Hydrostatic grounding line parameterization in ice sheet models
Hydrostatic grounding line parameterization in ice sheet models
复制标题
冰盖模型中的静压接地线参数化
DOI：
--
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
A. Khazendar
中科院分区：
文献类型：
--
作者：
H. Seroussi;M. Morlighem;E. Larour;E. Rignot;A. Khazendar
接地线迁移建模对于准确模拟海洋冰盖的行为以及研究其稳定性至关重要。在此，我们评估了数值模型对接地线位置参数化的敏感性。我们使用冰盖系统模型（ISSM）和二维浅海流近似（SSA）模型进行了MISMIP3D基准实验，这些模型具有不同的网格分辨率以及不同的接地线位置子单元参数化。结果表明，不同的接地线参数化会导致不同的稳态接地线位置以及不同的后退/前进速率。我们的模拟解释了为什么一些垂直深度平均模型模拟在MISMIP3D基准中与基于SSA的绝大多数模拟有显著偏差。结果显示，在有和无子单元参数化的模拟之间的差异，与在这种配置下应力平衡方程的不同近似所产生的模拟之间的差异一样大。它们还表明，在相对较粗的分辨率下可逆性测试能够通过，然而需要更精细的分辨率才能准确捕捉稳态接地线位置。我们得出结论，应避免使用不采用这种参数化的固定网格SSA模型，因为它们即使在高空间分辨率下也无法提供准确的接地线动力学估计。对于包含子单元接地线参数化的模型，在MISMIP3D配置中，应采用小于2千米的网格分辨率。
Modeling of grounding line migration is essential to accurately simulate the behavior of marine ice sheets and investigate their stability. Here, we assess the sensitivity of numerical models to the parameterization of the grounding line position. We run the MISMIP3D benchmark experiments using the Ice Sheet System Model (ISSM) and a two-dimensional shelfy-stream approximation (SSA) model with different mesh resolutions and different sub-element parameterizations of grounding line position. Results show that different grounding line parameterizations lead to different steady state grounding line positions as well as different retreat/advance rates. Our simulations explain why some vertically depth-averaged model simulations deviate significantly from the vast majority of simulations based on SSA in the MISMIP3D benchmark. The results reveal that differences between simulations performed with and without sub-element parameterization are as large as those performed with different approximations of the stress balance equations in this configuration. They also demonstrate that the reversibility test is passed at relatively coarse resolution while much finer resolutions are needed to accurately capture the steady-state grounding line position. We conclude that fixed grid SSA models that do not employ such a parameterization should be avoided, as they do not provide accurate estimates of grounding line dynamics, even at high spatial resolution. For models that include sub-element grounding line parameterization, in the MISMIP3D configuration, a mesh resolution finer than 2 km should be employed.
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影响因子：
30.7
作者：
Favier, L.;Durand, G.;Le Brocq, A. M.
通讯作者：
Le Brocq, A. M.
影响因子：
2.9
作者：
G. Durand;O. Gagliardini;T. Zwinger;E. L. Meur;R. Hindmarsh
通讯作者：
G. Durand;O. Gagliardini;T. Zwinger;E. L. Meur;R. Hindmarsh
DOI：
10.5194/tc-4-605-2010
发表时间：
2010-12
期刊：
The Cryosphere
影响因子：
--
作者：
R. Gladstone;A. Payne;S. Cornford
通讯作者：
R. Gladstone;A. Payne;S. Cornford
影响因子：
4.1
作者：
Cornford, Stephen L.;Martin, Daniel F.;Lipscomb, William H.
通讯作者：
Lipscomb, William H.