Collaborative Research: Coastal Geomorphic Consequences of Wave Climate Change

合作研究：海浪气候变化的沿海地貌后果亚当斯、麦克纳马拉、摩尔、默里海平面上升与全球气候变化相关的潜在影响已被广泛宣传。然而，海岸线的变化也受到海洋风暴性变化和由此产生的深水波浪场的影响。风暴波的高度、周期和方向的统计分布的变化将影响波浪驱动的沿岸泥沙输移，通过一些地方的岸线后退(侵蚀)和另一些地方的岸线推进(淤积)来推动岸线形状的快速调整。该项目的目标是提高我们对各种陆架形态的沙质海岸对一系列风暴-气候变化情景的响应的理解。该项目的范围可以概括为一系列具体问题：暴风雨的变化如何与大陆架水深测量相互作用，以重新配置沿海平面？从近几十年来已经发生的波浪气候变化中可以预料到海岸地貌响应的大小和模式是什么？我们能察觉到这样的反应吗？未来哪些大型岸线配置最容易受到侵蚀加剧的影响？该项目将采用波浪变换(浅化和折射)和沿岸沉积物输送的数值模拟，以探索一系列波浪气候和大陆架情景。以前的数值模拟工作帮助我们理解了大规模的海岸演变，但依赖于关于波浪变换的简单假设。这些简单的假设可能会让人质疑以前的模型结果与实际海岸线的关联程度。通过采用更复杂的波浪/陆架相互作用的数值处理方法，该项目应能提高海岸侵蚀和淤积的位置和程度的预测精度。对历史海岸线变化模式的分析将评估选定的海岸线可能已经对风暴行为的变化做出了反应，并将测试哪些模型组件的组合最能再现观测结果。结果将有助于评估敏感海岸线类型对未来风暴和波浪气候变化情景的反应。全球气候变化可能会改变海浪条件，从而导致海岸线形状的变化。这项研究将探讨海浪气候变化对大范围大陆架海岸侵蚀模式的影响。通过将最先进的波浪模型(计算波浪在接近海岸时如何重新分配其能量)与现有的海岸线变化计算机模型相结合，我们将确定在一系列可能的气候情景下最有可能发生严重变化的海岸类型。历史海岸线变化信息将被用来记录已经在进行的海岸重新配置，并评估计算机模型的性能。该项目的成果将有助于向居民、开发商、政策制定者、科学家、工程师和其他利益相关者提供关于沿海地区管理的决策。

Collaborative Research: Coastal Geomorphic Consequences Of Wave Climate Change Adams, McNamara, Moore, MurrayThe potential effects of sea-level rise, associated with global climate change, have been widely publicized. However, shoreline change is also influenced by changes in ocean storminess and the resulting deep-water wave field. Changes in the statistical distribution of heights, periods, and directions of storm-generated waves will affect wave-driven longshore sediment transport, driving rapid adjustment of coastline shape through shoreline retreat (erosion) in some places and shoreline advance (accretion) in others. The goal of this project is to improve our understanding of sandy coast shoreline response to a series of storm-climate-change scenarios over a range of shelf morphologies. The scope of this project can be summarized as a series of specific questions: How do variations in storminess interact with continental shelf bathymetry to reconfigure coastal planforms? What are the magnitudes and patterns of coastal morphologic responses that can be expected from the shifts in wave climate that have already occurred in recent decades? Can we already detect such responses? What large-scale shoreline configurations are most vulnerable to increased erosion in the future? This project will employ numerical modeling of wave transformation (shoaling and refraction) and longshore sediment transport to explore a range of wave climate and continental shelf scenarios. Previous numerical modeling efforts have aided our understanding of large-scale coastal evolution, but relied on simple assumptions regarding wave transformation. These simple assumptions may bring into question the degree to which previous model results can be related to actual coastlines. By incorporating more sophisticated numerical treatments of wave/shelf interactions, this project should provide improved accuracy in projections of locations and magnitudes of coastal erosion and accretion. Analysis of historical shoreline-change patterns will both evaluate how select coastlines might already be responding to changes in storm behaviors, and will test which combinations of model components best reproduce observations. Results will help evaluate the response of sensitive coastline types to scenarios of future storm and wave-climate changes.Global climate change may alter ocean wave conditions thereby leading to changes in coastline shapes. This research will address the impacts of wave climate change on patterns of coastal erosion for a wide range of continental shelves. By incorporating state-of-the-art wave models, which calculate how waves redistribute their energy as they approach shore, into a pre-existing computer model of shoreline-change, we will determine the types of coasts that are most likely to change severely for a range of possible climate scenarios. Historical shoreline-change information will be used to document coastal reconfiguration already in progress, and to evaluate computer model performance. Results of this project will help to inform residents, developers, policy makers, scientists, engineers, and other stakeholders as they make decisions about the management of coastal regions.