Beach Morphodynamics and Evolution of Monsoon Dominated Coast in Selangor, Malaysia

Abstract

Human-induced climate change has intensified coastal hazards globally, with shoreline erosion emerging as a critical challenge for monsoon-dominated coasts. Along the Selangor coast of Peninsular Malaysia, erosion processes are strongly influenced by Northeast Monsoon (NEM) wind and wave regimes, which govern sediment transport and shoreline stability. This study examines the geomorphological and morphodynamic characteristics of NEM-dominated beaches and their relationship with erosion and accretion dynamics along the Selangor coast. Five representative coastal sectors - Bagan Pasir, Pantai Jeram, Bagan Sungai Janggut, Pantai Kelanang, and Kg Batu Laut -were analysed using multi-temporal datasets for 2014, 2020, and 2023. Shoreline change and beach morphology were quantified through the integration of Land Satellites Program (LANDSAT) - derived shoreline extraction and conventional beach profiling to assess spatial and temporal variability and to validate remotely sensed observations. This approach enables the identification of short-term erosional and accretionary responses to seasonal monsoonal forcing. Results reveal marked spatial heterogeneity in erosion intensity, reflecting differences in coastal geomorphology, sediment availability, and exposure to monsoonal wave energy. The findings underscore the continued relevance of geomorphological controls in shaping erosion risk and associated socio-economic impacts. By updating earlier national assessments, this study provides an empirical basis for zone-specific coastal management and climate adaptation strategies along the Selangor coast.