Multi-hazard risk assessment of coastal municipalities of Oaxaca, Southwestern Mexico: An index based remote sensing and geospatial technique

Multi-hazard risk assessment (MHRA) modelling was done for the coastal region of Oaxaca in the south-western coast of Mexico that is vulnerable to diverse high-risk multiple natural hazards. The study aimed to evaluate the MHRA of Oaxaca by combining both vulnerability and hazard variables using various indices. The Integrated Coastal Vulnerability Index (ICVI) was calculated by combining multiple sub-index parameters such as Coastal Characteristics (CCSI), Coastal Forcing (CFSI) and Socio-economic factors (SESI). CCSI results indicated that around 20.6% of the coastal municipalities are in a very high vulnerability category that covers the north-western and south-eastern region of Oaxaca, while CFSI indicated 13.45% of the area as very high vulnerability due to the increased impacts of cyclone density and rainfall distribution in the mountainous region. The ICVI indicated that the percentage of area in each class was represented as very low (15.43), low (28.96), moderate (31.67), high (17.11) and very high (6.83). The multi-hazard assessment of inundation scenarios showed that 48.28% of Heroica Ciudad de Juchitán de Zaragoza is under the class of high-very high vulnerability. MHRA map provided a detailed description of population and household exposure at different risk categories, where 70–98% of population and household are categorized as high-very high risk in San Mateo del Mar, San Francisco del Mar and Salina Cruz municipalities. Hence, this type of study could be applied for different regions around the world for integrating mitigation plans in the reduction of the potential impacts of multiple coastal hazards.