Dynamics and Historical Changes of the Petersen Ice Shelf and Epishelf Lake, Nunavut, Canada, since 1959
This study presents the first comprehensive assessment of the Petersen Ice Shelf and the Petersen Bay epishelf lake, and examines their current characteristics and changes to their structure between 1959 and 2012. The surface of the Petersen Ice Shelf is characterized by a rolling topography of ridg...
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ftcanadathes:oai:collectionscanada.gc.ca:OOU.#10393/23574 2023-05-15T16:05:57+02:00 Dynamics and Historical Changes of the Petersen Ice Shelf and Epishelf Lake, Nunavut, Canada, since 1959 White, Adrienne 2012-12-07T19:08:43Z http://hdl.handle.net/10393/23574 en eng http://hdl.handle.net/10393/23574 Ice shelf Epishelf lake Ellesmere Island Ground penetrating radar Remote sensing Thèse / Thesis 2012 ftcanadathes 2014-06-14T23:47:23Z This study presents the first comprehensive assessment of the Petersen Ice Shelf and the Petersen Bay epishelf lake, and examines their current characteristics and changes to their structure between 1959 and 2012. The surface of the Petersen Ice Shelf is characterized by a rolling topography of ridges and troughs, which is balanced by a rolling basal topography, with thicker ice under the surface ridges and thinner ice under the surface troughs. Based on thickness measurements collected in 2011 and area measurements from August 2012, the Petersen Ice Shelf has a surface area of 19.32 km2 and a mean thickness of 29 m, with the greatest thicknesses (>100 m) occurring at the fronts of tributary glaciers feeding into the ice shelf. The tributary glaciers along the northern coast of Petersen Bay contributed an estimated area-averaged 7.89 to 13.55 cm yr-1 of ice to the ice shelf between 2011 and 2012. This input is counteracted by a mean surface ablation of 1.30 m yr-1 between 2011 and 2012, suggesting strongly negative current mass balance conditions on the ice shelf. The Petersen Ice Shelf remained relatively stable until 2005 when the first break-up in recent history occurred, removing >8 km2 of ice shelf surface area. This break-up led to the drainage of the epishelf lake once the ice shelf separated from the southern coast, providing a conduit through which the freshwater from the lake escaped. More break-ups occurred in summers 2008, 2011 and 2012, which resulted in a >31.2 km2 loss in surface area (~63% of June 2005 area). While ephemeral regions of freshwater have occurred along the southern coast of Petersen Bay since 2005 (with areas ranging from 0.32-0.53 km2), open water events and a channel along the southern coast have prevented the epishelf lake from reforming. Based on these past and present observations it is unlikely that Petersen Ice Shelf will continue to persist long into the future. Thesis Ellesmere Island glacier* Ice Shelf Nunavut Theses Canada/Thèses Canada (Library and Archives Canada) Canada Ellesmere Island Nunavut Petersen ENVELOPE(-101.250,-101.250,-71.917,-71.917) |
institution |
Open Polar |
collection |
Theses Canada/Thèses Canada (Library and Archives Canada) |
op_collection_id |
ftcanadathes |
language |
English |
topic |
Ice shelf Epishelf lake Ellesmere Island Ground penetrating radar Remote sensing |
spellingShingle |
Ice shelf Epishelf lake Ellesmere Island Ground penetrating radar Remote sensing White, Adrienne Dynamics and Historical Changes of the Petersen Ice Shelf and Epishelf Lake, Nunavut, Canada, since 1959 |
topic_facet |
Ice shelf Epishelf lake Ellesmere Island Ground penetrating radar Remote sensing |
description |
This study presents the first comprehensive assessment of the Petersen Ice Shelf and the Petersen Bay epishelf lake, and examines their current characteristics and changes to their structure between 1959 and 2012. The surface of the Petersen Ice Shelf is characterized by a rolling topography of ridges and troughs, which is balanced by a rolling basal topography, with thicker ice under the surface ridges and thinner ice under the surface troughs. Based on thickness measurements collected in 2011 and area measurements from August 2012, the Petersen Ice Shelf has a surface area of 19.32 km2 and a mean thickness of 29 m, with the greatest thicknesses (>100 m) occurring at the fronts of tributary glaciers feeding into the ice shelf. The tributary glaciers along the northern coast of Petersen Bay contributed an estimated area-averaged 7.89 to 13.55 cm yr-1 of ice to the ice shelf between 2011 and 2012. This input is counteracted by a mean surface ablation of 1.30 m yr-1 between 2011 and 2012, suggesting strongly negative current mass balance conditions on the ice shelf. The Petersen Ice Shelf remained relatively stable until 2005 when the first break-up in recent history occurred, removing >8 km2 of ice shelf surface area. This break-up led to the drainage of the epishelf lake once the ice shelf separated from the southern coast, providing a conduit through which the freshwater from the lake escaped. More break-ups occurred in summers 2008, 2011 and 2012, which resulted in a >31.2 km2 loss in surface area (~63% of June 2005 area). While ephemeral regions of freshwater have occurred along the southern coast of Petersen Bay since 2005 (with areas ranging from 0.32-0.53 km2), open water events and a channel along the southern coast have prevented the epishelf lake from reforming. Based on these past and present observations it is unlikely that Petersen Ice Shelf will continue to persist long into the future. |
format |
Thesis |
author |
White, Adrienne |
author_facet |
White, Adrienne |
author_sort |
White, Adrienne |
title |
Dynamics and Historical Changes of the Petersen Ice Shelf and Epishelf Lake, Nunavut, Canada, since 1959 |
title_short |
Dynamics and Historical Changes of the Petersen Ice Shelf and Epishelf Lake, Nunavut, Canada, since 1959 |
title_full |
Dynamics and Historical Changes of the Petersen Ice Shelf and Epishelf Lake, Nunavut, Canada, since 1959 |
title_fullStr |
Dynamics and Historical Changes of the Petersen Ice Shelf and Epishelf Lake, Nunavut, Canada, since 1959 |
title_full_unstemmed |
Dynamics and Historical Changes of the Petersen Ice Shelf and Epishelf Lake, Nunavut, Canada, since 1959 |
title_sort |
dynamics and historical changes of the petersen ice shelf and epishelf lake, nunavut, canada, since 1959 |
publishDate |
2012 |
url |
http://hdl.handle.net/10393/23574 |
long_lat |
ENVELOPE(-101.250,-101.250,-71.917,-71.917) |
geographic |
Canada Ellesmere Island Nunavut Petersen |
geographic_facet |
Canada Ellesmere Island Nunavut Petersen |
genre |
Ellesmere Island glacier* Ice Shelf Nunavut |
genre_facet |
Ellesmere Island glacier* Ice Shelf Nunavut |
op_relation |
http://hdl.handle.net/10393/23574 |
_version_ |
1766401870059798528 |