01-05 December 2025
INCOIS, Hyderabad, India.
| Abstract Submission No. | ABS-05-0131 |
| Title of Abstract | Monsoon High Wave-Induced Coastal Inundation Along the Kerala Coast: A Coupled Wave-Hydrodynamic Modelling Approach |
| Authors | V RAAM BALAJI*, K. G. Sandhya, R S Mahendra, Gaurav Khairnar, P A Francis |
| Organisation | Indian National Centre for Ocean Information Services (INCOIS) |
| Address | SVPG Boys Hostel, NRI Colony, Kakatiya Hills, Vasanth Nagar Colony, Pragathi Nagar Hyderabad, Telangana, India Pincode: 500090 E-mail: rb.veerasekaran-p@incois.gov.in |
| Country | India |
| Presentation | Oral |
| Abstract | The southwest coast of India, particularly Kerala, is highly vulnerable to coastal inundation during the southwest monsoon. Persistent high-energy wave conditions driven by strong monsoonal winds often coincide with elevated tidal phases, leading to flooding across low-lying coastal regions. Accurate prediction of such events requires a coupled wave-hydrodynamic modelling framework capable of resolving nonlinear wave-tide interactions and terrain-driven flood propagation. This study employs a fully coupled ADCIRC+SWAN (ADCSWAN) model to simulate monsoon wave-driven coastal flooding. Wave boundary conditions from WAVEWATCH III are provided to SWAN to incorporate remotely generated monsoonal high waves and swells into the coupled ADCSWAN model domain. ADCIRC simulates hydrodynamic processes, while SWAN resolves the nearshore wave dynamics. The model is configured on an unstructured inundation mesh developed from high-resolution (100 m) merged bathymetric and topographic datasets generated by INCOIS. High-resolution wind (0.1° spatial, 3-hourly temporal) and sea-level pressure data from ECMWF are used to force the coupled model. To further refine the flood extents, head-loss downscaling was applied using a 5 m resolution DEM based on Airborne Laser Terrain Mapping (ALTM) data. Hindcast simulations were performed for a recent monsoon high wave-induced inundation event along the Kerala coast. Model performance was evaluated using tide gauge observations, waverider buoy data, and field-surveyed inundation extents. The results demonstrate good agreement with observations and underscore the dominant influence of wave setup and wave-tide interactions in determining inundation characteristics. This coupled modelling framework offers a reliable tool for understanding and forecasting monsoon wave-induced coastal flooding. It supports the development of operational early warning systems and enhances risk management strategies for the climate-sensitive coastal regions. |
| Are you part of IIOE-2 endorsed project | no |
| Keywords | Southwest Monsoon, Monsoon High Waves, Coastal Inundation, SWAN+ADCIRC, WAVEWATCH III, Head-Loss Downscaling. |
| For Awards | yes |
| Date Of Birth | 20-12-1996 |
| ECSN Registration Number | IIOE2-ECSN-0117 |