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| Titel |
A high-resolution bedrock map for the Antarctic Peninsula |
| VerfasserIn |
Matthias Huss, Daniel Farinotti |
| 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 |
250093542
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| Publikation (Nr.) |
 EGU/EGU2014-9505.pdf |
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| Zusammenfassung |
| Glaciers on the Antarctic Peninsula show a high sensitivity to changed climatic and
oceanic conditions and are expected to significantly contribute to sea-level rise over
the next decades. So far, the best bedrock data set for the region is the recently
released Bedmap2 providing ice thickness on a 1 km grid. Whereas for large-scale ice
sheet modelling the spatial resolution provided by Bedmap2 is sufficient, detailed
considerations of surface mass balance, ice flow and grounding line dynamics of
Antarctic Peninsula glaciers necessitate the application of models that are able
to cope with the high spatial variability of the governing processes. For ice flow
models used to predict future glacier response to climate change and/or ice shelf
break-off, a high-resolution bedrock topography is required as an essential boundary
condition.
Here, we derive a complete bedrock data set for the Antarctic Peninsula north of 70°S on
a 100 m grid. We further develop an established method to invert surface topography using
simple ice dynamic modelling to obtain distributed ice thickness. Our approach makes use of
a high-resolution digital elevation model, catchment boundaries for all glaciers of the
Peninsula, and RACMO-based surface mass balance data. The results are constrained with all
available thickness measurements from Operation IceBridge and gridded ice flow speeds for
the entire study region.
The new data set resolves the rugged subglacial topography in great detail, indicates
deeply incised troughs with thicknesses of up to 1500 m, and shows that 32% of the
ice volume is grounded below sea level. The Antarctic Peninsula has the potential
to raise global sea level by 71.9±5.8 mm. In comparison to Bedmap2 we find a
significantly higher mean ice thickness (+47%) which is attributed to the approach
used to calculate thickness in regions not covered with direct measurements. Our
high-resolution bedrock data set offers new possibilities for studying the contribution
of the Antarctic Peninsula to sea-level rise with state-of-the-art glacier models. |
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