A wave-based model for the marginal ice zone including a floe breaking parameterization
A wave-based model for the marginal ice zone including a floe breaking parameterization
复制标题
DOI：
10.1029/2010jc006682
复制
发表时间：
2011-04-01
影响因子：
3.6
通讯作者：
Bertino, L.
中科院分区：
文献类型：
--
作者：
Dumont, D.;Kohout, A.;Bertino, L.
边缘冰带（MIZ）是开放海洋和冰覆盖海洋之间的边界，在那里海冰受到海浪冲击的显著影响。波浪对浮冰的破裂负有责任，并决定了MIZ的范围和浮冰的大小分布。当冰盖高度破碎时，其行为在性质上与具有大浮冰的浮冰不同。因此，将波浪-冰相互作用纳入海冰-海洋模型是非常重要的。为了实现这一目标，考虑了两种影响：海冰作为波浪能量的阻尼器的作用和波浪引起的浮冰破碎。这两个过程共同作用，改变入射波谱，并决定了MIZ的主要特性。通过考虑冰作为柔性材料和刚性材料，并使用当前冰临界弯曲应变和强度的估计，推导了一个简单而新颖的浮冰破碎参数化。将该参数化方法与一维数值框架下的波散射模型相结合，评价了流体粒径分布和MIZ范围。该模型预测了破碎的海冰和中央冰盖之间的急剧过渡，从而为MIZ提供了一个自然的定义。在实际的初始条件和边界条件下，找到了MIZ范围的合理值。数值设置与典型的冰-海洋模式相当，并考虑到未来在二维海冰模式中的实现。
The marginal ice zone (MIZ) is the boundary between the open ocean and ice-covered seas, where sea ice is significantly affected by the onslaught of ocean waves. Waves are responsible for the breakup of ice floes and determine the extent of the MIZ and floe size distribution. When the ice cover is highly fragmented, its behavior is qualitatively different from that of pack ice with large floes. Therefore, it is important to incorporate wave-ice interactions into sea ice-ocean models. In order to achieve this goal, two effects are considered: the role of sea ice as a dampener of wave energy and the wave-induced breakup of ice floes. These two processes act in concert to modify the incident wave spectrum and determine the main properties of the MIZ. A simple but novel parameterization for floe breaking is derived by considering alternatively ice as a flexible and rigid material and by using current estimates of ice critical flexural strain and strength. This parameterization is combined with a wave scattering model in a one-dimensional numerical framework to evaluate the floe size distribution and the extent of the MIZ. The model predicts a sharp transition between fragmented sea ice and the central pack, thus providing a natural definition for the MIZ. Reasonable values are found for the extent of the MIZ given realistic initial and boundary conditions. The numerical setting is commensurate with typical ice-ocean models, with the future implementation into two-dimensional sea ice models in mind.