An asymptotic closure theory for irradiance in the sea and its inversion to obtain the inherent optical properties

• Published in: Limnology and Oceanography
• Main Author: Zaneveld, J. Ronald V.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1989
• Subjects: North Atlantic
• Online Access: http://dx.doi.org/10.4319/lo.1989.34.8.1442; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.4319%2Flo.1989.34.8.1442; https://onlinelibrary.wiley.com/doi/pdf/10.4319/lo.1989.34.8.1442; https://aslopubs.onlinelibrary.wiley.com/doi/pdf/10.4319/lo.1989.34.8.1442

An expression is derived for the rate at which the diffuse attenuation coefficient for vector irradiance approaches its asymptotic value in a homogeneous medium. The asymptotic approach rate is shown to be a function of boundary conditions at the surface and the asymptotic diffuse attenuation coefficient which is an inherent optical property. The asymptotic approach rate is then used to derive the vertical structure of the vector and scalar irradiances, the vector and scalar diffuse attenuation coefficients, the average cosine of the light field, and the remotely sensed reflectance at the surface, based only on the surface values of the vector and scalar irradiances and the vector and scalar diffuse attenuation coefficients. This theory is inverted and combined with previously derived radiative transfer relations to show that in principle the vertical structure of the absorption, scattering, attenuation, and backscattering coefficients can be derived from the vertical structure of the scalar and vector irradiances and the nadir radiance. An example for the western North Atlantic Ocean is provided.