Ocean waters, scattering

Measurements by Thompson et al. (1978) on cultured populations of phytoplankton, such as might be expected to scatter light in ocean waters, revealed only a scattering matrix of the form (13.5), characteristic of particles for which either the Rayleigh (Chapter 5) or Rayleigh-Gans (Chapter 6) approximations are valid. 

Kadyshevich, Ye. A., Yu. S. Lyubovtseva, and G. V. Rozenberg, 1976. Light-scattering matrices of Pacific and Atlantic Ocean waters, Izv. Acad. Sci. USSR Atmos. Ocean. Phys., 12, 106-111. 

Xe data would be even more useful in this sense, if there were any. The best data are probably those of Mazor et al. (1964) (Table 4.6). Normalized as for Kr previously, their data yield AXe = +7% in surface water and AXe = -21% in deep water. The surface water result is similar to more recent AKr (Table 4.7). Although the Mazor et al. data also include approximately 20% saturation anomalies in Ne and Ar that would be considered spurious today, it is tempting to speculate that their deep water Xe undersaturation is real, possibly also the scattered but very low values of Bieri, Koide, and Goldberg (1964), since of all the noble gases Xe is the best candidate for an adsorptive sink in ocean water (cf. Chapter 2). 

Sirotyuk (ref. 25) found that the complete removal of solid particles from a sample of water increased the tensile strength by at most 30 percent, indicating that most of the gas nuclei present in high purity water are not associated with solid particles. Bernd (ref. 15,16) observed that gas phases stabilized in crevices are not usually truly stable, but instead tend to dissolve slowly. This instability is due to imperfections in the geometry of the liquid/gas interface, which is almost never exactly flat (ref. 114). Medwin (ref. 31,32) attributed the excess ultrasonic attenuation and backscatter measured in his ocean experiments to free microbubbles rather than to particulate bodies this distinction was based on the fact that marine microbubbles in resonance, but prior to ultrasonic cavitation (ref. 4), have acoustical scattering and absorption cross sections that are several orders of magnitude greater than those of particulate bodies (see Section 1.1.2). 

On time scales of oceanic circulation (1000 y and less) the internal distribution of carbonate system parameters is modified primarily by biological processes. Gross sections of the distribution of Aj and DIG in the world s oceans (Fig. 4.4) and scatter plots of the data for these quantities as a function of depth in the different ocean basins (Fig. 4.5) indicate that the concentrations increase in deep waters (1-4 Ion) from the North Atlantic to the Antarctic and into the Indian and Pacific Oceans following the conveyer belt circulation (Fig. 1.12). Degradation of organic matter (OM) and dissolution of GaGOs cause these increases in the deep waters. The chemical character of the particulate material that degrades and dissolves determines the ratio of At to DIG. 

These results obtained from a slick-covered water surface are of great importance for the interpretation of measured reductions of the radar back-scattering by oceanic surface films (see the preceding sections). However, we also note that results obtained from wind-wave tank experiments can-... 

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