Influence of land use and cover on storm surge induced coastal flooding in the sundarbans during cyclone Amphan

The coupled hydrodynamic models are widely used in predicting storm surges and the extent of inundation along coastal regions and have tremendous applications in coastal management and vulnerability assessment. Land use and land cover (LULC) are essential in storm surge and related coastal inundation, as they impact the water flow velocity. Few studies have reported LULC within coupled hydrodynamic models to study storm surges. To understand the impact of LULC inclusion in a coupled hydrodynamic model (ADCIRC + SWAN), a very severe cyclone, Amphan, which has crossed the Sundarbans region of the West Bengal coast, is considered. This study considered two LULC data sets of MODIS and SENTINEL. The results have shown significant changes in the storm surge and extent of inundation due to different land classes. The coastal regions consist of built-up, forest and crop land, which experience a drastic reduction compared to flooded vegetation regions. MODIS LULC data reduced inundation by 10–12% while SENTINEL data showed greater reductions of 20–25%, underscoring the value of high-resolution LULC in flood modelling. The present study results provide potential information for coastal flood management, improved storm surge prediction and subsequently vulnerable assessment of coastal regions.