On the formulation of sea-ice models. Part 1: Effects of different solver implementations and parameterizations
On the formulation of sea-ice models. Part 1: Effects of different solver implementations and parameterizations
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DOI：
10.1016/j.ocemod.2009.12.008
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发表时间：
2010-01-01
期刊：
影响因子：
3.2
通讯作者：
Hill, Chris
中科院分区：
文献类型：
--
作者：
Losch, Martin;Menemenlis, Dimitris;Hill, Chris
本文介绍了马萨诸塞州理工学院大气环流模式（MITgcm）的海冰分量;它给出了一个真实的、涡流允许的、全球海洋和海冰配置的北极和南极实例结果;它比较了B网格和C网格动态解算器以及一个区域北极配置中参数化动力学和热力学的其他数值细节。冰力学遵循粘塑性流变学，冰动量方程使用线连续超松弛（LSOR）或弹粘塑性（EVP）动力学模型进行数值求解。冰热力学表示使用零热容量配方或两层配方，保持焓。该模型包括雪厚和海冰盐度的预测变量。上述海冰模式组件是从当前一代气候模式中借用的，但为了与MITgcm海洋网格相匹配，它们在荒川C网格上进行了重新表述，并在许多方面进行了修改，以允许有效和准确的自动微分。应力张量散度和平流项均采用有限体积法离散。动态解算器的选择对解有相当大的影响;这种影响可能大于例如横向边界条件、冰流变学和冰-海洋应力耦合的选择。用不同的动态解算器得到的解通常在冰漂移速度上相差几厘米秒（-1），在冰厚度上相差50厘米，在淡水（冰和雪）流出北极方面相差200公里（3）年（-1）。(C)2010爱思唯尔有限公司版权所有。
This paper describes the sea ice component of the Massachusetts Institute of Technology general circulation model (MITgcm); it presents example Arctic and Antarctic results from a realistic, eddy-admitting, global ocean and sea ice configuration; and it compares B-grid anti C-grid dynamic solvers and other numerical details of the parameterized dynamics and thermodynamics in a regional Arctic configuration. Ice mechanics follow a viscous-plastic rheology and the ice momentum equations are solved numerically using either line-successive-over-relaxation (LSOR) or elastic-viscous-plastic (EVP) dynamic models. Ice thermodynamics are represented using either a zero-heat-capacity formulation or a two-layer formulation that conserves enthalpy. The model includes prognostic variables for snow thickness and for sea ice salinity. The above sea ice model components were borrowed from current generation climate models but they were reformulated on an Arakawa C grid in order to match the MITgcm oceanic grid and they were modified in many ways to permit efficient and accurate automatic differentiation. Both stress tensor divergence and advective terms are discretized with the finite-volume method. The choice of the dynamic solver has a considerable effect on the solution; this effect can be larger than, for example, the choice of lateral boundary conditions, of ice rheology, and of ice-ocean stress coupling. The solutions obtained with different dynamic solvers typically differ by a few cm s(-1) in ice drift speeds, 50 cm in ice thickness, and order 200 km(3) yr(-1) in freshwater (ice and snow) export out of the Arctic. (C) 2010 Elsevier Ltd. All rights reserved.