16.2 Mechanisms of Interactions of Solar Light with Absorbing
and Scattering Aquatic Media
Of all components constituting the radiant signal recorded by the remote sensor
overflying aquatic environments, it is only the radiance emerging from beneath the
water surface, L w ðþ0; lÞ carries the information on both the water quality and the
nature of sun photon interactions with the aquatic medium. However, being simultaneously the function of optical properties of water per se and the intensity and
Table 16.4 Spectral values of F for sun zenith angles 0
, 30
, 45
, 60
l, nm
F, relative units
y 0 ¼ 0
y 0 ¼ 30
y 0 ¼ 45
y 0 ¼ 60
410
0.32
0.38
0.42
0.55
430
0.30
0.35
0.38
0.50
450
0.27
0.33
0.35
0.46
470
0.25
0.31
0.32
0.42
490
0.23
0.29
0.30
0.39
510
0.21
0.28
0.28
0.37
530
0.20
0.26
0.26
0.35
550
0.19
0.25
0.25
0.33
570
0.18
0.23
0.24
0.32
590
0.17
0.22
0.23
0.31
610
0.17
0.21
0.22
0.29
630
0.16
0.20
0.21
0.28
650
0.15
0.20
0.20
0.27
670
0.14
0.19
0.19
0.26
690
0.14
0.18
0.18
0.25
Fig. 16.1 Simulated total
coefficient of water column
diffuse reflection, R tot (À0,l)
for the input data given in
Table 16.5
160
16 Quantification and Analysis of the Spectral Composition