IDENTIFICATION OF SHORELINE CHANGES USING DIGITAL SHORELINE ANALYSIS SYSTEM (DSAS): A CASE STUDY OF KARACHI COAST, SINDH, PAKISTAN

Abstract

Shorelines are a very important feature of the coast. It is continuously changing due to natural activities like waves, and currents, and anthropogenic activities like construction. These changes cause morphological changes to the coast due to erosion and accretion. In case of erosion, coasts are at risk. For this purpose, Shoreline Changes were calculated by using the Digital Shoreline Analysis System (DSAS) for the last two decades at the Karachi coast. Shoreline changes showed both erosion (at bin Qasim town) and accretion (at Korangi town) but erosion dominated the entire coastline, especially in 2015. Shoreline Change Envelope (SCE), Net Shoreline Movement (NSM), End Point Rate (EPR), and Linear Regression Rate (LRR) are 427.76 m, -46.02 m, -3.22 m/yr. and -2.16 m/yr. respectively in the last two decades.