Negribreen, a tidewater glacier located in central eastern Svalbard, began actively surging after it experienced an initial collapse in summer 2016. The surge resulted in horizontal surface velocities of more than 25 m d−1, making it one of the fastest-flowing glaciers in the archipelago. The last surge of Negribreen likely occurred in the 1930s, but due to a long quiescent phase, investigations of this glacier have been limited. As Negribreen is part of the Negribreen Glacier System, one of the largest glacier systems in Svalbard, investigating its current surge event provides important information on surge behaviour among tidewater glaciers within the region. Here, we demonstrate the surge development and discuss triggering mechanisms using time series of digital elevation models (1969–2018), surface velocities (1995–2018), crevasse patterns and glacier extents from various data sources. We find that the active surge results from a four-stage process. Stage 1 (quiescent phase) involves a long-term, gradual geometry change due to high subglacial friction towards the terminus. These changes allow the onset of Stage 2, an accelerating frontal destabilization, which ultimately results in the collapse (Stage 3) and active surge (Stage 4).

中文翻译：

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从高摩擦区到正面坍塌：正在进行的潮水冰川涌动的动力学，内格里布林，斯瓦尔巴

Negribreen 是位于斯瓦尔巴群岛中东部的潮水冰川，在 2016 年夏季经历了最初的崩塌后开始积极涌动。涌动导致水平表面速度超过 25 md-1，使其成为群岛中流动最快的冰川之一。内格里布林的最后一次激增可能发生在 1930 年代，但由于长期处于静止阶段，对该冰川的研究受到限制。由于内格里布林是内格里布林冰川系统的一部分，内格里布林冰川系统是斯瓦尔巴群岛最大的冰川系统之一，调查其当前的涌浪事件可以提供有关该地区潮水冰川涌流行为的重要信息。在这里，我们使用来自各种数据源的数字高程模型（1969-2018）、地表速度（1995-2018）、裂缝模式和冰川范围的时间序列来展示浪涌发展并讨论触发机制。我们发现主动浪涌是由四个阶段的过程产生的。第 1 阶段（静止阶段）涉及长期、由于对终点的高冰下摩擦，几何形状逐渐变化。这些变化允许第 2 阶段的开始，即加速的正面不稳定，最终导致崩溃（第 3 阶段）和活跃的浪涌（第 4 阶段）。