Is higher resolution bathymetry always better for undersea sound propagation modeling?

Abstract

Bathymetry is one of the most important environmental parameters affecting undersea sound transmission in shallow waters. There has always been a preference towards bathymetry with the highest resolution and accuracy when conducting sound propagation modeling. However, extreme care must be exercised in the selection of the correct bathymetric resolution. It will be demonstrated that the correct resolution depends on the source of the geoacoustic model used. Higher resolution bathymetries, such as multibeam surveys, introduce steeper slopes that yield larger bottom loss. If a lower resolution bathymetry was implemented to conduct geoacoustic inversion, then the same bathymetric resolution should be used to conduct subsequent sound transmission modeling. In addition, when geoacoustic inversion results are reported, the bathymetric resolution used must also be included.