Collaborative Research: Reconstructions of Southern Caribbean Climate Variability using Contemporaneous and Co-Located Corals and Speleothems

合作研究：利用同期和同处的珊瑚和洞穴化石重建南加勒比气候变化

• 批准号: 2303299
• 负责人: Warren Sharp
• 金额: $ 13.84万
• 依托单位: Berkeley Geochronology Center
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2303299&HistoricalAwards=false
• 关键词: Collaborative; Research; Reconstructions; Southern; Caribbean

Historical and ancient climate data from paleoclimate proxy records can provide the long-term climate context necessary to support coastal Caribbean communities in preparing for, adapting to, and/or mitigating the numerous impacts of anthropogenic climate change. This project will study coral and speleothem carbonates from reef ecosystems and cave environments on the island of Curaçao in the arid Southern Caribbean. Geochemical analyses and dating of these carbonates will be used to generate records of local temperature and aridity that span the interval as Earth warmed from the Last Glacial Maximum (~20 thousand years ago) to present. Coupling these geochemical analyses with monitoring of modern reef and cave environments and numerical modeling will help determine the extent to which Caribbean Sea climates have varied in the past and the role that they play in mediating global climate on seasonal to glacial-interglacial timescales. The proposed research presents a unique opportunity to develop and apply integrated approaches to understand coeval archives of terrestrial and marine climate variability at a single, relatively understudied location. Broader impacts of this research include the dissemination of major findings through community-influenced geoscience curricula development and tiered mentorship opportunities for students from the K-12 through postdoctoral levels. For example, the research will support research exchange opportunities for University of Curaçao students through a targeted cross-institutional partnership with the Caribbean Research and Management of Biodiversity (CARMABI) foundation, in which undergraduate students will work on the Georgia Tech and Vanderbilt campuses where they will be integrated into a diverse, multi-institutional team of PIs, postdocs, and graduate and undergraduate students.Anthropogenic climate change in the Caribbean Sea is projected to extend seasonal warm periods, increase the frequency and intensity of heavy rainfall events, and increase periods of prolonged drought. Paleoclimate records from speleothem and coral carbonates from the wet tropical Northern and Western Caribbean have provided context for these projections by illustrating the relevant climate drivers and teleconnections over the past several thousand years. However, equally extensive and informative records are notably absent from the arid Southern Caribbean. This project will develop precisely dated, co-located coral and speleothem proxy temperature and hydroclimate records from Curaçao, synthesize these records with other regional and global proxies, and make transformative progress in the understanding of how carbonate minerals in terrestrial and marine ecosystems record past environmental change in this region. Trace element-to-calcium ratios (i.e. Sr/Ca, Mg/Ca, Ba/Ca, etc.) and traditional stable isotopes (δ18O, δ13C, etc.) from actively-precipitating stalagmites, drip waters, modern coral skeletons, and seawater will be further integrated with proxy system models and instrumental data to fingerprint the dominant drivers of terrestrial and marine climate on seasonal to decadal timescales. This understanding will be applied to jointly interpret speleothem and coral proxy records of hydroclimate and SST and develop a comprehensive picture of seasonal to millennial climate evolution since the last deglaciation. This work includes the development of optimal U-Th dating techniques to jointly analyze speleothem and coral carbonates, active seawater and cave monitoring, and the development and application of novel geochemical proxies, including new methods for the analysis of the calcium isotope quantitative precipitation proxy in speleothems via collision cell multi-collector ICP-MS. This award is co-funded by the Division of Earth Sciences and Division of Atmospheric and Geospace Sciences by way of the Paleo Perspectives on Present and Projected Climate Program, as well as the Division of Earth Sciences funds for support of projects that increase research capabilities, capacity and infrastructure at a wide variety of institution types, as outlined in the GEO EMBRACE DCL.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.

来自古气候代用记录的历史和古代气候数据可以提供支持加勒比沿海社区准备、适应和/或减轻人为气候变化的众多影响所需的长期气候背景。该项目将研究南加勒比干旱地区库拉索岛珊瑚礁生态系统和洞穴环境中的珊瑚和洞穴碳酸盐。这些碳酸盐的地球化学分析和测年将用于生成当地温度和干旱的记录，这些记录跨越了地球从末次冰期最大期（约2万年前）到现在变暖的时间间隔。将这些地球化学分析与对现代珊瑚礁和洞穴环境的监测以及数值模拟相结合，将有助于确定加勒比海气候在过去的变化程度，以及它们在调节季节性至冰期-间冰期时间尺度上的全球气候方面所发挥的作用。拟议的研究提供了一个独特的机会，开发和应用综合方法，以了解在一个单一的，相对欠研究的位置的陆地和海洋气候变化的同时代档案。这项研究的更广泛的影响包括通过社区影响的地球科学课程开发和分层导师的机会，从K-12到博士后水平的学生的主要研究结果的传播。例如，该研究将通过与加勒比生物多样性研究和管理（CARMABI）基金会的有针对性的跨机构合作伙伴关系，支持库拉索岛大学学生的研究交流机会，其中本科生将在格鲁吉亚理工学院和范德比尔特校区工作，他们将融入一个多元化的多机构PI团队，博士后，加勒比海的人为气候变化预计将延长季节性温暖期，增加暴雨事件的频率和强度，并增加长期干旱期。来自潮湿的热带北方和西加勒比海的洞穴沉积物和珊瑚碳酸盐的古气候记录通过说明过去几千年的相关气候驱动因素和遥相关为这些预测提供了背景。然而，同样广泛和翔实的记录明显缺乏干旱的南加勒比海。该项目将开发库拉索岛精确定年、共址的珊瑚和洞穴沉积物代用温度和水文气候记录，将这些记录与其他区域和全球代用资料综合，并在了解陆地和海洋生态系统中的碳酸盐矿物如何记录该区域过去的环境变化方面取得变革性进展。微量元素与钙的比值（即Sr/Ca、Mg/Ca、Ba/Ca等）和传统的稳定同位素（δ 18 O、δ 13 C等）来自活跃沉淀石笋、滴水沃茨、现代珊瑚骨骼和海水的数据将进一步与代理系统模型和仪器数据相结合，以确定季节至十年时间尺度上陆地和海洋气候的主要驱动因素。这种理解将被应用于共同解释洞穴和珊瑚水文气候和SST的代用记录，并制定一个全面的图片季节到千年的气候演变，因为最后一次冰消期。这项工作包括开发最佳的U-Th测年技术，以联合分析洞穴沉积物和珊瑚碳酸盐，活动海水和洞穴监测，以及开发和应用新的地球化学代理，包括通过碰撞池多收集器ICP-MS分析洞穴沉积物中钙同位素定量沉淀代用品的新方法。由地球科学司和大气与地球空间科学司通过“古气候展望当前和预测气候方案”提供资金，以及地球科学司为支持提高研究能力的项目提供资金，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。