Model of iceberg drift and decay including breakup

Because of difficulties in adequately simulating their breakup, large Antarctic icebergs to date have either not been represented in models or represented but with no breakup scheme such that they consistently survive too long and travel too far compared with observations. Here, we introduce a representation of iceberg fracturing using a breakup scheme based on the “footloose mechanism.” We optimize the parameters of this breakup scheme by forcing the iceberg model with an ocean state estimate and comparing the modeled iceberg trajectories and areas with the Antarctic Iceberg Tracking Database. We show that including large icebergs and a representation of their breakup substantially affects the iceberg meltwater distribution, with implications for the circulation and stratification of the Southern Ocean. This data link includes the model developed for the study, including a link to the forcing fields needed to replicate the model results.

鉴于难以精准模拟大型南极冰山的崩解过程，当前相关数值模型要么未纳入此类冰山，要么虽纳入却未设置崩解方案，致使其存活时长与漂移距离均持续远超观测结果。为此，我们提出了一种基于“自由漂浮机制（footloose mechanism）”的崩解方案，用以实现冰山断裂过程的模拟表征。我们通过将冰山模型与海洋状态估计结果进行强迫驱动，并将模拟得到的冰山轨迹与面积数据与“南极冰山追踪数据库（Antarctic Iceberg Tracking Database）”进行比对，对该崩解方案的参数完成了优化。研究结果表明，纳入大型冰山及其崩解过程的模拟，会显著改变冰山融水的分布格局，进而对南大洋的环流与层结产生重要影响。本数据集包含本研究开发的模型，并提供了复现该模型结果所需的强迫场数据链接。