Tide-modulated ice flow variations drive seismicity near the calving front of Bowdoin Glacier, Greenland

摘要: Glacier microseismicity is a promising tool to study glacier dynamics. However, physical processes connecting seismic signals and ice dynamics are not clearly understood at present. Particularly, the relationship between tide-modulated seismicity of calving glaciers remains elusive. Here we analyze records from an on-ice seismometer placed 250 m front Bowdoin Glacier, Greenland. Using high-frequency flow speed measurements, show that microseismic activity related strain rate variations. The correlates with longitudinal stretching measured surface. Both higher melt rates falling tides accelerate motion increase stretching. Long-term monitoring could therefore provide insights on how glacier's force balance regime react changes ice-ocean interface.