Polarization of light in shallow waters

摘要

Measurements of the upwelling polarized radiance in relatively shallow waters of varying depths and benthic conditions are compared to simulationsrevealing the depolarizing nature of the seafloor. Significant correlations between simulations and measurements are attained when the appropriate unpolarized, Lambertian bottoms are included in the radiative transfer model. The bottoms used in this study produce realistic upwelling radiance distributions as well as ranges of the degree of linear polarization (DoLP) that peak between 10 and 30%. This study specifically finds that polarization in upwelling radiance is best preserved at long wavelengths in clear waters and also at short wavelengths in phytoplankton- and CDOM-rich waters. These results can thus facilitate the detection of benthic materials as well as future studies of camouflage by benthic biota.The DoLPwas found to be highly sensitive to benthic reflectance, but the angle of polarization (AoLP), which quantifies the orientation of polarization, is independent of it. The AoLP could therefore be used to communicate and sense direction underwater.