Automatic monitoring of the effective thermal conductivity of snow in a low-Arctic shrub tundra
The effective thermal conductivity of snow, keff, is a critical variable which determines the temperature gradient in the snowpack and heat exchanges between the ground and the atmosphere through the snow. Its accurate knowledge is therefore required to simulate snow metamorphism, the ground thermal...
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Copernicus Publications
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fttriple:oai:gotriple.eu:oai:doaj.org/article:01ff71f448c94876ad540ac2c2955be1 2023-05-15T14:54:45+02:00 Automatic monitoring of the effective thermal conductivity of snow in a low-Arctic shrub tundra F. Domine M. Barrere D. Sarrazin S. Morin L. Arnaud 2015-06-01 https://doi.org/10.5194/tc-9-1265-2015 http://www.the-cryosphere.net/9/1265/2015/tc-9-1265-2015.pdf https://doaj.org/article/01ff71f448c94876ad540ac2c2955be1 en eng Copernicus Publications 1994-0416 1994-0424 doi:10.5194/tc-9-1265-2015 http://www.the-cryosphere.net/9/1265/2015/tc-9-1265-2015.pdf https://doaj.org/article/01ff71f448c94876ad540ac2c2955be1 undefined The Cryosphere, Vol 9, Iss 3, Pp 1265-1276 (2015) geo envir Journal Article https://vocabularies.coar-repositories.org/resource_types/c_6501/ 2015 fttriple https://doi.org/10.5194/tc-9-1265-2015 2023-01-22T18:19:06Z The effective thermal conductivity of snow, keff, is a critical variable which determines the temperature gradient in the snowpack and heat exchanges between the ground and the atmosphere through the snow. Its accurate knowledge is therefore required to simulate snow metamorphism, the ground thermal regime, permafrost stability, nutrient recycling and vegetation growth. Yet, few data are available on the seasonal evolution of snow thermal conductivity in the Arctic. We have deployed heated needle probes on low-Arctic shrub tundra near Umiujaq, Quebec, (N56°34'; W76°29') and monitored automatically the evolution of keff for two consecutive winters, 2012–2013 and 2013–2014, at four heights in the snowpack. Shrubs are 20 cm high dwarf birch. Here, we develop an algorithm for the automatic determination of keff from the heating curves and obtain 404 keff values. We evaluate possible errors and biases associated with the use of the heated needles. The time evolution of keff is very different for both winters. This is explained by comparing the meteorological conditions in both winters, which induced different conditions for snow metamorphism. In particular, important melting events in the second year increased snow hardness, impeding subsequent densification and increase in thermal conductivity. We conclude that shrubs have very important impacts on snow physical evolution: (1) shrubs absorb light and facilitate snow melt under intense radiation; (2) the dense twig network of dwarf birch prevent snow compaction, and therefore keff increase; (3) the low density depth hoar that forms within shrubs collapsed in late winter, leaving a void that was not filled by snow. Article in Journal/Newspaper Arctic Dwarf birch permafrost The Cryosphere Tundra Umiujaq Unknown Arctic Needles The ENVELOPE(-70.967,-70.967,-68.950,-68.950) Umiujaq ENVELOPE(-76.549,-76.549,56.553,56.553) The Cryosphere 9 3 1265 1276 |
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English |
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geo envir F. Domine M. Barrere D. Sarrazin S. Morin L. Arnaud Automatic monitoring of the effective thermal conductivity of snow in a low-Arctic shrub tundra |
topic_facet |
geo envir |
description |
The effective thermal conductivity of snow, keff, is a critical variable which determines the temperature gradient in the snowpack and heat exchanges between the ground and the atmosphere through the snow. Its accurate knowledge is therefore required to simulate snow metamorphism, the ground thermal regime, permafrost stability, nutrient recycling and vegetation growth. Yet, few data are available on the seasonal evolution of snow thermal conductivity in the Arctic. We have deployed heated needle probes on low-Arctic shrub tundra near Umiujaq, Quebec, (N56°34'; W76°29') and monitored automatically the evolution of keff for two consecutive winters, 2012–2013 and 2013–2014, at four heights in the snowpack. Shrubs are 20 cm high dwarf birch. Here, we develop an algorithm for the automatic determination of keff from the heating curves and obtain 404 keff values. We evaluate possible errors and biases associated with the use of the heated needles. The time evolution of keff is very different for both winters. This is explained by comparing the meteorological conditions in both winters, which induced different conditions for snow metamorphism. In particular, important melting events in the second year increased snow hardness, impeding subsequent densification and increase in thermal conductivity. We conclude that shrubs have very important impacts on snow physical evolution: (1) shrubs absorb light and facilitate snow melt under intense radiation; (2) the dense twig network of dwarf birch prevent snow compaction, and therefore keff increase; (3) the low density depth hoar that forms within shrubs collapsed in late winter, leaving a void that was not filled by snow. |
format |
Article in Journal/Newspaper |
author |
F. Domine M. Barrere D. Sarrazin S. Morin L. Arnaud |
author_facet |
F. Domine M. Barrere D. Sarrazin S. Morin L. Arnaud |
author_sort |
F. Domine |
title |
Automatic monitoring of the effective thermal conductivity of snow in a low-Arctic shrub tundra |
title_short |
Automatic monitoring of the effective thermal conductivity of snow in a low-Arctic shrub tundra |
title_full |
Automatic monitoring of the effective thermal conductivity of snow in a low-Arctic shrub tundra |
title_fullStr |
Automatic monitoring of the effective thermal conductivity of snow in a low-Arctic shrub tundra |
title_full_unstemmed |
Automatic monitoring of the effective thermal conductivity of snow in a low-Arctic shrub tundra |
title_sort |
automatic monitoring of the effective thermal conductivity of snow in a low-arctic shrub tundra |
publisher |
Copernicus Publications |
publishDate |
2015 |
url |
https://doi.org/10.5194/tc-9-1265-2015 http://www.the-cryosphere.net/9/1265/2015/tc-9-1265-2015.pdf https://doaj.org/article/01ff71f448c94876ad540ac2c2955be1 |
long_lat |
ENVELOPE(-70.967,-70.967,-68.950,-68.950) ENVELOPE(-76.549,-76.549,56.553,56.553) |
geographic |
Arctic Needles The Umiujaq |
geographic_facet |
Arctic Needles The Umiujaq |
genre |
Arctic Dwarf birch permafrost The Cryosphere Tundra Umiujaq |
genre_facet |
Arctic Dwarf birch permafrost The Cryosphere Tundra Umiujaq |
op_source |
The Cryosphere, Vol 9, Iss 3, Pp 1265-1276 (2015) |
op_relation |
1994-0416 1994-0424 doi:10.5194/tc-9-1265-2015 http://www.the-cryosphere.net/9/1265/2015/tc-9-1265-2015.pdf https://doaj.org/article/01ff71f448c94876ad540ac2c2955be1 |
op_rights |
undefined |
op_doi |
https://doi.org/10.5194/tc-9-1265-2015 |
container_title |
The Cryosphere |
container_volume |
9 |
container_issue |
3 |
container_start_page |
1265 |
op_container_end_page |
1276 |
_version_ |
1766326505882779648 |