Representation of basal melting at the grounding line in ice flow models

Representation of basal melting at the grounding line in ice flow models
复制标题

冰流模型中接地线处基底融化的表示

DOI:
--
复制
发表时间:
2018
期刊:
The Cryosphere
影响因子:
--
通讯作者:
Mathieu Morlighem
Mathieu Morlighem
中科院分区:
--
文献类型:
--
作者:
H. Seroussi;Mathieu Morlighem

文献摘要

参考文献

被引文献

相似文献

抽象的。虽然人们对数值实现给予了很多关注 接地线和接地区域的基本摩擦力,几乎没有 关于海洋引起的基底的数值处理的影响 在这个地区融化。目前正在采用多种策略 冰盖建模社区,以及由此产生的接地线动态 可能存在很大差异,这最终会增加显着的不确定性 海洋冰盖对海平面上升的预计贡献。我们调查 这里是部分基础熔体参数化的几种实现 基于海洋冰的有限元框架中的浮动单元 海洋模型比对项目 (MISOMIP) 设置:(1) 应用熔融 仅适用于完全浮动的元素,(2) 熔化应用于所有元素 与接地线交叉,并且 (3) 部分熔化集成在 使用两个不同子元素的有限元的浮动部分 整合方法。当 网格分辨率足够细。然而,(2)和(3)将系统地 高估了粗略分辨率下接地线撤退的速度,而 (1) 在大多数情况下更快地收敛到解。之间的差异 对于高实验,子元素参数化会加剧 接地线附近和 Weertman 的熔化率 滑动定律。由于大多数现实世界的模拟使用水平网格分辨率 最多可达数百米,并且通常具有较高的熔化速率 靠近接地线,我们建议不要使用(3)以避免 高估接地线撤退速度并仔细评估 网格分辨率和子单元熔化参数化对所有的影响 模拟结果。
Abstract. While a lot of attention has been given to the numerical implementation of grounding lines and basal friction in the grounding zone, little has been done about the impact of the numerical treatment of ocean-induced basal melting in this region. Several strategies are currently being employed in the ice sheet modeling community, and the resulting grounding line dynamics may differ strongly, which ultimately adds significant uncertainty to the projected contribution of marine ice sheets to sea level rise. We investigate here several implementations of basal melt parameterization on partially floating elements in a finite-element framework, based on the Marine Ice Sheet–Ocean Model Intercomparison Project (MISOMIP) setup: (1) melt applied only to entirely floating elements, (2) melt applied over all elements that are crossed by the grounding line, and (3) melt integrated partially over the floating portion of a finite element using two different sub-element integration methods. All methods converge towards the same state when the mesh resolution is fine enough. However, (2) and (3) will systematically overestimate the rate of grounding line retreat in coarser resolutions, while (1) converges faster to the solution in most cases. The differences between sub-element parameterizations are exacerbated for experiments with high melting rates in the vicinity of the grounding line and for a Weertman sliding law. As most real-world simulations use horizontal mesh resolutions of several hundreds of meters at best, and high melt rates are generally present close to the grounding lines, we recommend not using (3) to avoid overestimating the rate of grounding line retreat and to carefully assess the impact of mesh resolution and sub-element melt parameterizations on all simulation results.
DOI: 10.1038/nclimate2094
发表时间: 2014-02-01
影响因子: 30.7
作者:
Favier, L.;Durand, G.;Le Brocq, A. M.
通讯作者: Le Brocq, A. M.
DOI: 10.1038/nature15706
发表时间: 2015-10-15
期刊: NATURE
影响因子: 64.8
作者:
Golledge, N. R.;Kowalewski, D. E.;Gasson, E. G. W.
通讯作者: Gasson, E. G. W.
DOI: 10.5194/tc-6-1497-2012
发表时间: 2012-01-01
期刊: CRYOSPHERE
影响因子: 5.2
作者:
Gudmundsson, G. H.;Krug, J.;Gagliardini, O.
通讯作者: Gagliardini, O.
DOI: 10.5194/tc-7-647-2013
发表时间: 2013-01-01
期刊: CRYOSPHERE
影响因子: 5.2
作者:
Gudmundsson, G. H.
通讯作者: Gudmundsson, G. H.
DOI: 10.1002/2017gl072514
发表时间: 2017-03-16
影响因子: 5.2
作者:
Arthern, Robert J.;Williams, C. Rosie
通讯作者: Williams, C. Rosie