Changing contribution of peak velocity events to annual velocities following a multi-decadal slowdown at White Glacier
ABSTRACT As the focus of intensive glaciological studies in the 1960–70s, White Glacier on Axel Heiberg Island, Canada, has played an important role in understanding the dynamics of mostly-cold polythermal glaciers in the high Arctic. In this study, we examine the magnitude, duration and timing of p...
Published in: | Annals of Glaciology |
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Language: | English |
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Online Access: | http://dx.doi.org/10.1017/aog.2017.46 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0260305517000465 |
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crcambridgeupr:10.1017/aog.2017.46 2024-06-09T07:38:29+00:00 Changing contribution of peak velocity events to annual velocities following a multi-decadal slowdown at White Glacier Thomson, Laura I. Copland, Luke 2017 http://dx.doi.org/10.1017/aog.2017.46 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0260305517000465 en eng Cambridge University Press (CUP) http://creativecommons.org/licenses/by/4.0/ Annals of Glaciology volume 58, issue 75pt2, page 145-154 ISSN 0260-3055 1727-5644 journal-article 2017 crcambridgeupr https://doi.org/10.1017/aog.2017.46 2024-05-15T13:07:38Z ABSTRACT As the focus of intensive glaciological studies in the 1960–70s, White Glacier on Axel Heiberg Island, Canada, has played an important role in understanding the dynamics of mostly-cold polythermal glaciers in the high Arctic. In this study, we examine the magnitude, duration and timing of peak velocity events in the summers of 2013–15 using continuous dual-frequency GPS observations, and compare them with similar measurements made in 1968. Summer speed-up events in 1968 and 2014, in which ice velocities reached 200% above winter values, were found to occur in conjunction with formation and drainage of an ice-marginal lake. Despite thinning of the glacier by >20 m and a decrease in annual surface velocities of 15–35% since the 1960s, the relative magnitude and duration of these peak events has increased, particularly at lower elevations, in comparison with the observations at the same locations many decades ago. Given the long-term slowdown of the glacier, the relative contribution of summer displacement to the net annual motion has therefore increased significantly, with summer motion over the span of <2 months now accounting for nearly half of the total annual displacement. Article in Journal/Newspaper Annals of Glaciology Arctic Axel Heiberg Island glacier* Cambridge University Press Arctic Canada Heiberg ENVELOPE(13.964,13.964,66.424,66.424) Axel Heiberg Island ENVELOPE(-91.001,-91.001,79.752,79.752) Marginal Lake ENVELOPE(163.500,163.500,-74.600,-74.600) White Glacier ENVELOPE(-90.667,-90.667,79.447,79.447) Annals of Glaciology 58 75pt2 145 154 |
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Open Polar |
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Cambridge University Press |
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crcambridgeupr |
language |
English |
description |
ABSTRACT As the focus of intensive glaciological studies in the 1960–70s, White Glacier on Axel Heiberg Island, Canada, has played an important role in understanding the dynamics of mostly-cold polythermal glaciers in the high Arctic. In this study, we examine the magnitude, duration and timing of peak velocity events in the summers of 2013–15 using continuous dual-frequency GPS observations, and compare them with similar measurements made in 1968. Summer speed-up events in 1968 and 2014, in which ice velocities reached 200% above winter values, were found to occur in conjunction with formation and drainage of an ice-marginal lake. Despite thinning of the glacier by >20 m and a decrease in annual surface velocities of 15–35% since the 1960s, the relative magnitude and duration of these peak events has increased, particularly at lower elevations, in comparison with the observations at the same locations many decades ago. Given the long-term slowdown of the glacier, the relative contribution of summer displacement to the net annual motion has therefore increased significantly, with summer motion over the span of <2 months now accounting for nearly half of the total annual displacement. |
format |
Article in Journal/Newspaper |
author |
Thomson, Laura I. Copland, Luke |
spellingShingle |
Thomson, Laura I. Copland, Luke Changing contribution of peak velocity events to annual velocities following a multi-decadal slowdown at White Glacier |
author_facet |
Thomson, Laura I. Copland, Luke |
author_sort |
Thomson, Laura I. |
title |
Changing contribution of peak velocity events to annual velocities following a multi-decadal slowdown at White Glacier |
title_short |
Changing contribution of peak velocity events to annual velocities following a multi-decadal slowdown at White Glacier |
title_full |
Changing contribution of peak velocity events to annual velocities following a multi-decadal slowdown at White Glacier |
title_fullStr |
Changing contribution of peak velocity events to annual velocities following a multi-decadal slowdown at White Glacier |
title_full_unstemmed |
Changing contribution of peak velocity events to annual velocities following a multi-decadal slowdown at White Glacier |
title_sort |
changing contribution of peak velocity events to annual velocities following a multi-decadal slowdown at white glacier |
publisher |
Cambridge University Press (CUP) |
publishDate |
2017 |
url |
http://dx.doi.org/10.1017/aog.2017.46 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0260305517000465 |
long_lat |
ENVELOPE(13.964,13.964,66.424,66.424) ENVELOPE(-91.001,-91.001,79.752,79.752) ENVELOPE(163.500,163.500,-74.600,-74.600) ENVELOPE(-90.667,-90.667,79.447,79.447) |
geographic |
Arctic Canada Heiberg Axel Heiberg Island Marginal Lake White Glacier |
geographic_facet |
Arctic Canada Heiberg Axel Heiberg Island Marginal Lake White Glacier |
genre |
Annals of Glaciology Arctic Axel Heiberg Island glacier* |
genre_facet |
Annals of Glaciology Arctic Axel Heiberg Island glacier* |
op_source |
Annals of Glaciology volume 58, issue 75pt2, page 145-154 ISSN 0260-3055 1727-5644 |
op_rights |
http://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.1017/aog.2017.46 |
container_title |
Annals of Glaciology |
container_volume |
58 |
container_issue |
75pt2 |
container_start_page |
145 |
op_container_end_page |
154 |
_version_ |
1801373180480192512 |