Enhancement factors for grounded ice and ice shelves inferred from an anisotropic ice-flow model

被引：81

作者：

Ma, Ying ^{[1
]}

Gagliardini, Olivier ^{[1
]}

Ritz, Catherine ^{[1
]}

Gillet-Chaulet, Fabien ^{[2
]}

Durand, Gael ^{[1
]}

Montagnat, Maurine ^{[1
]}

机构：

[1] Univ Grenoble 1, CNRS, Lab Glaciol & Geophys Environm, F-38402 St Martin Dheres, France

[2] British Antarctic Survey, NERC, Cambridge CB3 0ET, England

来源：

JOURNAL OF GLACIOLOGY | 2010年 / 56卷 / 199期

关键词：

CENTRAL GREENLAND; EAST ANTARCTICA; SHEET FLOW; POLAR ICE; CORE; DIVIDE;

D O I：

10.3189/002214310794457209

中图分类号：

P9 [自然地理学];

学科分类号：

0705 ; 070501 ;

摘要：

Polar ice is known to be one of the most anisotropic natural materials. For a given fabric the polycrystal viscous response is strongly dependent on the actual state of stress and strain rate. Within an ice sheet, grounded-ice parts and ice shelves have completely different stress regimes, so one should expect completely different impacts of ice anisotropy on the flow. The aim of this work is to quantify, through the concept of enhancement factors, the influence of ice anisotropy on the flow of grounded ice and ice shelves. For this purpose, a full-Stokes anisotropic marine ice-sheet flowline model is used to compare isotropic and anisotropic diagnostic velocity fields on a fixed geometry. From these full-Stokes results, we propose a definition of enhancement factors for grounded ice and ice shelves, coherent with the asymptotic models used for these regions. We then estimate realistic values for the enhancement factors induced by ice anisotropy for grounded ice and ice shelves.

引用

页码：805 / 812

页数：8

共 31 条

[1]

[Anonymous], 1984, J APPL MECH, DOI DOI 10.1115/1.3167761

[2] Shallow shelf approximation as a "sliding law'' in a thermomechanically coupled ice sheet model [J].

Bueler, Ed ;

Brown, Jed .

JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE, 2009, 114

[3] Viscoplastic modeling of texture development in polycrystalline ice with a self-consistent approach: Comparison with bound estimates [J].

Castelnau, O ;

Duval, P ;

Lebensohn, RA ;

Canova, GR .

JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH, 1996, 101 (B6) :13851-13868

[4] Anisotropic behavior of GRIP ices and flow in Central Greenland [J].

Castelnau, O ;

Shoji, H ;

Mangeney, A ;

Milsch, H ;

Duval, P ;

Miyamoto, A ;

Kawada, K ;

Watanabe, O .

EARTH AND PLANETARY SCIENCE LETTERS, 1998, 154 (1-4) :307-322

[5] Borehole imagery of meteoric and marine ice layers in the Amery Ice Shelf, East Antarctica [J].

Craven, M ;

Carsey, F ;

Behar, A ;

Matthews, J ;

Brand, R ;

Elcheikh, A ;

Hall, S ;

Treverrow, A .

JOURNAL OF GLACIOLOGY, 2005, 51 (172) :75-84

[6] Properties of a marine ice layer under the Amery Ice Shelf, East Antarctica [J].

Craven, Mike ;

Allison, Ian ;

Fricker, Helen Amanda ;

Warner, Roland .

JOURNAL OF GLACIOLOGY, 2009, 55 (192) :717-728

[7] Change in ice rheology during climate variations - implications for ice flow modelling and dating of the EPICA Dome C core [J].

Durand, G. ;

Gillet-Chaulet, F. ;

Svensson, A. ;

Gagliardini, O. ;

Kipfstuhl, S. ;

Meyssonnier, J. ;

Parrenin, F. ;

Duval, P. ;

Dahl-Jensen, D. .

CLIMATE OF THE PAST, 2007, 3 (01) :155-167

[8] Marine ice sheet dynamics: Hysteresis and neutral equilibrium [J].

Durand, G. ;

Gagliardini, O. ;

de Fleurian, B. ;

Zwinger, T. ;

Le Meur, E. .

JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE, 2009, 114

[9]

DURAND G, 2009, PHYS ICE CORE RECORD, V2, P91

[10]

Eisen O, 2007, CRYOSPHERE, V1, P1

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