Collaborative Research: Holocene Tropical Cyclone Variability in the Western North Atlantic

飓风造成的破坏在上个世纪显著增加，这主要是沿海人口增加、城市化和财富增加的结果。最近飓风卡特里娜、艾琳和桑迪的影响突显了美国对热带气旋的脆弱性。不幸的是，北大西洋西部飓风发生的短暂工具记录(约160年)大大阻碍了理解调节飓风活动的驱动机制的努力。此外，飓风在任何特定地区登陆的相对罕见，进一步限制了从本已有限的数据集中提取有意义的模式。这一合作项目由伍兹霍尔海洋研究所和加尔维斯顿的德克萨斯农工大学的研究人员共同开展，旨在通过保存在沿海沉没坑和蓝洞中的飓风经过的沉积证据，将飓风活动的记录追溯到数千年前。在强烈的飓风袭击期间，风暴潮和海浪会调动和输送沙子和砾石等粗泥沙。其中一些粗大的沉积物被保存为细粒沉积物中的一层，这些沉积物通常沉积在沉降孔和蓝洞中。这些粗粒层可以用来重建数千年来的史前风暴事件，在这段时间里，沉坑和蓝洞一直在收集沉积物。目前的工作重点是开发巴哈马和牙买加过去热带气旋活动的长期记录。这些记录将补充佛罗里达和美国东北部狭长地带现有的记录，有助于阐明热带气旋活动的时空模式，并允许检查这种变化的气候驱动因素。这项工作的广泛影响包括更全面地了解过去数千年影响飓风活动的一系列气候因素。这种对自然变异性的更好的洞察对于为建模工作提供信息并评估这些风暴的未来风险至关重要。该项目还将提供一个平台，通过在本科生和研究生一级实践的跨学科研究经验，培训下一代地球科学家。

Damage from hurricanes has increased markedly over the last century, largely the result of increased coastal population, urbanization and wealth. The recent impacts of hurricanes Katrina, Irene, and Sandy highlight the vulnerability of the United States to tropical cyclones. Unfortunately, the short instrumental record of hurricane occurrence (~160 years) in the western North Atlantic significantly hampers efforts to understand the driving mechanisms responsible for modulating hurricane activity. Additionally, the relative rarity of hurricane landfalls at any particular region further limits the extraction of meaningful patterns from an already limited data set. This collaborative project, conducted by researchers at the Woods Hole Oceanographic Institution and Texas A&M University at Galveston, is aimed at extending the record of hurricane activity back thousands of years with sedimentary evidence of hurricane passage preserved in coastal sink holes and blue holes. During an intense hurricane strike, storm surge and waves mobilize and transport coarse sediment such as sand and gravel. Some of this coarse sediment is preserved as a layer in the finer grained sediments normally deposited in sink holes and blue holes. These coarse grained layers can be used to reconstruct prehistoric storm events over the thousands of years, throughout the time sink holes and blue holes have been collecting sediments. This current work is focused on developing these long-term records of past tropical cyclone activity from sites in the Bahamas and Jamaica. These records will complement existing records from the panhandle of Florida and the Northeastern US and will help elucidate spatial and temporal patterns in tropical cyclone activity and allow for the examination of the climatic drivers of this variability.Broader impacts of the work include a more comprehensive understanding of the array of climate factors that influence hurricane activity over the past several millennia. This improved insight into natural variability is essential to inform modeling efforts and assess future risks from these storms. The project will also provide a platform for training the next generation of geoscientists through practical, hands-on interdisciplinary research experiences at the undergraduate and graduate level.