Author(s): Mohamed Oraby; Md Salauddin
Linked Author(s): Md Salauddin
Keywords: No Keywords
Abstract: Sea level rise and more frequent/intense storms are increasing coastal flooding and erosion by elevating water levels and amplifying wave action. Engineers increasingly adopt low-carbon soft solutions like sand nourishment, complemented by a rising trend in Nature Based Solutions (NBS) such as oyster reefs. NBS offer an alternative to traditional defenses because they can attenuate waves, adapt morphodynamically and enhance biodiversity. Yet, the design of NBS under varying metocean forcing remains poorly constrained. This work, undertaken within the BRICONS project for Kilkieran and Bertraghboy Bays, develops a long-term offshore wave characterization to link changing offshore conditions to the required vertical growth of future oyster reef installations. Hourly wave reanalysis data from 1950 to 2025 were validated with multiple nearshore wave buoys at different locations and periods. Annual and monthly statistics for average and maximum values are analyzed, and linear trends are normalized to express changes per year. Results show increasing trends in wave heights with a stronger signal (4 times) in extremes than in means. The analysis demonstrates how such trends can be translated into target NBS vertical growth rates so that their wave-dissipating function is not lost over time, which is governed by relative crest submergence and incident wave heights. The study also highlights the need for long-term nearshore data to complement offshore characterization in addition to site-specific larval transport modelling to identify reef locations with sufficient larval supply so that biological accretion can meet the target vertical growth rates over time.
Year: 2026