Geospatial analytics for multi-decadal morphodynamics along Gwadar coastal zone

The identification of morphological changes in coastal areas plays a fundamental role in assessment of their spatio-temporal evolution. The focus of this research is to analyze the morphodynamic evolution of shoreline, built-up areas, and vulnerability assessment of Gwadar coastal zone. Using Landsat data, from 1987 to 2021, shorelines were extracted and both long and short-term shoreline changes were assessed in a GIS environment. The results indicate high accretion and sediment entrainment due to anthropogenic developments in Eastern and Western zones. Moderate to high erosion was observed in Eastern zone, whereas, only moderate erosion was observed in the Western zone. The values of greatest retreat and advance along the shoreline of -65.67 m and 827.9 m respectively were recorded in the Eastern zone. The dominant factor of coastal evolution was anthropogenic, augmented by an increase of 13.86% in built-up area. Short-term analysis revealed that erosion and accretion dominated intermittently, with greatest erosion observed during 1994–2001, while, highest accretion occurred from 2001–2007. Furthermore, results of coastal vulnerability assessment indicate that about 15.22% of shoreline consisting of sandy formations is highly vulnerable to hazards. In conclusion, integrated approaches using remote sensing and spatial analysis represent a significant framework for long-term synoptic monitoring of coastal areas.