The United States witnessed a significant expansion of 386,000 square miles beneath the ocean surface last month, as per the latest findings from the US Department of State. The geographic coordinates defining the outer limits of America’s continental shelf have shifted beyond the 200 nautical miles mark from the coast.

This expansion, known as the extended continental shelf (ECS), primarily encompasses the shallow waters of the continental shelf. Notably, the US’s largest ECS area lies in the Arctic, stretching up to 350 nautical miles in the eastern section and over 680 nautical miles in the western portion, as revealed by the State Department on December 19.

The State Department emphasised that, in accordance with international law, the United States has the right to conserve and manage the abundant resources and crucial habitats present on and beneath its ECS. This underwater domain hosts various resources, including corals and crabs, serving as vital habitats for marine life. The US’s ECS spans six other regions: the Atlantic east coast, the Pacific west coast, the Bering Sea, the Mariana Islands, and two portions of the Gulf of Mexico, making it roughly double the size of California.

Experts at the Wilson Center, a Washington, DC-based think tank, pointed out that the ECS extension has significant implications for the US’s efforts to assert territorial rights in the Arctic region. The United States has long-standing economic interests in underwater territories rich in oil, natural gas, minerals, and sea life, and this extension reinforces its sovereign rights under the Law of the Sea Convention.

With the largest exclusive economic zone globally, the US can safeguard its sovereign rights to submerged areas. The Wilson Center sees this expansion as a crucial milestone, reflecting the nation’s commitment to the law of the sea, especially within the framework of the UN Convention on the Law of the Sea. Notably, the Wilson Center emphasised that there’s no necessity for future negotiations with Russia over territorial rights, citing a 1990 agreement that established continental shelf limits between the US and the Union of Soviet Socialist Republics.

The growth of the US’s ECS was meticulously measured by the State Department, employing analyses of depth, shape, and other submerged geophysical features. Data collection and analysis, spearheaded by the National Oceanic and Atmospheric Administration and the US Geological Survey since 2003, played a crucial role in unveiling this expansive development beneath the waves.