Backscattering from sea ice with vertical structural variation: a model analysis

Based on the matrix doubling method, a sea ice scattering model which accounts for the effects of vertical structural variation is developed. The sea ice layer is modeled as many sublayers with different physical characteristic determined by the vertical structural variation profile. Each sublayer is assumed to be statistically homogeneous. In addition to the effects of vertical structural variation, the developed sea ice scattering model also accounts for the effects of scatterer close spacing and rough top and bottom layer boundaries. Model verification has been carried out using measurements from well characterized sea ice. Preliminary model analyses are carried out for saline and desalinated ice. In the saline ice case, better salinity profile sensitivity is observed at 5 GHz than at 10 GHz. On the desalinated ice case where the scatterers are air bubbles, the sublayer with larger scatterers dominates the back scattering level even though its thickness is less than 1/10 of the signal penetration depth