Toward obsolete housing: A complementary explanation of increasing coastal vulnerability

This paper explains the process of increasing coastal vulnerability in response to coastal flooding, from the property market viewpoint. Rooted in knowledge about housing submarket-based neighborhood change, this study adds new understandings of how housing obsolesces influence vulnerability following rapid land use changes, which are currently studied as a new exposure by many researchers. We employ six years of house sales transaction data (n = 1,029) in a spatial data-driven delineation with k-means, through which the submarket shift can be visualized. This approach addresses weaknesses in the existing methods to measure neighborhood change. We find that second-hand houses purchased by low-income people tend to cluster close together in newly formed submarkets in at-risk areas creating submarkets for western-inner city and distressed properties. Our data series also show that the geographical growth of the submarket for distressed properties is expanding, creating further blight in the submarket for western-inner city. Consequently, the submarket for distressed properties tends to transform into an area characterized by substandard housing conditions or slum living. Bearing in mind that the consequences of a flood will cover a wide range of issues, such as the future of public services, and the welfare of citizens in general, disaster risk management is fundamental to socio-economic development of a country. This study can enrich discussions around housing vulnerability and neighborhood change and support the current debate over spatial adaptation and climate change.