Storm sequence chronology and initial profile morphology controls on beach erosion. (January 2023)

• Record Type: Journal Article
• Authors: Oo, Ye Htet; Vieira da Silva, Guilherme; Zhang, Hong
• Is Part Of: Applied ocean research. Volume 130(2023)
• Publication Date: 2023-01
• Subjects: Total water level -- Storm group -- XBeach -- Wave power -- Beach profile; Ocean engineering -- Periodicals; 620.416205
• DOI: 10.1016/j.apor.2022.103431
• Languages: English
• ISSNs: 0141-1187

Abstract

Highlights: Beaches erosion induced by a storm group and its sequences were analyzed at a wave-dominated zeta coastline. A 7% higher wave height exposure can potentially double the cumulative erosion. Relationship between beach erosion and water level varied when the beach eroded about 20% of its pre-storm volume. Erosion continues unless the current storm wave power is 76% lower than previous storm. Abstract: Projected changes in frequency and intensity of extreme storms have been widely reported in the literature. While individual storms can transport large amounts of sand creating significant beach erosion, affecting communities, and damaging infrastructure, storm groups that happen close together without time for the beach to recover can further intensify these impacts. The aim of this study is to quantify the total beach erosion induced by a storm group and the importance of the storm sequence chronology (SC) on the total eroded volume. To achieve this, a morphological numerical model was applied to analyze the response of three different initial beach profiles. A measured storm group of four storms was simulated and the storm order were rearranged to assess its importance to total beach erosion. The results showed that the beach continued to erode unless the wave power of current storm was at least 76% (on average) lower than the previous storm, and that the relationship between total water level and erosion rate were inversely proportional while the beach volume was over 80% of its pre-storm volume. This relationship became directly proportional when the volume was below 80% of its pre-storm volume. This study assesses the beach erosion depending on combination of different storm order and pre-storm beach volume at beaches with varying wave attenuation.