Attenuation of sound in glacier ice from 2 to 35 kHz

Abstract

The acoustic damping of sound waves in natural glaciers is a largely unexplored physical property that has relevance for various applications. We present measurements of the attenuation of sound in ice with a dedicated measurement setup in situ on the Italian glacier Langenferner from August 2017. The tested frequency ranges from 2 kHz to 35 kHz and probed distances between 5 m and 90 m. The attenuation length has been determined by two different methods including detailed investigations of systematic uncertainties. The attenuation length decreases with increasing frequencies. Observed values range between 13 m for low frequencies and 5 m for high frequencies. The presented results improve in accuracy with respect to previous measurements. However, the observed attenuation is found to be remarkably similar to observations at very different locations.