Observing ice-shelf channels and basal melting from space
Ice-shelf channels (along-flow lineations in which ice is thinner) are ubiquitous in Antarctic ice shelves. Although these features are readily visible in satellite imagery, ice-thickness and ice-velocity variations in their surrounding are typically heavily undersampled. Ice-shelf channels focus ch...
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ftawi:oai:epic.awi.de:41451 2023-05-15T13:40:27+02:00 Observing ice-shelf channels and basal melting from space Berger, S. Drews, R. Helm, Veit Rack, W. Lenaerts, J. Ligtenberg, Stefan Pattyn, F. 2016-04 https://epic.awi.de/id/eprint/41451/ https://hdl.handle.net/10013/epic.48371 unknown Berger, S. , Drews, R. , Helm, V. orcid:0000-0001-7788-9328 , Rack, W. , Lenaerts, J. , Ligtenberg, S. and Pattyn, F. (2016) Observing ice-shelf channels and basal melting from space , EGU General Assembly 2016, Vienna, Austria, 17 April 2016 - 22 April 2016 . hdl:10013/epic.48371 EPIC3EGU General Assembly 2016, Vienna, Austria, 2016-04-17-2016-04-22 Conference notRev 2016 ftawi 2021-12-24T15:41:48Z Ice-shelf channels (along-flow lineations in which ice is thinner) are ubiquitous in Antarctic ice shelves. Although these features are readily visible in satellite imagery, ice-thickness and ice-velocity variations in their surrounding are typically heavily undersampled. Ice-shelf channels focus channelized melting and significantly alter the basal mass balance (and hence ice-shelf stability) on short horizontal scales. Here we use interferometrically-derived TandDEM-X digital elevation models and ice-flow velocities with a horizontal gridding of 125 m illustrating the ice-shelf dynamics of the Roi Baudouin Ice Shelf, Dronning Maud Land (East Antarctica) in unprecedented detail. Using ground-based GPS surface elevation, we demonstrate that TanDEM-X is an ideal sensor to map the channel morphology at the ice-shelf surface. We find velocity anomalies surrounding the channels along the entire ice shelf potentially indicating the presence of locally elevated basal melt rates. Using mass conservation in a Lagrangian framework, we find basal melt rates averaging 0.4 m/a in the middle of the ice shelf and peaking at 12 m/a inside some channels.We illustrate the sensitivity of the method with respect to systematic biases in elevation/velocity and also with respect to lateral variations of the depth-density relationship. With the increased availability of high-resolution radar satellites (such as Sentinel1), the techniques presented here could be applied on an pan-Antarctic scale to map basal melting both in space and time at high-resolution. Conference Object Antarc* Antarctic Antarctica Dronning Maud Land East Antarctica Ice Shelf Ice Shelves Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) Antarctic Dronning Maud Land East Antarctica Roi Baudouin ENVELOPE(24.461,24.461,-70.438,-70.438) |
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Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
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ftawi |
language |
unknown |
description |
Ice-shelf channels (along-flow lineations in which ice is thinner) are ubiquitous in Antarctic ice shelves. Although these features are readily visible in satellite imagery, ice-thickness and ice-velocity variations in their surrounding are typically heavily undersampled. Ice-shelf channels focus channelized melting and significantly alter the basal mass balance (and hence ice-shelf stability) on short horizontal scales. Here we use interferometrically-derived TandDEM-X digital elevation models and ice-flow velocities with a horizontal gridding of 125 m illustrating the ice-shelf dynamics of the Roi Baudouin Ice Shelf, Dronning Maud Land (East Antarctica) in unprecedented detail. Using ground-based GPS surface elevation, we demonstrate that TanDEM-X is an ideal sensor to map the channel morphology at the ice-shelf surface. We find velocity anomalies surrounding the channels along the entire ice shelf potentially indicating the presence of locally elevated basal melt rates. Using mass conservation in a Lagrangian framework, we find basal melt rates averaging 0.4 m/a in the middle of the ice shelf and peaking at 12 m/a inside some channels.We illustrate the sensitivity of the method with respect to systematic biases in elevation/velocity and also with respect to lateral variations of the depth-density relationship. With the increased availability of high-resolution radar satellites (such as Sentinel1), the techniques presented here could be applied on an pan-Antarctic scale to map basal melting both in space and time at high-resolution. |
format |
Conference Object |
author |
Berger, S. Drews, R. Helm, Veit Rack, W. Lenaerts, J. Ligtenberg, Stefan Pattyn, F. |
spellingShingle |
Berger, S. Drews, R. Helm, Veit Rack, W. Lenaerts, J. Ligtenberg, Stefan Pattyn, F. Observing ice-shelf channels and basal melting from space |
author_facet |
Berger, S. Drews, R. Helm, Veit Rack, W. Lenaerts, J. Ligtenberg, Stefan Pattyn, F. |
author_sort |
Berger, S. |
title |
Observing ice-shelf channels and basal melting from space |
title_short |
Observing ice-shelf channels and basal melting from space |
title_full |
Observing ice-shelf channels and basal melting from space |
title_fullStr |
Observing ice-shelf channels and basal melting from space |
title_full_unstemmed |
Observing ice-shelf channels and basal melting from space |
title_sort |
observing ice-shelf channels and basal melting from space |
publishDate |
2016 |
url |
https://epic.awi.de/id/eprint/41451/ https://hdl.handle.net/10013/epic.48371 |
long_lat |
ENVELOPE(24.461,24.461,-70.438,-70.438) |
geographic |
Antarctic Dronning Maud Land East Antarctica Roi Baudouin |
geographic_facet |
Antarctic Dronning Maud Land East Antarctica Roi Baudouin |
genre |
Antarc* Antarctic Antarctica Dronning Maud Land East Antarctica Ice Shelf Ice Shelves |
genre_facet |
Antarc* Antarctic Antarctica Dronning Maud Land East Antarctica Ice Shelf Ice Shelves |
op_source |
EPIC3EGU General Assembly 2016, Vienna, Austria, 2016-04-17-2016-04-22 |
op_relation |
Berger, S. , Drews, R. , Helm, V. orcid:0000-0001-7788-9328 , Rack, W. , Lenaerts, J. , Ligtenberg, S. and Pattyn, F. (2016) Observing ice-shelf channels and basal melting from space , EGU General Assembly 2016, Vienna, Austria, 17 April 2016 - 22 April 2016 . hdl:10013/epic.48371 |
_version_ |
1766135130680721408 |