Collaborative Research: Do Ocean Wave Impacts Pose a Hazard to the Stability of West Antarctic Ice Shelves?

合作研究：海浪冲击是否会对南极西部冰架的稳定性造成危害？

基本信息

批准号：
1744759
负责人：
Eric Dunham
金额：
$ 22.27万
依托单位：
Stanford University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2018
资助国家：
美国
起止时间：
2018-06-01 至 2022-05-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1744759&HistoricalAwards=false
关键词：
Collaborative Research Do Ocean Wave

项目摘要

Understanding and being able to more reliably forecast ice mass loss from Antarctica is a critical research priority for Antarctic Science. Massive ice shelves buttress marine terminating glaciers, slowing the rate that land ice reaches the sea and, in turn, restraining the rate of sea level rise. To date, most work has focused on the destabilizing impacts of warmer air and water temperatures, resulting in melting that thins and weakens ice shelves. However, recent findings indicate that sea ice does not protect ice shelves from wave impacts as much as previously thought, which has raised the possibility that tsunamis and other ocean waves could affect shelf stability. This project will assess the potential for increased shelf fracturing from the impact of tsunamis and from heightened wave activity due to climate-driven changes in storm patterns and reduced sea-ice extent by developing models to investigate how wave impacts damage ice shelves. The modeling effort will allow for regional comparisons between large and small ice shelves, and provide an evaluation of the impacts of changing climate and storm patterns on ice shelves, ice sheets, glaciers, and, ultimately, sea level rise. This project will train graduate students in mathematical modeling and interdisciplinary approaches to Earth and ocean sciences.This project takes a four-pronged approach to estimating the impact of vibrations on ice shelves at the grounding zone due to tsunamis, very long period, infragravity, and storm-driven waves. First, the team will use high-resolution tsunami modeling to investigate the response of ice shelves along the West Antarctic coast to waves originating in different regions of the Pacific Ocean. Second, it will compare the response to wave impacts on grounding zones of narrow and wide ice shelves. Third, it will assess the exposure risk due to storm forcing through a reanalysis of weather and wave model data; and, finally, the team will model the propagation of ocean-wave-induced vibrations in the ice from the shelf front to and across the grounding zone. In combination, this project aims to identify locations along the Antarctic coast that are subject to enhanced, bathymetrically-focused, long-period ocean-wave impacts. Linkages between wave impacts and climate arise from potential changes in sea-ice extent in front of shelves, and changes in the magnitude, frequency, and tracks of storms. Understanding the effects of ocean waves and climate on ice-shelf integrity is critical to anticipate their contribution to the amplitude and timing of sea-level rise. Wave-driven reductions in ice-shelf stability may enhance shelf fragmentation and iceberg calving, reducing ice shelf buttressing and eventually accelerating sea-level rise.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.

了解并能够更可靠地预测南极洲的冰量损失是南极科学的一项重要研究重点。巨大的冰架支撑着海洋终端冰川，减缓了陆地冰到达海洋的速度，进而抑制了海平面上升的速度。迄今为止，大多数工作都集中在气温升高和水温升高所造成的不稳定影响上，这些影响会导致冰架融化而变薄和削弱。然而，最近的研究结果表明，海冰并不能像以前认为的那样保护冰架免受波浪影响，这增加了海啸和其他海浪可能影响冰架稳定性的可能性。该项目将通过开发模型来研究海浪影响如何破坏冰架，从而评估海啸影响以及气候驱动的风暴模式变化和海冰范围缩小导致的波浪活动加剧所导致的陆架破裂增加的可能性。建模工作将允许对大冰架和小冰架进行区域比较，并评估气候变化和风暴模式对冰架、冰盖、冰川以及最终海平面上升的影响。该项目将培训研究生数学建模以及地球和海洋科学的跨学科方法。该项目采用四管齐下的方法来估计由于海啸、超长周期、次重力和风暴驱动的波浪。首先，该团队将使用高分辨率海啸模型来研究南极西海岸冰架对源自太平洋不同地区的海浪的反应。其次，它将比较窄冰架和宽冰架接地区对波浪影响的响应。第三，它将通过对天气和波浪模型数据的重新分析来评估风暴强迫造成的暴露风险；最后，该团队将模拟海浪引起的冰中振动从大陆架前沿到并穿过接地区的传播。总而言之，该项目旨在确定南极海岸沿线遭受增强的、以测深为重点的长期海浪影响的位置。波浪影响与气候之间的联系源于陆架前海冰范围的潜在变化，以及风暴的强度、频率和路径的变化。了解海浪和气候对冰架完整性的影响对于预测它们对海平面上升幅度和时间的影响至关重要。波浪驱动的冰架稳定性降低可能会加剧冰架破碎和冰山崩解，减少冰架支撑并最终加速海平面上升。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力优势和能力进行评估，被认为值得支持。更广泛的影响审查标准。