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

S. W. Barwick; E. C. Berg; D. Besson; T. Duffin; J. C. Hanson; S. R. Klein; S. A. Kleinfelder; C. Reed; M. Roumi; T. Stezelberger; J. Tatar; J. Walker; L. Zou

arXiv · 1410.7134

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

S. W. Barwick·E. C. Berg·D. Besson·T. Duffin·J. C. Hanson·S. R. Klein·S. A. Kleinfelder·C. Reed·M. Roumi·T. Stezelberger·J. Tatar·J. Walker·L. Zou

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Abstract

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)\nu$ m (20 dB/km), for the frequencies $\nu=$[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.

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S. W. Barwick, E. C. Berg, D. Besson, T. Duffin, J. C. Hanson, S. R. Klein, S. A. Kleinfelder, C. Reed, M. Roumi, T. Stezelberger, J. Tatar, J. Walker, L. Zou. 2014-10-27. Radar Absorption, Basal Reflection, Thickness, and Polarization Measurements from the Ross Ice Shelf. https://arxiv.org/abs/1410.7134

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