Understanding the causes of recent catastrophic ice shelf disintegrations is a crucial step towards improving coupled models of the Antarctic Ice Sheet and predicting its future state and contribution to sea-level rise. An overlooked climate-related causal factor is regional sea ice loss. Here we show that for the disintegration events observed (the collapse of the Larsen A and B and Wilkins ice shelves), the increased seasonal absence of a protective sea ice buffer enabled increased flexure of vulnerable outer ice shelf margins by ocean swells that probably weakened them to the point of calving. This outer-margin calving triggered wider-scale disintegration of ice shelves compromised by multiple factors in preceding years, with key prerequisites being extensive flooding and outer-margin fracturing. Wave-induced flexure is particularly effective in outermost ice shelf regions thinned by bottom crevassing. Our analysis of satellite and ocean-wave data and modelling of combined ice shelf, sea ice and wave properties highlights the need for ice sheet models to account for sea ice and ocean waves.Less sea ice allowed ocean swells to flex weakened ice shelves in Antarctica, contributing to their collapse.

中文翻译：

---

海冰流失和海浪引发南极冰架解体

了解最近灾难性冰架解体的原因是改进南极冰盖耦合模型和预测其未来状态和对海平面上升的贡献的关键一步。一个被忽视的与气候相关的因果因素是区域海冰损失。在这里，我们表明，对于观察到的解体事件（拉森 A 和 B 以及威尔金斯冰架的坍塌），保护性海冰缓冲区的季节性缺失使易受伤害的外冰架边缘的弯曲增加，这可能会削弱它们到产犊的地步。前几年受多种因素影响，这种外缘崩解引发了更大规模的冰架解体，关键先决条件是大面积洪水和外缘破裂。波浪引起的弯曲在因底部开裂而变薄的最外层冰架区域特别有效。我们对卫星和海浪数据的分析以及对冰架、海冰和波浪特性组合的建模突出表明需要冰盖模型来解释海冰和海浪。 减少海冰使海洋膨胀使南极洲削弱的冰架弯曲，导致他们的崩溃。