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heimbach |
1.1 |
\begin{abstract} |
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cnh |
1.8 |
This paper describes the MITgcm |
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sea ice model; it presents example Arctic and Antarctic results from a |
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heimbach |
1.10 |
realistic, |
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%eddying, |
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\ml{eddy-permitting,} |
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global ocean and sea ice configuration; |
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cnh |
1.8 |
and it compares B-grid and C-grid dynamic solvers and other |
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numerical details of the parameterized dynamics and thermodynamics in a |
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regional Arctic |
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configuration. |
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Ice mechanics follow a viscous-plastic rheology and the ice momentum |
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mlosch |
1.2 |
equations are solved numerically using either |
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line-successive-over-relaxation (LSOR) or elastic-viscous-plastic |
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(EVP) dynamic models. Ice thermodynamics are represented using either |
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a zero-heat-capacity formulation or a two-layer formulation that |
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mlosch |
1.9 |
conserves enthalpy. The model includes prognostic variables for snow |
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and for sea ice salinity. The above sea ice model components were |
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mlosch |
1.2 |
borrowed from current-generation climate models but they were |
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mlosch |
1.3 |
reformulated on an Arakawa~C grid in order to match the MITgcm oceanic |
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mlosch |
1.2 |
grid and they were modified in many ways to permit efficient and |
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mlosch |
1.9 |
accurate automatic differentiation. % |
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Both stress tensor divergence and advective terms are discretized with |
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the finite-volume method. % |
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cnh |
1.8 |
The choice of the dynamic solver has a considerable |
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mlosch |
1.3 |
effect on the solution; this effect can be larger than, for example, |
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dimitri |
1.4 |
the choice of lateral boundary conditions, of ice rheology, and of |
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mlosch |
1.3 |
ice-ocean stress coupling. The solutions obtained with different |
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mlosch |
1.5 |
dynamic solvers typically differ |
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by 4\,cm\,s$^{-1}$ in ice drift speeds, 1\,m in ice thickness, and |
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dimitri |
1.6 |
order 300\,km$^3$\,yr$^{-1}$ in fresh water (ice and snow) export |
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mlosch |
1.3 |
out of the Arctic. |
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heimbach |
1.1 |
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\end{abstract} |
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mlosch |
1.3 |
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%%% Local Variables: |
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%%% mode: latex |
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%%% TeX-master: "ceaice_part1" |
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%%% End: |