Impacts of sea level rise on wave overtopping rates around the coast of England

Hames, Dominic; Vidal, Isabel; Ben, Gouldby

Abstract

There is unequivocal evidence that global sea levels are rising. It is therefore inevitable there will be socioeconomic impacts as a result of this. To aid mitigation, and the implementation of adaptation measures, it is vital the magnitude of the potential impact is quantified. Current approaches in the UK make simplifying assumptions regarding the relationship between present-day and future economic damage relating to coastal flood risk. The analysis undertaken here supports studies of an improved impact of sea level rise by providing national-scale estimates of changes in wave overtopping rates and flood defence overflow rates, as a result of different amounts of sea level rise. The analysis involves the application of components of an existing risk-based coastal flood risk analysis method. A subset of almost 600 flood defence assets around the country has been analysed for sea level rise rates up to 1 m. The resulting analysis shows that, on average, the wave overtopping rate increases by up to 150 times above present-day rates for lower return periods and by up to five times for higher return periods. This differential arises as a result of non-linearities in overtopping rates with increasing extreme sea levels.

• Journal Article Type: Article
• Acceptance Date: Jun 29, 2022
• Online Publication Date: Oct 14, 2022
• Publication Date: Jul 31, 2023
• Deposit Date: Jan 11, 2023
• Publicly Available Date: Oct 15, 2023
• Journal: Proceedings of the Institution of Civil Engineers: Maritime Engineering
• Print ISSN: 1741-7597
• Electronic ISSN: 1751-7737
• Publisher: Thomas Telford
• Peer Reviewed: Peer Reviewed
• Volume: 176
• Issue: 3
• Pages: 110-117
• DOI: https://doi.org/10.1680/jmaen.2021.020
• Keywords: Climate change; coastal engineering; embankments
• Public URL: https://uwe-repository.worktribe.com/output/10336840
• Publisher URL: https://www.icevirtuallibrary.com/doi/10.1680/jmaen.2021.020