Identifying the Gaps in Cyclone Vulnerability Mitigation in the Indian Sundarban Using AHP Based Multi Criteria Decision Analysis (MCDA) and GIS Techniques: Tool for the Policy Makers

The low-lying coastal Sundarban is one of the prominent landfall area of tropical cyclones in this region, causing significant environmental and socio-economic disruptions. Spatial cyclone vulnerability assessment is essential to identify its impact on people and fragile ecosystems. This study applied a GIS-based Analytic Hierarchy Process (AHP) to assess the spatial distribution of tropical cyclones in the Indian Sundarban. In the process of this cyclone vulnerability mapping, altogether fourteen spatial components were considered, five each from the physical and social vulnerability and four from the mitigation capacity. Based on each individual factor's proportionate contribution to the cyclone vulnerability, five-point risk classes’ frameworks were created. The study identified a combined physical and social vulnerability map showing most of the coastal community development (CD) blocks like Sagar, Namkhana, Patharpratima, Basanti, Gosaba, and Hingalganj are highly vulnerable to tropical cyclones. Interestingly, while the earlier vulnerability map is being integrated with mitigation capacity, the result is showing that Sagar, Namkhana, Patharpratima, and Basanti have fallen under a low vulnerable zone. This is due to the presence of adequate mitigation capacity and infrastructural facilities in those CD blocks. On the other hand, due to the lack of cyclone shelters and health centers, weak communication facilities, and inadequate infrastructure in the development blocks like Kultali, a large part of Gosaba, Jaynagar I, Jaynagar II, Canning I, Canning II, and small parts of Patharpratima and Hingalganj have fallen under very high to high vulnerable zones. The findings can be applied towards an efficient need assessment tool for the policymakers, to identify where and what kinds of mitigation measures are required.