NSF-NERC: PROcesses, drivers, Predictions: Modeling the response of Thwaites Glacier over the next Century using Ice/Ocean Coupled Models (PROPHET)

NSF-NERC：过程、驱动因素、预测：使用冰/海洋耦合模型 (PROPHET) 模拟思韦茨冰川在下个世纪的响应

• 批准号: 2152622
• 负责人: Mathieu Morlighem
• 金额: $ 111.95万
• 依托单位: Dartmouth College
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-15 至 2025-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2152622&HistoricalAwards=false
• 关键词: NSF; NERC; PROcesses; drivers; Predictions

This project contributes to the joint initiative launched by the U.S. National Science Foundation (NSF) and the U.K. Natural Environment Research Council (NERC) to substantially improve decadal and longer-term projections of ice loss and sea-level rise originating from Thwaites Glacier in West Antarctica. Thwaites Glacier has been accelerating and widening over the past three decades. How fast Thwaites will disintegrate or how quickly it will find a new stable state have become some of the most important questions of the future of the West Antarctic Ice Sheet and its contribution to sea-level rise over the next decades to centuries and beyond. This project will rely on three independent numerical models of ice flow, coupled to an ocean circulation model to (1) improve our understanding of the interactions between the ice and the underlying bedrock, (2) analyze how sensitive the glacier is to external changes, (3) assess the processes that may lead to a collapse of Thwaites, and, most importantly, (4) forecast future ice loss of Thwaites. By providing predictions based on a suite of coupled ice-ocean models, this project will also assess the uncertainty in model projections.The project will use three independent ice-sheet models: Ice Sheet System Model, Ua, and STREAMICE, coupled to the ocean circulation model of the MIT General Circulation Model. The team will first focus on the representation of key physical processes of calving, ice damage, and basal slipperiness that have either not been included, or are poorly represented, in previous ice-flow modelling work. The team will then quantify the relative role of different proposed external drivers of change (e.g., ocean-induced ice-shelf thinning, loss of ice-shelf pinning points) and explore the stability regime of Thwaites Glacier with the aim of identifying internal thresholds separating stable and unstable grounding-line retreat. Using inverse methodology, the project will produce new physically consistent high-resolution (300-m) data sets on ice-thicknesses from available radar measurements. Furthermore, the team will generate new remote sensing data sets on ice velocities and rates of elevation change. These will be used to constrain and validate the numerical models, and will also be valuable stand-alone data sets. This process will allow the numerical models to be constrained more tightly by data than has previously been possible. The resultant more robust model predictions of near-future impact of Thwaites Glacier on global sea levels can inform policy-relevant decision-making.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.

该项目有助于美国国家科学基金会（NSF）和英国联合发起的联合倡议。自然环境研究理事会（NERC）将大幅改善对南极洲西部Thwaites冰川造成的冰损失和海平面上升的十年期和长期预测。 在过去的三十年里，思韦茨冰川一直在加速和扩大。斯维特的解体速度有多快，或者它会多快找到一个新的稳定状态，已经成为西南极冰盖未来的一些最重要的问题，以及它在未来几十年到几个世纪甚至更长时间内对海平面上升的贡献。 该项目将依赖于三个独立的冰流数值模型，再加上一个海洋环流模型，以（1）提高我们对冰和底层基岩之间相互作用的理解，（2）分析冰川对外部变化的敏感程度，（3）评估可能导致斯威茨崩溃的过程，最重要的是，（4）预测斯威茨未来的冰损失。该项目将使用三个独立的冰盖模型：冰盖系统模型、Ua和STREAMICE，并与麻省理工学院大气环流模型的海洋环流模型相结合，通过提供基于一套耦合的冰-海模型的预测，评估模型预测的不确定性。该团队将首先专注于对产犊、冰损伤和基底光滑度等关键物理过程的表征，这些过程在以前的冰流建模工作中要么没有被包括，要么表现不佳。然后，该团队将量化不同拟议的外部变革驱动因素的相对作用（例如，海洋引起的冰架变薄、冰架钉扎点的丧失），并探索思韦茨冰川的稳定状况，目的是确定区分稳定和不稳定的地面线后退的内部阈值。 该项目将利用逆向方法，从现有的雷达测量数据中产生新的物理上一致的高分辨率（300米）冰厚数据集。 此外，该小组将生成关于冰速度和海拔变化率的新的遥感数据集。这些数据将用于约束和验证数值模型，也将是有价值的独立数据集。这一过程将使数值模型比以前更严格地受到数据的约束。 该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Model insights into bed control on retreat of Thwaites Glacier, West Antarctica

对西南极洲思韦茨冰川退缩过程中河床控制的模型分析

• DOI: 10.1017/jog.2023.13
• 发表时间: 2023
• 期刊: Journal of Glaciology
• 影响因子: 3.4
• 作者: Schwans, Emily;Parizek, Byron R.;Alley, Richard B.;Anandakrishnan, Sridhar;Morlighem, Mathieu M.
• 通讯作者: Morlighem, Mathieu M.

Limited Impact of Thwaites Ice Shelf on Future Ice Loss From Antarctica

思韦茨冰架对南极洲未来冰损失的影响有限

• DOI: 10.1029/2023gl102880
• 发表时间: 2023
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: Gudmundsson, G. H.;Barnes, J. M.;Goldberg, D. N.;Morlighem, M.
• 通讯作者: Morlighem, M.

Assessment of numerical schemes for transient, finite-element ice flow models using ISSM v4.18

使用 ISSM v4.18 评估瞬态有限元冰流模型的数值方案

• DOI: 10.5194/gmd-14-2545-2021
• 发表时间: 2021
• 期刊: Geoscientific Model Development
• 影响因子: 5.1
• 作者: dos Santos, Thiago Dias;Morlighem, Mathieu;Seroussi, Hélène
• 通讯作者: Seroussi, Hélène

Recrystallization of ice enhances the creep and vulnerability to fracture of ice shelves

冰的再结晶增强了冰架的蠕变和断裂脆弱性

• DOI: 10.1016/j.epsl.2021.117219
• 发表时间: 2021
• 期刊: Earth and Planetary Science Letters
• 影响因子: 5.3
• 作者: Ranganathan, Meghana;Minchew, Brent;Meyer, Colin R.;Peč, Matěj
• 通讯作者: Peč, Matěj

A new vertically integrated MOno-Layer Higher-Order (MOLHO) ice flow model

一种新的垂直集成单层高阶 (MOLHO) 冰流模型

• DOI: 10.5194/tc-16-179-2022
• 发表时间: 2022
• 期刊: The Cryosphere
• 作者: Dias dos Santos, Thiago;Morlighem, Mathieu;Brinkerhoff, Douglas
• 通讯作者: Brinkerhoff, Douglas