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Enhanced ablation of a vertical ice wall due to an external freshwater plume

Published online by Cambridge University Press:  28 November 2016

Craig D. McConnochie Open the ORCID record for Craig D. McConnochie [Opens in a new window]  and
Ross C. Kerr
Craig D. McConnochie*
Affiliation:
Research School of Earth Sciences, The Australian National University, Canberra, ACT 2601, Australia
Ross C. Kerr
Affiliation:
Research School of Earth Sciences, The Australian National University, Canberra, ACT 2601, Australia
*
†Email address for correspondence: [email protected]
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Abstract

We investigate the effect of an external freshwater plume on the dissolution of a vertical ice wall in salty water using laboratory experiments. We measure the plume velocity, the ablation velocity of the ice and the temperature at the ice wall. The freshwater volume flux, $Q_{s}$, is varied between experiments to determine where the resultant wall plume transitions from being dominated by the distributed buoyancy flux due to dissolution of the ice, to being dominated by the initial buoyancy flux, $B_{s}$. We find that when $B_{s}$ is significantly larger than the distributed buoyancy flux from dissolution, the plume velocity is uniform with height and is proportional to $B_{s}^{1/3}$, the interface temperature is independent of $B_{s}$, and the ablation velocity increases with $B_{s}$.

JFM classification

Geophysical and Geological Flows: Ice sheets Convection: Plumes/thermals Phase change: Solidification/melting
Type
Papers
Information
Journal of Fluid Mechanics , Volume 810 , 10 January 2017 , pp. 429 - 447
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Copyright
© 2016 Cambridge University Press 

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