DOI: 10.5194/tc-11-1351-2017
Scopus记录号: 2-s2.0-85020665685
论文题名: Wind-driven snow conditions control the occurrence of contemporary marginal mountain permafrost in the Chic-Choc Mountains, south-eastern Canada: A case study from Mont Jacques-Cartier
作者: Davesne G ; , Fortier D ; , Domine F ; , Gray J ; T
刊名: Cryosphere
ISSN: 19940416
出版年: 2017
卷: 11, 期: 3 起始页码: 1351
结束页码: 1370
语种: 英语
英文关键词: air temperature
; arctic environment
; climate conditions
; heat transfer
; herb
; mountain environment
; permafrost
; snow
; snow cover
; snowpack
; spatial distribution
; surface temperature
; tundra
; Appalachians
; Canada
; Chic-Chocs Mountains
; Quebec [Canada]
; Picea
英文摘要: We present data on the distribution and thermophysical properties of snow collected sporadically over 4 decades along with recent data of ground surface temperature from Mont Jacques-Cartier (1268ma.s.l.), the highest summit in the Appalachians of south-eastern Canada. We demonstrate that the occurrence of contemporary permafrost is necessarily associated with a very thin and wind-packed winter snow cover which brings local azonal topo-climatic conditions on the dome-shaped summit. The aims of this study were (i) to understand the snow distribution pattern and snow thermophysical properties on the Mont Jacques-Cartier summit and (ii) to investigate the impact of snow on the spatial distribution of the ground surface temperature (GST) using temperature sensors deployed over the summit. Results showed that above the local treeline, the summit is characterized by a snow cover typically less than 30 cm thick which is explained by the strong westerly winds interacting with the local surface roughness created by the physiography and surficial geomorphology of the site. The snowpack structure is fairly similar to that observed on windy Arctic tundra with a top dense wind slab (300 to 450 kgm-3) of high thermal conductivity, which facilitates heat transfer between the ground surface and the atmosphere. The mean annual ground surface temperature (MAGST) below this thin and wind-packed snow cover was about -1 °C in 2013 and 2014, for the higher, exposed, blockfield-covered sector of the summit characterized by a sporadic herbaceous cover. In contrast, for the gentle slopes covered with stunted spruce (krummholz), and for the steep leeward slope to the southeast of the summit, the MAGST was around 3 °C in 2013 and 2014. The study concludes that the permafrost on Mont Jacques-Cartier, most widely in the Chic-Choc Mountains and by extension in the southern highest summits of the Appalachians, is therefore likely limited to the barren windexposed surface of the summit where the low air temperature, the thin snowpack and the wind action bring local cold surface conditions favourable to permafrost development. © Author(s) 2017. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/75544
Appears in Collections: 影响、适应和脆弱性 气候变化与战略
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作者单位: Cold Regions Geomorphology and Geotechnical Laboratory, Département de Géographie, Université de Montréal, Montréal, QC, Canada; Centre for Northern Studies, Université LavalQC, Canada; Takuvik Joint International Laboratory, Université Laval, Centre National de Recherche Scientifique, Département de Chimie, Université LavalQC, Canada
Recommended Citation:
Davesne G,, Fortier D,, Domine F,et al. Wind-driven snow conditions control the occurrence of contemporary marginal mountain permafrost in the Chic-Choc Mountains, south-eastern Canada: A case study from Mont Jacques-Cartier[J]. Cryosphere,2017-01-01,11(3)