A Study of the Tidal Modulation of Ice-shelf Flow using a Viscoelastic Model of the Ross Ice Shelf

利用罗斯冰架粘弹性模型研究冰架流的潮汐调节

• 批准号: 1443320
• 负责人: Kelly Brunt
• 金额: $ 8.09万
• 依托单位: University of Maryland, College Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-04-01 至 2018-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1443320&HistoricalAwards=false
• 关键词: Study; Tidal; Modulation; Ice; shelf

This award supports a two-year study of the flow of the Ross Ice Shelf, Antarctica, which is the portion of the Antarctic ice sheet that is floating on the Ross Sea. The Ross Ice Shelf (along with the Filchner-Ronne Ice Shelf) provides an important, stabilizing back-pressure on the seaward flow of the West Antarctic Ice Sheet, which is the portion of the Antarctic ice sheet that is most at risk of catastrophic disintegration. The study aims to understand the interaction between the Ross Ice Shelf and the ocean by developing a map-plane two-dimensional, viscoelastic, ice-flow model. This model will explore the tidal modulation of mean, time-averaged ice-shelf flow velocity. The model will then be assessed based on GPS measurements that have previously been collected in the field, at a site near the center of the seaward, iceberg-calving front of the ice shelf. The results of this ice-dynamics study will contribute significantly to the ice-sheet modeling community by: 1) providing an independent assessment of both the viscous and elastic components of the ice-shelf response to the ocean tide; 2) providing a better understanding of the sensitivities of the coupled ocean/ice-shelf system; and 3) incorporating both viscous and elastic elements into an integrated ocean/ice-shelf/ice-stream system that addresses tidal modulation of the flow of glacial ice across the grounding line. Having an increased understanding of the ice-shelf-flow dynamics, and an understanding of the teleconnection between the ice shelves and the ice sheets via the ice streams, will assist ice-sheet modelers to better understand the evolution of the West Antarctic Ice Sheet, which is currently the largest Antarctic contribution to mean-sea-level rise.

该奖项支持对南极洲罗斯冰架流动的两年研究，该冰架是漂浮在罗斯海上的南极冰盖的一部分。罗斯冰架（沿着菲尔希纳-龙恩冰架）对西南极冰盖的向海流动提供了重要的稳定背压，西南极冰盖是南极冰盖中最有可能发生灾难性解体的部分。 这项研究的目的是了解罗斯冰架和海洋之间的相互作用，通过开发一个地图平面二维，粘弹性，冰流模型。该模型将探讨潮汐调制的平均，时间平均冰架流速。然后，将根据先前在该领域收集的GPS测量结果对该模型进行评估，该测量结果位于靠近海中心的冰架冰山崩解前沿。这一冰动力学研究的结果将对冰盖模拟界作出重大贡献，因为：1）提供了对冰架对海潮响应的粘性和弹性分量的独立评估; 2）提供了对耦合海洋/冰架系统敏感性的更好理解;以及3）将粘性和弹性元件结合到一体化的海洋/冰架/冰流系统中，该系统解决跨越接地线的冰川冰流动的潮汐调制。增加对冰架流动动力学的了解，并了解冰架和冰盖之间通过冰流的遥相关，将有助于冰盖建模者更好地了解南极西部冰盖的演变，这是目前南极对平均海平面上升的最大贡献。