Dielectric properties of brine-wetted snow on first-year sea ice

摘要

We present measurements, empirical models and a semi-physical dielectric mixture model for the dielectric constant and dielectric loss of brine-wetted snow on first-year sea ice. Experimental data include snow temperatures from -15.9° to 0.0 ℃ and snow salinities from 0.1 to 12 parts/thousand. We compare dielectric measurements at 50 MHz with brine volume fraction, brine saturation and snow temperature. We present a dielectric mixture model for brine-wetted snow, with depolarization factors and conductivity parameters fitted to experimental data. The dielectric constant of snow increases by a factor of 78.65 times the brine volume fraction. The dielectric loss and conductivity also increase with brine volume fraction. We provide a theoretical treatment of the frequency dispersion of brine-wetted snow between 10 MHz and 40 GHz. The dielectric properties of brine-wetted snow are highly sensitive to changes in brine volume fraction and snow temperature.