CO 2
CO
COS
3.0 × 10
10
2.5 × 10
10
2.0 × 10
10
1.5 × 10
10
1.0 × 10
10
0.5 × 10
10
0
1.5 × 10
9
1.0 × 10
9
0.5 × 10
9
0
6 × 10
6
4 × 10
6
2 × 10
6
0
300
350
Wavelength (nm)
400
450
Y
(molecules cm
_
2
s
_
1
nm
_
1
)
Figure 5 Spectral dependence of the photochemical flux with depth for CO 2 , CO, and COS. Fluxes with depth are from the surface
to 0.25, 0.5, 1.0, 2.0, and 4 m, respectively (bottom spectrum to top spectrum). Below 4 m, increases in the flux are nominal. These
spectral dependencies were calculated using eqn [10], the wavelength dependence of the quantum yields for CO 2 , CO and COS
shown in Figure 3, and the surface solar irradiance shown in Figure 4A. CDOM is assumed to absorb all photons in this spectral
region (see Figures 1 and 4).
PHOTOCHEMICAL PROCESSES 97