Risk mapping of Indian coastal districts using IPCC-AR5 framework and multi-attribute decision-making approach

• Published in: Journal of environmental management 2021-09, Vol.294, p.112948-112948, Article 112948
• Main Authors: Malakar, Krishna, Mishra, Trupti, Hari, Vittal, Karmakar, Subhankar
• Format: Article
• Language: English
• Subjects: Cyclone; Exposure; Hazard; Index; Risk; Vulnerability
• ISSN: 0301-4797; 1095-8630
• DOI: 10.1016/j.jenvman.2021.112948

Strategic location of coastal areas across the world causes them to be prone to disaster risks. In the global south, the Indian coast is one of the most susceptible to oceanic extreme events, such as cyclones, storm surge and high tides. This study provides an understanding of the risk experienced (currently as well as back in 2001) by the districts along the Indian coastline by developing a quantitative risk index. In the process, it attempts to make a novel contribution to the risk literature by following the definition of risk as a function of hazard, exposure and vulnerability as stated in the most recent (Fifth) assessment report of the Intergovernmental Panel on Climate Change (IPCC). Indicators of bio-physical hazards (such as cyclones, storm surge, tides and precipitation), and socio-economic contributors of vulnerability (such as infrastructure, technology, finance and social nets) and exposure (space), are combined to develop an overall risk index at a fine administrative scale of district-level over the entire coastline. Further, the study employs a multi-attribute decision-making (MADM) method, Technique for Order Preference by Similarity to Ideal Solution (TOPSIS), to combine the contributing indicators and generate indices on hazard, exposure and vulnerability. The product of these three components is thereafter defined as risk. The results suggest that most districts of the eastern coast have higher risk indices compared to those in the west, and the risk has increased since 2001. The higher risk can be attributed to the higher hazard indices in the eastern districts which are aggravated by their higher vulnerability index values. This study is the first effort made to map risk for the entire coastline of India — which in turn has resulted in a new cartographic product at a district-scale. Such assessments and maps have implications for environmental and risk-managers as they can help identify the regions needing adaptive interventions. [Display omitted] •Eastern coast of India is relatively more risk-prone than the west coast.•Greater risk in the east is a combined result of higher hazard and vulnerability.•Important coastal cities of India have greater exposure to hazards.•Vulnerability of coastal districts has declined since 2001.•Risk on the east coast has increased since 2001.