Derivation and Integration of Shallow-Water Bathymetry: Implications for Coastal Terrain Modeling and Subsequent Analyses

Abstract

Satellite and acoustic remote sensing enable the collection of high-resolution seafloor bathymetry data for integration with terrestrial elevations into coastal terrain models. A model of Tutuila Island, American Samoa, is created using depths derived from IKONOS satellite imagery to provide data in the near-shore gap between sea level and the beginning of sonar data at 10–15 m depth. A derivation method gauging the relative attenuation of blue and green spectral radiation is proven the most effective of several proposed in recent literature. The resulting coastal terrain model is shown to be accurate through statistical analyses and topographic profiles.

Keywords:

• Coastal terrain model
• satellite remote sensing
• IKONOS
• seafloor/seabed mapping
• marine geomorphology
• image processing
• coral reefs and islands
• American Samoa

Acknowledgements

Sincere thanks to NOAA's Pacific Islands Benthic Habitat Mapping Center for providing the multibeam sonar bathymetry. Thanks also to NOAA's Pacific Island Fisheries Science Center, Coral Reef Ecosystem Division, whose oceanography team collected field control points during a busy deployment schedule on the 2008 American Samoa Research and Management Program research cruise aboard the NOAA R/V Hi'ialakai. These data proved essential to product analysis. Additional thanks to the Biogeography Group of NOAA's Center for Coastal Monitoring and Assessment and NOAA's Coastal Services Center for providing the at-sensor IKONOS imagery needed for deriving bathymetry. Finally, the reviews of two anonymous referees improved the manuscript.