An analysis of the tensor dielectric constant of sea ice at microwave frequencies

The bilocal approximation of strong fluctuation theory is used to develop a model for the tensor dielectric constant of sea ice that is treated as a random anisotropic medium. The application is a two-fold one: first the individual ice grains are treated as pure ice with embedded elongated brine cells with random spacings and sizes and secondly as the combined ice-brine system, which has tensor dielectric properties, with random orientations of the principal axes and random embedded air bubbles. Comparisons with measurements on a variety of ice types over the temperature range O to -32 degree C and frequencies from 0.1 to 40 GHz show that the theory is able to account quantitatively for large parts of the published data including expected scattering corrections to the quasi-static dielectric constant at low salinities and high frequencies.