Satellite Observations and Modelling of Surface Meltwater Flow and its Impact on Ice Shelves

表面融水流及其对冰架影响的卫星观测和建模

• 批准号: 1743310
• 负责人: Jonathan Kingslake
• 金额: $ 53.59万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-08-01 至 2023-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1743310&HistoricalAwards=false
• 关键词: Satellite; Observations; Modelling; Surface; Meltwater

Ice shelves slow the movement of the grounded ice sheets that feed them. This reduces the rate at which ice sheets lose mass to the oceans and contribute to sea-level rise. But ice shelves can be susceptible to collapse, particularly when surface meltwater accumulates in vulnerable areas. Meltwater lakes can create and enlarge fractures within the ice shelves, thereby triggering or hastening ice-shelf collapse. Also, water refreezing within ice shelves warms the ice and could affect the flow of the ice by changing its viscosity, which depends on temperature. The drainage of water across the surface of Antarctica and where it accumulates has received little attention. This drainage was assumed to be insignificant, but recent work shows that meltwater can drain for tens of kilometers across ice-shelf surfaces and access areas that would otherwise not accumulate meltwater. Surface meltwater drainage could play a major role in the future stability of ice sheets. This drainage is the focus of this project. The team will develop and test physics-based mathematical models of water flow and ice-shelf flow, closely informed by remote sensing observations, to ask (1) how drainage systems will grow in response to the increased melt rates that are predicted for this century, (2) how this drainage is influenced by ice dynamics and (3) whether enlarged drainage systems could deliver meltwater to areas of ice shelves that are vulnerable to water-driven collapse. The team hypothesizes that refreezing of meltwater in snow and firn will prove important for hydrology by impacting the permeability of the snow/firn and for ice-shelf dynamics by releasing latent heat within the ice and lowering ice viscosity. The project will examine these issues by (1) conducting a remote sensing survey of the structure and temporal evolution of meltwater systems around Antarctica, (2) developing and analyzing mathematical models of water flow across ice shelves, and (3) examining idealized and realistic models of ice-shelf flow. This project will support a first-time NSF PI, a post-doctoral researcher and a graduate student. An outreach activity will make use of the emerging technology of Augmented Reality to visualize the dynamics of ice sheets in three dimensions to excite the public about glaciology at outreach events around New York City. This approach will be made publicly available for wider use as Augmented Reality continues to grow in popularity.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

冰架减慢了喂食它们的接地冰盖的运动。这降低了冰盖在海洋上失去质量的速度，并导致海平面上升。但是冰架可能容易倒塌，尤其是当地面融合水在脆弱的地区积聚时。融化湖泊可以在冰架上产生和扩大裂缝，从而引发或加速冰壳倒塌。同样，在冰架上重新冰冷的水会变暖冰，并可能通过改变粘度来影响冰的流动，这取决于温度。水在南极洲的表面及其积聚的地方引流很少受到关注。假定这种排水量微不足道，但最近的工作表明，融合水可以在冰架表面上排出数十公里，并进入否则不会累积融化的区域。地面融合水排水可能在未来的冰盖稳定性中起主要作用。这种排水是该项目的重点。该团队将开发和测试基于物理的水流和冰架流的数学模型，并通过遥感观测值密切获取，以询问（1）排水系统如何增长，以应对本世纪预测的融化速率的提高。 ，（2）这种排水如何受冰动力学的影响，以及（3）排水系统扩大是否可以将融化水输送到容易受到水驱动塌陷的冰架区域。 该小组假设，通过影响雪/FIRN的渗透性以及通过在冰中释放潜热并降低冰粘度来影响雪和FIRN中的融水对水文的重新冻结对水文很重要。该项目将通过（1）对南极洲周围的融化系统的结构和时间演变进行遥感调查，（2）开发和分析跨冰架上的水流的数学模型，以及（3）检查理想和现实化的数学模型冰架流的模型。该项目将支持首次NSF PI，博士后研究人员和研究生。推广活动将利用新兴的增强现实技术，以在纽约市附近的外展活动中，在三个维度上可视化冰盖的动态，以激发公众的冰川学。 随着增强现实的普及，这种方法将公开用于更广泛的用途。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子优点和更广泛的影响审查标准通过评估来支持的。

项目成果

Can unconfined ice shelves provide buttressing via hoop stresses?

无约束冰架可以通过环向应力提供支撑吗？

• DOI: 10.1017/jog.2019.101
• 发表时间: 2020
• 期刊: Journal of Glaciology
• 影响因子: 3.4
• 作者: Wearing, Martin G.;Kingslake, Jonathan;Worster, M. Grae
• 通讯作者: Worster, M. Grae

Surface meltwater drainage and ponding on Amery Ice Shelf, East Antarctica, 1973–2019

1973 年至 2019 年东南极洲埃默里冰架表面融水排水和积水

• DOI: 10.1017/jog.2021.46
• 发表时间: 2021
• 期刊: Journal of Glaciology
• 影响因子: 3.4
• 作者: Spergel, Julian J.;Kingslake, Jonathan;Creyts, Timothy;van Wessem, Melchior;Fricker, Helen A.
• 通讯作者: Fricker, Helen A.

ICESat‐2 Meltwater Depth Estimates: Application to Surface Melt on Amery Ice Shelf, East Antarctica

• DOI: 10.1029/2020gl090550
• 发表时间: 2020-12
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: H. Fricker;Philipp Arndt;K. Brunt;R. Datta;Z. Fair;M. Jasinski;J. Kingslake;L. Magruder;M. Moussavi;A. Pope;J. Spergel;J. Stoll;B. Wouters

Ice‐Shelf Basal Melt Channels Stabilized by Secondary Flow

二次流稳定的冰架基底融化通道

• DOI: 10.1029/2021gl094872
• 发表时间: 2021
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: Wearing, M. G.;Stevens, L. A.;Dutrieux, P.;Kingslake, J.
• 通讯作者: Kingslake, J.

Inside the ice shelf: using augmented reality to visualise 3D lidar and radar data of Antarctica

冰架内部：使用增强现实可视化南极洲的 3D 激光雷达和雷达数据

• DOI: 10.1111/phor.12298
• 发表时间: 2019
• 期刊: The Photogrammetric Record
• 作者: Boghosian, Alexandra L.;Pratt, Martin J.;Becker, Maya K.;Cordero, S. Isabel;Dhakal, Tejendra;Kingslake, Jonathan;Locke, Caitlin D.;Tinto, Kirsty J.;Bell, Robin E.
• 通讯作者: Bell, Robin E.