| 13 May 2025
Numerical modelling framework for assessing dune effectiveness against coastal inundation
Abstract. Coastal inundation is one of the prominent natural hazards threatening both economic assets and human lives. Precise modeling of these events is vital for comprehensive risk assessment, yet there is a persistent gap in data availability and modelling accuracy for coastal flood mapping. In this study, we expanded the LISFLOOD-FP model's ability to simulate coastal floods by incorporating wave setup and swash, as well as the interaction with protective infrastructures like temporary dunes. This improved approach was applied to the coastline of Cesenatico, Italy, where dunes are built each winter as seasonal coastal defenses. We analyzed two storm events for which observational flood maps are available for validation: the 2015 Saint Agatha Storm, which saw intense waves breaching the dunes and causing extensive inland flooding, and the 2022 Denise Storm, when the dunes withstood the storm and successfully shielded the coast. Our results demonstrate that dunes are highly effective in mitigating inundation, particularly during the 2022 event. However, they also reveal that the failure of even a small portion of the dunes can lead to widespread inundation, emphasizing the need for optimized dune design. These findings represent a significant advancement toward developing a digital twin of coastal regions, providing valuable support for a range of coastal management activities.
Competing interests: Co-author Michalis Vousdoukas is employed by the company MV Coastal and Climate Research Ltd. Co-author Maurilio Milella is employed by the company Environmental Surveys S.r.l. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
Publisher's note: Copernicus Publications remains neutral with regard to jurisdictional claims made in the text, published maps, institutional affiliations, or any other geographical representation in this preprint. The responsibility to include appropriate place names lies with the authors.
