On the formulation of snow thermal conductivity in large-scale sea ice models

Lecomte, O.; Fichefet, T.; Vancoppenolle, M.; Domine, F.; Massonnet, F.; Mathiot, P.; Morin, S.; Barriat, P.Y.. 2013 On the formulation of snow thermal conductivity in large-scale sea ice models. Journal of Advances in Modeling Earth Systems, 5 (3). 542-557. 10.1002/jame.20039

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Abstract/Summary

An assessment of the performance of a state-of-the-art large-scale coupled sea ice - ocean model, including a new snow multilayer thermodynamic scheme, is performed. Four 29-years-long simulations are compared against each other and against sea ice thickness and extent observations. Each simulation uses a separate parameterization for snow thermo-physical properties. The first simulation uses a constant thermal conductivity and prescribed density profiles. The second and third parameterizations use typical power-law relationships linking thermal conductivity directly to density (prescribed as in the first simulation). The fourth parameterization is newly developed and consists of a set of two linear equations relating the snow thermal conductivity and density to the mean seasonal wind speed. Results show that simulation 1 leads to a significant overestimation of the sea ice thickness due to overestimated thermal conductivity, particularly in the Northern Hemisphere. Parameterizations 2 and 4 lead to a realistic simulation of the Arctic sea ice mean state. Simulation 3 results in the underestimation of the sea ice basal growth in both hemispheres, but is partly compensated by lateral growth and snow ice formation in the Southern Hemisphere. Finally, parameterization 4 improves the simulated snow depth distributions by including snow packing by wind, and shows potential for being used in future works. The intercomparison of all simulations suggests that the sea ice model is more sensitive to the snow representation in the Arctic than it is in the Southern Ocean, where the sea ice thickness is not driven by temperature profiles in the snow.

Item Type:	Publication - Article
Digital Object Identifier (DOI):	10.1002/jame.20039
Programmes:	BAS Programmes > Polar Science for Planet Earth (2009 - ) > Polar Oceans
ISSN:	19422466
Additional Keywords:	sea ice, snow, model, thermodynamics, mass balance
Date made live:	11 Jul 2013 08:13 +0 (UTC)
URI:	https://nora.nerc.ac.uk/id/eprint/502595

Item Type:

Publication - Article

Digital Object Identifier (DOI):

10.1002/jame.20039

Programmes:

BAS Programmes > Polar Science for Planet Earth (2009 - ) > Polar Oceans

ISSN:

19422466

Additional Keywords:

sea ice, snow, model, thermodynamics, mass balance

Date made live:

11 Jul 2013 08:13 +0 (UTC)