Interannual changes in seasonal ground freezing and near‐surface heat flow beneath bottom‐fast ice in the near‐shore zone, Mackenzie Delta, NWT, Canada
Abstract Interannual changes in seasonal ground freezing and near‐surface heat flow beneath zones of bottom‐fast ice (BFI) were examined over the winters of 2005–06 and 2006–07 within the near‐shore zone of the Mackenzie Delta, Canada. Winter variability in ground thermal conditions was determined a...
Published in: | Permafrost and Periglacial Processes |
---|---|
Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Wiley
2010
|
Subjects: | |
Online Access: | http://dx.doi.org/10.1002/ppp.682 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fppp.682 https://onlinelibrary.wiley.com/doi/pdf/10.1002/ppp.682 |
id |
crwiley:10.1002/ppp.682 |
---|---|
record_format |
openpolar |
spelling |
crwiley:10.1002/ppp.682 2024-06-23T07:53:38+00:00 Interannual changes in seasonal ground freezing and near‐surface heat flow beneath bottom‐fast ice in the near‐shore zone, Mackenzie Delta, NWT, Canada Stevens, Christopher W. Moorman, Brian J. Solomon, Steve M. 2010 http://dx.doi.org/10.1002/ppp.682 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fppp.682 https://onlinelibrary.wiley.com/doi/pdf/10.1002/ppp.682 en eng Wiley http://onlinelibrary.wiley.com/termsAndConditions#vor Permafrost and Periglacial Processes volume 21, issue 3, page 256-270 ISSN 1045-6740 1099-1530 journal-article 2010 crwiley https://doi.org/10.1002/ppp.682 2024-06-13T04:25:01Z Abstract Interannual changes in seasonal ground freezing and near‐surface heat flow beneath zones of bottom‐fast ice (BFI) were examined over the winters of 2005–06 and 2006–07 within the near‐shore zone of the Mackenzie Delta, Canada. Winter variability in ground thermal conditions was determined at three monitoring sites. Ground‐penetrating radar surveys were conducted in late winter to determine spatial variability in landfast ice conditions and the extent of ice‐bonded sediments. Shallow water sites (<0.5 m‐water depth) were characterised by early onset of BFI, freezeback of the active layer and mean winter sediment bed temperatures ranging between −3°C and −10°C. In contrast, deep water sites (>1 m of water) experienced prolonged periods of floating ice, which limited the duration of ice contact with the sediment bed and the depth of seasonal frost, and resulted in warmer winter ground temperatures (between −0.5°C and −2.6°C). Under similar water depths, interannual changes in ice growth altered the timing of BFI and winter heat loss from the ground. When comparing conditions over the two winters, 2005–06 was characterised by a decrease in ice thickness that limited the extent of BFI and seasonal cooling of the ground. These changes in ice conditions had a greater effect on the thermal conditions at sites where water depths were close to the maximum ice thickness. The short ice contact times at these sites are important to the thermal state of permafrost, as only minimal heat exchange contributing to permafrost cooling occurs prior to freezeback of the active layer. Copyright © 2010 John Wiley & Sons, Ltd. Article in Journal/Newspaper Ice Mackenzie Delta permafrost Permafrost and Periglacial Processes Wiley Online Library Canada Mackenzie Delta ENVELOPE(-136.672,-136.672,68.833,68.833) Permafrost and Periglacial Processes 21 3 256 270 |
institution |
Open Polar |
collection |
Wiley Online Library |
op_collection_id |
crwiley |
language |
English |
description |
Abstract Interannual changes in seasonal ground freezing and near‐surface heat flow beneath zones of bottom‐fast ice (BFI) were examined over the winters of 2005–06 and 2006–07 within the near‐shore zone of the Mackenzie Delta, Canada. Winter variability in ground thermal conditions was determined at three monitoring sites. Ground‐penetrating radar surveys were conducted in late winter to determine spatial variability in landfast ice conditions and the extent of ice‐bonded sediments. Shallow water sites (<0.5 m‐water depth) were characterised by early onset of BFI, freezeback of the active layer and mean winter sediment bed temperatures ranging between −3°C and −10°C. In contrast, deep water sites (>1 m of water) experienced prolonged periods of floating ice, which limited the duration of ice contact with the sediment bed and the depth of seasonal frost, and resulted in warmer winter ground temperatures (between −0.5°C and −2.6°C). Under similar water depths, interannual changes in ice growth altered the timing of BFI and winter heat loss from the ground. When comparing conditions over the two winters, 2005–06 was characterised by a decrease in ice thickness that limited the extent of BFI and seasonal cooling of the ground. These changes in ice conditions had a greater effect on the thermal conditions at sites where water depths were close to the maximum ice thickness. The short ice contact times at these sites are important to the thermal state of permafrost, as only minimal heat exchange contributing to permafrost cooling occurs prior to freezeback of the active layer. Copyright © 2010 John Wiley & Sons, Ltd. |
format |
Article in Journal/Newspaper |
author |
Stevens, Christopher W. Moorman, Brian J. Solomon, Steve M. |
spellingShingle |
Stevens, Christopher W. Moorman, Brian J. Solomon, Steve M. Interannual changes in seasonal ground freezing and near‐surface heat flow beneath bottom‐fast ice in the near‐shore zone, Mackenzie Delta, NWT, Canada |
author_facet |
Stevens, Christopher W. Moorman, Brian J. Solomon, Steve M. |
author_sort |
Stevens, Christopher W. |
title |
Interannual changes in seasonal ground freezing and near‐surface heat flow beneath bottom‐fast ice in the near‐shore zone, Mackenzie Delta, NWT, Canada |
title_short |
Interannual changes in seasonal ground freezing and near‐surface heat flow beneath bottom‐fast ice in the near‐shore zone, Mackenzie Delta, NWT, Canada |
title_full |
Interannual changes in seasonal ground freezing and near‐surface heat flow beneath bottom‐fast ice in the near‐shore zone, Mackenzie Delta, NWT, Canada |
title_fullStr |
Interannual changes in seasonal ground freezing and near‐surface heat flow beneath bottom‐fast ice in the near‐shore zone, Mackenzie Delta, NWT, Canada |
title_full_unstemmed |
Interannual changes in seasonal ground freezing and near‐surface heat flow beneath bottom‐fast ice in the near‐shore zone, Mackenzie Delta, NWT, Canada |
title_sort |
interannual changes in seasonal ground freezing and near‐surface heat flow beneath bottom‐fast ice in the near‐shore zone, mackenzie delta, nwt, canada |
publisher |
Wiley |
publishDate |
2010 |
url |
http://dx.doi.org/10.1002/ppp.682 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fppp.682 https://onlinelibrary.wiley.com/doi/pdf/10.1002/ppp.682 |
long_lat |
ENVELOPE(-136.672,-136.672,68.833,68.833) |
geographic |
Canada Mackenzie Delta |
geographic_facet |
Canada Mackenzie Delta |
genre |
Ice Mackenzie Delta permafrost Permafrost and Periglacial Processes |
genre_facet |
Ice Mackenzie Delta permafrost Permafrost and Periglacial Processes |
op_source |
Permafrost and Periglacial Processes volume 21, issue 3, page 256-270 ISSN 1045-6740 1099-1530 |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.1002/ppp.682 |
container_title |
Permafrost and Periglacial Processes |
container_volume |
21 |
container_issue |
3 |
container_start_page |
256 |
op_container_end_page |
270 |
_version_ |
1802645380398055424 |