Coupled coastal monitoring framework for the analysis of beach stability and nearshore hydrodynamics of a structure influenced medium energy coast in India

• Published in: Ocean & coastal management 2023-05, Vol.239, p.106619, Article 106619
• Main Authors: Ramesh, M., Swathy Krishna, P.S., Amrutha Raj, V., Sheela Nair, L.
• Format: Article
• Language: English
• Subjects: Coastal morphology; Coastal structures; Coastal video monitoring; Nearshore hydrodynamics; Numerical modelling; Remote sensing
• ISSN: 0964-5691; 1873-524X
• DOI: 10.1016/j.ocecoaman.2023.106619

This study presents a Coupled Coastal Monitoring Framework (CCMF) that integrates remote sensing (CoastSat), video beach monitoring system (VBMS), and numerical modelling to analyse the morphology and hydrodynamics of a structure-influenced beach. A 10.2 km stretch of straight beach with an artificial breakwater along the Kozhikode coast of Kerala, India, is selected for the study. The shoreline change analysis revealed that 38% of the total coast is under erosion, with the northern sector of the breakwater being highly erosive and the southern sector being stable. Continuous monitoring from the VBMS confirmed the stability of the southern sector with varying erosion accretion trends during 2018–21. Coastal morphological features such as double bars, cusps, and rip-like formations were identified through the VBMS, validated and analysed in detail with distinct wave-current interactions and sediment transport through numerical modelling. The study concludes that the breakwater is effectively protecting the beach adjacent to the south but has disturbed longshore transport, potentially leading to increased erosion to the north. The proposed CCMF provides real-time and post-performance monitoring of structure-influenced beaches, enabling timely decision-making at critical locations and appropriate remedial measures for efficient coastal management. •Coupling of satellite remote sensing, coastal video monitoring and numerical model.•Hydrodynamics of breakwater influenced medium energy coast.•Analysis of coastal erosion trends and identification of erosion hotspots.•Extraction of morphological features viz. double bar, cusp and rip channels.•Identification of two less intensity rip hotspots at Kozhikode beach, India.