Collaborative Research: P2C2--Constraints on Last Interglacial and Late Holocene Global Mean Sea Level and Fingerprinting Polar Ice Mass Flux from Broadly Distributed Coastal Caves

合作研究：P2C2——对末次间冰期和晚全新世全球平均海平面的约束以及广泛分布的沿海洞穴的极地冰质量通量指纹识别

• 批准号: 2202698
• 负责人: Jerry Mitrovica
• 金额: $ 6.84万
• 依托单位: Harvard University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-01 至 2025-06-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2202698&HistoricalAwards=false
• 关键词: Collaborative; Research; P2C2; Constraints; Last

This project aims to advance the knowledge of global mean sea level (GMSL) and characterize the relative contribution of ice sheets and glaciers to GMSL variations. The researchers will use geological records preserved in cave deposits to reconstruct the GMSL history over the last 130.000 years from multiple locations (Mediterranean Sea, Yucatan Peninsula, Philippine Sea), and to study sea-level high stands during past warm climates. With over one third of the world’s population living within coastline regions, assessing the regional vulnerability to future-sea level rise is of societal relevance and requires an understanding of the magnitude, rate, and drivers of past sea level fluctuations to put current trends in context. This will be achieved by direct sea level estimates provided by coastline mineralogical records, namely phreatic overgrowth on speleothems which form at sea level on partly submerged caves.Phreatic overgrowths on speleothems (POS) are precise and accurate indicators of local sea level changes during critical periods of the ice age, including the Mid-Pliocene Warm period, the Last Interglacial (LIG) and the Late Holocene. This project aims to analyze existing POS archives and to expand this archive to include several promising cave sites. The scientific goals are encapsulated in several core research questions: 1) What is the temporal variability of GMSL from the LIG to the Late Holocene and what is the phasing between peak GMSL and the initiation of global scale warming; 2) What are the relative contributions of the major polar ice sheets to this variability and is there evidence of hemispheric teleconnections?; and 3) to what extent is the GMSL rise and acceleration anomalous relative to the record of GMSL across the Late Holocene? The researchers will develop a near continuous GMSL curve for climate warm intervals derived from high temporally and vertically well resolved POS observations linked to state of the art statistical and geophysical modelling. The observations include U-series chronologies, high-resolution stable isotope analyses of C and O, and mineralogical and petrographical analyses to constrain timing and duration of peak sea-level high stands. Additionally, numerical simulations of Glacial Isostatic Adjustment (GIA) will be used to correct GMSL record from the impact of GIA. The potential Broader Impacts (include a greater knowledge and a better understanding of the magnitude and drivers of sea level rise. This has direct implication for different scientific communities investigating key relationships between sea level, ice sheets, Earth’s climate, and properties of the solid earth. Further, the newly developed knowledge will be of a broad societal relevance as it will potentially benefit coastal communities, stakeholders, and policy makers. This project will provide education and research training for graduate and undergraduate students at the universities of South Florida, New Mexico and Harvard who will be involved in many aspects of the interdisciplinary research. Additionally, the results of this research will be communicated through teaching at the various project institutions. The researchers will disseminate the project findings with the relevant scientific communities via peer-reviewed publication and presentation at national and international conferences. The research finding will be also disseminated to the broader public through public presentations, popular science articles and media coverage. Educational material will be developed for outreach activities at the studied caves, including underwater images and videos. The data collected during this project will be made publicly accessible.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.

该项目旨在增进对全球平均海平面 (GMSL) 的了解，并描述冰盖和冰川对 GMSL 变化的相对贡献。研究人员将利用洞穴沉积物中保存的地质记录来重建 GMSL 过去 13 万年的历史。多个地点（地中海、尤卡坦半岛、菲律宾海），并研究过去温暖气候期间的海平面高位，评估该区域。未来海平面上升的脆弱性具有社会相关性，需要了解过去海平面波动的幅度、速率和驱动因素，以将当前趋势纳入背景，这将通过海岸线矿物学记录提供的直接海平面估计来实现。即在海平面部分淹没的洞穴中形成的洞穴生物过度生长。洞穴生物过度生长 (POS) 是冰河时期关键时期当地海平面变化的精确指标，包括上新世中期温暖期、末次间冰期 (LIG) 和全新世晚期 该项目旨在分析现有的 POS 档案并扩展该档案以包括几个有前景的洞穴遗址。科学目标包含在几个核心研究问题中。从 LIG 到全新世晚期 GMSL 的时间变化是什么，以及 GMSL 峰值和全球范围变暖开始之间的阶段是什么 2) 主要极地冰盖对这种变化的相对贡献是什么；是否有半球遥相关的证据？；3）相对于全新世晚期的 GMSL 记录，GMSL 的上升和加速有多大程度的异常？与最先进的统计和地球物理建模相关的垂直分辨率良好的 POS 观测，这些观测包括 U 系列年代学、C 和 O 的高分辨率稳定同位素分析以及矿物学和地球物理模型。此外，冰川等静压调整 (GIA) 的数值模拟将用于纠正 GMSL 记录免受 GIA 潜在更广泛影响的影响。更好地了解海平面上升的幅度和驱动因素，这对于研究海平面、冰盖、地球气候和固体地球特性之间的关键关系的不同科学界具有直接意义。广阔该项目将为南佛罗里达大学、新墨西哥大学和哈佛大学的研究生和本科生提供教育和研究培训，他们将参与跨学科的许多方面。此外，这项研究的结果将通过各个项目机构的教学进行交流，研究人员将通过同行评审的出版物和在国家和国际会议上的演讲来传播项目研究结果。还通过公众号向更广泛的公众传播将为所研究的洞穴的外展活动开发教育材料，包括水下图像和视频。该奖项是国家科学基金会的法定使命，被认为是值得的。通过使用基金会的智力优势和更广泛的影响审查标准进行评估来获得支持。