A recent study has unveiled that global ocean analysis products can serve as a viable alternative to costly in-situ sound speed measurements for achieving precise seafloor positioning. Published in Satellite Navigation on June 30, 2025, the research highlights the use of the HYbrid Coordinate Ocean Model (HYCOM) global ocean analysis to attain centimeter-level accuracy in seafloor positioning, mirroring the results of traditional methods but at a fraction of the cost.
The Global Navigation Satellite System-Acoustic (GNSS-A) technique, essential for studying tectonic movements and marine resource exploration, traditionally depends on expensive in-situ sound speed profiles (SSPs). The study demonstrates that HYCOM global ocean analysis derived SSPs offer horizontal positioning accuracy of 0.2 cm (RMS) and vertical accuracy of 2.9 cm (RMS), closely matching the precision of in-situ measurements without the associated high costs and logistical hurdles.
Dr. Yanxiong Liu, the study's corresponding author, emphasized the practicality of global ocean analysis sound speed profiles as a cost-effective alternative, potentially broadening access to seafloor geodetic technology for scientific and industrial applications. This advancement could significantly benefit earthquake-prone regions and offshore industries by facilitating more affordable and frequent high-precision surveys.
The study's implications extend to unmanned vehicle navigation and deep-sea exploration, offering a promising avenue for advancing marine geodesy and enhancing our understanding of seafloor science. For more details, the study is available at https://doi.org/10.1186/s43020-025-00170-z.
