海洋冰调节着南极一个大型冰架未来的稳定性。

Marine ice regulates the future stability of a large Antarctic ice shelf.

作者信息

Kulessa Bernd, Jansen Daniela, Luckman Adrian J, King Edward C, Sammonds Peter R

机构信息

Glaciology Group, College of Science, Swansea University, Singleton Park, Swansea SA2 8PP, UK.

1] Glaciology Group, College of Science, Swansea University, Singleton Park, Swansea SA2 8PP, UK [2].

出版信息

Nat Commun. 2014 Apr 22;5:3707. doi: 10.1038/ncomms4707.

DOI:10.1038/ncomms4707

PMID:24751641

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC3997805/

Abstract

The collapses of the Larsen A and B ice shelves on the Antarctic Peninsula in 1995 and 2002 confirm the impact of southward-propagating climate warming in this region. Recent mass and dynamic changes of Larsen B's southern neighbour Larsen C, the fourth largest ice shelf in Antarctica, may herald a similar instability. Here, using a validated ice-shelf model run in diagnostic mode, constrained by satellite and in situ geophysical data, we identify the nature of this potential instability. We demonstrate that the present-day spatial distribution and orientation of the principal stresses within Larsen C ice shelf are akin to those within pre-collapse Larsen B. When Larsen B's stabilizing frontal portion was lost in 1995, the unstable remaining shelf accelerated, crumbled and ultimately collapsed. We hypothesize that Larsen C ice shelf may suffer a similar fate if it were not stabilized by warm and mechanically soft marine ice, entrained within narrow suture zones.

摘要

1995年和2002年南极半岛拉森A和B冰架的崩塌证实了该地区向南传播的气候变暖的影响。拉森B冰架的南部邻居、南极洲第四大冰架拉森C最近的质量和动态变化，可能预示着类似的不稳定情况。在此，我们使用一个经过验证的在诊断模式下运行的冰架模型，该模型由卫星和实地地球物理数据约束，来确定这种潜在不稳定的性质。我们证明，拉森C冰架内主应力的当前空间分布和方向类似于崩塌前的拉森B冰架内的情况。1995年，当拉森B冰架稳定的前沿部分消失时，不稳定的剩余冰架加速、破碎并最终崩塌。我们推测，如果拉森C冰架没有被夹带在狭窄缝合带内的温暖且机械性质柔软的海冰所稳定，它可能会遭遇类似的命运。