Quantifying bed roughness beneath contemporary and palaeo-ice streams
ABSTRACT Bed roughness is an important control on ice-stream location and dynamics. The majority of previous bed roughness studies have been based on data derived from radio-echo sounding (RES) transects across Antarctica and Greenland. However, the wide spacing of RES transects means that the links...
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crcambridgeupr:10.1017/jog.2018.71 2024-03-03T08:38:22+00:00 Quantifying bed roughness beneath contemporary and palaeo-ice streams FALCINI, FRANCESCA A.M. RIPPIN, DAVID M. KRABBENDAM, MAARTEN SELBY, KATHERINE A. 2018 http://dx.doi.org/10.1017/jog.2018.71 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143018000710 en eng Cambridge University Press (CUP) http://creativecommons.org/licenses/by/4.0/ Journal of Glaciology volume 64, issue 247, page 822-834 ISSN 0022-1430 1727-5652 Earth-Surface Processes journal-article 2018 crcambridgeupr https://doi.org/10.1017/jog.2018.71 2024-02-08T08:49:29Z ABSTRACT Bed roughness is an important control on ice-stream location and dynamics. The majority of previous bed roughness studies have been based on data derived from radio-echo sounding (RES) transects across Antarctica and Greenland. However, the wide spacing of RES transects means that the links between roughness and flow are poorly constrained. Here, we use Digital Terrain Model/bathymetry data from a well-preserved palaeo-ice stream to investigate basal controls on the behaviour of contemporary ice streams. Artificial transects were set up across the Minch Palaeo-Ice Stream (NW Scotland) to mimic RES flight lines over Institute and Möller Ice Streams (Antarctica). We then explored how different data-resolution, transect orientation and spacing, and different methods, impact roughness measurements. Our results show that fast palaeo-ice flow can occur over a rough, hard bed, not just a smooth, soft bed, as previous work has suggested. Smooth areas of the bed occur over both bedrock and sediment covered regions. Similar trends in bed roughness values were found using Fast Fourier Transform analysis and standard deviation methods. Smoothing of bed roughness results can hide important details. We propose that the typical spacing of RES transects is too wide to capture different landform assemblages and that transect orientation influences bed roughness measurements in both contemporary and palaeo-ice-stream setting. Article in Journal/Newspaper Antarc* Antarctica Greenland Journal of Glaciology Cambridge University Press Greenland Journal of Glaciology 64 247 822 834 |
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Open Polar |
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Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
topic |
Earth-Surface Processes |
spellingShingle |
Earth-Surface Processes FALCINI, FRANCESCA A.M. RIPPIN, DAVID M. KRABBENDAM, MAARTEN SELBY, KATHERINE A. Quantifying bed roughness beneath contemporary and palaeo-ice streams |
topic_facet |
Earth-Surface Processes |
description |
ABSTRACT Bed roughness is an important control on ice-stream location and dynamics. The majority of previous bed roughness studies have been based on data derived from radio-echo sounding (RES) transects across Antarctica and Greenland. However, the wide spacing of RES transects means that the links between roughness and flow are poorly constrained. Here, we use Digital Terrain Model/bathymetry data from a well-preserved palaeo-ice stream to investigate basal controls on the behaviour of contemporary ice streams. Artificial transects were set up across the Minch Palaeo-Ice Stream (NW Scotland) to mimic RES flight lines over Institute and Möller Ice Streams (Antarctica). We then explored how different data-resolution, transect orientation and spacing, and different methods, impact roughness measurements. Our results show that fast palaeo-ice flow can occur over a rough, hard bed, not just a smooth, soft bed, as previous work has suggested. Smooth areas of the bed occur over both bedrock and sediment covered regions. Similar trends in bed roughness values were found using Fast Fourier Transform analysis and standard deviation methods. Smoothing of bed roughness results can hide important details. We propose that the typical spacing of RES transects is too wide to capture different landform assemblages and that transect orientation influences bed roughness measurements in both contemporary and palaeo-ice-stream setting. |
format |
Article in Journal/Newspaper |
author |
FALCINI, FRANCESCA A.M. RIPPIN, DAVID M. KRABBENDAM, MAARTEN SELBY, KATHERINE A. |
author_facet |
FALCINI, FRANCESCA A.M. RIPPIN, DAVID M. KRABBENDAM, MAARTEN SELBY, KATHERINE A. |
author_sort |
FALCINI, FRANCESCA A.M. |
title |
Quantifying bed roughness beneath contemporary and palaeo-ice streams |
title_short |
Quantifying bed roughness beneath contemporary and palaeo-ice streams |
title_full |
Quantifying bed roughness beneath contemporary and palaeo-ice streams |
title_fullStr |
Quantifying bed roughness beneath contemporary and palaeo-ice streams |
title_full_unstemmed |
Quantifying bed roughness beneath contemporary and palaeo-ice streams |
title_sort |
quantifying bed roughness beneath contemporary and palaeo-ice streams |
publisher |
Cambridge University Press (CUP) |
publishDate |
2018 |
url |
http://dx.doi.org/10.1017/jog.2018.71 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143018000710 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Antarc* Antarctica Greenland Journal of Glaciology |
genre_facet |
Antarc* Antarctica Greenland Journal of Glaciology |
op_source |
Journal of Glaciology volume 64, issue 247, page 822-834 ISSN 0022-1430 1727-5652 |
op_rights |
http://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.1017/jog.2018.71 |
container_title |
Journal of Glaciology |
container_volume |
64 |
container_issue |
247 |
container_start_page |
822 |
op_container_end_page |
834 |
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1792506748299378688 |