Recent ice dynamic and surface mass balance of Union Glacier in the West Antarctic Ice Sheet

Here we present the results of a comprehensive glaciological investigation of Union Glacier (79°46' S/83°24' W) in the West Antarctic Ice Sheet (WAIS), a major outlet glacier within the Ellsworth Mountains. Union Glacier flows into the Ronne Ice Shelf, where recent models have indicated th...

Full description

Bibliographic Details
Main Authors: A. Rivera, R. Zamora, J. A. Uribe, R. Jaña, J. Oberreuter
Format: Article
Language:English
Published: Copernicus Publications 2014-08-01
Series:The Cryosphere
Online Access:http://www.the-cryosphere.net/8/1445/2014/tc-8-1445-2014.pdf
_version_ 1818310947230449664
author A. Rivera
R. Zamora
J. A. Uribe
R. Jaña
J. Oberreuter
author_facet A. Rivera
R. Zamora
J. A. Uribe
R. Jaña
J. Oberreuter
author_sort A. Rivera
collection DOAJ
description Here we present the results of a comprehensive glaciological investigation of Union Glacier (79°46' S/83°24' W) in the West Antarctic Ice Sheet (WAIS), a major outlet glacier within the Ellsworth Mountains. Union Glacier flows into the Ronne Ice Shelf, where recent models have indicated the potential for significant grounding line zone (GLZ) migrations in response to changing climate and ocean conditions. To elaborate a glaciological base line that can help to evaluate the potential impact of this GLZ change scenario, we installed an array of stakes on Union Glacier in 2007. The stake network has been surveyed repeatedly for elevation, velocity, and net surface mass balance. The region of the stake measurements is in near-equilibrium, and ice speeds are 10 to 33 m a<sup>−1</sup>. Ground-penetrating radars (GPR) have been used to map the subglacial topography, internal structure, and crevasse frequency and depth along surveyed tracks in the stake site area. The bedrock in this area has a minimum elevation of −858 m a.s.l., significantly deeper than shown by BEDMAP2 data. However, between this deeper area and the local GLZ, there is a threshold where the subglacial topography shows a maximum altitude of 190 m. This subglacial condition implies that an upstream migration of the GLZ will not have strong effects on Union Glacier until it passes beyond this shallow ice pinning point.
first_indexed 2024-12-13T07:54:09Z
format Article
id doaj.art-5870645678d3443fb032f0b58e00f5ef
institution Directory Open Access Journal
issn 1994-0416
1994-0424
language English
last_indexed 2024-12-13T07:54:09Z
publishDate 2014-08-01
publisher Copernicus Publications
record_format Article
series The Cryosphere
spelling doaj.art-5870645678d3443fb032f0b58e00f5ef2022-12-21T23:54:35ZengCopernicus PublicationsThe Cryosphere1994-04161994-04242014-08-01841445145610.5194/tc-8-1445-2014Recent ice dynamic and surface mass balance of Union Glacier in the West Antarctic Ice SheetA. Rivera0R. Zamora1J. A. Uribe2R. Jaña3J. Oberreuter4Centro de Estudios Científicos, P.O. Box 5110466, Valdivia, ChileCentro de Estudios Científicos, P.O. Box 5110466, Valdivia, ChileCentro de Estudios Científicos, P.O. Box 5110466, Valdivia, ChileInstituto Antártico Chileno, Punta Arenas, ChileCentro de Estudios Científicos, P.O. Box 5110466, Valdivia, ChileHere we present the results of a comprehensive glaciological investigation of Union Glacier (79°46' S/83°24' W) in the West Antarctic Ice Sheet (WAIS), a major outlet glacier within the Ellsworth Mountains. Union Glacier flows into the Ronne Ice Shelf, where recent models have indicated the potential for significant grounding line zone (GLZ) migrations in response to changing climate and ocean conditions. To elaborate a glaciological base line that can help to evaluate the potential impact of this GLZ change scenario, we installed an array of stakes on Union Glacier in 2007. The stake network has been surveyed repeatedly for elevation, velocity, and net surface mass balance. The region of the stake measurements is in near-equilibrium, and ice speeds are 10 to 33 m a<sup>−1</sup>. Ground-penetrating radars (GPR) have been used to map the subglacial topography, internal structure, and crevasse frequency and depth along surveyed tracks in the stake site area. The bedrock in this area has a minimum elevation of −858 m a.s.l., significantly deeper than shown by BEDMAP2 data. However, between this deeper area and the local GLZ, there is a threshold where the subglacial topography shows a maximum altitude of 190 m. This subglacial condition implies that an upstream migration of the GLZ will not have strong effects on Union Glacier until it passes beyond this shallow ice pinning point.http://www.the-cryosphere.net/8/1445/2014/tc-8-1445-2014.pdf
spellingShingle A. Rivera
R. Zamora
J. A. Uribe
R. Jaña
J. Oberreuter
Recent ice dynamic and surface mass balance of Union Glacier in the West Antarctic Ice Sheet
The Cryosphere
title Recent ice dynamic and surface mass balance of Union Glacier in the West Antarctic Ice Sheet
title_full Recent ice dynamic and surface mass balance of Union Glacier in the West Antarctic Ice Sheet
title_fullStr Recent ice dynamic and surface mass balance of Union Glacier in the West Antarctic Ice Sheet
title_full_unstemmed Recent ice dynamic and surface mass balance of Union Glacier in the West Antarctic Ice Sheet
title_short Recent ice dynamic and surface mass balance of Union Glacier in the West Antarctic Ice Sheet
title_sort recent ice dynamic and surface mass balance of union glacier in the west antarctic ice sheet
url http://www.the-cryosphere.net/8/1445/2014/tc-8-1445-2014.pdf
work_keys_str_mv AT arivera recenticedynamicandsurfacemassbalanceofunionglacierinthewestantarcticicesheet
AT rzamora recenticedynamicandsurfacemassbalanceofunionglacierinthewestantarcticicesheet
AT jauribe recenticedynamicandsurfacemassbalanceofunionglacierinthewestantarcticicesheet
AT rjana recenticedynamicandsurfacemassbalanceofunionglacierinthewestantarcticicesheet
AT joberreuter recenticedynamicandsurfacemassbalanceofunionglacierinthewestantarcticicesheet