Numerical Modelling of Wave Height using Wind-Tide Interactions in Coastal Flooding
Pantai Punggur, Batu Pahat is a bustling town located on the Southwest Coast of Peninsular Malaysia, situated along the west coast of Malaysia. Despite its bustling nature, the area is prone to coastal flooding. In response, coastal defence structures have been constructed to protect the coastline. However, the issue lies that this structure cannot fully prevent coastline exposure to wave overtopping caused by strong waves or coastal inundation from high tidal fluctuations that exceed normal sea levels. Pantai Punggur has undergone the concerning issue, and it is worsening. Therefore, this study uses numerical modelling (MIKE21 Software) to investigate the wave scenario from the historical data of wind and tide in Pantai Punggur, Batu Pahat. The study location was digitised, and a new model MESH was developed in the MIKE21 Zero MESH Generator. The historical data from the ERA5-Reanalysis Dataset covering all 12 months (2022) at one-hour intervals was collected. To validate the new model MESH, the RMSE method was employed, which required achieving a result below the 10% threshold. Correlation analysis was conducted monthly throughout the year and revealed distinct relationships between significant wave height (SWH) and wind speed (indicating wave overtopping) and tidal levels (indicating coastal inundation). The correlation between tidal levels and SWH showed a stronger correlation than with wind speed, with the highest R-value reaching 0.5886 (34.64%). Hence, it can be seen that the stronger correlation between tidal level and SWH compared to wind speed and SWH, suggests that tidal fluctuations have a more substantial impact on wave heights and the potential fall on coastal inundation rather than wave overtopping resulting in coastal flooding. The current studies provide essential information relevant to conservation practices and future planning.
Authors
Abstract
Pantai Punggur, Batu Pahat is a bustling town located on the Southwest Coast of Peninsular Malaysia, situated along the west coast of Malaysia. Despite its bustling nature, the area is prone to coastal flooding. In response, coastal defence structures have been constructed to protect the coastline. However, the issue lies that this structure cannot fully prevent coastline exposure to wave overtopping caused by strong waves or coastal inundation from high tidal fluctuations that exceed normal sea levels. Pantai Punggur has undergone the concerning issue, and it is worsening. Therefore, this study uses numerical modelling (MIKE21 Software) to investigate the wave scenario from the historical data of wind and tide in Pantai Punggur, Batu Pahat. The study location was digitised, and a new model MESH was developed in the MIKE21 Zero MESH Generator. The historical data from the ERA5-Reanalysis Dataset covering all 12 months (2022) at one-hour intervals was collected. To validate the new model MESH, the RMSE method was employed, which required achieving a result below the 10% threshold. Correlation analysis was conducted monthly throughout the year and revealed distinct relationships between significant wave height (SWH) and wind speed (indicating wave overtopping) and tidal levels (indicating coastal inundation). The correlation between tidal levels and SWH showed a stronger correlation than with wind speed, with the highest R-value reaching 0.5886 (34.64%). Hence, it can be seen that the stronger correlation between tidal level and SWH compared to wind speed and SWH, suggests that tidal fluctuations have a more substantial impact on wave heights and the potential fall on coastal inundation rather than wave overtopping resulting in coastal flooding. The current studies provide essential information relevant to conservation practices and future planning.
Citation
IR. TS. MUHAMMAD RIZAL RAZALI. 2025. Numerical Modelling of Wave Height using Wind-Tide Interactions in Coastal Flooding. Digital NAHRIM Publication Repository.