Mosaic of gridded multibeam bathymetry and bathymetry derived from multispectral IKONOS satellite imagery of Tau Island, Territory of American Samoa, USA
Description
Gridded multibeam bathymetry is integrated with bathymetry derived from multispectral IKONOS satellite data. Gridded (10 m cell size) multibeam bathymetry collected aboard NOAA Ship Hiialaka'i and R/V AHI. Bathymetry values shallower than 15 m were derived by gauging the reletive attenuation of blue and green spectral radiance as a function of depth. A multiple linear regression analysis of linearized blue and green spectral values against depth determined the variables of y-intercept, blue slope and green slope values. Variables then used in multivariate slope intercept formula to derive depth. Variables were adjusted to improve the statistical accuracy of the final derived bathymetry product. Digital image processing to derive depths conducted with the ENVI 4.3 software program while data editing and integration was performed using ArcGIS 9.3. This data set is for the shelf environment of Tau Island, American Samoa.