Evidence of coastal erosion in Moree and Cape Coast Metropolis using GIS and Remote Sensing

Abstract

Coastal zones are dynamic environments undergoing rapid morphological changes due to natural processes and human activities. This study evaluates shoreline alterations along the Moree and Cape Coast coastlines in Ghana, using the Digital Shoreline Analysis System (DSAS) integrated within a Geographic Information System (GIS) environment. Landsat satellite imagery from 2007, 2011, 2017, and 2024 was preprocessed and analyzed to extract shoreline positions. Four statistical techniques: End Point Rate (EPR), Linear Regression Rate (LRR), Net Shoreline Movement (NSM), and Shoreline Change Envelope (SCE) were applied to assess erosion and accretion trends. Results indicate that 70.3 % of the shoreline is currently experiencing erosion, with an average retreat rate of –0.9 m/year. Illegal sand mining emerged as the predominant anthropogenic driver of coastal degradation, based on field interviews. The study underscores the efficacy of DSAS in detecting shoreline dynamics and provides actionable insights for coastal zone management and policy interventions.