The rapid drainage of supraglacial lakes injects substantial volumes of water to the bed of the Greenland ice sheet over short timescales. The effect of these water pulses on the development of basal hydrological systems is largely unknown. To address this, we develop a lake drainage model incorporating both (1) a subglacial radial flux element driven by elastic hydraulic jacking and (2) downstream drainage through a linked channelized and distributed system. Here we present the model and examine whether substantial, efficient subglacial channels can form during or following lake drainage events and their effect on the water pressure in the surrounding distributed system. We force the model with field data from a lake drainage site, 70 km from the terminus of Russell Glacier in West Greenland. The model outputs suggest that efficient subglacial channels do not readily form in the vicinity of the lake during rapid drainage and instead water is evacuated primarily by a transient turbulent sheet and the distributed system. Following lake drainage, channels grow but are not large enough to reduce the water pressure in the surrounding distributed system, unless preexisting channels are present throughout the domain. Our results have implications for the analysis of subglacial hydrological systems in regions where rapid lake drainage provides the primary mechanism for surface-to-bed connections. KEY POINTS Model for subglacial hydrological analysis of rapid lake drainage eventsLimited subglacial channel growth during and following rapid lake drainagePersistence of distributed drainage in inland areas where channel growth is limited.

中文翻译：

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冰川湖上快速排水后的冰河下水文发展模拟。

冰川湖的快速排水在短时间内向格陵兰冰盖的河床注入了大量的水。这些水脉冲对基础水文系统发展的影响在很大程度上是未知的。为了解决这个问题，我们开发了一个湖泊排水模型，该模型结合了（1）由弹性液压顶进驱动的冰川下径向通量元素和（2）通过链接的通道化和分布式系统进行的下游排水。在这里，我们介绍该模型并检查在湖泊排水事件期间或之后是否会形成大量有效的冰川下通道，以及它们对周围分布式系统中水压的影响。我们使用来自西格陵兰罗素冰川终点站70公里的湖泊排水点的现场数据来强制模型。模型输出表明，在快速排水期间，湖附近不易形成有效的冰河下渠道，取而代之的是主要通过瞬态湍流片和分布式系统将水排空。湖泊排水后，除非整个区域内都存在预先存在的通道，否则通道会增长，但其大小不足以降低周围分布式系统中的水压。我们的研究结果对快速湖泊排水为地表-河床联系提供主要机制的地区冰下水文系统的分析具有重要意义。湖泊快速排水事件的冰河下水文分析的要点模型湖泊快速排水期间和之后有限的冰川下河道增长在河道增长受限的内陆地区持续存在分布式排水。