Impact of sea level rise on the extreme hydrodynamic effects on coastal cultural heritage

Sea level rise (SLR), driven by climate change, poses a significant threat to coastal cultural heritage (CH) sites by exacerbating the intensity and frequency of extreme hydrodynamic events such as storm surges and wave impacts. These intensified processes can lead to accelerated erosion, structural instability, and increased vulnerability of CH sites. Over time, the cumulative effects of rising seas and amplified hydrodynamic forces may result in irreversible damage to these invaluable assets, threatening their historical, cultural, and economic significance. Despite growing awareness of these risks, a comprehensive understanding of the specific hydrodynamic effects associated with SLR on CH sites remains limited, creating a critical gap in developing effective mitigation strategies tailored to their preservation.

As part of the Horizon Europe project TRIQUETRA, this study investigates the effects of SLR on extreme hydrodynamic impacts imposed on coastal CH through advanced computational fluid dynamics (CFD) simulations. The Volume of Fluid (VOF) method is employed to model air-water interactions and track the evolution of waves and surges under varying sea level scenarios. Key hydrodynamic parameters, such as wave height, pressure distribution, and force intensity, are analyzed across multiple sections representative of the CH site with diverse cliff morphologies. Sensitivity analyses are conducted to ensure the robustness of the numerical framework and to explore the influence of different SLR scenarios on wave dynamics and their subsequent effects on coastal structures.

The results reveal that even moderate increases in sea level significantly amplify wave forces and pressure distributions on coastal structures, particularly under extreme weather conditions. The findings also demonstrate that specific morphological features, such as steep slopes or structural irregularities, affect the impact of hydrodynamic forces. This intensification poses a severe threat to the stability of CH sites, emphasizing the urgency of integrating SLR projections into comprehensive risk assessments and conservation planning to mitigate long-term impacts effectively. By advancing the understanding of SLR-induced hydrodynamic effects, this research provides a critical framework for assessing vulnerabilities and developing site-specific mitigation measures. The insights gained are essential for protecting coastal CH sites from the compounded effects of climate change.

Acknowledgments: This work is based on procedures and tasks implemented within the project “Toolbox for assessing and mitigating Climate Change risks and natural hazards threatening cultural heritage—TRIQUETRA”, which is a Project funded by the EU HE research and innovation program under GA No. 101094818.