Collaborative Research: Modeling wave breaking onset and dissipation in energy-conserving models for surface waves

波浪破碎是影响近海和近岸各种具有重大社会意义的海洋和沿海科学和工程问题的关键过程。这项研究将开发用于检测波浪破碎的起始、破碎条件和由波浪破碎引起的能量耗散的算法，用于相分辨海浪传播模型。将根据最近的高保真数值模拟以及实验室和现场数据进行广泛的验证和敏感性分析。开发的公式的稳健性也将与现有的破裂模型进行比较。除了开发参数化之外，这项研究还将量化与业务相分辨波浪模型中的波浪破碎的各种参数化相关的不确定性。通过更好地识别风暴和极端事件期间的模型技能和不确定性，风暴条件下的模型-现场数据比较将使沿海工程界受益。这项工作将改进对相分辨波浪模型中破碎波的发生和严重程度的预测，从而导致：(I)更准确地表示波浪强迫(对水流、沉积物过程、海气相互作用等)。包括内陆架、冲浪区和河口在内的各种水深；(Ii)改进了沿海和海洋结构物以及船舶设计的设计分析和安全性。通过改进沿海复原力战略，更好地预测高能量/风暴事件期间的破坏过程和影响，也将使公众受益。华盛顿大学(UW)的一名初级科学家是首席PI，他将得到更资深的联合PI的指导，这将帮助他过渡到永久任命。该项目将支持特拉华大学的一名女研究生，她将由私人投资机构共同提供建议。在华盛顿大学一年一度的“发现日”活动上，将进行推广。提出了一种新的、统一的、稳健的闭合模式，用于在相分辨、节能的面波模式中对波浪破裂的开始和发展进行参数化，适用于Boussinesq(通常用于浅水)和高阶谱(HOS，通常用于深水)模式。这项拟议的工作是基于高保真数值模拟的最新结果，这些结果表明，当波峰在任意深度接近破裂时，单个波峰的开始和破裂强度可以仅由其局部特性来确定。新的闭合模型将改进现有的方法，提供一种适合于单个波峰的公式，而不是根据波列的一般特征进行校准。将根据最近的高保真数值模拟、可用的实验室实验以及最近和正在进行的风暴条件下的现场观测，对建议的破裂关闭模型进行广泛的验证和敏感性分析。后一种数据及其在数值模拟中的使用都是非常新颖的，并将建立独特的模型场数据比较程序，因为它需要使用波场重建算法来初始化相分辨模型。建议的打破关闭模式的健壮性也将与现有的打破模式进行比较。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Wave breaking is a crucial process affecting a variety of ocean and coastal science and engineering problems both offshore and in the nearshore of great societal importance. This study will develop algorithms for the detection of wave breaking initiation, breaking conditions, and energy dissipation due to wave breaking, for use in phase-resolving ocean wave propagations models. Extensive validation and sensitivity analysis will be performed against recent high-fidelity numerical simulations and laboratory and field data. The robustness of the developed formulations will also be compared with existing breaking models. In addition to developing the parametrizations, this study will quantify uncertainties associated with various parametrizations of wave breaking in operational phase-resolving wave models. The model-field data comparison during storm conditions will benefit the coastal engineering community by better identifying model skill and uncertainty during storms and extreme events. The work will improve predictions of the occurrence and severity of breaking waves in phase-resolving wave models leading to: (i) a more accurate representation of wave-forcing (on currents, sediment processes, air-sea interactions, etc.) over a range of water depths, including the inner shelf, the surf zone, and river mouths; (ii) improved design analyses and safety for coastal and ocean structures and ship design. A better prediction of breaking processes and impacts during energetic/storm events will also benefit the public through improved strategies for coastal resilience. A junior scientist at the University of Washington (UW), the lead PI, will be mentored by the more senior co-PIs, which will help him transition to a permanent appointment. The project will support a female graduate student at the University of Delaware, who will be co-advised by the PIs. Outreach will be conducted at the annual "Discovery Days" event at the University of Washington.A new, unified, and robust closure model for parameterization of the onset and progression of wave breaking in phase-resolving, energy-conserving surface wave models is proposed, applicable to Boussinesq (commonly used in shallow water) and High-Order Spectral (HOS, commonly used in deep water) models. The proposed work is motivated by and builds on recent results obtained using high-fidelity numerical simulations, which establish that the onset and strength of breaking of an individual wave crest can be determined solely from local properties of the evolving crest as it approaches breaking in arbitrary depth. The new closure model will improve on existing methods by providing a formulation that is adaptive to individual wave crests, as opposed to being calibrated based on the general features of the wave train. Extensive validation and sensitivity analysis of the proposed breaking closure model will be performed against recent high-fidelity numerical simulations, available laboratory experiments, and recent and ongoing field observations during storm conditions. Both the latter data and its use in numerical modeling are quite novel and will establish a unique model-field data comparison procedure as it requires initialization of the phase-resolving model using a wave field reconstruction algorithm. The robustness of the proposed breaking closure model will also be compared with existing breaking models.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.