Ocean-Forced Ice-Shelf Thinning in a Synchronously Coupled Ice-Ocean Model
Ocean-Forced Ice-Shelf Thinning in a Synchronously Coupled Ice-Ocean Model
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DOI：
10.1002/2017jc013251
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发表时间：
2018-02-01
影响因子：
3.6
通讯作者：
Jenkins, Adrian
中科院分区：
文献类型：
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作者：
Jordan, James R.;Holland, Paul R.;Jenkins, Adrian
第一个完全同步的、耦合的冰架-海洋模型，具有固定的接地线和强加的上游冰速度，已经使用MITgcm（麻省理工学院一般环流模型）开发出来。与以前的异步耦合建模方法不同，我们的方法对热、盐和质量是完全保守的。通过在海洋时间步长上不断更新冰架厚度来实现同步耦合。通过模拟一个理想的温水冰架，我们展示了斜倾角的升高如何导致冰架质量和背应力的减少，从而导致支撑。耦合运行表明，由于科里奥利流增强，西部边界的融化增加，在冰架底部形成了一个西部边界通道。东部边界冰也增厚。当使用简单的与深度相关的参数化融化时，情况并非如此，因为对于给定的冰架质量，冰架具有相对较薄的边和较厚的中央凸起。与耦合模式模拟相比，由于边界处的冰架较薄，由参数化融化速率引起的冰架几何形状往往低估了给定冰架质量的背应力（从而低估了支撑作用）。
The first fully synchronous, coupled ice shelf-ocean model with a fixed grounding line and imposed upstream ice velocity has been developed using the MITgcm (Massachusetts Institute of Technology general circulation model). Unlike previous, asynchronous, approaches to coupled modeling our approach is fully conservative of heat, salt, and mass. Synchronous coupling is achieved by continuously updating the ice-shelf thickness on the ocean time step. By simulating an idealized, warm-water ice shelf we show how raising the pycnocline leads to a reduction in both ice-shelf mass and back stress, and hence buttressing. Coupled runs show the formation of a western boundary channel in the ice-shelf base due to increased melting on the western boundary due to Coriolis enhanced flow. Eastern boundary ice thickening is also observed. This is not the case when using a simple depth-dependent parameterized melt, as the ice shelf has relatively thinner sides and a thicker central bulge for a given ice-shelf mass. Ice-shelf geometry arising from the parameterized melt rate tends to underestimate backstress (and therefore buttressing) for a given ice-shelf mass due to a thinner ice shelf at the boundaries when compared to coupled model simulations.