Temporal englacial water content variability associated with a rapidly retreating glacier

This study uses a combination of evidence from ground penetrating radar, borehole, video, and wireless probe data to assess temporal changes in englacial water content associated with Briksdalsbreen, a rapidly retreating Norwegian glacier. Over a 13?day period in 2006, ice radar-wave velocity varied between 0·135?m/ns (±?0·009) and 0·159?m/ns (±?0·003), and water content from 7·8% (+2·6, ?2·8) to 2·5% (+0·9, ?1·1) [derived from the Looyenga (Physica31(3): 401–406, 1965) formula]. It is suggested that during warm precipitation free days, void spaces within the glacier become filled with water, resulting in low radar-wave velocity. This stored water then drained during cold, high precipitation days, allowing the radar-wave velocity to rise. These changes in englacial storage were caused by the enhanced crevassing generated by the newly floating ice margin, and were associated with accelerated glacier retreat