Runups of Unusual Size: Predicting Unexpectedly Large Swash Events

这个项目的目标是提高我们对海洋海滩上异常大的海浪抬高事件的理解。这样的冲刺事件只出现在一小部分海浪中，但它们对于预报沙丘侵蚀、洪水泛滥和风暴期间的海岸洪水非常重要。第二种不寻常的上升事件也是不同的，因为它是突然和意外的，即使上升的陆地范围不是统计上的极端。这些大型和不同寻常的冲刺事件是美国太平洋西北部溺水死亡的主要原因。为了了解意外大型上升事件的原因，并开始预测其潜在发生，该项目将使用现有数据、新的多年数据集和数值模式模拟的层次，并将这些事件与各种发生机制联系起来。最后，将开发和测试一个模型来预测此类事件的风险。该小组将与国家气象局办公室合作，并探索其他渠道向公众传达严重事件预报。除了加强公共安全外，该项目还将有助于沿海管理工作。这些努力依靠预测来勾勒出洪水危险区和适合开发的区域。此外，研究的数值模拟部分的研究结果将记录并有可能提高近岸水动力模型的准确性/能力，这将有利于其他地理环境中的沿海地区管理。最后，该项目将通过直接让研究生和本科生参与研究来促进教育工作，特别关注来自代表性不足群体的个人的夹带。过去十年来，对漩涡带水动力学的研究取得了持续的进展，主要集中在总体和极端增长统计数据的特征上。然而，大型事件的物理原因，特别是意外事件的物理原因，受到的关注要少得多。该项目将进行数据收集和分析以及数值模型研究，旨在区分与叠加有关的线性生成机制和与井筒捕获有关的非线性生成机制、入射波-亚重力波相互作用以及大型和意外抬升事件的上冲反冲事件。两个截然不同的海滩，玛瑙海滩和北卡罗来纳州的Duck之间的地貌动力学差异，将有助于揭示海滩类型在大型和不寻常的助跑事件的产生中所起的作用。这些观测将使团队能够在风暴期间测试和改进简单的极端助跑参数模型的技能。

The goal of this project is to improve our understanding of unusually large wave runup events on ocean beaches. Such runup events are seen with only a small fraction of the waves, yet they are important for the prediction of dune erosion, inundation and coastal flooding during storms. A second type of unusual runup event is also distinguished in that it is sudden and unexpected even if the landward reach of the runup is not a statistical extreme. These large and unusual runup events are the leading cause of death by drowning along the U.S. Pacific Northwest. In order to understand the causes of unexpectedly large runup events, and to begin to forecast their potential occurrence, this project will use existing data, a new multi-year data set and a hierarchy of numerical model simulations and link the events to various generation mechanisms. Finally a model will be developed and tested for forecasting the risk of such events. The team will work with the National Weather Service offices as well as exploring other outlets to communicate severe event forecasts to the public. In addition to increased public safety, this project will also help coastal management efforts. These efforts rely on predictions to outline flood hazard zones and regions appropriate for development. Additionally, findings from the numerical modeling portion of the study will document and potentially advance the accuracy/capabilities of nearshore hydrodynamic models, which will benefit coastal zone management in other geographic settings. Finally the project will contribute to education efforts by directly involving graduate and undergraduate students in the research, paying specific attention to the entrainment of individuals from under-represented groups.The study of swash zone hydrodynamics has seen sustained progress over the last decade, with much of the focus on the characterization of bulk and extreme runup statistics. However, the physical causes of large, and especially of unexpected, events have received considerably less attention. This project will conduct data collection and analysis and numerical model studies designed to distinguish between linear generation mechanisms related to super-position and nonlinear generation mechanisms related to bore-bore capture, incident wave-infragravity wave interactions and uprush-backwash events for large as well as unexpected runup events. Morphodynamic differences between two drastically different beaches, Agate Beach, OR and Duck, NC, will help reveal the role of beach type on the generation of both large and unusual runup events. The observations will allow the team to test and improve the skill of simple extreme runup parametric models during storms.