Passive Multispectral Bathymetry Mapping of Negril Shores, Jamaica

摘要

A new method was tested using SPOT images for mapping of variations of the reflectances and depth of sea-bottom French Polynesia, where the standard error on computed depth was less than 0.2 m for average depths of 2 m. The method uses"soils line" for zero-depth calibration and "brightest pixels line" for diffuse attenuation coefficients and actual value of K as linear functions of band rations, thus providing bottom depth and reflectances without field data. This method has been blind-tested using landsat TM data. TM should improve the possibilities ofampping deeper waters thanks to blue wavelength band. Preliminary results show very promising correlations with the echo-sounded sections along the Negril coast of Jamaica, where the bottom is a mixture of sand, corals and seagrass and 2K values of at 0.179, 0.251, 0.899 m-1 are estimated from the image at 486, 570 and 660 nm respectively. The outlines and performances of the PMBM process are presented, and the results of its application at Negril are presented and discussed.