Greenland ice sheet motion coupled with daily melting in late summer
Greenland ice sheet motion coupled with daily melting in late summer
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DOI：
10.1029/2008gl035758
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发表时间：
2009-01
影响因子：
5.2
通讯作者：
A. Shepherd;A. Hubbard;P. Nienow;Matt A. King;M. McMillan;I. Joughin
中科院分区：
文献类型：
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作者：
A. Shepherd;A. Hubbard;P. Nienow;Matt A. King;M. McMillan;I. Joughin
我们使用地面和卫星观测来检测夏末格陵兰冰盖（GrIS）流量的大昼夜和较长周期变化，这些变化与其表面水文变化密切相关。昼夜信号与表面融化的周期性变化有关，而较长周期的信号与冰上湖泊的间歇性排水有关。冰的速度增加一倍，约2小时后，每天融化的高峰期，大约返回到冬季水平后12小时左右，表明地表和基础水文之间的密切联系。在夏末，冰盖每融化一个正度日就会加速35%。所观察到的表面融化和增强流量之间的联系是典型的阿尔卑斯山冰川，这可能提供了一个适当的模拟在气候变暖的GrIS的演变。
We use ground‐based and satellite observations to detect large diurnal and longer‐period variations in the flow of the Greenland Ice Sheet (GrIS) during late summer that are strongly coupled with changes in its surface hydrology. The diurnal signals are associated with periodic changes in surface melting, and the longer‐period signals are associated with the episodic drainage of supra‐glacial lakes. Ice velocity doubles around 2 hours after peak daily melting and returns approximately to wintertime levels around 12 hours afterwards, demonstrating an intimate link between the surface and basal hydrology. During late summer, the ice sheet accelerates by 35% per positive degree‐day of melting. The observed link between surface melting and enhanced flow is typical of Alpine glaciers, which may provide an appropriate analogue for the evolution of the GrIS in a warming climate.