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| Titel |
Present-day ice mass changes and glacial-isostatic adjustment in Antarctica from GRACE, ICESat / Envisat, GPS and viscoelastic modelling |
| VerfasserIn |
Ingo Sasgen, Martin Horwath, Nana Schoen, Elizabeth Petrie, Volker Klemann, Alexander Horvath, Roland Pail, Jonathan Bamber, Hannes Konrad, Peter Clarke, Mark Drinkwater |
| 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 |
250093155
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| Publikation (Nr.) |
 EGU/EGU2014-7633.pdf |
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| Zusammenfassung |
| Determining the mass balance of the Antarctic ice sheet from satellite gravimetry (GRACE),
and, to a lesser extent satellite altimetry (e.g. CryoSat), relies on corrections of the mass
transport in the Earth’s mantle and surface deformation related to the glacial isostatic
adjustment (GIA). Due to the scarcity of observational constraints on the ice sheet evolution,
as well as the lack of knowledge on the Earth’s rheological structure, GIA corrections remain
ambiguous. Therefore, signatures of GIA derived from contemporary space-geodetic
measurements are valuable new constraints. Here, we present our most recent advances of the
ESA-STSE Project REGINA (www.regina-science.eu) in estimating Antarctic GIA from
space-geodetic measurements; namely, gravity field trends recovered with GRACE,
GPS surface displacements, and ice sheet topographic change from ICESat/Envisat
satellite altimetry. We show that even though recent GIA predictions reconcile with
geodetic estimates at the continental scale, considerable regional deviations exist. A
prominent example is the Amundsen Sea Sector, where GPS data indicate GIA-induced
uplift of tens of mm/yr. Using forward modeling simulations, we show that, in
principle, this signature reconciles with recent mass loss and very low viscosity of
the Earth’s mantle. We conclude with estimating the impact of such small-scale
GIA signals on space-geodetic estimates of the regional Antarctic mass balance. |
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