气候变化领域集成服务门户(CCPortal): Observation and modelling of snow at a polygonal tundra permafrost site: Spatial variability and thermal implications

CCPortal

DOI	10.5194/tc-12-3693-2018
	Observation and modelling of snow at a polygonal tundra permafrost site: Spatial variability and thermal implications
	Gouttevin I.; Langer M.; Löwe H.; Boike J.; Proksch M.; Schneebeli M.
发表日期	2018
ISSN	19940416
卷号	12 期号:11
英文摘要	The shortage of information on snow properties in high latitudes places a major limitation on permafrost and more generally climate modelling. A dedicated field program was therefore carried out to investigate snow properties and their spatial variability at a polygonal tundra permafrost site. Notably, snow samples were analysed for surface-normal thermal conductivity (Keff-z) based on X-ray microtomography. Also, the detailed snow model SNOWPACK was adapted to these Arctic conditions to enable relevant simulations of the ground thermal regime. Finally, the sensitivity of soil temperatures to snow spatial variability was analysed. Within a typical tundra snowpack composed of depth hoar overlain by wind slabs, depth hoar samples were found more conductive (Keff-z = 0.22±0.05 Wm-1K-1) than in most previously published studies, which could be explained by their high density and microstructural anisotropy. Spatial variations in the thermal properties of the snowpack were well explained by the microtopography and ground surface conditions of the polygonal tundra, which control depth hoar growth and snow accumulation. Our adaptations to SNOWPACK, phenomenologically taking into account the effects of wind compaction, basal vegetation, and water vapour flux, yielded realistic density and K Keff-z profiles that greatly improved simulations of the ground thermal regime. Also, a density- and anisotropy-based parameterization for Keff-z lead to further slight improvements. Soil temperatures were found to be particularly sensitive to snow conditions during the early winter and polar night, highlighting the need for improved snow characterization and modelling over this period. © 2018 E-flow Copernicus GmbH. All rights reserved.
学科领域	climate modeling; hydrological modeling; latitude; microtopography; observatory; parameterization; permafrost; snow; snowpack; soil temperature; spatial variation; thermal conductivity; thermal regime; tundra; Arctic
语种	英语
scopus关键词	climate modeling; hydrological modeling; latitude; microtopography; observatory; parameterization; permafrost; snow; snowpack; soil temperature; spatial variation; thermal conductivity; thermal regime; tundra; Arctic
来源期刊	Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/119025
作者单位	Irstea, UR HHLY, Centre de Lyon-Villeurbanne, 5 Rue de la Doua, BP 32108, Villeurbanne cedex, 69616, France; Université Grenoble Alpes, Irstea, UR ETGR, Centre de Grenoble, 2 rue de la Papeterie-BP 76, St-Martin-d'Hères, 38402, France; Alfred Wegener Institute, Helmholtz Center for Polar and Marine Research (AWI), Telegrafenberg A6, Potsdam, 14473, Germany; Department of Geography, Humboldt-Universität zu Berlin, Rudower Chaussee 16, Berlin, 12489, Germany; WSL Institute for Snow and Avalanche Research SLF, Flueelastr. 11, Davos Dorf, 7260, Switzerland; Univ. Grenoble Alpes, Université de Toulouse, Météo-France, CNRS, CNRM, Centre d'Etudes de la Neige, Grenoble, France
推荐引用方式 GB/T 7714	Gouttevin I.,Langer M.,Löwe H.,et al. Observation and modelling of snow at a polygonal tundra permafrost site: Spatial variability and thermal implications[J],2018,12(11).
APA	Gouttevin I.,Langer M.,Löwe H.,Boike J.,Proksch M.,&Schneebeli M..(2018).Observation and modelling of snow at a polygonal tundra permafrost site: Spatial variability and thermal implications.Cryosphere,12(11).
MLA	Gouttevin I.,et al."Observation and modelling of snow at a polygonal tundra permafrost site: Spatial variability and thermal implications".Cryosphere 12.11(2018).