© 2015 Cambridge University Press. We study a simplified model of ice-ocean interaction beneath a floating ice shelf, and investigate the possibility for channels to form in the ice shelf base due to spatial variations in conditions at the grounding line. The model combines an extensional thin-film description of viscous ice flow in the shelf, with melting at its base driven by a turbulent ocean plume. Small transverse perturbations to the one-dimensional steady state are considered, driven either by ice thickness or subglacial discharge variations across the grounding line. Either forcing leads to the growth of channels downstream, with melting driven by locally enhanced ocean velocities, and thus heat transfer. Narrow channels are smoothed out due to turbulent mixing in the ocean plume, leading to a preferred wavelength for channel growth. In the absence of perturbations at the grounding line, linear stability analysis suggests that the one-dimensional state is stable to initial perturbations, chiefly due to the background ice advection.
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledged KAUST grant number(s): KUK-C1-013-04
Acknowledgements: This publication arises from research funded in part by Award No KUK-C1-013-04,made by King Abdullah University of Science and Technology (KAUST), andin part by the John Fell Oxford University Press (OUP) Research Fund. M.C.D.acknowledges further support from the Engineering and Physical Sciences ResearchCouncil (EPSRC) of the UK through grant no. EP/K008595/1. A.J.W. acknowledgesfinancial support through the research program of the European Union FP7 awardPCIG13-GA-2013-618610 SEAICE-CFD. I.J.H. was supported by a Marie Curie FP7Integration Grant within the 7th European Union Framework Programme. The authorsare indebted to the three anonymous referees whose comments significantly improvedthe final paper.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.