The annual surface energy budget of a high-arctic permafrost site on Svalbard, Norway
Independent measurements of radiation, sensible and latent heat fluxes and the ground heat flux are used to describe the annual cycle of the surface energy budget at a high-arctic permafrost site on Svalbard. During summer, the net short-wave radiation is the dominant energy source, while well devel...
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ftdoajarticles:oai:doaj.org/article:b8e0f80dc968418f85961ebb2cd0ffb4 2023-05-15T14:54:31+02:00 The annual surface energy budget of a high-arctic permafrost site on Svalbard, Norway S. Westermann J. Lüers M. Langer K. Piel J. Boike 2009-12-01T00:00:00Z https://doaj.org/article/b8e0f80dc968418f85961ebb2cd0ffb4 EN eng Copernicus Publications http://www.the-cryosphere.net/3/245/2009/tc-3-245-2009.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 1994-0416 1994-0424 https://doaj.org/article/b8e0f80dc968418f85961ebb2cd0ffb4 The Cryosphere, Vol 3, Iss 2, Pp 245-263 (2009) Environmental sciences GE1-350 Geology QE1-996.5 article 2009 ftdoajarticles 2022-12-31T01:46:26Z Independent measurements of radiation, sensible and latent heat fluxes and the ground heat flux are used to describe the annual cycle of the surface energy budget at a high-arctic permafrost site on Svalbard. During summer, the net short-wave radiation is the dominant energy source, while well developed turbulent processes and the heat flux in the ground lead to a cooling of the surface. About 15% of the net radiation is consumed by the seasonal thawing of the active layer in July and August. The Bowen ratio is found to vary between 0.25 and 2, depending on water content of the uppermost soil layer. During the polar night in winter, the net long-wave radiation is the dominant energy loss channel for the surface, which is mainly compensated by the sensible heat flux and, to a lesser extent, by the ground heat flux, which originates from the refreezing of the active layer. The average annual sensible heat flux of −6.9 Wm −2 is composed of strong positive fluxes in July and August, while negative fluxes dominate during the rest of the year. With 6.8 Wm −2 , the latent heat flux more or less compensates the sensible heat flux in the annual average. Strong evaporation occurs during the snow melt period and particularly during the snow-free period in summer and fall. When the ground is covered by snow, latent heat fluxes through sublimation of snow are recorded, but are insignificant for the average surface energy budget. The near-surface atmospheric stratification is found to be predominantly unstable to neutral, when the ground is snow-free, and stable to neutral for snow-covered ground. Due to long-lasting near-surface inversions in winter, an average temperature difference of approximately 3 K exists between the air temperature at 10 m height and the surface temperature of the snow. As such comprehensive data sets are sparse for the Arctic, they are of great value to improve process understanding and support modeling efforts on the present-day and future arctic climate and permafrost conditions. Article in Journal/Newspaper Arctic permafrost polar night Svalbard The Cryosphere Directory of Open Access Journals: DOAJ Articles Arctic Norway Svalbard |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Environmental sciences GE1-350 Geology QE1-996.5 |
spellingShingle |
Environmental sciences GE1-350 Geology QE1-996.5 S. Westermann J. Lüers M. Langer K. Piel J. Boike The annual surface energy budget of a high-arctic permafrost site on Svalbard, Norway |
topic_facet |
Environmental sciences GE1-350 Geology QE1-996.5 |
description |
Independent measurements of radiation, sensible and latent heat fluxes and the ground heat flux are used to describe the annual cycle of the surface energy budget at a high-arctic permafrost site on Svalbard. During summer, the net short-wave radiation is the dominant energy source, while well developed turbulent processes and the heat flux in the ground lead to a cooling of the surface. About 15% of the net radiation is consumed by the seasonal thawing of the active layer in July and August. The Bowen ratio is found to vary between 0.25 and 2, depending on water content of the uppermost soil layer. During the polar night in winter, the net long-wave radiation is the dominant energy loss channel for the surface, which is mainly compensated by the sensible heat flux and, to a lesser extent, by the ground heat flux, which originates from the refreezing of the active layer. The average annual sensible heat flux of −6.9 Wm −2 is composed of strong positive fluxes in July and August, while negative fluxes dominate during the rest of the year. With 6.8 Wm −2 , the latent heat flux more or less compensates the sensible heat flux in the annual average. Strong evaporation occurs during the snow melt period and particularly during the snow-free period in summer and fall. When the ground is covered by snow, latent heat fluxes through sublimation of snow are recorded, but are insignificant for the average surface energy budget. The near-surface atmospheric stratification is found to be predominantly unstable to neutral, when the ground is snow-free, and stable to neutral for snow-covered ground. Due to long-lasting near-surface inversions in winter, an average temperature difference of approximately 3 K exists between the air temperature at 10 m height and the surface temperature of the snow. As such comprehensive data sets are sparse for the Arctic, they are of great value to improve process understanding and support modeling efforts on the present-day and future arctic climate and permafrost conditions. |
format |
Article in Journal/Newspaper |
author |
S. Westermann J. Lüers M. Langer K. Piel J. Boike |
author_facet |
S. Westermann J. Lüers M. Langer K. Piel J. Boike |
author_sort |
S. Westermann |
title |
The annual surface energy budget of a high-arctic permafrost site on Svalbard, Norway |
title_short |
The annual surface energy budget of a high-arctic permafrost site on Svalbard, Norway |
title_full |
The annual surface energy budget of a high-arctic permafrost site on Svalbard, Norway |
title_fullStr |
The annual surface energy budget of a high-arctic permafrost site on Svalbard, Norway |
title_full_unstemmed |
The annual surface energy budget of a high-arctic permafrost site on Svalbard, Norway |
title_sort |
annual surface energy budget of a high-arctic permafrost site on svalbard, norway |
publisher |
Copernicus Publications |
publishDate |
2009 |
url |
https://doaj.org/article/b8e0f80dc968418f85961ebb2cd0ffb4 |
geographic |
Arctic Norway Svalbard |
geographic_facet |
Arctic Norway Svalbard |
genre |
Arctic permafrost polar night Svalbard The Cryosphere |
genre_facet |
Arctic permafrost polar night Svalbard The Cryosphere |
op_source |
The Cryosphere, Vol 3, Iss 2, Pp 245-263 (2009) |
op_relation |
http://www.the-cryosphere.net/3/245/2009/tc-3-245-2009.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 1994-0416 1994-0424 https://doaj.org/article/b8e0f80dc968418f85961ebb2cd0ffb4 |
_version_ |
1766326228846903296 |