Inversion of IceBridge gravity data for continental shelf bathymetry beneath the Larsen Ice Shelf, Antarctica
A possible cause for accelerated thinning and break-up of floating marine ice shelves is warming of the water in the cavity below the ice shelf. Accurate bathymetry beneath large ice shelves is crucial for developing models of the ocean circulation in the sub-ice cavities. A grid of free-air gravity...
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ftdatacite:10.7916/d8-7hn3-9685 2023-05-15T13:37:36+02:00 Inversion of IceBridge gravity data for continental shelf bathymetry beneath the Larsen Ice Shelf, Antarctica Cochran, James R. Bell, Robin E. 2012 https://dx.doi.org/10.7916/d8-7hn3-9685 https://academiccommons.columbia.edu/doi/10.7916/d8-7hn3-9685 unknown Columbia University https://dx.doi.org/10.3189/2012jog11j033 Geophysics FOS Earth and related environmental sciences Ice shelves Continental shelf Gravity--Data processing Bathymetric maps Text Articles article-journal ScholarlyArticle 2012 ftdatacite https://doi.org/10.7916/d8-7hn3-9685 https://doi.org/10.3189/2012jog11j033 2021-11-05T12:55:41Z A possible cause for accelerated thinning and break-up of floating marine ice shelves is warming of the water in the cavity below the ice shelf. Accurate bathymetry beneath large ice shelves is crucial for developing models of the ocean circulation in the sub-ice cavities. A grid of free-air gravity data over the floating Larsen C ice shelf collected during the IceBridge 2009 Antarctic campaign was utilized to develop the first bathymetry model of the underlying continental shelf. Independent control on the continental shelf geologic structures from marine surveys was used to constrain the inversion. Depths on the continental shelf beneath the ice shelf estimated from the inversion generally range from about 350 to 650 m, but vary from < 300 to > 1000 m. Localized overdeepenings, 20–30 km long and 900–1000 m deep, are located in inlets just seaward of the grounding line. Submarine valleys extending seaward from the overdeepenings coalesce into two broad troughs that extend to the seaward limit of the ice shelf and appear to extend to the edge of the continental shelf. The troughs are generally at a depth of 550–700 m although the southernmost mapped trough deepens to over 1000 m near the edge of the ice shelf just south of 68°S. The combination of the newly determined bathymetry with published ice-draft determinations based on laser altimetry and radar data defines the geometry of the water-filled cavity. These newly imaged troughs provide a conduit for water to traverse the continental shelf and interact with the overlying Larsen C ice shelf and the grounding lines of the outlet glaciers. Text Antarc* Antarctic Antarctica Ice Shelf Ice Shelves Larsen Ice Shelf DataCite Metadata Store (German National Library of Science and Technology) Antarctic Larsen Ice Shelf ENVELOPE(-62.500,-62.500,-67.500,-67.500) |
institution |
Open Polar |
collection |
DataCite Metadata Store (German National Library of Science and Technology) |
op_collection_id |
ftdatacite |
language |
unknown |
topic |
Geophysics FOS Earth and related environmental sciences Ice shelves Continental shelf Gravity--Data processing Bathymetric maps |
spellingShingle |
Geophysics FOS Earth and related environmental sciences Ice shelves Continental shelf Gravity--Data processing Bathymetric maps Cochran, James R. Bell, Robin E. Inversion of IceBridge gravity data for continental shelf bathymetry beneath the Larsen Ice Shelf, Antarctica |
topic_facet |
Geophysics FOS Earth and related environmental sciences Ice shelves Continental shelf Gravity--Data processing Bathymetric maps |
description |
A possible cause for accelerated thinning and break-up of floating marine ice shelves is warming of the water in the cavity below the ice shelf. Accurate bathymetry beneath large ice shelves is crucial for developing models of the ocean circulation in the sub-ice cavities. A grid of free-air gravity data over the floating Larsen C ice shelf collected during the IceBridge 2009 Antarctic campaign was utilized to develop the first bathymetry model of the underlying continental shelf. Independent control on the continental shelf geologic structures from marine surveys was used to constrain the inversion. Depths on the continental shelf beneath the ice shelf estimated from the inversion generally range from about 350 to 650 m, but vary from < 300 to > 1000 m. Localized overdeepenings, 20–30 km long and 900–1000 m deep, are located in inlets just seaward of the grounding line. Submarine valleys extending seaward from the overdeepenings coalesce into two broad troughs that extend to the seaward limit of the ice shelf and appear to extend to the edge of the continental shelf. The troughs are generally at a depth of 550–700 m although the southernmost mapped trough deepens to over 1000 m near the edge of the ice shelf just south of 68°S. The combination of the newly determined bathymetry with published ice-draft determinations based on laser altimetry and radar data defines the geometry of the water-filled cavity. These newly imaged troughs provide a conduit for water to traverse the continental shelf and interact with the overlying Larsen C ice shelf and the grounding lines of the outlet glaciers. |
format |
Text |
author |
Cochran, James R. Bell, Robin E. |
author_facet |
Cochran, James R. Bell, Robin E. |
author_sort |
Cochran, James R. |
title |
Inversion of IceBridge gravity data for continental shelf bathymetry beneath the Larsen Ice Shelf, Antarctica |
title_short |
Inversion of IceBridge gravity data for continental shelf bathymetry beneath the Larsen Ice Shelf, Antarctica |
title_full |
Inversion of IceBridge gravity data for continental shelf bathymetry beneath the Larsen Ice Shelf, Antarctica |
title_fullStr |
Inversion of IceBridge gravity data for continental shelf bathymetry beneath the Larsen Ice Shelf, Antarctica |
title_full_unstemmed |
Inversion of IceBridge gravity data for continental shelf bathymetry beneath the Larsen Ice Shelf, Antarctica |
title_sort |
inversion of icebridge gravity data for continental shelf bathymetry beneath the larsen ice shelf, antarctica |
publisher |
Columbia University |
publishDate |
2012 |
url |
https://dx.doi.org/10.7916/d8-7hn3-9685 https://academiccommons.columbia.edu/doi/10.7916/d8-7hn3-9685 |
long_lat |
ENVELOPE(-62.500,-62.500,-67.500,-67.500) |
geographic |
Antarctic Larsen Ice Shelf |
geographic_facet |
Antarctic Larsen Ice Shelf |
genre |
Antarc* Antarctic Antarctica Ice Shelf Ice Shelves Larsen Ice Shelf |
genre_facet |
Antarc* Antarctic Antarctica Ice Shelf Ice Shelves Larsen Ice Shelf |
op_relation |
https://dx.doi.org/10.3189/2012jog11j033 |
op_doi |
https://doi.org/10.7916/d8-7hn3-9685 https://doi.org/10.3189/2012jog11j033 |
_version_ |
1766094629350932480 |