Explaining Rogue Waves in the Ocean Through Observations and Modelling

通过观测和建模解释海洋中的异常波浪

• 批准号: 2595418
• 金额: --
• 依托单位: University of Manchester
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2021
• 资助国家: 英国
• 起止时间: 2021 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2595418
• 关键词: Explaining; Rogue; Waves; Ocean; Through

Rogue waves are large, unexpected surface waves on the ocean that can cause catastrophic damage to offshore structures and vessels. These 'freak' or 'monster' waves are suspected to have capsized hundreds of ocean-going vessels and resulted in an unfortunate loss of life. A range of proposed explanations exist for the formation of rogue wave events including the effect of localised currents, abrupt depth transitions, modulation instability, dispersive (and directional) focusing enhanced by second-order bound nonlinearity, and Greenspan resonance through interaction with atmospheric convective storms. All are able to create rogue waves given the right set of theoretical conditions. However, debate is ongoing as to the dominant mechanism(s) for rogue wave formation in real seas.This project aims to make significant progress in our understanding for real ocean settings, primarily through the generation and analysis of numerical models created to assess regions (and time scales), where rogue wave observations have been made. This will be supported by a novel analysis of unexploited ocean datasets that contain rogue wave measurements (or indirectly hint at their occurrence).A suggested route to achieving the project aims is to develop spectral wave models to hindcast the wave conditions in the region of observed rogue wave events. The spectral conditions can then be used, in combination with local bathymetry, to drive a phase-resolved model (e.g. nonlinear potential flow) over a localised region. The statistical and spectral analysis of the resulting conditions can be used to identify a) did the model capture an enhanced likelihood of rogue wave events? and b) if so, what is the dominant cause?If the approach is successful in identifying the dominant cause(s) of rogue waves in oceans, then this will make significant advances in our understanding of rogue wave formation in real seas in addition to validating the methodology developed throughout the project for their assessment. The implications of these findings have the potential to be fundamentally significant with wide-ranging practical implications. With improved understanding, appropriate extreme 'design' conditions can be defined for the de-risking of offshore vessels and structures, and if locations and/or time scales can be identified which have an increased risk potential, these can potentially be avoided. Consequently, the results have the potential to reduce capital loss as well as loss of life.In addition, the work underpinning this project has the potential to answer a range of further unanswered additional research questions surrounding rogue waves. Key future research questions may include:1. Could these rogue waves (or the increased likelihood of) have been predicted?2. How spatially localised is the increased likelihood of rogue wave events?3. Using the developed framework, is it possible to identify 'ideal' (worst-case) input conditions for creating rogue wave events?4. Will rogue waves will become more common in the future climate? To address this question, we could produce a dataset of extreme waves from an ensemble of wave models forced by winds from climate projections.

流氓波是海洋上的大而意外的表面波，可能会对近海结构和容器造成灾难性损害。这些“怪胎”或“怪物”波被怀疑倾斜了数百艘海洋船只，并导致了不幸的生命损失。存在一系列提出的解释，用于形成流氓波事件，包括局部电流的影响，突然的深度转变，调节不稳定性，分散性（和定向）的焦点通过二阶结合非线性增强，以及通过与大气对流风暴的相互作用来增强的。考虑到正确的理论条件，所有这些都能够创建流氓波。然而，关于实际海洋中流氓波的主要机制的辩论正在进行中。该项目旨在在我们对真实海洋环境的理解中取得重大进展，主要是通过对评估区域（和时间尺度）创建的数值模型的生成和分析，在该地区进行了流氓波观测。这将通过对包含流氓波测量值的未开发的海洋数据集进行新的分析（或间接暗示其发生的情况）来支持。然后，可以将光谱条件与局部测深量法结合使用，以驱动局部区域上的相分辨模型（例如非线性电势流）。所得条件的统计和频谱分析可用于识别a）模型是否捕获了生动波动事件的可能性增强？ b）如果是这样，主要原因是什么？如果该方法成功地确定了海洋中流氓波的主要原因，那么除了验证整个项目中开发的方法以进行评估之外，这将在我们对实际海洋中流氓浪潮形成的理解中取得重大进步。这些发现的含义具有从根本上具有重要意义的实践意义。有了改善的理解，可以定义适当的极端“设计”条件，以降低海上容器和结构的风险，如果可以识别出具有增加风险潜力的位置和时间尺度，则可以避免这些风险。因此，结果有可能减少资本损失和丧生。此外，该项目的基础基础的工作有可能回答一系列围绕Rogue Wave的进一步未回答的其他研究问题。未来的关键研究问题可能包括：1。可以预测这些流氓波（或增加的可能性）吗？2。流氓波事件的可能性增加在空间上是如何定位的？3。使用开发的框架，是否可以识别创建Rogue Wave事件的“理想”（最坏的）输入条件？4。在未来的气候下，流氓波会变得越来越普遍？为了解决这个问题，我们可以从气候预测强迫的波浪模型中产生一个极端波的数据集。