Freshwater flux to Sermilik Fjord, SE Greenland
Freshwater flux to Sermilik Fjord, SE Greenland
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流入格陵兰东南部塞尔米利克峡湾的淡水通量
DOI：
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
D. As
中科院分区：
文献类型：
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作者：
S. Mernild;I. Howat;Y. Ahn;G. Liston;K. Steffen;B. H. Jakobsen;B. Hasholt;B. Fog;D. As
抽象的。陆地输入的淡水通量塞尔米利克峡湾，格陵兰东南部，估计，表明冰排放的淡水的主要来源。1999-2008年的淡水通量为40.4 ± 4.9×109 m3 y−1，其中85%来自冰川排泄（65%来自黑尔海姆冰川），11%来自地表径流（来自融水和雨水），3%来自峡湾表面的降水，1%来自冰下地热和基底冰运动引起的摩擦融化。结果表明，冰排放的主导地位，作为一个主要的机制，提供淡水塞尔米利克峡湾。从卫星获得的平均表面速度，冰川宽度和估计的冰厚度，并在陆地表面淡水径流的波动进行了模拟的基础上观测到的气象数据的冰流量的时间序列计算的Helheim冰川，Midgard冰川和Fenris冰川。这些模拟进行了比较，并对独立的冰川流域径流观测偏差校正。Sermilik峡湾的模拟径流量是可变的，从1999年的2.9 ± 0.4×109 m3 y−1到2005年的5.9 ± 0.9×109 m3 y−1。Helheim冰川区的子流域径流量占Sermilik峡湾总径流量的25%。从不同的子集水区的径流分布建议冰川覆盖的空间变化的强烈影响，表明高径流量，冰川覆盖存在于低海拔。
Abstract. Terrestrial inputs of freshwater flux to Sermilik Fjord, SE Greenland, were estimated, indicating ice discharge to be the dominant source of freshwater. A freshwater flux of 40.4 ± 4.9×109 m3 y−1 was found (1999–2008), with an 85% contribution originated from ice discharge (65% alone from Helheim Glacier), 11% from terrestrial surface runoff (from melt water and rain), 3% from precipitation at the fjord surface area, and 1% from subglacial geothermal and frictional melting due to basal ice motion. The results demonstrate the dominance of ice discharge as a primary mechanism for delivering freshwater to Sermilik Fjord. Time series of ice discharge for Helheim Glacier, Midgard Glacier, and Fenris Glacier were calculated from satellite-derived average surface velocity, glacier width, and estimated ice thickness, and fluctuations in terrestrial surface freshwater runoff were simulated based on observed meteorological data. These simulations were compared and bias corrected against independent glacier catchment runoff observations. Modeled runoff to Sermilik Fjord was variable, ranging from 2.9 ± 0.4×109 m3 y−1 in 1999 to 5.9 ± 0.9×109 m3 y−1 in 2005. The sub-catchment runoff of the Helheim Glacier region accounted for 25% of the total runoff to Sermilik Fjord. The runoff distribution from the different sub-catchments suggested a strong influence from the spatial variation in glacier coverage, indicating high runoff volumes, where glacier cover was present at low elevations.