Measurements of the magnitude and spectral distribution of the Raman-scattering coefficients of pure water (b_(rw)) and seawater (b_(rs)) are presented. Two independent measurements of the spectral distribution of the Raman-scattering coefficient of pure water were made for incident wavelengths ranging from 250 to 500 nm. These measurements revealed a strong dependence of b_(rw) on wavelength that could be represented by a (λ′)~(-5.3±0.3) relationship, where λ′ is the incident wavelength, or a λ~(-4.6±0.3) relationship, where λ is the Raman-scattered wavelength, when normalized to units of photons. The corresponding relationships for normalization to energy are (λ′)~(-5.5±0.4) and λ~(-4.8±0.3), respectively. These relationships are found to be consistent with resonance Raman theory for an absorption wavelength of 130 nm. The absolute value of b_(rw) for the 3400-cm~(-1) line was found to be (2.7 ± 0.2) × 10~(4) m~(-1) for an incident wavelength of 488 nm, which is consistent with a number of earlier reports. The difference between the magnitudes of the Raman-scattering coefficients for ware water and seawater was statistically insignificant.
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