Imperial College London
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ProfessorMartinSiegert

Faculty of Natural Sciences, The Grantham Institute for Climate Change

Visiting Professor
 
 
 
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Contact

 

+44 (0)20 7594 9666m.siegert Website

 
 
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Assistant

 

Ms Gosia Gayer +44 (0)20 7594 9666

 
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Location

 

Grantham Directors OfficeSherfield BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Scott:2022:10.5194/egusphere-egu22-6500,
author = {Scott, W and Kramer, S and Yeager, B and Holland, P and Nicholls, KW and Siegert, M and Piggott, M},
doi = {10.5194/egusphere-egu22-6500},
title = {First steps for a 3d flexible, unstructured finite element ocean model for flow under ice shelf cavities: an ISOMIP+ case study},
url = {http://dx.doi.org/10.5194/egusphere-egu22-6500},
year = {2022}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - <jats:p>&lt;p&gt;Accurate modelling of basal melting beneath ice shelves is key to reducing the uncertainty in forecasts of ice-shelf stability and, thus, the Antarctic contribution to sea level rise. However, the lack of flexibility inherent to traditional ocean models can pose problems.&lt;em&gt; &lt;/em&gt;&lt;/p&gt;&lt;p&gt;Obtaining accurate melt estimates requires capturing the turbulent exchange of momentum, heat and salt at the ice-ocean interface, which may be modulated by the competing effects of stratification and basal slope. There are still significant uncertainties surrounding the trade-off between the simplicity of the melt parameterisation and the processes that need to be resolved by the numerical ocean model near the boundary.&lt;/p&gt;&lt;p&gt;Real ice-shelf cavity geometries are complicated. Bathymetric valleys are common and provide pathways for warm circumpolar deep water. The ice base is marked by channels, crevasses and terraces. These features will affect the boundary flow, with an added complication that melting plays a role in their formation. It is very difficult to model such flow regimes using a traditional ocean model not only because of the resolution constraints imposed by inflexible grids, but also due to the inbuilt assumptions of large aspect ratio processes and domains that may be violated when flow occurs past these features.&lt;/p&gt;&lt;p&gt;Ice flow models are very sensitive to how they are forced by melting at the grounding line, where the ice starts to float. The grounding line is precisely the region where ocean models are most questionable due to insufficient resolution imposed by limitations on the grid. Subglacial outflow into the cavity will likely break the inherent physical assumptions of hydrostatic, non-negligible vertical accelerations in large aspect ratio domains.&
AU  - Scott,W
AU  - Kramer,S
AU  - Yeager,B
AU  - Holland,P
AU  - Nicholls,KW
AU  - Siegert,M
AU  - Piggott,M
DO  - 10.5194/egusphere-egu22-6500
PY  - 2022///
TI  - First steps for a 3d flexible, unstructured finite element ocean model for flow under ice shelf cavities: an ISOMIP+ case study
UR  - http://dx.doi.org/10.5194/egusphere-egu22-6500
ER  -
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