Seasonal variations in Greenland Ice Sheet motion: Inland extent and behaviour at higher elevations
We present global positioning system observations that capture the full inland extent of ice motion variations in 2009 along a transect in the west Greenland Ice sheet margin. In situ measurements of air temperature and surface ablation, and satellite monitoring of ice surface albedo and supraglacia...
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ftunivtasecite:oai:ecite.utas.edu.au:82154 2023-05-15T16:26:55+02:00 Seasonal variations in Greenland Ice Sheet motion: Inland extent and behaviour at higher elevations Bartholomew, ID Nienow, P Sole, A Mair, D Cowton, T King, MA Palmer, S 2011 https://doi.org/10.1016/j.epsl.2011.04.014 http://ecite.utas.edu.au/82154 en eng Elsevier Science Bv http://dx.doi.org/10.1016/j.epsl.2011.04.014 Bartholomew, ID and Nienow, P and Sole, A and Mair, D and Cowton, T and King, MA and Palmer, S, Seasonal variations in Greenland Ice Sheet motion: Inland extent and behaviour at higher elevations, Earth and Planetary Science Letters, 307, (3-4) pp. 271-278. ISSN 0012-821X (2011) [Refereed Article] http://ecite.utas.edu.au/82154 Earth Sciences Physical Geography and Environmental Geoscience Physical Geography and Environmental Geoscience not elsewhere classified Refereed Article PeerReviewed 2011 ftunivtasecite https://doi.org/10.1016/j.epsl.2011.04.014 2019-12-13T21:47:09Z We present global positioning system observations that capture the full inland extent of ice motion variations in 2009 along a transect in the west Greenland Ice sheet margin. In situ measurements of air temperature and surface ablation, and satellite monitoring of ice surface albedo and supraglacial lake drainage are used to investigate hydrological controls on ice velocity changes. We find a strong positive correlation between rates of annual ablation and changes in annual ice motion along the transect, with sites nearest the ice sheet margin experiencing greater annual variations in ice motion (15-18%) than those above 1000. m elevation (3-8%). Patterns in the timing and rate of meltwater delivery to the ice-bed interface provide key controls on the magnitude of hydrologically-forced velocity variations at each site. In the lower ablation zone, the overall contribution of variations in ice motion to annual flow rates is limited by evolution in the structure of the subglacial drainage system. At sites in the upper ablation zone, a shorter period of summer melting and delayed establishment of a hydraulic connection between the ice sheet surface and its bed limit the timeframe for velocity variations to occur. Our data suggest that land-terminating sections of the Greenland Ice Sheet will experience increased dynamic mass loss in a warmer climate, as the behaviour that we observe in the lower ablation zone propagates further inland. Findings from this study provide a conceptual framework to understand the impact of hydrologically-forced velocity variations on the future mass balance of land-terminating sections of the Greenland Ice Sheet. 2011 Elsevier B.V. Article in Journal/Newspaper Greenland Ice Sheet eCite UTAS (University of Tasmania) Greenland Earth and Planetary Science Letters 307 3-4 271 278 |
institution |
Open Polar |
collection |
eCite UTAS (University of Tasmania) |
op_collection_id |
ftunivtasecite |
language |
English |
topic |
Earth Sciences Physical Geography and Environmental Geoscience Physical Geography and Environmental Geoscience not elsewhere classified |
spellingShingle |
Earth Sciences Physical Geography and Environmental Geoscience Physical Geography and Environmental Geoscience not elsewhere classified Bartholomew, ID Nienow, P Sole, A Mair, D Cowton, T King, MA Palmer, S Seasonal variations in Greenland Ice Sheet motion: Inland extent and behaviour at higher elevations |
topic_facet |
Earth Sciences Physical Geography and Environmental Geoscience Physical Geography and Environmental Geoscience not elsewhere classified |
description |
We present global positioning system observations that capture the full inland extent of ice motion variations in 2009 along a transect in the west Greenland Ice sheet margin. In situ measurements of air temperature and surface ablation, and satellite monitoring of ice surface albedo and supraglacial lake drainage are used to investigate hydrological controls on ice velocity changes. We find a strong positive correlation between rates of annual ablation and changes in annual ice motion along the transect, with sites nearest the ice sheet margin experiencing greater annual variations in ice motion (15-18%) than those above 1000. m elevation (3-8%). Patterns in the timing and rate of meltwater delivery to the ice-bed interface provide key controls on the magnitude of hydrologically-forced velocity variations at each site. In the lower ablation zone, the overall contribution of variations in ice motion to annual flow rates is limited by evolution in the structure of the subglacial drainage system. At sites in the upper ablation zone, a shorter period of summer melting and delayed establishment of a hydraulic connection between the ice sheet surface and its bed limit the timeframe for velocity variations to occur. Our data suggest that land-terminating sections of the Greenland Ice Sheet will experience increased dynamic mass loss in a warmer climate, as the behaviour that we observe in the lower ablation zone propagates further inland. Findings from this study provide a conceptual framework to understand the impact of hydrologically-forced velocity variations on the future mass balance of land-terminating sections of the Greenland Ice Sheet. 2011 Elsevier B.V. |
format |
Article in Journal/Newspaper |
author |
Bartholomew, ID Nienow, P Sole, A Mair, D Cowton, T King, MA Palmer, S |
author_facet |
Bartholomew, ID Nienow, P Sole, A Mair, D Cowton, T King, MA Palmer, S |
author_sort |
Bartholomew, ID |
title |
Seasonal variations in Greenland Ice Sheet motion: Inland extent and behaviour at higher elevations |
title_short |
Seasonal variations in Greenland Ice Sheet motion: Inland extent and behaviour at higher elevations |
title_full |
Seasonal variations in Greenland Ice Sheet motion: Inland extent and behaviour at higher elevations |
title_fullStr |
Seasonal variations in Greenland Ice Sheet motion: Inland extent and behaviour at higher elevations |
title_full_unstemmed |
Seasonal variations in Greenland Ice Sheet motion: Inland extent and behaviour at higher elevations |
title_sort |
seasonal variations in greenland ice sheet motion: inland extent and behaviour at higher elevations |
publisher |
Elsevier Science Bv |
publishDate |
2011 |
url |
https://doi.org/10.1016/j.epsl.2011.04.014 http://ecite.utas.edu.au/82154 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland Ice Sheet |
genre_facet |
Greenland Ice Sheet |
op_relation |
http://dx.doi.org/10.1016/j.epsl.2011.04.014 Bartholomew, ID and Nienow, P and Sole, A and Mair, D and Cowton, T and King, MA and Palmer, S, Seasonal variations in Greenland Ice Sheet motion: Inland extent and behaviour at higher elevations, Earth and Planetary Science Letters, 307, (3-4) pp. 271-278. ISSN 0012-821X (2011) [Refereed Article] http://ecite.utas.edu.au/82154 |
op_doi |
https://doi.org/10.1016/j.epsl.2011.04.014 |
container_title |
Earth and Planetary Science Letters |
container_volume |
307 |
container_issue |
3-4 |
container_start_page |
271 |
op_container_end_page |
278 |
_version_ |
1766015941651464192 |