Antarctica contains 90% of the Earth's ice; if it melts, it can significantly contribute to the rise in global sea levels. Over Antarctica, short-term atmospheric warming events have led to significant surface melt in summer. Understanding the conditions of such warming events and subsequent surface melt is highly prioritized in Polar Research. The austral summer of 2016-17 witnessed the largest melt duration of the 21 century over Ingrid Christensen Coast (ICC), East Antarctica. Being situated on the grounded ice near four research stations, understanding the melt over the region has both scientific and operational importance. Here, we investigate the drivers of four major melt events identified over ICC for the austral summer of 2016-17 using the reanalysis dataset, ERA5. The first melt event, coinciding with the season's highest air temperature, was triggered by high turbulent heat flux from strong katabatic winds, while the rest of the events were triggered by low-level, liquid cloud-induced longwave radiation. During the melt events, anomalous high pressure ridges were present over the continent causing low pressure systems to remain stationary for an extended period and direct warm, moist air towards the ICC, facilitating melting. The present study observed melting occurring above the grounding zone, and if such melting extends to a larger scale beyond ice shelves, it could raise significant concerns regarding the hydrodynamics and stability of ice sheets in the future.

中文翻译：

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东南极洲英格丽德·克里斯滕森海岸异常地表融化的驱动因素

南极洲拥有地球上90%的冰；如果它融化，就会极大地导致全球海平面上升。在南极洲，短期的大气变暖事件导致夏季地表显着融化。了解此类变暖事件和随后的地表融化的条件是极地研究的高度优先事项。 2016-17 年夏季，东南极洲英格丽德·克里斯滕森海岸 (ICC) 见证了 21 世纪最大的融化持续时间。位于四个研究站附近的接地冰上，了解该地区的融化具有科学和操作上的重要性。在这里，我们使用再分析数据集 ERA5 调查了 2016-17 年南方夏季 ICC 确定的四次主要融化事件的驱动因素。第一次融化事件与该季节的最高气温同时发生，是由强下降风产生的高湍流热通量引发的，而其余事件则是由低层液云引起的长波辐射引发的。在融化事件期间，大陆上空出现异常高压脊，导致低压系统长时间保持静止，并将温暖潮湿的空气引导至ICC，从而促进融化。目前的研究观察到融化发生在接地区上方，如果这种融化扩大到冰架以外的更大范围，可能会引起人们对未来冰盖的流体动力学和稳定性的严重担忧。