Evaluating and predicting coastal shoreline changes in the Doi Duong - Phan Thiet beach area by remote sensing and GIS technology

Abstract

Abstract Assessing the shoreline variability is paramount in understanding the erosion and coastal accretion processes. The potential impact of erosion on coastal communities, particularly in coastal regions, amplifies the vulnerability to coastal disasters. In this study, Landsat satellite imagery captured from 1990 to 2022 was utilized, in conjunction with Geographic Information System (GIS), to scrutinize alterations in the shoreline of Doi Duong Beach - Phan Thiet. The satellite images were independently processed using aspect-ratio methods and thresholding techniques to determine the prevailing condition of the coastline. The rate of shoreline change was quantified using the DSAS tool. The investigation’s findings reveal a dynamic interplay between erosion and accretion, with accretion dominance explicitly evident within the areas surrounding the Ca Ty - Phu Hai river mouth. The average annual shoreline change rate is 27.1 m/yr for the Ca Ty River mouth and 16.5 m/yr for the Phu Hai River mouth. The most significant disparity between the recorded coastline in 1990 and 2022 measures 868 m. Additionally, the projections for the coastline until 2032 indicate that accretion remains the dominant process. This research shows that combining geospatial techniques and numerical models is a reliable way to study shoreline change trends.