Tree-Ring Reconstruction of Flood Dynamics on the Mississippi River and Its Principal Tributaries

密西西比河及其主要支流洪水动力学树轮重建

• 批准号: 1359801
• 负责人: Matthew Therrell
• 金额: $ 29.69万
• 依托单位: University of Alabama Tuscaloosa
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-07-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1359801&HistoricalAwards=false
• 关键词: Tree; Ring; Reconstruction; Flood; Dynamics

This research project will develop high-resolution, multi-century reconstructions of major flooding in the Mississippi River Basin based on analyses of tree rings and to use these reconstructions to help determine the true natural variability of large magnitude flooding prior to the modern period of direct flood measurements. These reconstructions will provide a long-term context for analyses of extreme flood events that have occurred in the modern period and allow the examination of the role played in destructive flooding by regional and large-scale climate variability and other natural and human-related factors. Results of the research project will greatly increase basic understanding of long-term flood variability in the region and help develop and refine techniques useful for the study of flood history in large-river systems in North America and elsewhere. Beyond meeting specific research objectives, the project will provide education and training opportunities for undergraduate and graduate students and will provide for improved teaching of undergraduate students and others based on project findings that demonstrate the relevance of atmospheric science as well as the importance of societal resilience to natural hazards.Destructive flooding long has long plagued many communities along major rivers, including the Mississippi River and its principal tributaries. For more than a century, scientists and engineers have attempted to determine the frequency and magnitude of flooding in this river system. Scientists also have sought to understand not only the links between flooding and natural climate variability but also how potential climate change and direct human modification of the hydrology of the river may affect future flood patterns. This project will address several methodological and theoretical issues. The principal methodological questions concern whether it is possible to quantitatively reconstruct and model extreme flooding prior to the instrumental period and to determine how well the observational record represents the envelope of natural variability. Answers to both of these questions are necessary to determine broader questions concerning the link between extreme flooding and climate variability, including the questions of whether and how changes in climate and other natural and human systems may affect flood behavior and the risk to those who reside in river basin. This project will answer these questions using both tree-ring records of flooding and hydrological models to estimate the occurrence, magnitude, and discharge of major pre-instrumental floods. This approach has rarely been used in the past, and it should provide the necessary long-term context for extreme events observed in the modern period and reveal relevant links to climate forcing that will help answer questions regarding the potential impact of climate and other changes on this river system. This approach holds great promise for being applied in other river basins and for use to address other natural-hazard questions.

该研究项目将根据对树环的分析进行高分辨率，多世纪的重建，重建密西西比河盆地的主要洪水，并使用这些重建来帮助确定现代直接洪水测量现代之前的大量洪水的真正自然变异性。 这些重建将为现代发生的极端洪水事件的分析提供长期背景，并允许检查区域和大规模气候变异性以及其他自然和人类相关因素在破坏性洪水中所起的作用。研究项目的结果将大大提高对该地区长期洪水变异性的基本了解，并有助于开发和完善技术，可用于研究北美和其他地方大型河流系统中的洪水历史。除了达到特定的研究目标外，该项目还将为本科和研究生提供教育和培训机会，并根据项目的发现，改善了本科生和其他人的教学，这些发现证明了大气科学的相关性以及社会抵抗力的重要性以及自然危害对自然危害的重要性。毁灭性的洪水长期漫长的许多社区在包括Mississipsippi river的主要社区中长期欺骗了许多社区。 一个多世纪以来，科学家和工程师试图确定该河流系统中洪水的频率和幅度。 科学家还试图不仅了解洪水与自然气候变化之间的联系，而且还试图了解潜在的气候变化和对河流水文学的直接修改可能影响未来的洪水模式。 该项目将解决一些方法论和理论问题。主要的方法论问题涉及是否可以在仪器期之前定量重建和建模极端洪水，并确定观察性记录代表自然变异性的信封的程度。 这两个问题的答案对于确定有关极端洪水和气候变异性之间联系的更广泛的问题是必要的，包括有关气候和其他自然和人类系统的变化是否以及如何影响洪水行为的问题以及居住在河流流域的人们的风险。 该项目将使用洪水和水文模型的树环记录来回答这些问题，以估算主要前洪水的发生，大小和排放。 过去很少使用这种方法，它应该为现代观察到的极端事件提供必要的长期背景，并揭示与气候强迫的相关联系，这将有助于回答有关气候和其他变化对该河流系统的潜在影响的问题。 这种方法对在其他河流盆地中应用并用于解决其他自然危害问题有很大的希望。