Subglacial controls on dynamic thinning at Trinity-Wykeham Glacier, Prince of Wales Ice Field, Canadian Arctic
Mass loss from glaciers and ice caps represents the largest terrestrial component of current sea level rise. However, our understanding of how the processes governing mass loss will respond to climate warming remains incomplete. This study explores the relationship between surface elevation changes...
Published in: | International Journal of Remote Sensing |
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Main Authors: | , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
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2020
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Online Access: | https://risweb.st-andrews.ac.uk/portal/en/researchoutput/subglacial-controls-on-dynamic-thinning-at-trinitywykeham-glacier-prince-of-wales-ice-field-canadian-arctic(56830730-6386-4800-9e90-6292c3aab1d3).html https://doi.org/10.1080/01431161.2019.1658238 |
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ftunstandrewcris:oai:risweb.st-andrews.ac.uk:publications/56830730-6386-4800-9e90-6292c3aab1d3 2023-05-15T14:26:38+02:00 Subglacial controls on dynamic thinning at Trinity-Wykeham Glacier, Prince of Wales Ice Field, Canadian Arctic Harcourt, William D. Palmer, Steven J. Mansell, Damien T. Le Brocq, Anne Bartlett, Oliver Gourmelen, Noel Tepes, Paul Dowdeswell, Julian A. Blankenship, Donald D. Young, Duncan A. 2020 https://risweb.st-andrews.ac.uk/portal/en/researchoutput/subglacial-controls-on-dynamic-thinning-at-trinitywykeham-glacier-prince-of-wales-ice-field-canadian-arctic(56830730-6386-4800-9e90-6292c3aab1d3).html https://doi.org/10.1080/01431161.2019.1658238 eng eng info:eu-repo/semantics/restrictedAccess Harcourt , W D , Palmer , S J , Mansell , D T , Le Brocq , A , Bartlett , O , Gourmelen , N , Tepes , P , Dowdeswell , J A , Blankenship , D D & Young , D A 2020 , ' Subglacial controls on dynamic thinning at Trinity-Wykeham Glacier, Prince of Wales Ice Field, Canadian Arctic ' , International Journal of Remote Sensing , vol. 41 , no. 3 , pp. 1191-1213 . https://doi.org/10.1080/01431161.2019.1658238 Mass-loss Greenland Caps Amplification Archiplelago Discharge Altimetry Islands Nunavut article 2020 ftunstandrewcris https://doi.org/10.1080/01431161.2019.1658238 2022-06-02T07:51:59Z Mass loss from glaciers and ice caps represents the largest terrestrial component of current sea level rise. However, our understanding of how the processes governing mass loss will respond to climate warming remains incomplete. This study explores the relationship between surface elevation changes (d h /d t ), glacier velocity changes (d u /d t ), and bedrock topography at the Trinity-Wykeham Glacier system (TWG), Canadian High Arctic, using a range of satellite and airborne datasets. We use measurements of dh/dt from ICESat (2003-2009) and CryoSat-2 (2010-2016) repeat observations to show that rates of surface lowering increased from 4 m yr -1 to 6 m yr -1 across the lowermost 10 km of the TWG. We show that surface flow rates at both Trinity Glacier and Wykeham Glacier doubled over 16 years, during which time the ice front retreated 4.45 km. The combination of thinning, acceleration and retreat of the TWG suggests that a dynamic thinning mechanism is responsible for the observed changes, and we suggest that both glaciers have transitioned from fully grounded to partially floating. Furthermore, by comparing the separate glacier troughs we suggest that the dynamic changes are modulated by both lateral friction from the valley sides and the complex geometry of the bed. Further, the presence of bedrock ridges induces crevassing on the surface and provides a direct link for surface meltwater to reach the bed. We observe supraglacial lakes that drain at the end of summer and are concurrent with a reduction in glacier velocity, suggesting hydrological connections between the surface and the bed significantly impact ice flow. The bedrock topography thus has a primary influence on the nature of the changes in ice dynamics observed over the last decade. Article in Journal/Newspaper Arctic Arctic glacier Greenland Nunavut University of St Andrews: Research Portal Arctic Greenland Nunavut Trinity Glacier ENVELOPE(-78.553,-78.553,77.966,77.966) Wykeham Glacier ENVELOPE(-78.702,-78.702,77.907,77.907) International Journal of Remote Sensing 41 3 1191 1213 |
institution |
Open Polar |
collection |
University of St Andrews: Research Portal |
op_collection_id |
ftunstandrewcris |
language |
English |
topic |
Mass-loss Greenland Caps Amplification Archiplelago Discharge Altimetry Islands Nunavut |
spellingShingle |
Mass-loss Greenland Caps Amplification Archiplelago Discharge Altimetry Islands Nunavut Harcourt, William D. Palmer, Steven J. Mansell, Damien T. Le Brocq, Anne Bartlett, Oliver Gourmelen, Noel Tepes, Paul Dowdeswell, Julian A. Blankenship, Donald D. Young, Duncan A. Subglacial controls on dynamic thinning at Trinity-Wykeham Glacier, Prince of Wales Ice Field, Canadian Arctic |
topic_facet |
Mass-loss Greenland Caps Amplification Archiplelago Discharge Altimetry Islands Nunavut |
description |
Mass loss from glaciers and ice caps represents the largest terrestrial component of current sea level rise. However, our understanding of how the processes governing mass loss will respond to climate warming remains incomplete. This study explores the relationship between surface elevation changes (d h /d t ), glacier velocity changes (d u /d t ), and bedrock topography at the Trinity-Wykeham Glacier system (TWG), Canadian High Arctic, using a range of satellite and airborne datasets. We use measurements of dh/dt from ICESat (2003-2009) and CryoSat-2 (2010-2016) repeat observations to show that rates of surface lowering increased from 4 m yr -1 to 6 m yr -1 across the lowermost 10 km of the TWG. We show that surface flow rates at both Trinity Glacier and Wykeham Glacier doubled over 16 years, during which time the ice front retreated 4.45 km. The combination of thinning, acceleration and retreat of the TWG suggests that a dynamic thinning mechanism is responsible for the observed changes, and we suggest that both glaciers have transitioned from fully grounded to partially floating. Furthermore, by comparing the separate glacier troughs we suggest that the dynamic changes are modulated by both lateral friction from the valley sides and the complex geometry of the bed. Further, the presence of bedrock ridges induces crevassing on the surface and provides a direct link for surface meltwater to reach the bed. We observe supraglacial lakes that drain at the end of summer and are concurrent with a reduction in glacier velocity, suggesting hydrological connections between the surface and the bed significantly impact ice flow. The bedrock topography thus has a primary influence on the nature of the changes in ice dynamics observed over the last decade. |
format |
Article in Journal/Newspaper |
author |
Harcourt, William D. Palmer, Steven J. Mansell, Damien T. Le Brocq, Anne Bartlett, Oliver Gourmelen, Noel Tepes, Paul Dowdeswell, Julian A. Blankenship, Donald D. Young, Duncan A. |
author_facet |
Harcourt, William D. Palmer, Steven J. Mansell, Damien T. Le Brocq, Anne Bartlett, Oliver Gourmelen, Noel Tepes, Paul Dowdeswell, Julian A. Blankenship, Donald D. Young, Duncan A. |
author_sort |
Harcourt, William D. |
title |
Subglacial controls on dynamic thinning at Trinity-Wykeham Glacier, Prince of Wales Ice Field, Canadian Arctic |
title_short |
Subglacial controls on dynamic thinning at Trinity-Wykeham Glacier, Prince of Wales Ice Field, Canadian Arctic |
title_full |
Subglacial controls on dynamic thinning at Trinity-Wykeham Glacier, Prince of Wales Ice Field, Canadian Arctic |
title_fullStr |
Subglacial controls on dynamic thinning at Trinity-Wykeham Glacier, Prince of Wales Ice Field, Canadian Arctic |
title_full_unstemmed |
Subglacial controls on dynamic thinning at Trinity-Wykeham Glacier, Prince of Wales Ice Field, Canadian Arctic |
title_sort |
subglacial controls on dynamic thinning at trinity-wykeham glacier, prince of wales ice field, canadian arctic |
publishDate |
2020 |
url |
https://risweb.st-andrews.ac.uk/portal/en/researchoutput/subglacial-controls-on-dynamic-thinning-at-trinitywykeham-glacier-prince-of-wales-ice-field-canadian-arctic(56830730-6386-4800-9e90-6292c3aab1d3).html https://doi.org/10.1080/01431161.2019.1658238 |
long_lat |
ENVELOPE(-78.553,-78.553,77.966,77.966) ENVELOPE(-78.702,-78.702,77.907,77.907) |
geographic |
Arctic Greenland Nunavut Trinity Glacier Wykeham Glacier |
geographic_facet |
Arctic Greenland Nunavut Trinity Glacier Wykeham Glacier |
genre |
Arctic Arctic glacier Greenland Nunavut |
genre_facet |
Arctic Arctic glacier Greenland Nunavut |
op_source |
Harcourt , W D , Palmer , S J , Mansell , D T , Le Brocq , A , Bartlett , O , Gourmelen , N , Tepes , P , Dowdeswell , J A , Blankenship , D D & Young , D A 2020 , ' Subglacial controls on dynamic thinning at Trinity-Wykeham Glacier, Prince of Wales Ice Field, Canadian Arctic ' , International Journal of Remote Sensing , vol. 41 , no. 3 , pp. 1191-1213 . https://doi.org/10.1080/01431161.2019.1658238 |
op_rights |
info:eu-repo/semantics/restrictedAccess |
op_doi |
https://doi.org/10.1080/01431161.2019.1658238 |
container_title |
International Journal of Remote Sensing |
container_volume |
41 |
container_issue |
3 |
container_start_page |
1191 |
op_container_end_page |
1213 |
_version_ |
1766299910713376768 |