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）博士在乔纳森·奥布里斯特·弗里姆（Jonathan Obriist-Farmer）的心态下被授予NSF耳朵博士后奖学金，以在密苏里科学技术大学的心理下执行研究和教育计划。在过去的十年中，氢气气候极端，特别是干旱，导致中美洲气候难民的前所未有，造成了人道主义，经济和国家安全危机。当前的气候模型预测，到本世纪末，中美洲的精度将进一步降低。但是，用于预测此类变化的模型取决于过去气候变化的记录，并且目前反映了中美洲精确度如何变化的区域数据稀疏。该项目将使用从危地马拉和墨西哥南部收集的沉积物核心，以产生过去2000年中中美洲精确性变化的证据。反过来，这些新记录将改善中美洲准确性的当前预测模型，这对于在中美洲建立气候韧性的未来至关重要，并在未来几十年中降低了气候驱动的人类移民的程度。除了生成新的气候数据外，K-12合作伙伴关系还将通过教育下一代科学家对气候变化的机制和影响来扩展这项研究的影响。教育活动和国际合作将涉及从小学到研究生院的学生，并为历史上服务不足的学生提供有助于解决21世纪主要气候科学问题之一的机会。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。但是，当前气候模型之间的模型间异质性部分是由于跨越最新全新世的高分辨率和局部规模的古气候记录，这使得未来降水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物核心，以便在概要尺度的气候变化中产生局部规模的氢化气候变化的多型氢化气候变化，这是中世纪气候变化在中世纪气候性动脉粥样硬化期间发生的，冰冰年龄，冰期年龄，没有冰期的冰期和当前温暖的时期。所提出的田间位点的位置使得从这些位点收集的沉积物芯可用于调查热带间收敛区，加勒比海低水平喷气机，厄尔尼诺尼诺南部振荡和地形的相对影响的变异性。具体而言，叶波长链中Δ2H（N-C27，N-C29，N-C31）N-烷烃中保存在沉积物核心中的N-Alkanes的地层变异将被用作局部水溶液变异性的代理，而短链的Δ2H将用于短链（N-C21，N-C23）n-c23 n-c23）精确的水平。 规模。这些数据将是中美洲气候弹性和适应计划中使用的预测模型的关键组成部分，在气候驱动的人类移民带来进一步的痛苦之前，必须实施，这一奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子优点和更广泛的影响审查标准来通过评估来通过评估来支持的。