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

被引：41

作者：

de Juan, Julia ^{[1
]}

Elosegui, Pedro ^{[1
]}

Nettles, Meredith ^{[2
]}

Larsen, Tine B. ^{[3
]}

Davis, James L. ^{[4
]}

Hamilton, Gordon S. ^{[5
]}

Stearns, Leigh A. ^{[6
]}

Andersen, Morten L. ^{[3
,7
]}

Ekstroem, Goeran ^{[2
]}

Ahlstrom, Andreas P. ^{[3
]}

Stenseng, Lars ^{[8
]}

Khan, S. Abbas ^{[8
]}

Forsberg, Rene ^{[8
]}

机构：

[1] CSIC IEEC, Inst Space Sci, E-08034 Barcelona, Spain

[2] Columbia Univ, Lamont Doherty Earth Observ, Palisades, NY 10964 USA

[3] Geol Survey Denmark & Greenland, DK-1350 Copenhagen, Denmark

[4] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA

[5] Univ Maine, Climate Change Inst, Orono, ME 04469 USA

[6] Univ Kansas, Dept Geol, Lawrence, KS 66045 USA

[7] Univ Copenhagen, Niels Bohr Inst, Ctr Ice & Climate, DK-2100 Copenhagen, Denmark

[8] Natl Space Inst, DTU Space, DK-2100 Copenhagen, Denmark

来源：

GEOPHYSICAL RESEARCH LETTERS | 2010年 / 37卷

基金：

美国国家科学基金会;

关键词：

ANTARCTIC ICE STREAM; WEST ANTARCTICA; VELOCITY; SHEET; ISBRAE; SPEED;

D O I：

10.1029/2010GL043289

中图分类号：

P [天文学、地球科学];

学科分类号：

07 ;

摘要：

Large calving events at Greenland's largest outlet glaciers are associated with glacial earthquakes and near instantaneous 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 glacier's 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. Citation: de Juan, J., et al. (2010), Sudden increase in tidal response linked to calving and acceleration at a large Greenland outlet glacier, Geophys. Res. Lett., 37, L12501, doi: 10.1029/2010GL043289.

引用

页数：5

共 32 条

[1] Glacier, fjord, and seismic response to recent large calving events, Jakobshavn Isbrae, Greenland [J].