Radar Absorption, Basal Reflection, Thickness, and Polarization Measurements from the Ross Ice Shelf

• Main Authors: Barwick, S. W., Berg, E. C., Besson, D., Duffin, T., Hanson, J. C., Klein, S. R., Kleinfelder, S. A., Reed, C., Roumi, M., Stezelberger, T., Tatar, J., Walker, J., Zou, L.
• Format: Report
• Language: unknown
• Published: arXiv 2014
• Subjects: Instrumentation and Methods for Astrophysics astro-ph.IM; FOS Physical sciences; Ross Ice Shelf; Ice Shelf
• Online Access: https://dx.doi.org/10.48550/arxiv.1410.7134; https://arxiv.org/abs/1410.7134

Radio-glaciological parameters from Moore's Bay, in the Ross Ice Shelf, have been measured. The thickness of the ice shelf in Moore's Bay was measured from reflection times of radio-frequency pulses propagating vertically through the shelf and reflecting from the ocean, and is found to be $576\pm8$ m. Introducing a baseline of 543$\pm$7 m between radio transmitter and receiver allowed the computation of the basal reflection coefficient, $R$, separately from englacial loss. The depth-averaged attenuation length of the ice column, $$ is shown to depend linearly on frequency. The best fit (95% confidence level) is $= (460\pm20)-(180\pm40)ν$ m (20 dB/km), for the frequencies $ν=$[0.100-0.850] GHz, assuming no reflection loss. The mean electric-field reflection coefficient is $\sqrt{R}=0.82\pm0.07$ (-1.7 dB reflection loss) across [0.100-0.850] GHz, and is used to correct the attenuation length. Finally, the reflected power rotated into the orthogonal antenna polarization is less than 5% below 0.400 GHz, compatible with air propagation. The results imply that Moore's Bay serves as an appropriate medium for the ARIANNA high energy neutrino detector. : 10 pages, 6 figures