Wave-ice breakup model for inclusion in CICE

A numerical model of ocean wave interactions with Antarctic sea ice cover, including: (i) attenuation of wave energy due to the ice cover (based on the empirical model of Meylan, Bennetts, Kohout, 2014, Geophys Res Lett, doi:10.1002/2014GL060809); and (ii) breakup of the ice cover into smaller floes due to strains imposed by wave motion (based on the theory of Williams et al, 2013, Ocean Model., doi:10.1016/j.ocemod.2013.05.010). The model is coded in FORTRAN90 for use as a module in a standalone version of the CICEv4.1 sea ice model (http://oceans11.lanl.gov/trac/CICE). It requires incident wave forcing to be specified at some constant latitude outside the ice cover, which can be user chosen or imported from data files (e.g. data given by Wavewatch III hindcasts, see http://doi.org/10.4225/08/523168703DCC5). Modifications to the existing CICE routines are given to allow integration of the broken floe sizes into its lateral melting scheme, and for incorporation of a floe bonding scheme. Bennetts, O'Farrell and Uotila (submitted) use the model to study the impact of wave-induced ice breakup on model predictions of the concentration and volume of Antarctic sea ice.南极海冰覆盖与海浪相互作用数值模型，包含以下内容： (i) 海冰覆盖引发的海浪能量衰减（基于Meylan、Bennetts与Kohout于2014年发表于《地球物理研究快报》（Geophys Res Lett）的经验模型，DOI:10.1002/2014GL060809）； (ii) 海浪运动产生的应力引发海冰破碎为更小浮冰的过程（基于Williams等人2013年发表于《海洋模拟》（Ocean Model.）的理论，DOI:10.1016/j.ocemod.2013.05.010）。 本模型以FORTRAN90语言编写，可作为模块集成至独立版本的CICEv4.1海冰模型中（访问地址：http://oceans11.lanl.gov/trac/CICE）。该模型需在海冰覆盖区外的固定纬度处指定入射海浪强迫场，该强迫场可由用户自行设定，或从数据文件中导入（例如由Wavewatch III再分析预报提供的数据，详见http://doi.org/10.4225/08/523168703DCC5）。 本文提供了对现有CICE程序的修改方案，可将破碎浮冰尺寸集成至其侧向融冰模块中，并支持浮冰黏结方案的接入。 Bennetts、O'Farrell与Uotila（已投稿）利用该模型研究了海浪诱导海冰破碎对南极海冰浓度与体积模拟结果的影响。