Marsh O J, Arthern R J, De Rydt J
British Antarctic Survey, Cambridge, UK.
Northumbria University, Newcastle, UK.
Nat Commun. 2025 Jul 24;16(1):6697. doi: 10.1038/s41467-025-61796-w.
Tabular iceberg calving reduces ice-shelf extent, affecting ocean circulation and ice-sheet stability. Here we present detailed observations of a rift on the Brunt Ice Shelf, East Antarctica, from 2017-2023 and its behaviour in the lead up to calving in January 2023. The timing of rift propagation was controlled by the rate of change of ocean tide height, wind speed, and an iceberg collision in August 2021, as well as the long-term ice dynamics. A viscoelastic rheological model is used to estimate the relative magnitude of stresses acting on the rift and to determine a critical threshold for fracture, which was exceeded during a sequence of propagation events in early 2019. The eventual calving on 22nd January 2023 occurred at the peak of a spring tide, supporting the conclusion that tides directly influenced the timing.
平板冰山崩解会缩小冰架范围，影响海洋环流和冰盖稳定性。在此，我们展示了2017年至2023年对南极洲东部布朗特冰架上一条裂缝及其在2023年1月崩解前行为的详细观测。裂缝扩展的时间受到海洋潮位变化率、风速、2021年8月的一次冰山碰撞以及长期冰动力学的控制。使用粘弹性流变模型来估计作用在裂缝上的应力的相对大小，并确定断裂的临界阈值，该阈值在2019年初的一系列扩展事件中被超过。最终在2023年1月22日的大潮高峰期发生了崩解，支持了潮汐直接影响时间的结论。
