Global Ocean Analysis Offers Cost-Effective Alternative for Seafloor Positioning

A recent study highlights the potential of global ocean analysis products to replace costly in-situ sound speed measurements for precise seafloor positioning, offering a significant reduction in expenses and logistical hurdles. Published in Satellite Navigation, the research demonstrates that the HYbrid Coordinate Ocean Model (HYCOM) global ocean analysis achieves centimeter-level accuracy, comparable to traditional methods, without the need for expensive sound speed field surveys.

The Global Navigation Satellite System-Acoustic (GNSS-A) technique, essential for studying tectonic movements and marine resource exploration, traditionally relies on in-situ sound speed profiles (SSPs). These measurements are not only costly but also challenging to collect due to variations in ocean conditions. The study's findings suggest that HYCOM global ocean analysis derived SSPs provide a viable alternative, with horizontal positioning accuracy of 0.2 cm (RMS) and vertical accuracy of 2.9 cm (RMS), closely matching traditional in-situ measurements.

Dr. Yanxiong Liu, the study's corresponding author, emphasized the practicality of global ocean analysis sound speed profiles as a cost-effective alternative that could broaden access to seafloor geodetic technology. This innovation is particularly promising for earthquake-prone regions and offshore industries, offering a more affordable option for high-precision seafloor positioning and monitoring.

The study's implications extend to unmanned vehicle navigation and deep-sea exploration, potentially advancing our understanding of seafloor science by making marine geodesy more accessible. For more details, the study is available at https://doi.org/10.1186/s43020-025-00170-z.