EAR-PF: Reconstructing late Holocene hydroclimatic variability in western Central America using multi-proxy analyses of lacustrine sediments

EAR-PF：利用湖泊沉积物的多代理分析重建中美洲西部全新世晚期水文气候变化

• 批准号: 2204484
• 负责人: Derek Gibson
• 金额: $ 18万
• 依托单位: Gibson, Derek K
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-10-01 至 2024-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2204484&HistoricalAwards=false
• 关键词: EAR; PF; Reconstructing; late; Holocene

Dr. Derek Gibson has been awarded an NSF EAR Postdoctoral Fellowship to carry out research and education plans at Missouri University of Science and Technology under the mentorship of Dr. Jonathan Obrist-Farmer. Hydroclimate extremes, particularly droughts, have resulted in an unprecedented increase in climate refugees from Central America over the past decade, creating a humanitarian, economic, and national security crisis. Current climate models predict that Central American precipitation will further decrease by the end of the century. However, the models used to predict such changes rely on records of past climate change and, at present, regional data that reflect how Central American precipitation changed in the past are sparse. This project will use sediment cores collected from Guatemala and southern Mexico to produce evidence of past changes in Central American precipitation that spans the past 2,000 years. In turn, these new records will improve current predictive models of Central American precipitation, which is critical to building a climate-resilient future in Central America and reducing the extent of climate-driven human migration over the upcoming decades. In addition to producing new climate data, K-12 partnerships will extend the impact of this research by educating the next generation of scientists on the mechanisms and impacts of climate change. Educational activities and international collaborations will involve students from elementary to graduate school and provide opportunities for historically underserved students to contribute to solving one of the major climate science questions of the 21st century.Predictable precipitation patterns are critical to the food security and economic stability of Central America. However, inter-model heterogeneity among current climate models, due in part to a paucity of high-resolution and local-scale paleoclimate records that span the late Holocene, make reliable projections of future precipitation difficult. The proposed research will utilize sediment cores from six watersheds located across Guatemala and the Yucatán Peninsula in order to produce multi-proxy reconstructions of local-scale hydroclimatic variability within the context of the synoptic-scale climate changes that occurred during the Medieval Climate Anomaly, Little Ice Age, and Current Warm Period. The proposed field sites are situated such that sediment cores collected from these sites can be used to investigate variability through time in the relative influences of the Inter-tropical Convergence Zone, Caribbean Low-Level Jet, El Niño Southern Oscillation, and topography. Specifically, stratigraphic variability of δ2H in leaf-wax long chain (n-C27, n-C29, n-C31) n-alkanes preserved in the sediment cores will be used as a proxy for regional hydroclimatic variability, while the δ2H of short chain (n-C21, n C23) n-alkanes will be used to reconstruct precipitation/evaporation balance at the local (water column to watershed) scale. These data will be a critical component of predictive models used in the Central American climate resilience and adaptation plans that must be implemented before climate-driven human migration leads to further suffering.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.

德里克·吉布森 (Derek Gibson) 博士获得了 NSF EAR 博士后奖学金，在乔纳森·奥布里斯特·法默 (Jonathan Obrist-Farmer) 博士的指导下，在密苏里科技大学开展研究和教育计划。 极端水文气候，特别是干旱，导致了前所未有的增加。过去十年中美洲的气候难民造成了人道主义、经济和国家安全危机。目前的气候模型预测，到本世纪末，中美洲的降水量将进一步减少。然而，用于预测此类变化的模型依赖于。过去气候变化的记录目前，反映中美洲降水过去变化情况的区域数据很少，该项目将利用从危地马拉和墨西哥南部收集的沉积物岩心来提供过去 2,000 年来中美洲降水变化的证据。反过来，这些新记录将改进当前的中美洲降水预测模型，除了产生新的气候数据之外，这对于在中美洲建立气候适应能力的未来和减少未来几十年气候驱动的人类迁徙的程度至关重要。 , K-12伙伴关系将通过教育下一代科学家了解气候变化的机制和影响来扩大这项研究的影响。教育活动和国际合作将涉及从小学到研究生的学生，并为历史上服务不足的学生提供机会，为解决其中一个问题做出贡献。 21 世纪的主要气候科学问题。可预测的降水模式对于中美洲的粮食安全和经济稳定至关重要。然而，当前气候模型之间的模型间异质性部分归因于缺乏高分辨率和本地模型。规模古气候跨越全新世晚期的记录，使得对未来降水量的可靠预测变得困难。拟议的研究将利用来自危地马拉和尤卡坦半岛六个流域的沉积岩芯，以便在中世纪气候异常、小冰期和当前温暖期期间发生的天气尺度气候变化 拟议的现场地点的位置使得从这些地点收集的沉积物岩心可用于研究随时间变化的变化。热带辐合带、加勒比低空急流、厄尔尼诺南方涛动和地形的相对影响，特别是叶蜡长链（n-C27、n-C29、n-C31）中 δ2H 的地层变化。 ）沉积物岩心中保存的正构烷烃将用作区域水文气候变化的代表，而短链（n-C21、n C23）的δ2H正烷烃将用于重建当地（水体到流域）规模的降水/蒸发平衡，这些数据将成为中美洲气候恢复力和适应计划中使用的预测模型的关键组成部分，这些计划必须在气候变化之前实施。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。