Variable temperature thresholds of melt pond formation on Antarctic ice shelves
Variable temperature thresholds of melt pond formation on Antarctic ice shelves
复制标题
南极冰架上融化池形成的可变温度阈值
DOI：
10.1038/s41558-022-01577-1
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发表时间：
2023
影响因子：
30.7
通讯作者：
S. Lhermitte
中科院分区：
文献类型：
--
作者：
J. M. van Wessem;M. R. van den Broeke;B. Wouters;S. Lhermitte
冰架融化是保证冰架稳定的重要环节。在这里，作者估计了南极冰架上融化积水出现的温度阈值，并发现寒冷和干燥的冰架比预期更容易融化积水。有人认为，−5 °C年平均2 m气温等温线定义了南极半岛冰架生存的极限，因为在较高的温度下，融化积水增加。然而，目前尚不清楚这一门槛是否也适用于其他南极冰架。在这里，我们使用两个现在和三个未来的高分辨率南极气候模拟来预测南极冰架融化池塘形成的升温阈值。相关的升温阈值与观测到的融化池塘的体积很好地匹配，并被发现在空间上高度可变，并受积雪的控制。对于相对潮湿的冰架，−5 °C的温度阈值得到了确认；但冷冰架和干冰架，如阿莫里、罗斯和费尔奇纳-罗恩，比之前认为的更脆弱，阈值温度远低于−15 °C。耦合模式比较项目第六阶段模型预测，到本世纪末，许多冰架可能会达到这些阈值，即使是在寒冷的冰架和中等变暖的情况下。
Melt ponding is an important process for the stability of ice shelves. Here the authors estimate the temperature thresholds at which melt ponding emerges over Antarctic ice shelves and find that cold and dry ice shelves are more vulnerable to melt ponding than expected. It has been argued that the −5 °C annual mean 2 m air temperature isotherm defines a limit of ice shelf viability on the Antarctic Peninsula as melt ponding increases at higher temperatures. It is, however, presently unknown whether this threshold can also be applied to other Antarctic ice shelves. Here we use two present-day and three future high-resolution Antarctic climate simulations to predict warming thresholds for Antarctic ice shelf melt pond formation on the basis of the melt-over-accumulation ratio. The associated warming thresholds match well with observed melt pond volumes and are found to be spatially highly variable and controlled by snow accumulation. For relatively wet ice shelves, the −5 °C temperature threshold was confirmed; but cold and dry ice shelves such as Amery, Ross and Filchner-Ronne are more vulnerable than previously thought, with threshold temperatures well below −15 °C. Coupled Model Intercomparison Project Phase 6 models predict that towards the end of this century these thresholds can be reached on many ice shelves, even on cold ice shelves and under moderate warming scenarios.
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影响因子：
30.7
作者：
Bell, Robin E.;Banwell, Alison F.;Kingslake, Jonathan
通讯作者：
Kingslake, Jonathan
影响因子：
11.4
作者：
Diarmuid Corr;A. Leeson;M. McMillan;Ce Zhang;T. Barnes
通讯作者：
Diarmuid Corr;A. Leeson;M. McMillan;Ce Zhang;T. Barnes
影响因子：
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作者：
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通讯作者：
Wainer, Ilana
影响因子：
30.7
作者：
Fuerst, Johannes Jakob;Durand, Gael;Gagliardini, Olivier
通讯作者：
Gagliardini, Olivier
影响因子：
64.8
作者：
Lai, Ching-Yao;Kingslake, Jonathan;van Wessem, J. Melchior
通讯作者：
van Wessem, J. Melchior