An isotropic model is used to describe and estimate the % polarization in a horizontal direction in the ocean at near-asymptotic depth. It is found that when the radiance distribution is described by a fourth power ellipse the % polarization = ε2, where ε is the eccentricity of the ellipse.
Tyler, J. E.. 1963. "Estimation of per cent polarization in deep oceanic water." Journal of Marine Research 21, (2). https://elischolar.library.yale.edu/journal_of_marine_research/998