Impact of Spatial Characteristics of Deteriorated Low-Rise Residential Areas on Urban Microclimate

Purpose: This study examines the effects of spatial structural characteristics on air temperature in deteriorated low-rise residential areas (DLRA) in Gwangju, South Korea, where heat vulnerability is pronounced under extreme summer heat conditions. Method: Independent variables included building coverage ratio, floor area ratio, number of building stories, building age, road ratio, green-space ratio, normalized difference vegetation index (NDVI), normalized difference built-up index (NDBI), elevation, and slope; wind speed and relative humidity were included as control variables. Air temperature at 14:00 on the hottest day of 2024 was analyzed using ordinary least squares (OLS), a spatial lag model (SLM), and a spatial error model (SEM). Result: SEM was selected as the best-fitting model, and its estimates were interpreted. Building age and the number of stories had significant negative effects on air temperature. NDVI was negatively associated with air temperature in OLS and SLM, but became significantly positive in SEM, indicating that estimated effects can change once spatial dependence is accounted for. The findings suggest that, in DLRA, heat-mitigation strategies should consider not only the amount of green space but also vegetation type, spatial arrangement, and shade provision. In particular, expanding shade through tree planting and shading structures should be prioritized as a practical strategy for improving thermal conditions in space-constrained residential areas.