Oceanic erosion of a floating Antarctic glacier in the Amundsen Sea
A survey of the southern Amundsen and Bellingshausen seas in early 1994 included the first deepoceanographic measurements along the calving front of Pine Island Glacier, which drains~2x10^5 km^2 of the marine-based West Antarctic Ice Sheet. The measurements reveal a cycloniccirculation in Pine Islan...
| Main Authors: | , , |
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| Format: | Article in Journal/Newspaper |
| Language: | unknown |
| Published: |
1998
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| Subjects: | |
| Online Access: | https://epic.awi.de/id/eprint/1254/ https://hdl.handle.net/10013/epic.11843 |
| Summary: | A survey of the southern Amundsen and Bellingshausen seas in early 1994 included the first deepoceanographic measurements along the calving front of Pine Island Glacier, which drains~2x10^5 km^2 of the marine-based West Antarctic Ice Sheet. The measurements reveal a cycloniccirculation in Pine Island Bay and >1 degC Circumpolar Deep Water flowing beneath and rapidlymelting the floating base of this deep-rooted glacier. Dissolved oxygen measurements show asubsurface oxygenation of the water column resulting from air bubbles in the melting ice. Seawateroxygen isotope analyses imply average delta18O values of -29 permil for precipitation on thecatchment basin that subsequently melts at the glacier base. Application of a two-dimensionalthermohaline circulation model to the sub-ice shelf cavity supports average basal melt rates inexcess of 10 m/a calculated by two other methods. This melt rate is more than 5 times the averagereported for any Antarctic ice shelf, drives Circumploar Deep Water upwelling on the continentalshelf, and generates melt-laden outflows that are well above surface freezing temperature. |
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