DOI: 10.5194/tc-7-935-2013
Scopus记录号: 2-s2.0-84891960600
论文题名: Impacts of mean annual air temperature change on a regional permafrost probability model for the southern Yukon and northern British Columbia, Canada
作者: Bonnaventure P ; P ; , Lewkowicz A ; G
刊名: Cryosphere
ISSN: 19940416
出版年: 2013
卷: 7, 期: 3 起始页码: 935
结束页码: 946
语种: 英语
英文关键词: air temperature
; morphology
; numerical model
; permafrost
; regional climate
; snow cover
; treeline
; vegetation structure
; British Columbia
; Canada
; Yukon Territory
英文摘要: Air temperature changes were applied to a regional model of permafrost probability under equilibrium conditions for an area of nearly 0.5 × 106 km2 in the southern Yukon and northwestern British Columbia, Canada. Associated environmental changes, including snow cover and vegetation, were not considered in the modelling. Permafrost extent increases from 58% of the area (present day: 1971- 2000) to 76%under a -1 K cooling scenario, whereas warming scenarios decrease the percentage of permafrost area exponentially to 38% (+ 1 K), 24% (+ 2 K), 17% (+ 3 K), 12% (+ 4 K) and 9% (+ 5 K) of the area. The morphology of permafrost gain/loss under these scenarios is controlled by the surface lapse rate (SLR, i.e. air temperature elevation gradient), which varies across the region below treeline. Areas that are maritime exhibit SLRs characteristically similar above and below treeline resulting in low probabilities of permafrost in valley bottoms. When warming scenarios are applied, a loss front moves to upper elevations (simple unidirectional spatial loss). Areas where SLRs are gently negative below treeline and normal above treeline exhibit a loss front moving up-mountain at different rates according to two separate SLRs (complex unidirectional spatial loss). Areas that display high continentally exhibit bidirectional spatial loss in which the loss front moves up-mountain above treeline and down-mountain below treeline. The parts of the region most affected by changes in MAAT (mean annual air temperature) have SLRs close to 0 K km-1 and extensive discontinuous permafrost, whereas the least sensitive in terms of areal loss are sites above the treeline where permafrost presence is strongly elevation dependent. © Author(s) 2013. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/74981
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: Department of Geography, Queen's University, Kingston, Canada; Department of Geography, University of Ottawa, Ottawa, Canada
Recommended Citation:
Bonnaventure P,P,, Lewkowicz A,et al. Impacts of mean annual air temperature change on a regional permafrost probability model for the southern Yukon and northern British Columbia, Canada[J]. Cryosphere,2013-01-01,7(3)