Regional sea-level highstand triggered Holocene ice sheet thinning across coastal Dronning Maud Land, East Antarctica
Regional sea-level highstand triggered Holocene ice sheet thinning across coastal Dronning Maud Land, East Antarctica
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区域海平面高位引发南极洲东部德隆莫德地沿海全新世冰盖变薄
DOI：
10.1038/s43247-022-00599-z
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发表时间：
2022
影响因子：
7.9
通讯作者：
Harbor Jona
中科院分区：
文献类型：
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作者：
Suganuma Yusuke;Kaneda Heitaro;Mas e Braga Martim;Ishiwa Takeshige;Koyama Takushi;Newall Jennifer C.;Okuno Jun’ichi;Obase Takashi;Saito Fuyuki;Rogozhina Irina;Andersen Jane Lund;Kawamata Moto;Hirabayashi Motohiro;Lifton Nathaniel A.;Fredin Ola;Harbor Jona
东南极冰盖储存了大量的淡水，这使其成为未来海平面上升的最大潜在贡献者。然而，缺乏良好的约束过去冰盖变化的地质记录阻碍了模型验证，妨碍质量平衡估计，并抑制检查冰损失机制。在这里，我们确定快速冰盖变薄在沿海德龙宁毛德地早至中全新世（9000-5000年前）使用的冰川消退年表的基础上，在现场宇宙成因核素表面暴露日期从中央德龙宁毛德地，与区域和大陆冰盖演变的数值模拟。从我们精确的冰负荷历史再现的区域海平面变化显示在9000-8000年前的高点。我们认为，海平面上升和随之而来的温暖的环极深水的涌入引发冰架破裂通过海洋冰盖不稳定机制，导致快速变薄的上游沿海冰盖部门。
The East Antarctic Ice Sheet stores a vast amount of freshwater, which makes it the single largest potential contributor to future sea-level rise. However, the lack of well-constrained geological records of past ice sheet changes impedes model validation, hampers mass balance estimates, and inhibits examination of ice loss mechanisms. Here we identify rapid ice-sheet thinning in coastal Dronning Maud Land from Early to Middle Holocene (9000–5000 years ago) using a deglacial chronology based on in situ cosmogenic nuclide surface exposure dates from central Dronning Maud Land, in concert with numerical simulations of regional and continental ice-sheet evolution. Regional sea-level changes reproduced from our refined ice-load history show a highstand at 9000–8000 years ago. We propose that sea-level rise and a concomitant influx of warmer Circumpolar Deep Water triggered ice shelf breakup via the marine ice sheet instability mechanism, which led to rapid thinning of upstream coastal ice sheet sectors.