Assessment of social vulnerability to natural hazards in South Korea: case study for typhoon hazard

Most often, disaster vulnerabilities are discussed from the perspective of developing countries. This paper extends the argument using an example from a developed country, by focusing on the South Korea during the period from 2009 to 2013. South Korea has suffered from a range of natural hazards throughout its history, and experienced one to three typhoons per year on the average, with most events occurring in August and September. Since 1945, around 17 major typhoons have directly affected South Korea. This study used Self Organizing Map (SOM) and Social Vulnerability Index (SoVI) for data analysis in terms of the number of social vulnerability variables and samples. The dataset used for social vulnerability analysis consisted of 12 variables, which were adopted and adapted from the research literature related to Hurricane Katrina. However, some of the variables employed in this study might be more or less redundant, necessitating the removal of redundant variables from the accurate SOM analysis. Overall, during the period from 2009 to 2013, the variables of ELDRY (elderly population), POPDNSTY (population density), and DISBLD (disabled population) are the dominant variables which frequently appear as the two top variables that lead to an increase in social vulnerability. According to the findings related to the social vulnerability index, nearly half of all regions have positive values, which are categorized as highly vulnerable. As there are growing concerns on the adequacy of using the concept of vulnerability to address loss and damage, an additional approach was attempted by using typhoon hazard examples, e.g. Typhoons Dianmu and Kompasu of 2010, Typhoon Muifa of 2011, and Typhoon Sanba of 2012. Additional factors such as shortest distance from the typhoon track and maximum wind speed were considered together to obtain the weighted correlation between them. Based on the process of this study, SOM has an essential benefit in evaluating SoVI.