Abstract Coastal risk assessments rely on proper quantification of storm-induced erosion and flooding, and often involve calculations via numerical models. When the real time-series data of a storm are not available as forcing conditions and only bulk information is accessible, synthetic simplified time-evolutions are assumed. The most common approach in coastal studies uses a symmetric triangular storm shape, characterised by the assumptions that the peak of the waves occurs in the middle of the storm, and that the forcing varies linearly. This study aims to investigate this additional source of uncertainty in hazard estimation, using the XBeach-1D model, to assess the differences in simulated erosion and flooding associated with real and synthetic storm definitions. Analysis is performed for real conditions ranging from moderate to extreme at the Northern Adriatic and North-Western Mediterranean coasts, using beach profiles ranging from dissipative to reflective. The storm definitions generate considerable differences in terms of wave power and timing at the peak of the storm. When synthetic storms were applied, coastal hazards were not adequately reproduced in most of the simulated cases. The energy of the storms, profile characteristics, local storm climates, and water levels did not consistently influence the differences between the synthetic- and reality-based outputs.

中文翻译：

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对称三角形合成风暴在海岸灾害建模中代表真实事件的效果如何

摘要 沿海风险评估依赖于对风暴引起的侵蚀和洪水的适当量化，并且通常涉及通过数值模型进行计算。当风暴的实时时间序列数据不可用作强迫条件并且只能获得大量信息时，假设合成的简化时间演变。沿海研究中最常见的方法是使用对称的三角形风暴形状，其特点是假设波浪的峰值出现在风暴的中间，并且强迫线性变化。本研究旨在使用 XBeach-1D 模型调查灾害估计中的这一额外不确定性来源，以评估与真实和合成风暴定义相关的模拟侵蚀和洪水的差异。分析是针对亚得里亚海北部和地中海西北部海岸从中等到极端的真实条件进行的，使用范围从耗散到反射的海滩剖面。风暴定义在风暴高峰时的波浪功率和时间方面产生了相当大的差异。当应用合成风暴时，在大多数模拟案例中没有充分再现沿海灾害。风暴的能量、剖面特征、当地风暴气候和水位并没有持续影响基于合成和现实的输出之间的差异。当应用合成风暴时，在大多数模拟案例中没有充分再现沿海灾害。风暴的能量、剖面特征、当地风暴气候和水位并没有持续影响基于合成和现实的输出之间的差异。当应用合成风暴时，在大多数模拟案例中没有充分再现沿海灾害。风暴的能量、剖面特征、当地风暴气候和水位并没有持续影响基于合成和现实的输出之间的差异。