## Abstract

There has been a large effort to relate the apparent
optical properties of ocean water to the inherent optical properties,
which are the absorption coefficient *a*, the scattering
coefficient *b*, and the scattering phase function
ρ(θ). The diffuse attenuation coefficient
*k*
_{diff} has most often been considered an apparent
optical property. However, *k*
_{diff} can be
considered a quasi-inherent property *k*
_{diff}′ when
defined as a steady-state light distribution attenuation
coefficient. The Honey–Wilson research empirically relates
*k*
_{diff} to *a* and *b*. The
Honey–Wilson relation most likely applies to a limited range of water
types because it does not include dependence on ρ(θ). A
series of Monte Carlo simulations were initiated to calculate
*k*
_{diff}′ in an unstratified water column. The
calculations, which reflected open ocean water types, used ranges of
the single-scattering albedo ω_{0} and the mean
forward-scattering angle θ_{m} for two analytic
phase functions with different shapes. It was found that
*k*
_{diff}′ is nearly independent of the shape of
ρ(θ) and can be easily parameterized in terms of *a*,
*b*, and θ_{m} for 0.11 ≤
θ_{m} ≤ 0.48 rad and 0.5 ≤
ω_{0} ≤ 0.95. *k*
_{diff}′ is an
asymptotic quantity; that is, a steady-state distribution is reached
only after many scattering lengths.

© 1999 Optical Society of America

Full Article | PDF Article