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

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 年极具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当地、区域和全球气候状况可能发生的重大变化之间关系的争论。 基于仪器的气候记录仅存在于相对较近的时期，这一事实阻碍了研究历史趋势的尝试。 古风暴学可以利用代理记录来克服仪器记录的局限性，并有助于识别现代记录中不明显的飓风频率变化。 该博士论文研究项目将通过对沿海湖泊沉积岩芯的地层分析，定量评估和描述飓风唐娜对加勒比北部三个岛屿的地貌和沉积学影响，从而建立第一个广泛的古风暴学现代模拟研究。 1960 年，飓风唐娜直接袭击了加勒比海岛国巴布达、安圭拉和阿克林斯岛（巴哈马），为严重的 4 级飓风，随后在佛罗里达州南部登陆并肆虐美国大西洋海岸，沿途造成了巨大的破坏和人员伤亡。 这项研究将检验唐娜在三个加勒比岛屿上造成过度冲刷事件的假设，该事件会在沿海后障壁湖沉积物中以过度冲刷沙层的形式留下可检测到的记录。 唐娜的地层记录将与最近也影响岛屿的其他已知强度飓风的地层记录进行比较，以便可以建立飓风强度和代理信号强度（例如沙层厚度）之间的现代关系。 通过使用多个地质和生物代理以及放射性同位素测年（14C 和 137Cs），飓风唐娜的地层特征将被识别并用于校准史前飓风袭击的代理记录，以重建全新世晚期的历史。北加勒比地区的飓风活动。 重建北加勒比地区的长期飓风历史将与加勒比地区其他地区正在进行的古风暴学研究相结合，解释整个盆地范围内的飓风模式变化，从而解释飓风模式的变化。背后的强制机制。 该项目意义重大，因为它通过建立对代理记录的校准和解释至关重要的全面的现代模拟方法，为古风暴学的年轻科学做出了贡献。 该项目还将建立北加勒比地区史前飓风袭击的第一个代理记录，从而填补当前大西洋古飓风知识和数据网络的巨大空白。 这些来自加勒比海北部的新代理记录对于检验百慕大高假说至关重要，该假说是新兴的古风暴学领域的基石。 这项研究有许多实际应用，对加勒比地区的社会具有深远的意义。 迫切需要了解加勒比地区飓风活动的时空变化以及造成这种变化的气候机制。 这项研究将产生计算北加勒比地区飓风重现期和年度登陆概率所必需的长期代理记录。 这些数据具有巨大的社会价值，地方政府官员可以将其用于风险评估和缓解规划。 当地研究人员和学生参与实地考察也将有助于这些加勒比岛国的科学教育和能力建设。