Tundra lakes and permafrost, Richards Island, Western Arctic coast, Canada
Lakes, of average size 33 ha, occupy a quarter of the surface area of Richards Island, Northwest Territories. Most of the lakes have a central pool deeper than the thickness of winter ice, and many have prominent, shallow, littoral terraces. The relatively warm lake bottoms cause considerable distur...
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ftcarletonunivir:oai:carleton.ca:1773 2023-05-15T13:03:15+02:00 Tundra lakes and permafrost, Richards Island, Western Arctic coast, Canada Burn, C. (Christopher R.) 2002-10-01 https://ir.library.carleton.ca/pub/1773 https://doi.org/10.1139/e02-035 en eng https://ir.library.carleton.ca/pub/1773 doi:10.1139/e02-035 Canadian Journal of Earth Sciences vol. 39 no. 8, pp. 1281-1298 info:eu-repo/semantics/article 2002 ftcarletonunivir https://doi.org/10.1139/e02-035 2022-02-06T21:51:35Z Lakes, of average size 33 ha, occupy a quarter of the surface area of Richards Island, Northwest Territories. Most of the lakes have a central pool deeper than the thickness of winter ice, and many have prominent, shallow, littoral terraces. The relatively warm lake bottoms cause considerable disturbance to the surrounding continuous permafrost. Water and lake-bottom temperatures, the configuration of permafrost, and active-layer thickness were measured at a tundra lake between 1992 and 1997. The lake is oval, 1.6 km long, 800 m wide, and as deep as 13 m. Sandy terraces, covered by less than 1 m of water, extend over 100 m from the shore. The terraces are underlain by permafrost, which terminates almost vertically at their edge. The annual mean temperature measured at lake bottom in the central pool ranged between 1.5°C and 4.8°C, depending on depth, and between -0.2°C and -5°C on the terraces, due to differences in snow cover and proximity to the central pool. In consequence, the temperature of permafrost at 7 m depth in the terraces also varied, from -2°C near shore to -5°C in mid-terrace. The active layer in the terraces was uniformly 1.4 m deep. Geothermal modelling of talik configuration indicates that there is no permafrost beneath the central pool of the lake. The modelling indicates that, under equilibrium conditions, about one quarter of the lakes on Richards Island have taliks that penetrate permafrost, and at least 10-15% of the island is underlain by talik. Short-term climatic changes predicted for the region imply a small increase in summer lake-water temperature and an extension of the open-water season, accompanied by thicker snow cover in winter. Following such changes, with longer freeze-up and warmer terrace temperatures in winter, permafrost may not be sustainable in the lake terraces. Article in Journal/Newspaper Active layer thickness Arctic Ice Northwest Territories permafrost Richards Island Talik Tundra Carleton University's Institutional Repository Arctic Northwest Territories Canada Talik ENVELOPE(146.601,146.601,59.667,59.667) Canadian Journal of Earth Sciences 39 8 1281 1298 |
institution |
Open Polar |
collection |
Carleton University's Institutional Repository |
op_collection_id |
ftcarletonunivir |
language |
English |
description |
Lakes, of average size 33 ha, occupy a quarter of the surface area of Richards Island, Northwest Territories. Most of the lakes have a central pool deeper than the thickness of winter ice, and many have prominent, shallow, littoral terraces. The relatively warm lake bottoms cause considerable disturbance to the surrounding continuous permafrost. Water and lake-bottom temperatures, the configuration of permafrost, and active-layer thickness were measured at a tundra lake between 1992 and 1997. The lake is oval, 1.6 km long, 800 m wide, and as deep as 13 m. Sandy terraces, covered by less than 1 m of water, extend over 100 m from the shore. The terraces are underlain by permafrost, which terminates almost vertically at their edge. The annual mean temperature measured at lake bottom in the central pool ranged between 1.5°C and 4.8°C, depending on depth, and between -0.2°C and -5°C on the terraces, due to differences in snow cover and proximity to the central pool. In consequence, the temperature of permafrost at 7 m depth in the terraces also varied, from -2°C near shore to -5°C in mid-terrace. The active layer in the terraces was uniformly 1.4 m deep. Geothermal modelling of talik configuration indicates that there is no permafrost beneath the central pool of the lake. The modelling indicates that, under equilibrium conditions, about one quarter of the lakes on Richards Island have taliks that penetrate permafrost, and at least 10-15% of the island is underlain by talik. Short-term climatic changes predicted for the region imply a small increase in summer lake-water temperature and an extension of the open-water season, accompanied by thicker snow cover in winter. Following such changes, with longer freeze-up and warmer terrace temperatures in winter, permafrost may not be sustainable in the lake terraces. |
format |
Article in Journal/Newspaper |
author |
Burn, C. (Christopher R.) |
spellingShingle |
Burn, C. (Christopher R.) Tundra lakes and permafrost, Richards Island, Western Arctic coast, Canada |
author_facet |
Burn, C. (Christopher R.) |
author_sort |
Burn, C. (Christopher R.) |
title |
Tundra lakes and permafrost, Richards Island, Western Arctic coast, Canada |
title_short |
Tundra lakes and permafrost, Richards Island, Western Arctic coast, Canada |
title_full |
Tundra lakes and permafrost, Richards Island, Western Arctic coast, Canada |
title_fullStr |
Tundra lakes and permafrost, Richards Island, Western Arctic coast, Canada |
title_full_unstemmed |
Tundra lakes and permafrost, Richards Island, Western Arctic coast, Canada |
title_sort |
tundra lakes and permafrost, richards island, western arctic coast, canada |
publishDate |
2002 |
url |
https://ir.library.carleton.ca/pub/1773 https://doi.org/10.1139/e02-035 |
long_lat |
ENVELOPE(146.601,146.601,59.667,59.667) |
geographic |
Arctic Northwest Territories Canada Talik |
geographic_facet |
Arctic Northwest Territories Canada Talik |
genre |
Active layer thickness Arctic Ice Northwest Territories permafrost Richards Island Talik Tundra |
genre_facet |
Active layer thickness Arctic Ice Northwest Territories permafrost Richards Island Talik Tundra |
op_source |
Canadian Journal of Earth Sciences vol. 39 no. 8, pp. 1281-1298 |
op_relation |
https://ir.library.carleton.ca/pub/1773 doi:10.1139/e02-035 |
op_doi |
https://doi.org/10.1139/e02-035 |
container_title |
Canadian Journal of Earth Sciences |
container_volume |
39 |
container_issue |
8 |
container_start_page |
1281 |
op_container_end_page |
1298 |
_version_ |
1766332381527015424 |