Vertical Extension of the Subglacial Drainage System into Basal Crevasses
Water plays a first-order role in basal sliding of glaciers and ice sheets and is often a key constituent of accelerated glacier motion1, 2, 3, 4. Subglacial water is known to occupy systems of cavities and conduits at the interface between ice and the underlying bed surface, depending upon the hist...
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ftboisestateu:oai:scholarworks.boisestate.edu:cgiss_facpubs-1065 2023-10-29T02:36:28+01:00 Vertical Extension of the Subglacial Drainage System into Basal Crevasses Harper, Joel T. Bradford, John H. Humphrey, Neil F. Meierbachtol, Toby W. 2010-09-30T07:00:00Z https://scholarworks.boisestate.edu/cgiss_facpubs/65 https://doi.org/10.1038/nature09398 unknown ScholarWorks https://scholarworks.boisestate.edu/cgiss_facpubs/65 http://dx.doi.org/10.1038/nature09398 CGISS Publications and Presentations geophysics climate science geology Geosciences Earth Sciences Geophysics and Seismology text 2010 ftboisestateu https://doi.org/10.1038/nature09398 2023-09-29T15:03:46Z Water plays a first-order role in basal sliding of glaciers and ice sheets and is often a key constituent of accelerated glacier motion1, 2, 3, 4. Subglacial water is known to occupy systems of cavities and conduits at the interface between ice and the underlying bed surface, depending upon the history of water input and the characteristics of the substrate5. Full understanding of the extent and configuration of basal water is lacking, however, because direct observation is difficult. This limits our ability to simulate ice dynamics and the subsequent impacts on sea-level rise realistically. Here we show that the subglacial hydrological system can have a large volume of water occupying basal crevasses that extend upward from the bed into the overlying ice. Radar and seismic imaging combined with in situ borehole measurements collected on Bench Glacier, Alaska, reveal numerous water-filled basal crevasses with highly transmissive connections to the bed. Some crevasses extend many tens of metres above the bed and together they hold a volume of water equivalent to at least a decimetre layer covering the bed. Our results demonstrate that the basal hydrologic system can extend high into the overlying ice mass, where basal crevasses increase water-storage capacity and could potentially modulate basal water pressure. Because basal crevasses can form under commonly observed glaciological conditions, our findings have implications for interpreting and modelling subglacial hydrologic processes and related sliding accelerations of glaciers and ice sheets. Text glacier glaciers Alaska Boise State University: Scholar Works Nature 467 7315 579 582 |
institution |
Open Polar |
collection |
Boise State University: Scholar Works |
op_collection_id |
ftboisestateu |
language |
unknown |
topic |
geophysics climate science geology Geosciences Earth Sciences Geophysics and Seismology |
spellingShingle |
geophysics climate science geology Geosciences Earth Sciences Geophysics and Seismology Harper, Joel T. Bradford, John H. Humphrey, Neil F. Meierbachtol, Toby W. Vertical Extension of the Subglacial Drainage System into Basal Crevasses |
topic_facet |
geophysics climate science geology Geosciences Earth Sciences Geophysics and Seismology |
description |
Water plays a first-order role in basal sliding of glaciers and ice sheets and is often a key constituent of accelerated glacier motion1, 2, 3, 4. Subglacial water is known to occupy systems of cavities and conduits at the interface between ice and the underlying bed surface, depending upon the history of water input and the characteristics of the substrate5. Full understanding of the extent and configuration of basal water is lacking, however, because direct observation is difficult. This limits our ability to simulate ice dynamics and the subsequent impacts on sea-level rise realistically. Here we show that the subglacial hydrological system can have a large volume of water occupying basal crevasses that extend upward from the bed into the overlying ice. Radar and seismic imaging combined with in situ borehole measurements collected on Bench Glacier, Alaska, reveal numerous water-filled basal crevasses with highly transmissive connections to the bed. Some crevasses extend many tens of metres above the bed and together they hold a volume of water equivalent to at least a decimetre layer covering the bed. Our results demonstrate that the basal hydrologic system can extend high into the overlying ice mass, where basal crevasses increase water-storage capacity and could potentially modulate basal water pressure. Because basal crevasses can form under commonly observed glaciological conditions, our findings have implications for interpreting and modelling subglacial hydrologic processes and related sliding accelerations of glaciers and ice sheets. |
format |
Text |
author |
Harper, Joel T. Bradford, John H. Humphrey, Neil F. Meierbachtol, Toby W. |
author_facet |
Harper, Joel T. Bradford, John H. Humphrey, Neil F. Meierbachtol, Toby W. |
author_sort |
Harper, Joel T. |
title |
Vertical Extension of the Subglacial Drainage System into Basal Crevasses |
title_short |
Vertical Extension of the Subglacial Drainage System into Basal Crevasses |
title_full |
Vertical Extension of the Subglacial Drainage System into Basal Crevasses |
title_fullStr |
Vertical Extension of the Subglacial Drainage System into Basal Crevasses |
title_full_unstemmed |
Vertical Extension of the Subglacial Drainage System into Basal Crevasses |
title_sort |
vertical extension of the subglacial drainage system into basal crevasses |
publisher |
ScholarWorks |
publishDate |
2010 |
url |
https://scholarworks.boisestate.edu/cgiss_facpubs/65 https://doi.org/10.1038/nature09398 |
genre |
glacier glaciers Alaska |
genre_facet |
glacier glaciers Alaska |
op_source |
CGISS Publications and Presentations |
op_relation |
https://scholarworks.boisestate.edu/cgiss_facpubs/65 http://dx.doi.org/10.1038/nature09398 |
op_doi |
https://doi.org/10.1038/nature09398 |
container_title |
Nature |
container_volume |
467 |
container_issue |
7315 |
container_start_page |
579 |
op_container_end_page |
582 |
_version_ |
1781060423163838464 |