Sensitivity of Storm-Induced Hazards in a Highly Curvilinear Coastline to Changing Storm Directions. The Tordera Delta Case (NW Mediterranean)
Sensitivity of Storm-Induced Hazards in a Highly Curvilinear Coastline to Changing Storm Directions. The Tordera Delta Case (NW Mediterranean)
复制标题
高曲线海岸线风暴引发的灾害对风暴方向变化的敏感性。
作者：
M. Sanuy;J. Jimenez
极端的沿海风暴，特别是发生在城市化海岸线密集的地区，是最具破坏性的自然灾害之一。沿海风暴造成的主要危害是淹没和侵蚀，需要准确评估其规模和范围，以便有效管理沿海风险。使用最先进的基于地貌动力学过程的模型正成为标准，大多数模型适用于坡度平缓的直线海岸线。在这项研究中，XBeach模型被用来评估海岸响应曲线敏感的三角洲海岸粗泥沙和陡坡（中间反射条件）。经过检验的假设是，波浪方向的变化可能会导致风暴引起的灾害的严重程度发生很大变化。该模型进行了测试，对现场数据的圣埃斯泰夫风暴（2008年12月），获得整体BSS（布瑞尔技能得分）得分出现的形态反应为0.68。随后，将2008年的地震作为基线情景，创建覆盖NE到S范围的合成地震。结果表明，风暴引起的灾害沿着一个高度弯曲的海岸是非常敏感的波方向的变化。因此，即使在风暴相对稳定的气候情景下，波浪方向的潜在变化也可能显著改变灾害状况，因此，需要在可靠的损害风险评估中加以考虑。
Extreme coastal storms, especially when incident in areas with densely urbanized coastlines, are one of the most damaging forms of natural disasters. The main hazards originating from coastal storms are inundation and erosion, and their magnitude and extent needs to be accurately assessed for effective management of coastal risk. The use of state-of-art morphodynamic process-based models is becoming standard, with most being applied to straight coastlines with gentle slopes. In this study, the XBeach model is used to assess the coastal response of a curvilinear sensitive deltaic coast with coarse sediment and steep slopes (intermediate-reflective conditions). The tested hypothesis is that changes in wave direction may cause large variations in the magnitude of storm-induced hazards. The model is tested against field data available for the Sant Esteve Storm (December 2008), obtaining an overall BSS (Brier Skill Score) score on the emerged morphological response of 0.68. Later, the 2008 event is used as baseline scenario to create synthetic events covering the range from NE to S. The obtained results show that storm-induced hazards along a highly curvilinear coast are very sensitive to changes in wave direction. Therefore, even under climate scenarios of relatively steady storminess, a potential shift in wave direction may significantly change hazard conditions and thus, need to be accounted for in robust damage risk assessments.