China Expands Seabed Mapping for Submarine Enhancement

China has launched an expansive program to map the seabeds and monitor ocean conditions across the Pacific, Indian, and Arctic oceans, deploying dozens of research vessels and hundreds of underwater sensors in strategic waters. Naval experts assess that the effort, publicly described as scientific research on climate and topography, generates data essential for enhancing submarine navigation and detection capabilities in potential conflicts with the United States and its allies.

The initiative involves systematic surveys by state-linked vessels, including the Dong Fang Hong 3 from Ocean University of China. Between 2024 and 2025, this ship conducted operations near Taiwan, Guam, and the Indian Ocean, including checks on ocean sensors off Japan's coast in October 2024 and a return visit in May 2025. It also mapped approaches to the Malacca Strait, a vital global trade chokepoint between Indonesia and Sri Lanka, in March 2025. Analysis of over five years of ship-tracking data reveals at least 42 vessels following precise, grid-like patterns in militarily sensitive areas such as those around the Philippines, Hawaii, Wake Atoll, and east of Japan. These locations align with key...