Channelized Melting Drives Thinning Under a Rapidly Melting Antarctic Ice Shelf
Channelized Melting Drives Thinning Under a Rapidly Melting Antarctic Ice Shelf
复制标题
DOI：
10.1002/2017gl074929
复制
发表时间：
2017-10-16
影响因子：
5.2
通讯作者：
van de Berg, Willem Jan
中科院分区：
文献类型：
--
作者：
Gourmelen, Noel;Goldberg, Dan N.;van de Berg, Willem Jan
冰架在调节冰的损失和向沿海提供淡水方面发挥着至关重要的作用。然而，冰架内的融化变异性约束不佳，可能有助于推动冰架不平衡和崩溃。从2010年到2016年的高分辨率测高测量显示，南极洲西部的Dotson冰架（DIS）由于基底融化而变薄，集中在沿着一个5公里宽，60公里长的通道，从冰架的接地区延伸到其崩解前沿。如果集中减薄继续以目前的速度进行，海峡将在40- 50年内融化，冰架将崩溃，从平均减薄速度预测，几乎两个世纪前崩溃。我们的研究结果提供了证据的基础融化驱动子冰架通道的形成和它的潜力，加速冰架的削弱。简单的语言摘要冰架作为安全带周围的南极冰盖。许多冰架目前正在变薄，导致后面的地面冰加速。在这里，我们表明，冰架的减薄是强烈的沿着一个通道结构所形成的海洋环流下的冰架。冰架变薄的程度是平均冰架变薄程度的3倍，因此导致冰架更快地变弱。这项研究提供了证据的基础融化驱动子冰架通道的形成和它的潜力，加速冰架的削弱。
Ice shelves play a vital role in regulating loss of grounded ice and in supplying freshwater to coastal seas. However, melt variability within ice shelves is poorly constrained and may be instrumental in driving ice shelf imbalance and collapse. High-resolution altimetry measurements from 2010 to 2016 show that Dotson Ice Shelf (DIS), West Antarctica, thins in response to basal melting focused along a single 5km-wide and 60km-long channel extending from the ice shelf's grounding zone to its calving front. If focused thinning continues at present rates, the channel will melt through, and the ice shelf collapse, within 40-50years, almost two centuries before collapse is projected from the average thinning rate. Our findings provide evidence of basal melt-driven sub-ice shelf channel formation and its potential for accelerating the weakening of ice shelves.Plain Language Summary Ice shelves act as safety bands around the Antarctic ice sheet. Many ice shelves are currently thinning, leading to acceleration of the grounded ice behind. Here we show that ice shelves' thinning is stronger along a channel structure formed by the ocean circulation under the ice shelf. The thinning is 3 times higher than the ice shelf's average, hence leading to a more rapid weakening of the ice shelf. This study provides evidence of basal melt-driven sub-ice shelf channel formation and its potential for accelerating the weakening of ice shelves.