Hydraulic transmissivity inferred from ice-sheet relaxation following Greenland supraglacial lake drainages
Hydraulic transmissivity inferred from ice-sheet relaxation following Greenland supraglacial lake drainages
复制标题
根据格陵兰冰上湖排水后冰盖松弛推断的水力透射率
DOI：
10.1038/s41467-021-24186
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发表时间：
2021
影响因子：
16.6
通讯作者：
& Stone, Howard A.
中科院分区：
文献类型：
--
作者：
Lai, Ching-Yao;Stevens, Laura A;Chase, Danielle L.;Creyts, Timothy T;Behn, Mark D;Das, Sarah B;& Stone, Howard A.
到达格陵兰冰盖底部的表面融水通过排水网络，调节冰盖的流动。在冰盖西部边缘进行的染料和气体示踪研究直接观察到排水效率随季节沿着排水路径演变。然而，在冰厚超过1000米的内陆地区，排水系统的局部演变在很大程度上仍然是未知的。在这里，我们推断排水系统transmittance的基础上，表面隆起松弛快速湖泊排水事件。结合现场观测的五个湖泊排水事件的数学模型和实验室实验，我们表明，表面隆起随时间呈指数下降，在水泡形成的排水湖下的水渗透通过冰下排水系统。这种收缩遵循一个普遍的弛豫规律，其时间尺度揭示了水力transmits，并表明随着融化季节的进展，冰下transmits有两个数量级的增加（从0.8 ± 0.32到215 ± 90.2），这表明季节性融水输入驱动湖泊底部水文发生了显着变化。
Surface meltwater reaching the base of the Greenland Ice Sheet transits through drainage networks, modulating the flow of the ice sheet. Dye and gas-tracing studies conducted in the western margin sector of the ice sheet have directly observed drainage efficiency to evolve seasonally along the drainage pathway. However, the local evolution of drainage systems further inland, where ice thicknesses exceed 1000 m, remains largely unknown. Here, we infer drainage system transmissivity based on surface uplift relaxation following rapid lake drainage events. Combining field observations of five lake drainage events with a mathematical model and laboratory experiments, we show that the surface uplift decreases exponentially with time, as the water in the blister formed beneath the drained lake permeates through the subglacial drainage system. This deflation obeys a universal relaxation law with a timescale that reveals hydraulic transmissivity and indicates a two-order-of-magnitude increase in subglacial transmissivity (from 0.8 ± 0.3to 215 ± 90.2) as the melt season progresses, suggesting significant changes in basal hydrology beneath the lakes driven by seasonal meltwater input.
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勘误表：水文引起的底滑引发的格陵兰冰上湖排水
影响因子：
64.8
作者：
L. Stevens;M. Behn;J. McGuire;Sarah B. Das;I. Joughin;T. Herring;D. Shean;Matt A. King
通讯作者：
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影响因子：
64.8
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影响因子：
3.4
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影响因子：
18.3
作者：
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通讯作者：
Hubbard, A.
影响因子：
18.3
作者：
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通讯作者：
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