Doctoral Dissertation Research: Tracking Donna Across the Northern Caribbean: Developing a Modern Analog Methodology for Paleotempestology

博士论文研究：在北加勒比海追踪唐娜：为古风暴学开发现代模拟方法

• 批准号: 0623287
• 负责人: Kam-biu Liu
• 金额: $ 1.19万
• 依托单位: Louisiana State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-08-01 至 2008-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0623287&HistoricalAwards=false
• 关键词: Doctoral; Dissertation; Research; Tracking; Donna; Doctoral; Dissertation; Research; Tracking; Donna

The highly destructive hurricane season of 2005 intensified debate regarding the degree to which the number and intensity of hurricane and other severe storms were related to possibly significant changes in local, regional, and global climatic regimes. Attempts to study historical trends have been hampered by the fact that instrument-based climate records have existed only in relatively recent time periods. Paleotempestology can look to the proxy record to overcome the limitations of the instrumental record and can help to identify hurricane frequency changes that are not evident in the modern record. This doctoral dissertation research project will establish the first extensive modern analog study for paleotempestology by quantitatively assessing and characterizing the geomorphic and sedimentological impacts of Hurricane Donna across three northern Caribbean islands via the stratigraphic analysis of coastal lake sediment cores. Hurricane Donna directly struck the Caribbean island nations of Barbuda, Anguilla, and Acklins Island (Bahamas) as a severe category 4 hurricane in 1960 before making landfall in southern Florida and ravaging the U.S. Atlantic coast, causing tremendous destruction and casualties along its path. This study will test the hypothesis that Donna caused an overwash event in each of the three Caribbean islands, which would have left a detectable record in the form of overwash sand layers in the sediments of coastal back-barrier lakes. The stratigraphic record of Donna will be compared with those of other recent hurricanes of known intensities that also impacted the islands, so that the modern relationship between hurricane intensity and proxy signal strength (e.g., sand layer thickness) can be established. Using multiple geological and biological proxies in concert with radio-isotopic dating (14C and 137Cs), the stratigraphic signature of Hurricane Donna will be identified and used to calibrate the proxy records of prehistoric hurricane strikes in an effort to reconstruct a late-Holocene history of hurricane activities for the northern Caribbean. The reconstruction of a long-term hurricane history for the northern Caribbean will allow, in conjunction with other ongoing paleotempestological studies in other parts of the Caribbean, for the interpretation of basin-wide shifts in hurricane patterns that in turn can be used to decipher the forcing mechanisms behind them. This project is significant as it contributes to the young science of paleotempestology by establishing a comprehensive modern analog methodology that is essential to the calibration and interpretation of the proxy records. This project will also establish the first proxy records of prehistoric hurricane strikes for the northern Caribbean, thereby filling a large gap in the current knowledge and data network for Atlantic paleohurricanes. These new proxy records from the northern Caribbean will be vital for testing the Bermuda High Hypothesis, which is a cornerstone in the burgeoning field of paleotempestology. There are many practical applications for this study and they have far reaching relevance to the societies of the Caribbean region. There is a pressing need to understand the spatial and temporal variability of hurricane activity in the Caribbean and the climate mechanisms responsible for this variability. This study will produce long-term proxy records that are necessary for the calculation of hurricane return periods and annual landfall probabilities for the northern Caribbean region. These data have great societal value and can be used by local government officials in risk assessment and mitigation planning. Involvement of local researchers and school students in fieldwork will also contribute to science education and capacity building in these Caribbean island nations.

2005年，高度破坏性的飓风季节加剧了关于飓风和其他严重风暴的数量和强度与可能发生的重大变化有关的地方，地区和全球气候制度的重大变化的辩论。 基于仪器的气候记录仅在相对较新的时期内才存在，这一事实阻碍了研究历史趋势的尝试。 古植物学可以看待代理记录，以克服仪器记录的局限性，并有助于确定现代记录中不明显的飓风变化。 该博士学位论文研究项目将通过定量评估和表征飓风Donna在三个加勒比海北部岛屿上通过沿海湖泊沉积物核心的地层分析进行定量评估和表征飓风Donna的地貌和沉积学影响，从而建立首次为古植物学的现代模拟研究。 唐娜飓风直接袭击了巴布达，安圭拉和阿克林斯岛（巴哈马）的加勒比岛国家，在1960年成为严重的4级飓风，然后在佛罗里达州南部登陆并破坏了美国大西洋海岸，造成了巨大的毁灭和沿途造成的伤亡。 这项研究将检验以下假设：唐纳在三个加勒比海群岛中的每个群岛中的每一个都造成了一次夸大事件，该事件将在沿海后栏湖沉积物中以覆盖砂层的形式留下可检测的记录。 Donna的地层记录将与其他近期飓风的飓风相提并论，这些强度也影响了岛屿，以便可以建立飓风强度与代理信号强度（例如，砂层厚度）之间的现代关系。 将使用多个地质和生物学代理与放射性异位约会（14C和137C）共同确定飓风Donna的地层签名，并用于校准史前飓风罢工的代理记录，以期重建北部加勒巴巴飓风活动的晚期历史。 加勒比海北部的长期飓风历史的重建将允许与加勒比海其他地区的其他正在进行的古植物学研究结合使用，以解释飓风模式中盆地范围内的变化，这反过来又可以破坏其背后的强迫机制。 该项目非常重要，因为它通过建立一种全面的现代模拟方法来为年轻的古植物科学做出了贡献，该方法对代理记录的校准和解释至关重要。 该项目还将为北加勒比海地区的史前飓风袭击建立第一批代理记录，从而填补了大西洋古纯洁的当前知识和数据网络的巨大空白。 这些来自北加勒比海的新代理记录对于测试百慕大高假设至关重要，这是古植物迅速发展领域的基石。 这项研究有许多实际应用，它们与加勒比地区的社会具有很大的相关性。 迫切需要了解加勒比海飓风活动的空间和时间变化以及使这种变异性的气候机制。 这项研究将产生长期的代理记录，这是计算北加勒比地区飓风返回期和年度登陆概率所必需的。 这些数据具有巨大的社会价值，可以在风险评估和缓解计划方面被地方政府官员使用。 当地研究人员和学校学生参与野外工作也将为这些加勒比岛国家的科学教育和能力建设做出贡献。