for a graphic...
Baseline: Lowest Astronomical Tide; note that the baseline can be straightened up pin the event of a heavily indented coastline.
Internal Waters: Waters inside of baseline. There is no right of innocent passage for foreign flag ships.
Territorial Waters: 12 NM from the baseline. Foreign flag ships have right of passage. The coastal state has full jurisdiction.
Contiguous Zone: A further 12 NM can be declared (ie 24 NM from Baseline) to give jurisdiction over issues such as UCH (underwater coastal heritage, smuggling and immigration.
EEZ: Exclusive Economic Zone
For a full report on CZM in the Irish Sea and Bristol Channel, see . This is an excellent paper from DEFRA indicating areas of debate over the management of the coastal zone.