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| Titel |
Dynamics of grounding zones under tidal forcing |
| VerfasserIn |
Roiy Sayag, Grae Worster |
| Konferenz |
EGU General Assembly 2014
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 16 (2014) |
| Datensatznummer |
250094046
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| Publikation (Nr.) |
 EGU/EGU2014-9357.pdf |
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| Zusammenfassung |
| We combine the dynamics of ice, bed and ocean in a new elastic model
for the tidal-timescale migration of grounding lines on deformable
foundations. Previous interpretations of tidal flexure using models of
elastic ice shelves with fixed grounding lines were found to be
inconsistent, suggesting an elasticity of ice that varies spatially
and temporally and that is significantly smaller than measured
experimentally. We argue that, with our model, a consistent, purely
elastic interpretation can be made. Combining this new approach with
remote-sensing measurements, we show that the grounding line migrates
several kilometers during a tidal cycle, that we can infer the
effective elastic properties of the bed, and that the elastic pressure
of the ice leads to a hydrological barrier near the grounding line and
controls subglacial hydrology. Our findings imply that subglacial
lubrication and melting induced by the ocean thermal forcing can
increase substantially during high tide. Consequently, these processes
can combine to accelerate the mass transfer from ice sheets to the
ocean, and contribute to sea level rise. |
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