DOI: 10.5194/tc-14-1273-2020
论文题名: The influence of water percolation through crevasses on the thermal regime of a Himalayan mountain glacier
作者: Gilbert A. ; Sinisalo A. ; R. Gurung T. ; Fujita K. ; B. Maharjan S. ; C. Sherpa T. ; Fukuda T.
刊名: Cryosphere
ISSN: 19940416
出版年: 2020
卷: 14, 期: 4 起始页码: 1273
结束页码: 1288
语种: 英语
英文关键词: atmospheric modeling
; energy conservation
; glacier
; ground penetrating radar
; percolation
; thermal regime
; timescale
; warming
; Himalayas
; India
; Jammu and Kashmir
; Nepal
; Samba
英文摘要: In cold and arid climates, small glaciers with cold accumulation zones are often thought to be entirely cold based. However, scattering in ground-penetrating radar (GPR) measurements on the Rikha Samba Glacier in the Nepal Himalayas suggests a large amount of temperate ice that seems to be influenced by the presence of crevassed areas. We used a coupled thermo-mechanical model forced by a firn model accounting for firn heating to interpret the observed thermal regime. Using a simple energy conservation approach, we show that the addition of water percolation and refreezing in crevassed areas explains these observations. Model experiments show that both steady and transient thermal regimes are significantly affected by latent heat release in crevassed areas. This makes half of the glacier base temperate, resulting in an ice dynamic mainly controlled by basal friction instead of ice deformation. The timescale of thermal regime change, in response to atmospheric warming, is also greatly diminished, with a potential switch from cold to temperate basal ice in 50-60 years in the upper part of the glacier instead of the 100-150 years that it would take without the effect of the crevasses. This study highlights the crucial role of water percolation through the crevasses on the thermal regime of glaciers and validates a simple method to account for it in glacier thermo-mechanical models. © 2020 Copernicus GmbH. All rights reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/164461
Appears in Collections: 气候变化与战略
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作者单位: Department of Geosciences, University of Oslo, Oslo, Norway; International Centre for Integrated Mountain Development, P.O. Box 3226, Kathmandu, Nepal; Graduate School of Environmental Studies, Nagoya University, Nagoya, 464-8601, Japan; Graduate School of Environmental Science, Hokkaido University, Sapporo, 060-0810, Japan; Institute of Low Temperature Science, Hokkaido University, Sapporo, 060-0819, Japan; GRID, Arendal, Norway; Hokkaido Government, Sapporo, 060-8588, Japan
Recommended Citation:
Gilbert A.,Sinisalo A.,R. Gurung T.,et al. The influence of water percolation through crevasses on the thermal regime of a Himalayan mountain glacier[J]. Cryosphere,2020-01-01,14(4)