Identification of the coastal hazard zone between the areas of Rasulpur and Subarnarekha estuary, east coast of India using multi-criteria evaluation method

Abstract

An increasing number of coastal hazards such as cyclones, tsunami and coastal erosion are the consequences of global climate change, creating an immense impact on the coastal habitat and coastal ecosystem. The study area (Subarnarekha to Rasulpur estuary) part of the Bay of Bengal is under a potentially vulnerable condition to coastal erosion. The area has witnessed cyclones during the pre-monsoon and retreat or post-monsoon season. The present study aimed to assess the coastal hazard zone (CHZ) along the 70 km coastal stretch within 119.49 km2 area near the shoreline. The present study follows the multi-criteria evaluation (MCE) method to identify the CHZ. Multi-resolution satellite images and ASTER DEM image are used to complete the study. Six influencing factors are applied in method MCE such as coastal slope, aspect, distance to river and estuaries, land use/land cover, shoreline change rate and distance to shoreline. Various GIS techniques are used to prepare the raster layer map from these six influencing factors in Arc GIS 10.3 software. Finally, weighted overlay analysis was implemented to obtain the CHZ map from multi-criteria, assigning the weights according to their vulnerability. Five zonation classes are selected based on their vulnerability rank: very high, high, moderate, low and very low hazard zone. The acquired result will enable identification of vulnerable and hazard-prone areas and will also be helpful for coastal management and to decision makers for future implementation in coastal conservation.