Ice front and flow speed variations of marine-terminating outlet glaciers along the coast of Prudhoe Land, northwestern Greenland
Ice front and flow speed variations of marine-terminating outlet glaciers along the coast of Prudhoe Land, northwestern Greenland
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DOI：
10.1017/jog.2018.20
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发表时间：
2018-03
影响因子：
3.4
通讯作者：
D. Sakakibara;S. Sugiyama
中科院分区：
文献类型：
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作者：
D. Sakakibara;S. Sugiyama
摘要分析了1987年至2014年格陵兰西北部普拉德霍地海岸沿着19个海洋终止出口冰川的锋面位置和冰速。在研究期间，所有研究的冰川都以12至200 m a−1的速度退缩，中位（平均）退缩速度为30（40）m a−1。冰川退缩开始于2000年，这与1996 - 2000年该地区夏季平均气温从1.4 °C上升到5.5 °C相吻合。2014年，研究冰川前端附近的冰速介于20至1740 m a−1之间，其中许多在21世纪初加速。一般来说，在经历更大加速的冰川上观察到更快的退缩，如特雷西冰川，在研究期间经历了200 m a−1的退缩和930 m a−1的速度增加。这一观察结果的一个可能的解释是，流动加速引起的动态变薄附近的终端，从而提高了产犊和研究冰川的快速撤退。我们假设，20世纪90年代末的大气变暖条件引发了自2000年以来格陵兰岛西北部的冰川退缩。
ABSTRACT Satellite images were analyzed to measure the frontal positions and ice speeds of 19 marine-terminating outlet glaciers along the coast of Prudhoe Land, northwestern Greenland from 1987 to 2014. All the studied glaciers retreated over the study period at a rate of between 12 and 200 m a−1, with a median (mean) retreat rate of 30 (40) m a−1. The glacier retreat began in the year ~2000, which coincided with an increase in summer mean air temperature from 1.4 to 5.5 °C between 1996 and 2000 in this region. Ice speed near the front of the studied glaciers ranged between 20 and 1740 m a−1 in 2014, and many of them accelerated in the early 2000s. In general, the faster retreat was observed at the glaciers that experienced greater acceleration, as represented by Tracy Glacier, which experienced a retreat of 200 m a−1 and a velocity increase of 930 m a−1 during the study period. A possible interpretation of this observation is that flow acceleration induced dynamic thinning near the termini, resulting in enhanced calving and rapid retreat of the studied glaciers. We hypothesize that atmospheric warming conditions in the late 1990s triggered glacier retreat in northwestern Greenland since 2000.