NSF-NERC: Geological History Constraints on the Magnitude of Grounding Line Retreat in the Thwaites Glacier System

NSF-NERC：地质历史对思韦茨冰川系统接地线后退幅度的限制

基本信息

批准号：
2317097
负责人：
Ryan Venturelli
金额：
$ 105.16万
依托单位：
Colorado School of Mines
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
2023
资助国家：
美国
起止时间：
2023-03-01 至 2025-03-31
项目状态：
未结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2317097&HistoricalAwards=false
关键词：
NSF NERC Geological History Constraints

项目摘要

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. The Thwaites Glacier system dominates the contribution to sea-level rise from Antarctica. Predicting how this system will evolve in coming decades, and thereby its likely contribution to sea level, requires detailed understanding of how it has responded to changes in climate and oceanographic conditions in the past. This project will provide a record of regional sea-level change by establishing chronologies for raised marine beaches as well as the timing and duration of periods of retreat of Thwaites Glacier during the past 10,000 years by sampling and dating bedrock presently covered by Thwaites Glacier via subglacial drilling. Together with climatic and oceanographic conditions from other records, these will provide boundary conditions for past-to-present model simulations as well as those used to predict future glacier changes under a range of climate scenarios. Specifically, the project will test the hypothesis--implied by existing geological evidence from the region--that present rapid retreat of the Thwaites Glacier system is reversible. The team aims to utilize two approaches: 1. To reconstruct relative sea level during the Holocene, it will map and date raised marine and shoreline deposits throughout Pine Island Bay. Chronological constraints on sea-level change will be provided by radiocarbon dating of organic material in landforms and sediments that are genetically related to past sea level, such as shell fragments, bones of marine fauna, and penguin guano. 2. To obtain geological evidence for past episodes of grounding-line retreat, the team will apply cosmogenic-nuclide exposure-dating of subglacial bedrock. Using drill systems recently developed for subglacial bedrock recovery, the team will obtain subglacial bedrock from sites where ice thickness is dynamically linked to grounding-line position in the Thwaites system (specifically in the Hudson Mountains, and near Mount Murphy). Observation of significant cosmogenic-nuclide concentrations--the team will primarily measure Beryllium-10 and in situ Carbon-14--in these samples would provide direct, unambiguous evidence for past episodes of thinning linked to grounding-line retreat as well as constraints on their timing and duration.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.

该项目为美国国家科学基金会 (NSF) 和英国自然环境研究委员会 (NERC) 发起的联合倡议做出了贡献，该倡议旨在大幅改进对源自西部思韦茨冰川的冰损失和海平面上升的十年和长期预测南极洲。思韦茨冰川系统对南极洲海平面上升起着主导作用。预测该系统在未来几十年将如何演变，及其对海平面可能的贡献，需要详细了解它如何应对过去的气候和海洋条件变化。该项目将通过对目前被思韦茨冰川覆盖的基岩进行采样和年代测定，建立凸起海滩的年表，以及过去一万年思韦茨冰川退缩的时间和持续时间，从而提供区域海平面变化的记录。钻孔。与其他记录中的气候和海洋条件一起，这些将为过去至今的模型模拟以及用于预测一系列气候情景下未来冰川变化的边界条件提供边界条件。具体来说，该项目将测试该地区现有地质证据所暗示的假设，即思韦茨冰川系统目前的快速退缩是可逆的。该团队的目标是利用两种方法： 1. 为了重建全新世期间的相对海平面，它将绘制整个松岛湾凸起的海洋和海岸线沉积物的地图和日期。海平面变化的时间限制将通过对与过去海平面遗传相关的地貌和沉积物中的有机物质进行放射性碳测年来提供，例如贝壳碎片、海洋动物的骨头和企鹅鸟粪。 2. 为了获得过去接地线撤退事件的地质证据，该团队将应用冰下基岩的宇宙成因核素暴露测年法。使用最近开发的用于冰下基岩恢复的钻探系统，该团队将从冰厚度与思韦茨系统中的接地线位置动态相关的地点（特别是在哈德逊山脉和墨菲山附近）获取冰下基岩。对这些样本中显着宇宙成因核素浓度的观察（该团队将主要测量铍 10 和原位碳 14）将为过去与接地线撤退相关的变薄事件以及对地球的限制提供直接、明确的证据。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力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

期刊论文数量（6）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Geological insights from the newly discovered granite of Sif Island between Thwaites and Pine Island glaciers

思韦茨冰川和松岛冰川之间新发现的锡夫岛花岗岩的地质见解

DOI：
10.1017/s0954102023000287
发表时间：
2024-02
期刊：
Antarctic Science
影响因子：
1.6
作者：
Marschalek, James W.;Thomson, Stuart N.;Hillenbrand, Claus;Vermeesch, Pieter;Siddoway, Christine;Carter, Andrew;Nichols, Keir;Rood, Dylan H.;Venturelli, Ryan A.;Hammond, Samantha J.;et al
通讯作者：
et al

Offshore-onshore record of Last Glacial Maximum–to–present grounding line retreat at Pine Island Glacier, Antarctica

南极洲松岛冰川末次盛冰期至目前接地线退缩的近海-陆上记录

DOI：
10.1130/g51326.1
发表时间：
2023-08
期刊：
Geology
影响因子：
5.8
作者：
Nichols, Keir A.;Rood, Dylan H.;Venturelli, Ryan A.;Balco, Greg;Adams, Jonathan R.;Guillaume, Louise;Campbell, Seth;Goehring, Brent M.;Hall, Brenda L.;Wilcken, Klaus;et al
通讯作者：
et al

Relative sea-level data preclude major late Holocene ice-mass change in Pine Island Bay

相对海平面数据排除了松岛湾全新世晚期冰块的重大变化

DOI：
10.1038/s41561-022-00961-y
发表时间：
2022-06
期刊：
Nature Geoscience
影响因子：
18.3
作者：
Braddock, Scott;Hall, Brenda L.;Johnson, Joanne S.;Balco, Greg;Spoth, Meghan;Whitehouse, Pippa L.;Campbell, Seth;Goehring, Brent M.;Rood, Dylan H.;Woodward, John
通讯作者：
Woodward, John

Reversible ice sheet thinning in the Amundsen Sea Embayment during the Late Holocene

全新世晚期阿蒙森海湾冰盖可逆减薄

DOI：
发表时间：
2023-04
期刊：
The Cryosphere
影响因子：
0
作者：
Balco, G.;Brown, N.;Nichols, K.;Venturelli, R.A.;Adams, J.R.;Braddock, S.;Campbell, S.;Goehring, B.;Johnson, J.S.;Rood, D.H.;et al
通讯作者：
et al

Lessons learned from shallow subglacial bedrock drilling campaigns in Antarctica

从南极洲浅层冰下基岩钻探活动中汲取的经验教训

DOI：
10.1017/aog.2024.12
发表时间：
2024-03
期刊：
Annals of Glaciology
影响因子：
2.9
作者：
Braddock, Scott;Venturelli, Ryan A.;Nichols, Keir;Moravec, Elliot;Boeckmann, Grant V.;Campbell, Seth;Balco, Greg;Ackert, Robert;Small, David;Johnson, Joanne S.;et al
通讯作者：
et al