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: 2202712
• 负责人: Victor Polyak
• 金额: $ 34.85万
• 依托单位: University of New Mexico
• 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=2202712&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.

该项目旨在提高对全球平均海平面（GMSL）的认识，并描述冰盖和冰川对GMSL变化的相对贡献。 研究人员将利用保存在洞穴沉积物中的地质记录，从多个地点（地中海，尤卡坦半岛，菲律宾海）重建过去13万年的GMSL历史，并研究过去温暖气候期间的海平面高。 世界上三分之一以上的人口生活在沿海地区，评估该区域对未来海平面上升的脆弱性具有社会意义，需要了解过去海平面波动的幅度、速度和驱动因素，以了解当前的趋势。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，即在海平面上形成于部分淹没的洞穴上的洞穴积土上的潜水过度生长（POS）是冰河时代关键时期（包括上新世中期温暖期，末次间冰期（LIG）和全新世晚期）当地海平面变化的精确和准确的指标。该项目旨在分析现有的POS档案，并扩大这一档案，包括几个有前途的洞穴遗址。这些科学目标包含在几个核心研究问题中：1）从LIG到晚全新世GMSL的时间变化是什么？GMSL峰值和全球变暖开始之间的相位是什么？2）主要的极地冰盖对这种变化的相对贡献是什么？（3）相对于晚全新世的GMSL记录，GMSL的上升和加速度异常程度如何？研究人员将开发一个接近连续的GMSL曲线，用于气候变暖间隔，该曲线来自与最先进的统计和地球物理建模相关的高时间和垂直分辨率POS观测。观测包括U系列年表、C和O的高分辨率稳定同位素分析以及矿物学和岩相学分析，以限制峰值海平面高站的时间和持续时间。此外，还将利用冰川均衡调整（GIA）的数值模拟来校正GIA影响下的GMSL记录。潜在的更广泛的影响（包括对海平面上升的幅度和驱动因素有更多的了解和更好的理解。这对不同的科学团体调查海平面，冰盖，地球气候和固体地球属性之间的关键关系有直接的影响。此外，新开发的知识将具有广泛的社会相关性，因为它可能使沿海社区，利益攸关方和决策者受益。该项目将为南佛罗里达、新墨西哥州和哈佛大学的研究生和本科生提供教育和研究培训，他们将参与跨学科研究的许多方面。此外，这项研究的结果将通过在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介绍，向相关科学界传播项目成果。研究结果还将通过公开演讲、科普文章和媒体报道向更广泛的公众传播。将为所研究洞穴的外联活动编制教育材料，包括水下图像和录像。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。