Tidal bending of ice shelves as a mechanism for large-scale temporal variations in ice flow
| Autor: | G. Hilmar Gudmundsson, Sebastian Rosier |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2018 |
| Předmět: |
010504 meteorology & atmospheric sciences
Ice stream F800 Pressure ridge 010502 geochemistry & geophysics 01 natural sciences Ice shelf Physics::Geophysics Stamukha Physics::Atmospheric and Oceanic Physics lcsh:Environmental sciences 0105 earth and related environmental sciences Earth-Surface Processes Water Science and Technology Drift ice lcsh:GE1-350 geography geography.geographical_feature_category lcsh:QE1-996.5 Geophysics Current (stream) lcsh:Geology Fast ice Sea ice thickness Astrophysics::Earth and Planetary Astrophysics Geology |
| Zdroj: | The Cryosphere, Vol 12, Pp 1699-1713 (2018) |
| ISSN: | 1994-0424 1994-0416 |
| Popis: | GPS measurements reveal strong modulation of horizontal ice shelf and ice stream flow at a variety of tidal frequencies, most notably a fortnightly (Msf) frequency not present in the vertical tides themselves. Current theories largely fail to explain the strength and prevalence of this signal over floating ice shelves. We show how well-known non-linear aspects of ice rheology can give rise to widespread, long-periodic tidal modulation in ice shelf flow, generated within ice shelves themselves through tidal flexure acting at diurnal and semidiurnal frequencies. Using full-Stokes viscoelastic modelling, we show that inclusion of tidal bending within the model accounts for much of the observed tidal modulation of ice shelf flow. Furthermore, our model shows that, in the absence of vertical tidal forcing, the mean flow of the ice shelf is reduced by almost 30 % for the geometry that we consider. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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