Analysis of CLCS Recommendations in light of their relevance to the delineation of a United States Extended Continental Shelf (ECS) in the Arctic

Onni B. Irish, University of New Hampshire, Durham


Article 76 of the United Nations Convention on the Law of the Sea provides a mechanism by which a coastal State can extend sovereign rights over the seafloor and subsurface outside of its 200 nautical mile exclusive economic zone. In order for a coastal State to delineate this region, often referred to as the extended continental shelf (ECS), bathymetric, geophysical and geological data must be collected and analyzed to define the limit of the juridical continental shelf defined within Article 76. The coastal State must present its ECS delineation to the Commission on the Limits of the Continental Shelf (CLCS). The CLCS reviews coastal States’ submissions and issues recommendations concerning the proposed ECS boundary and its accordance with Article 76. The United States has a potential ECS in the Chukchi Borderland region north of Alaska. This thesis examined two coastal States’ CLCS recommendations in regions morphologically similar to the Chukchi Borderland, the Kerguelen Plateau (Australia) and Vøring margin (Norway), to assess the criteria that the CLCS utilized to classify these features in order to forecast the impact these recommendations may have on a potential submission of the United States in the Chukchi Borderland region. This thesis has found that the CLCS requires a coastal State with seafloor highs that are connected to its continental margin to show that these features are (or are not) morphologically and geologically continuous with the continental margin and landmass. If the coastal State can prove the seafloor high under question satisfies both of these criteria, it could potentially increase the coastal State’s final ECS outer boundary. Application of these criteria to the Chukchi Borderland region found that available data could substantiate an argument that the Chukchi Borderland fulfills both criteria; however, further geological data may need to be collected from the northern extension of the Chukchi Borderland to support an Article 76 seafloor high classification.