CAREER: Fracture Mechanics of Antarctic Ice Shelves and Glaciers - Representing Iceberg Calving in Ice Sheet Models and Developing Cyberlearning Tools for Outreach

职业：南极冰架和冰川的断裂力学 - 在冰盖模型中代表冰山崩解并开发用于推广的网络学习工具

基本信息

批准号：
1847173
负责人：
Ravindra Duddu
金额：
$ 55.5万
依托单位：
Vanderbilt University
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
2019
资助国家：
美国
起止时间：
2019-04-01 至 2025-03-31
项目状态：
未结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1847173&HistoricalAwards=false
关键词：
CAREER Fracture Mechanics Antarctic Ice

项目摘要

Iceberg calving is a complex natural fracture process and a dominant cause of mass loss from the floating ice shelves on the margins of the Antarctic ice sheet. There is concern that rapid changes at these ice shelves can destabilize parts of the ice sheet and accelerate their contribution to sea-level rise. The goal of this project is to understand and simulate the fracture mechanics of calving and to develop physically-consistent calving schemes for ice-sheet models. This would enable more reliable estimation of Antarctic mass loss by reducing the uncertainty in projections. The research plan is integrated with an education and outreach plan that aims to (1) enhance computational modeling skills of engineering and Earth science students through a cross-college course and a high-performance computing workshop and (2) increase participation and diversity in engineering and sciences by providing interdisciplinary research opportunities to undergraduates and by deploying new cyberlearning tools to engage local K-12 students in the Metro Nashville Public Schools in computational science and engineering, and glaciology.This project aims to provide fundamental understanding of iceberg calving by advancing the frontiers in computational fracture mechanics and nonlinear continuum mechanics and translating it to glaciology. The project investigates crevasse propagation using poro-damage mechanics models for hydrofracture that are consistent with nonlinear viscous ice rheology, along with the thermodynamics of refreezing in narrow crevasses at meter length scales. It will develop a fracture-physics based scheme to better represent calving in ice-sheet models using a multiscale method. The effort will also address research questions related to calving behavior of floating ice shelves and glaciers, with the goal of enabling more reliable prediction of calving fronts in whole-Antarctic ice-sheet simulations over decadal-to-millennial time scales.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.

冰山产犊是一个复杂的自然断裂过程，也是南极冰盖边缘浮冰架上质量损失的主要原因。人们担心这些冰架的快速变化会破坏冰盖的一部分，并加速其对海平面上升的贡献。该项目的目的是了解和模拟产犊的断裂力学，并为冰盖模型开发出良好的产犊方案。这将通过减少投影的不确定性来实现对南极质量损失的更可靠估计。该研究计划与教育和外展计划融合，旨在通过跨大学课程和高性能计算研讨会来增强工程和地球科学专业学生的计算建模技能，以及（2）增加工程学的参与和多样性和科学通过为大学生提供跨学科的研究机会，并通过部署新的网络学习工具来吸引当地的K-12学生在计算科学和工程的地铁公立学校中，以及冰川学。计算断裂力学和非线性连续性力学的前沿，并将其转化为冰川学。该项目使用与非线性粘性冰流变性一致的孔隙骨折的孔隙破坏力学模型研究裂缝繁殖，以及在米长度尺度下在窄曲面中重新冻结的热力学。它将开发基于骨折的方案，以更好地代表使用多尺度方法在冰盖模型中的产犊。这项努力还将解决与浮冰架和冰川的产犊行为有关的研究问题，目的是使在十年到千年到千年的时间尺度上更可靠地预测对整个无二十分冰淇淋模拟的产犊前沿的预测。这一奖项反映了NSF的奖项法定任务，并被认为是值得通过基金会的智力优点和更广泛影响的审查标准来评估的值得支持的。