community, there are several different meanings of reflectance: reflectivity, relative reflectance, pseudo-reflectance and absolute reflectance. Reflectivity is the
same as the intensity of laser energy return. Relative reflectance represents differences in reflectivity between pixels or clouds of pixels. Pseudo-reflectance and
absolute reflectance are derived using physics-based equations applied to full
waveform analysis or simple empirical estimation. Pseudo-reflectance can be
Fig. 7.4 Parameters extracted from SHOALS bathymetric LiDAR waveforms for Hilo Bay,
Hawaii: (a) SHOALS depth from 0–40 m, where lighter areas are deeper; (b) a ? b b , water
column absorption and backscattering, a measure of water clarity, where lighter areas are more
turbid; (c) water column volume reflectance, which is a ? b b integrated over the entire water
column, where lighter areas are more reflective; and (d) bottom reflectance, where lighter areas
are more reflective, in this case sand appears light and corals appear dark; and (e) water surface
reflectance, which is the sum of water column volume reflectance and bottom reflectance
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J. M. Wozencraft and J. Y. Park