The impact of 3-D Earth structure on far-field sea level following interglacial West Antarctic Ice Sheet collapse
The impact of 3-D Earth structure on far-field sea level following interglacial West Antarctic Ice Sheet collapse
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间冰期南极西部冰盖塌陷后 3D 地球结构对远场海平面的影响
DOI：
10.1016/j.quascirev.2021.107256
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发表时间：
2021
影响因子：
4
通讯作者：
Mitrovica, Jerry X.
中科院分区：
文献类型：
--
作者：
Powell, Evelyn M.;Pan, Linda;Hoggard, Mark J.;Latychev, Konstantin;Gomez, Natalya;Austermann, Jacqueline;Mitrovica, Jerry X.
在从过去的间冰期海平面记录推断冰盖稳定性之前，这些记录必须首先校正冰川均衡调整（GIA）的污染影响。然而，典型的GIA校正忽略了可能由地球的3-D流变结构引入的信号变化。我们预测海平面的变化，由于崩溃的西南极冰盖（WAIS）在一个理想的6千年持续时间的间冰期使用四个粘弹性地球模型。其中两个是从地震层析成像推断的3-D粘度模型。第三个是1-D（即，深度变化）粘度模型，其等效于在两个3-D地球模型中采用的球形平均“背景”粘度分布。第四个是1-D模型，具有较高的上地幔粘度，但仍然福尔斯类模型推断独立的全球GIA研究。我们发现，3-D和1-D地球模型计算的海平面在远场的熔融区之间的差异是为了0.3米或更少，与1-D地球模型产生更高的海平面比3-D模拟。这个数值是全球平均海平面（GMSL）上升的10%，与模型间冰期（103米）结束时的模拟冰盖崩溃和远场海平面变化的相似部分。然而，该值是地理变量（即，与模型WAIS塌陷相关的GIA导致的远场海平面信号的非GMSL）分量（±0.5 m）。在模拟间冰期期间WAIS过度融化的响应时忽略地球结构的横向变化，会使由前一次冰期循环驱动的间冰期海平面变化预测中忽略这种结构所引入的任何误差复合。
Prior to inferring ice sheet stability from past interglacial sea-level records, these records must first be corrected for the contaminating effects of glacial isostatic adjustment (GIA). Typical GIA corrections, however, neglect variability in the signal that may be introduced by Earth's 3-D rheological structure. We predict sea-level changes due to a collapse of the West Antarctic Ice Sheet (WAIS) over an idealized 6 kyr-duration interglacial using four viscoelastic Earth models. Two of these are 3-D viscosity models inferred from seismic tomography. The third is a 1-D (i.e., depth varying) viscosity model that is equivalent to the spherically averaged “background” viscosity profile adopted in both 3-D Earth models. The fourth is a 1-D model that has a higher upper mantle viscosity but still falls within the class of models inferred from independent global GIA studies. We find that the discrepancy between 3-D and 1-D Earth model calculations of sea level in the far field of the melt zone is of order 0.3 m or less, with the 1-D Earth models producing higher sea level than the 3-D simulations. This value is 10% of the global mean sea-level (GMSL) rise associated with modeled ice sheet collapse by the end of the model interglacial (∼3 m) and a similar fraction of far-field sea-level changes. However, the value is a significantly larger fraction (∼60%) of the geographically variable (i.e., non-GMSL) component of the far-field sea-level signal due to GIA associated with modeled WAIS collapse (±0.5 m). Neglecting lateral variations in Earth structure in modeling the response to excess melting of WAIS during the interglacial compounds any error introduced by neglecting such structure in predictions of interglacial sea-level change driven by the preceding glacial cycle.
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冰盖-地球-海平面耦合模型中南极冰盖的变化：对地球粘弹性特性的敏感性
DOI：
--
发表时间：
2017
期刊：
影响因子：
--
作者：
D. Pollard;N. Gomez;R. DeConto
通讯作者：
R. DeConto
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DOI：
--
发表时间：
2013
期刊：
影响因子：
--
作者：
M. O’Leary;P. Hearty;W. Thompson;M. Raymo;J. Mitrovica;J. Webster
通讯作者：
J. Webster
影响因子：
16.6
作者：
Gomez N;Pollard D;Holland D
通讯作者：
Holland D
影响因子：
13.6
作者：
Pan L;Powell EM;Latychev K;Mitrovica JX;Creveling JR;Gomez N;Hoggard MJ;Clark PU
通讯作者：
Clark PU
影响因子：
2.8
作者：
Crawford, Ophelia;Al-Attar, David;Lau, Harriet C. P.
通讯作者：
Lau, Harriet C. P.