A Theoretical Model of Radiative Transfer in Young Sea Ice

A four stream discrete-ordinates photometric model including both anisotropic scattering and refraction at the boundaries is presented which treats the case of a floating ice slab. The effects of refraction and reflection on the redistribution of the incident radiation field as it enters the ice are examined in detail. Using one- and two-layer models, theoretical albedos and transmittances are compared to values measured in the laboratory for thin salt ice. With an experimentally determined three-parameter Henyey–Greenstein phase function, comparisons at 650 nm yield single-scattering albedos ranging from 0.95 to 0.9997. The models are then used to compare the effects of diffuse and direct-beam incident radiation, to investigate the dependence of spectral albedo and transmittance on ice thickness, and to determine the influence of very cold and melted surface layers.