Multi-platform shoreline change monitoring in Mid-Central Vietnam using satellite imagery, coastal video, and numerical modeling

Monitoring shoreline change on monsoon-dominated coasts requires observations that capture both long-term regional trends and short-term seasonal variability. This study presents an integrated shoreline-monitoring framework for the Mid-Central Vietnam coast by combining multi-decadal satellite observations (1990–2024; CoastSat), continuous coastal video monitoring at My Khe Beach (2023–2024), and process-based numerical modeling (Wave 2D-GenCade) across four representative beaches: Gio Hai, Lang Co, My Khe, and Tam Tien. Satellite analysis reveals site-dependent and spatially variable shoreline change, with different long-term tendencies among the four beaches rather than a uniform regional erosional pattern. At My Khe Beach, video observations captured monsoon-driven shoreline oscillations of 70–100 m, while comparison with camera-derived shorelines yielded RMSE values of 3.9–9.6 m. At the same site, agreement between GenCade- and CoastSat-derived shoreline-change rates was strong (R2 = 0.986; RMSE = 0.029 m/year). Hydrodynamic simulations further show stronger and more heterogeneous nearshore circulation under winter east-northeast waves than summer southeast waves. The results demonstrate a robust and scalable framework for identifying shoreline-change hotspots and interpreting seasonal shoreline response on monsoon-dominated coasts.