DOI: 10.1029/2018JF004669
Scopus记录号: 2-s2.0-85052512856
论文题名: A Model for the Downstream Evolution of Temperate Ice and Subglacial Hydrology Along Ice Stream Shear Margins
作者: Meyer C.R. ; Yehya A. ; Minchew B. ; Rice J.R.
刊名: Journal of Geophysical Research: Earth Surface
ISSN: 21699003
出版年: 2018
卷: 123, 期: 8 起始页码: 1682
结束页码: 1698
语种: 英语
英文关键词: numerical models
; shear margins
; subglacial hydrology
; temperate ice
英文摘要: Antarctic mass balance and contribution to sea level rise are dominated by the flow of ice through narrow conduits called ice streams. These regions of relatively fast flow drain over 90% of the ice sheet and generate significant amounts of frictional heat at the ice stream margins where there is a transition to slow flow in the ridge. This heat can generate temperate ice and a sharp transition in flow speed between the stream and the ridge. Within zones of temperate ice, meltwater is produced and drains to the bed. Here we model the downstream development of a temperate zone along an ice stream shear margin and the flow of meltwater through temperate ice into a subglacial hydrologic system. The hydrology sets the basal effective pressure, defined as the difference between ice overburden and water pressure. Using the southern shear margin of Bindschadler Ice Stream as a case study, our model results indicate an abrupt transition from a distributed to channelized hydrologic system within a few ice thicknesses of the point where the temperate zone initiates. This transition leads to a strengthening of the till due to reduced pore pressure because the water pressure in the channel is lower than in the distributed system, a potential mechanism by which hydrology can prevent lateral migration of shear margins. ©2018. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/113309
Appears in Collections: 气候减缓与适应
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作者单位: Department of Earth Sciences, University of Oregon, Eugene, OR, United States; John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, United States; Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, United States; Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA, United States
Recommended Citation:
Meyer C.R.,Yehya A.,Minchew B.,et al. A Model for the Downstream Evolution of Temperate Ice and Subglacial Hydrology Along Ice Stream Shear Margins[J]. Journal of Geophysical Research: Earth Surface,2018-01-01,123(8)