Table 8.
Analytical approaches to identify bottom reflectance in shallow coastal
waters.
Author Technique
Assumptions
Seafloor Reflectance Estimations
Tassan (1996) Linear transformation algorithm.
The correlation of two wavelength bands
yields the ratio of the attenuation
coefficients.
Water column optical properties of deep water are similar
to the ones of the shallow water area.
Maritorena
et al. (1994)
Algorithm derived from the two-flow
equations and Monte Carlo simulations
Backscattering coefficient, and vertical diffuse
attenuation coefficient are not depth dependent.
Bottom is a lambertian reflector (completing absorbing).
Bottom contrast is exponentially attenuation in a two-way
light path.
Estep and Holloway
(1992)
Inverted single-scatter irradiance
Inputs for radiative transfer algorithm are provided from
Case 1 Jerlov tables
Spitzer and
Dirks (1987)
Two-flow radiative transfer
Waters are vertically well mixed
Coefficients are depth independent
Lyzenga (1978) Linear transformation algorithm.
The correlation of two wavelength bands
yields the ratio of the attenuation
coefficients.
Bottom reflected radiance is approximately a linear
function of the bottom reflectance and an exponential
function of the water depth.
Bathymetry Estimations
Philpot (1989) Single-scatter irradiance model. One scalar
variable is designed to respond linearly
with depth and a second to be sensitive only
to variations in bottom type.
Water quality and atmospheric conditions are stable within an image scene.
Clark et al.
(1987)
Application of a single-band reflectance
model and then dual-band ratio method.
Both are linear band methods.
Bottom reflectance is constant over the bottom type. Atmosphere, sea state, and other effects are uniform or constant.
Jain and Miller
(1977)
Two-flow approximation model
Water of uniform optical properties and thickness Pre-defined seafloor albedo
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Mapping and Management of Coral