Sudden increase in tidal response linked to calving and acceleration at a large Greenland outlet glacier

Julia de Juan, Pedro Elósegui, Meredith Nettles, Tine B. Larsen, James L. Davis, Gordon S. Hamilton, Leigh A. Stearns, Morten L. Andersen, Göran Ekström, Andreas P. Ahlstrøm, Lars Stenseng, S. Abbas Khan, René Forsberg

Publikation: Bidrag til tidsskriftArtikelForskningpeer review

41 Citationer (Scopus)

Resumé

Large calving events at Greenlands largest outlet glaciers are associated with glacial earthquakes and nearinstantaneous increases in glacier flow speed. At some glaciers and ice streams, flow is also modulated in a regular way by ocean tidal forcing at the terminus. At Helheim Glacier, analysis of geodetic data shows decimeter-level periodic position variations in response to tidal forcing. However, we also observe transient increases of more than 100% in the glaciers responsiveness to such tidal forcing following glacial-earthquake calving events. The timing and amplitude of the changes correlate strongly with the step-like increases in glacier speed and longitudinal strain rate associated with glacial earthquakes. The enhanced response to the ocean tides may be explained by a temporary disruption of the subglacial drainage system and a concomitant reduction of the friction at the ice-bedrock interface, and suggests a new means by which geodetic data may be used to infer glacier properties.

OriginalsprogEngelsk
ArtikelnummerL12501
Antal sider5
TidsskriftGeophysical Research Letters
Vol/bind37
Udgave nummer12
DOI
StatusUdgivet - jun. 2010

Programområde

  • Programområde 5: Natur og klima

Fingeraftryk

Dyk ned i forskningsemnerne om 'Sudden increase in tidal response linked to calving and acceleration at a large Greenland outlet glacier'. Sammen danner de et unikt fingeraftryk.

Citationsformater