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Local Climate Zones (LCZs) classification of urban area under World Urban Database and PortalTool (WUDAPT) framework has amassed about 100 regions’ LCZ catalog by an international collaborationof researchers. With Landsat 8 (L8) being the current standard of imagery for most of the LCZ classificationprocess, the question of ability to distinguish LCZs from the spectral range of L8 imagery need to be answered.Using sample of training areas, Jeffries-Matusita distance are computed as the measure of separability toinvestigate if any pairs of LCZ class consistently show similar spectral signature and it’s utility to predict thequality of final LCZ classification.

Urban form play an important role in influencing building energy use. Previous empirical studies on urban form and building energy mostly represented urban form as separate indicators of form components and socioeconomic conditions. However, urban form is a complex system that consists of different components and interactions. Thus, simply considering urban form as an aggregation of their components and properties often suffers from strong correlations among these factors and the confounding effect as in previous studies. To better understand the energy performance of complex urban form, this study identifies urban form typologies in Seoul using unsupervised learning and examines the energy performance of those typologies. The Gaussian mixture model (GMM), a widely used clustering method, is adopted to identify 16 urban form typologies based on 10 common urban form and population distribution factors. Electricity use and gas use in different typologies in 2019 are collected and compared using the Brown Forsythe ANOVA and Games Howell post hoc test. Results suggest that urban form typologies reflect energy efficiency to a certain degree, and the difference in energy efficiency across urban form typologies is more significant in gas than in electricity because of occupant behavior differences in their use. Among the urban form typologies, high-rise high-density urban form type is the most efficient, and the high-rise mixed type is the least efficient. The findings from this research could help urban planners and designers to understand the relationship between complex urban form and building energy better to support planning and design toward an energy-efficient urban form.