Assessment of coastal vulnerability along Bangladesh coast using analytical hierarchical process (AHP)

Abstract

Situated within one of the world’s largest basins, the Ganges-Brahmaputra-Meghna (GBM), Bangladesh frequently experiences natural disasters due to itsgeomorphological setup. Situated along the southern edge of Bangladesh and open to the Bay of Bengal, this coastline experiences regular and diverse natural disasters. Owing to climate change, the coastline of Bangladesh is expected to become more vulnerable over time. Consequently, it is essential to understand the spatio-temporal dimensions of vulnerability and reinforce the resilience of coastal communities. This study utilized Remote Sensing and GIS techniques in combination with Multi-Criteria Decision Making (MCDM) and the Analytical Hierarchical Process (AHP) to establish a Coastal Vulnerability Index (CVI) of Bangladesh coast. AHP was conducted in ArcGIS version 10.5, using two geological parameters, five physical process variables, and three socio-economic parameters. Several thematic maps were created for each parameter using ArcGIS and reclassified according to vulnerability rankings. Ultimately, a CVI was developed, categorizing vulnerability into three classes: moderately vulnerable, vulnerable, and highly vulnerable. Results indicate that approximately 70 % of coastal areas are vulnerable, while 29 % area fall within moderate to high vulnerability zones. Around 1 % of the area in Khulna District, Satkhira District, and Char Fasson of Bhola District is classified as highly vulnerable. Considering the coastline, 28 km is highly vulnerable, 315 km moderately vulnerable, and 196 km vulnerable. This study will provide valuable insights for government officials, local administrators, coastal planners, and decision-makers in developing a risk management plan for sustainable long-term coastal management.