Assessment of the impact of urban block morphological factors on carbon emissions introducing the different context of local climate zones

Abstract

Understanding the relationship between urban block morphology and carbon emissions is essential for developing effective low-carbon strategies, as it determines the buildings’ contextual form and microclimate, substantially affecting buildings’ energy demand. However, traditional indicators or typological methods define the buildings contextual form only through geometric features, which cannot fully reflect the complexities of urban environments and lack a unified spatial framework, hindering the establishment of standardized urban form-carbon emission mapping relationships. This study examines the compound effects of urban morphology on carbon emissions using a linear mixed-effects model, incorporating Local Climate Zones (LCZ) as the contextual form. The results demonstrate that LCZ explains 65.26% of the variation in carbon emission levels across blocks and significantly influences the relationship between urban morphology and carbon emissions. LCZ2 is one of the optimal low-carbon block morphological prototype. Building shape factor, height-to-width ratio, floor area ratio, building coverage ratio, and the facade area index are key design indicators that affect carbon emissions, with additional random effects as LCZ type changes. These findings suggest that the LCZ framework can help elucidate the relationship between block urban morphology, buildings contextual form and carbon emissions, and can be used to develop climate-responsive, low-carbon urban planning solutions.