Seismic attenuation in glacial ice: A proxy for englacial temperature

[1] Seismic attenuation α, or internal friction Q−1, in glacial ice is highly sensitive to temperature, particularly near the melting point. Here we detail a technique to estimate Q and apply it to active source seismic data from Jakobshavn Isbrae, Greenland. We compare our results to measured and modeled temperature profiles of the ice in the region. We find an excellent match, with differences between seismically estimated and modeled temperatures of less than 2°C. Mapping variations in seismic Q through glacial ice thus is shown to allow detailed estimation of englacial temperature profiles, which may be of special value in regions where in situ measurements are logistically difficult.

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