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标题：Interaction between ice sheet dynamics and subglacial lake circulation: a coupled modelling approach
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作者：M. Thoma ; K. Grosfeld ; C. Mayer 等
期刊名称：The Cryosphere
印刷版ISSN：1994-0416
电子版ISSN：1994-0424
出版年度：2010
卷号：04
期号：01
页码：1-12
出版社：Copernicus Publications
摘要：Subglacial lakes in Antarctica influence to a large extent the flow of the ice sheet. In this study we use an idealised lake geometry to study this impact. We employ a) an improved three-dimensional full-Stokes ice flow model with a nonlinear rheology, b) a three-dimensional fluid dynamics model with eddy diffusion to simulate the basal mass balance at the lake-ice interface, and c) a newly developed coupler to exchange boundary conditions between the two individual models. Different boundary conditions are applied over grounded ice and floating ice. This results in significantly increased temperatures within the ice on top of the lake, compared to ice at the same depth outside the lake area. Basal melting of the ice sheet increases this lateral temperature gradient. Upstream the ice flow converges towards the lake and accelerates by about 10% whenever basal melting at the ice-lake boundary is present. Above and downstream of the lake, where the ice flow diverges, a velocity decrease of about 10% is simulated.