Numerical experiments on Arctic sea ice were carried out using an ice-ocean coupled model developed by the Massachusetts Institute of Technology (MITgcm). Special attention was paid to the effects of using two types of sea ice rheology, i.e. viscous-plastic rheology and elastic-viscous-plastic rheology. The results indicated that the major distribution patterns of internal stress components σ11 and σ22 are similar using the two ice rheology schemes. In winter, areas with comparatively large internal stress components are mostly near land north of the Canadian Arctic Archipelago, Greenland and east of Greenland. In summer, however, areas with comparatively large internal stress components are mostly north of the Canadian Arctic Archipelago and Greenland. The internal stress components σ12 vary greatly in these experiments, contributing to apparent differences in the force of sea-ice interaction. The difference vector in sea-ice interaction force contributing has anticlockwise and clockwise features in the Beaufort Sea and the inner part of the Arctic Ocean respectively, leading to similar patterns in differences in sea-ice drift in these two regions. Comparing with observations, it is seen that the EVP rheology is more appropriate for simulation of Beaufort Gyre.%利用美国麻省理工学院开发的数值模式MITgcm设计了区域冰·洋耦合数值模拟试验,开展了海冰动力学过程中两种流变学方案(黏性-塑性流变学和弹性-黏性-塑性流变学)的对比研究.结果表明,两种方案模拟的海冰内部应力张量分量σ<,11>和σ<,22>总体分布形式相近.冬季,大值区主要位于加拿大北极群岛和格陵兰岛北侧以及格陵兰岛东侧靠近陆地海区.夏季,大值区主要位于加拿大北极群岛和格陵兰岛北侧.但σ<,12>差别较大,可造成海冰相互作用力的明显差异.海冰相互作用力差值矢量在波弗特海区域呈逆时针涡旋分布而在北冰洋内部呈围绕北极点的顺时针涡旋分布,这导致海冰流速差异也出现相似的特点.相比较而言,弹性-黏性-塑性流变学方案对波弗特涡模拟得更好一些.
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