Bed topography and subglacial landforms in the onset region of the Northeast Greenland Ice Stream
The Northeast Greenland Ice Stream (NEGIS) is an important dynamic component for the total mass balance of the Greenland ice sheet, as it reaches up to the central divide and drains 12% of the ice sheet. The geometric boundary conditions and in particular the nature of the subglacial bed of the NEGI...
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| Format: | Article |
| Language: | English |
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Cambridge University Press
2020-04-01
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| Series: | Annals of Glaciology |
| Subjects: | |
| Online Access: | https://www.cambridge.org/core/product/identifier/S0260305520000129/type/journal_article |
| _version_ | 1811157268946747392 |
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| author | Steven Franke Daniela Jansen Tobias Binder Nils Dörr Veit Helm John Paden Daniel Steinhage Olaf Eisen |
| author_facet | Steven Franke Daniela Jansen Tobias Binder Nils Dörr Veit Helm John Paden Daniel Steinhage Olaf Eisen |
| author_sort | Steven Franke |
| collection | DOAJ |
| description | The Northeast Greenland Ice Stream (NEGIS) is an important dynamic component for the total mass balance of the Greenland ice sheet, as it reaches up to the central divide and drains 12% of the ice sheet. The geometric boundary conditions and in particular the nature of the subglacial bed of the NEGIS are essential to understand its ice flow dynamics. We present a record of more than 8000 km of radar survey lines of multi-channel, ultra-wideband radio echo sounding data covering an area of 24 000 km2, centered on the drill site for the East Greenland Ice-core Project (EGRIP), in the upper part of the NEGIS catchment. Our data yield a new detailed model of ice-thickness distribution and basal topography in the region. The enhanced resolution of our bed topography model shows features which we interpret to be caused by erosional activity, potentially over several glacial–interglacial cycles. Off-nadir reflections from the ice–bed interface in the center of the ice stream indicate a streamlined bed with elongated subglacial landforms. Our new bed topography model will help to improve the basal boundary conditions of NEGIS prescribed for ice flow models and thus foster an improved understanding of the ice-dynamic setting. |
| first_indexed | 2024-04-10T05:04:26Z |
| format | Article |
| id | doaj.art-17011c89551442029bae6505cf93c3dd |
| institution | Directory Open Access Journal |
| issn | 0260-3055 1727-5644 |
| language | English |
| last_indexed | 2024-04-10T05:04:26Z |
| publishDate | 2020-04-01 |
| publisher | Cambridge University Press |
| record_format | Article |
| series | Annals of Glaciology |
| spelling | doaj.art-17011c89551442029bae6505cf93c3dd2023-03-09T12:27:39ZengCambridge University PressAnnals of Glaciology0260-30551727-56442020-04-016114315310.1017/aog.2020.12Bed topography and subglacial landforms in the onset region of the Northeast Greenland Ice StreamSteven Franke0https://orcid.org/0000-0001-8462-4379Daniela Jansen1https://orcid.org/0000-0002-4412-5820Tobias Binder2Nils Dörr3https://orcid.org/0000-0002-7594-7886Veit Helm4https://orcid.org/0000-0001-7788-9328John Paden5https://orcid.org/0000-0003-0775-6284Daniel Steinhage6https://orcid.org/0000-0003-4737-9751Olaf Eisen7https://orcid.org/0000-0002-6380-962XAlfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, GermanyAlfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, GermanyAlfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, GermanyAlfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, GermanyAlfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, GermanyCenter for Remote Sensing of Ice Sheets (CReSIS), University of Kansas, Lawrence, KS, USAAlfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, GermanyAlfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany Department of Geosciences, University of Bremen, Bremen, GermanyThe Northeast Greenland Ice Stream (NEGIS) is an important dynamic component for the total mass balance of the Greenland ice sheet, as it reaches up to the central divide and drains 12% of the ice sheet. The geometric boundary conditions and in particular the nature of the subglacial bed of the NEGIS are essential to understand its ice flow dynamics. We present a record of more than 8000 km of radar survey lines of multi-channel, ultra-wideband radio echo sounding data covering an area of 24 000 km2, centered on the drill site for the East Greenland Ice-core Project (EGRIP), in the upper part of the NEGIS catchment. Our data yield a new detailed model of ice-thickness distribution and basal topography in the region. The enhanced resolution of our bed topography model shows features which we interpret to be caused by erosional activity, potentially over several glacial–interglacial cycles. Off-nadir reflections from the ice–bed interface in the center of the ice stream indicate a streamlined bed with elongated subglacial landforms. Our new bed topography model will help to improve the basal boundary conditions of NEGIS prescribed for ice flow models and thus foster an improved understanding of the ice-dynamic setting.https://www.cambridge.org/core/product/identifier/S0260305520000129/type/journal_articleGlacial geomorphologyglacier flowice streamsprocesses and landforms of glacial erosionradio-echo sounding |
| spellingShingle | Steven Franke Daniela Jansen Tobias Binder Nils Dörr Veit Helm John Paden Daniel Steinhage Olaf Eisen Bed topography and subglacial landforms in the onset region of the Northeast Greenland Ice Stream Annals of Glaciology Glacial geomorphology glacier flow ice streams processes and landforms of glacial erosion radio-echo sounding |
| title | Bed topography and subglacial landforms in the onset region of the Northeast Greenland Ice Stream |
| title_full | Bed topography and subglacial landforms in the onset region of the Northeast Greenland Ice Stream |
| title_fullStr | Bed topography and subglacial landforms in the onset region of the Northeast Greenland Ice Stream |
| title_full_unstemmed | Bed topography and subglacial landforms in the onset region of the Northeast Greenland Ice Stream |
| title_short | Bed topography and subglacial landforms in the onset region of the Northeast Greenland Ice Stream |
| title_sort | bed topography and subglacial landforms in the onset region of the northeast greenland ice stream |
| topic | Glacial geomorphology glacier flow ice streams processes and landforms of glacial erosion radio-echo sounding |
| url | https://www.cambridge.org/core/product/identifier/S0260305520000129/type/journal_article |
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