Shoreline Change Detection and Future Prediction of Sundarban Delta Using Remote Sensing Data and Digital Shoreline Analysis System

The present study focused on shoreline change detection and future prediction of the Sundarban Delta using a digital shoreline analysis system with the help of multispectral satellite images and geographic information systems. In this study, five multi-temporal Landsat satellite data (1975, 1990, 2000, 2010 and 2020) were used for the change detection of five islands (Bakkhali, Lothian, Bulchery, Mayadwip and Baghmara) in the Sundarban Delta. A Canny edge detection technique was applied to the satellite images to extract the shoreline. Four statistical methods were used to quantify the rate of variation of shoreline in terms of erosion and accretion, namely shoreline change envelope (SCE), net shoreline movement, end point rate (EPR) and linear regression rate (LRR). The results revealed that more than 80% of transects in the southern positions of each island gradually eroded. The SCE parameter result shows the maximum changes in shoreline obtained at 2715 m during 1975-2020. The highest rate of shoreline changes was achieved 168.2 m/yr and 84.1 m/yr by the EPR and LRR parameters, respectively. It also observed that all transects of Baghmara Island gradually eroded. A Kalman filter is used to predict the future prediction of the shoreline. The outcome shows the southern edge of each island may shift toward the land surface. It is expected that the outcome of this study will help to understand the possible risks of future changes in the shoreline that will require the country to establish planning and management strategies for its very significant southern shoreline.