AGS-PRF: Resolving High-Resolution Paleoclimate Variability in Subarctic Canada across the Mid Pleistocene Transition and Interglacial Periods of the Last 1.5 Ma

基于洞穴群的古气候重建提供了一些分辨率最高的陆地气候记录。这项提议旨在利用一组罕见的生长缓慢的亚北极洞穴群来描述加拿大亚北极大陆中部过去间冰期更新世的气候变异性。研究人员将结合一套分析工具来研究这些洞穴问题，包括新的地质年代学技术(U-Pb)、微观分析技术(二次离子质谱仪，SIMS)和成像(共焦荧光激光显微镜，CFLM)，以重建北美高纬度地区的古气候。这些新的记录将调查高纬度气候在过去的间冰期是否或多或少发生了变化，这些间冰期甚至比现在更温暖，例如过去800ka的最温暖的间冰期。该项目的潜在成果将包括解决过去150万年间不同间冰期温度变化的广泛记录，以及提供高频(亚年度到亚十年)水气候变化的快照。潜在的更广泛的影响有两个：(1)博士后的专业发展，(2)社区参与。这位博士后研究人员将在新的地质年代学方法方面获得第一手经验，以确定美国仅有的几个实验室之一的洞穴记录的年代，该实验室是为洞穴的U-Pb测年而建立的。此外，博士后研究员将通过直接工作以及与本科生和研究生的互动获得指导经验。该项目的研究成果将通过建立一个双向合作网络与西北地区(加拿大)的当地社区分享，该网络将：1)让奥罗拉学院(西北地区唯一的高等教育机构)的学生和教职员工了解西北地区洞穴中正在进行的气候研究项目；2)向博士后研究员和项目同事讲授北极变暖对当地土著社区的影响。作为这些外联工作的一部分，将向当地市政当局，特别是奥罗拉学院分发教育和互动展示材料。这一推广计划的目标之一将是在地球科学会议(例如AGU)上向气候科学家分享从生活在西北地区社区的人们那里学到的东西，以更好地开展科学交流活动，并传达气候科学研究的更广泛的社会影响。该奖项反映了NSF的法定使命，并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，被认为值得支持。

Speleothem-based paleoclimate reconstructions provide some of the highest-resolution terrestrial climate records. This proposal aims to characterize past interglacial Pleistocene climate variability in mid-continental, subarctic Canada using a rare collection of slow-growing subarctic speleothems. The researcher will combine a set of analytical tools to these speleothems including, novel geochronological techniques (U-Pb), micro-analytical technique (secondary ion mass spectrometry, SIMS), and imaging (confocal fluorescent laser microscopy, CFLM) to reconstruct high-latitude North American paleoclimate. These new records will investigate whether high-latitude climates were more or less variable during past interglacial periods that were even warmer than today, such as the warmest interglacial period of the last 800 ka. The potential results of this project will include resolving broad records of temperature changes across different interglacial stages of the last 1.5 Million years, as well as providing snapshots of high-frequency (sub-annual to sub-decadal) hydroclimate variability.The potential Broader Impacts are twofold: (1) professional development of the postdoctoral fellow, and (2) community engagement. The postdoctoral researcher will gain first-hand experience in novel geochronology methods to date speleothems records in one of the only labs in the United States that is set up for U-Pb dating of speleothems. Additionally, the postdoctoral fellow will gain mentoring experience through direct work and interaction with undergraduate and graduate students. The research finding of this project will be shared with local communities in Northwest Territories (Canada) by setting up a two-way collaborative network that will, 1) Expose and engage students and staff at Aurora College (the only post-secondary institution within the Northwest Territories) about active climate research projects at Northwest Territory caves, and 2) Teach the postdoctoral fellow and project colleagues about the impact Arctic warming has on local indigenous communities. As part of these outreach efforts, educational and interactive display materials will be distributed to local municipalities, specifically Aurora College. One of the goals of this outreach plan will be to share what is learned from the people living in the communities of the Northwest Territories to climate scientists at Geoscience meetings (e.g. AGU) to better science communication initiatives and relay the broader societal impact of climate science research.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.