Automatic monitoring of the effective thermal conductivity of snow in a low-Arctic shrub tundra
The effective thermal conductivity of snow, k eff , 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 therm...
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ftdoajarticles:oai:doaj.org/article:01ff71f448c94876ad540ac2c2955be1 2023-05-15T14:55:49+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 2015-06-01T00:00:00Z https://doi.org/10.5194/tc-9-1265-2015 https://doaj.org/article/01ff71f448c94876ad540ac2c2955be1 EN eng Copernicus Publications http://www.the-cryosphere.net/9/1265/2015/tc-9-1265-2015.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 1994-0416 1994-0424 doi:10.5194/tc-9-1265-2015 https://doaj.org/article/01ff71f448c94876ad540ac2c2955be1 The Cryosphere, Vol 9, Iss 3, Pp 1265-1276 (2015) Environmental sciences GE1-350 Geology QE1-996.5 article 2015 ftdoajarticles https://doi.org/10.5194/tc-9-1265-2015 2022-12-31T01:28:45Z The effective thermal conductivity of snow, k eff , 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 k eff 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 k eff from the heating curves and obtain 404 k eff values. We evaluate possible errors and biases associated with the use of the heated needles. The time evolution of k eff 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 k eff 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 Directory of Open Access Journals: DOAJ Articles 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 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
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ftdoajarticles |
language |
English |
topic |
Environmental sciences GE1-350 Geology QE1-996.5 |
spellingShingle |
Environmental sciences GE1-350 Geology QE1-996.5 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 |
Environmental sciences GE1-350 Geology QE1-996.5 |
description |
The effective thermal conductivity of snow, k eff , 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 k eff 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 k eff from the heating curves and obtain 404 k eff values. We evaluate possible errors and biases associated with the use of the heated needles. The time evolution of k eff 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 k eff 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 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 |
http://www.the-cryosphere.net/9/1265/2015/tc-9-1265-2015.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 1994-0416 1994-0424 doi:10.5194/tc-9-1265-2015 https://doaj.org/article/01ff71f448c94876ad540ac2c2955be1 |
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_ |
1766327828573323264 |