Step-wise changes in glacier flow speed coincide with calving and glacial earthquakes at Helheim Glacier, Greenland

M. Nettles, T. B. Larsen, P. Elósegui, G.S. Hamilton, L.A. Stern, Andreas P. Ahlstrøm, J.L. Davis, M.L. Andersen, J. de Juan, Shfaqat Abbas Khan, Lars Stenseng, G. Ekström, René Forsberg

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

Geodetic observations show several large, sudden increases in flow speed at Helheim Glacier, one of Greenland's largest outlet glaciers, during summer, 2007. These step-like accelerations, detected along the length of the glacier, coincide with teleseismically detected glacial earthquakes and major iceberg calving events. No coseismic offset in the position of the glacier surface is observed; instead, modest tsunamis associated with the glacial earthquakes implicate glacier calving in the seismogenic process. Our results link changes in glacier velocity directly to calving-front behavior at Greenland's largest outlet glaciers, on timescales as short as minutes to hours, and clarify the mechanism by which glacial earthquakes occur. Citation: Nettles, M., et al. (2008), Step-wise changes in glacier flow speed coincide with calving and glacial earthquakes at Helheim Glacier, Greenland.
Original languageEnglish
JournalGeophysical Research Letters
Volume35
Issue number24
Pages (from-to)L24503
ISSN0094-8276
DOIs
Publication statusPublished - 2008

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