An analytical framework for assessing heat vulnerability in urban thermal environmental planning

Due to global climate change, the frequency and intensity of heat-related disasters in cities are continuously increasing. Intraurban heat vulnerability may vary according to the spatial conditions of a detailed area, and it is important to consider spatial characteristics when planning to create a comfortable urban thermal environment. However, in terms of urban planning, analytical frameworks of heat vulnerability that systematically organize and define spatial indicators associated with the thermal environment are still rarely used. Thus, this study proposes an analytical framework of heat vulnerability that synthesizes the related spatial indicators of three consecutive stages: causal factors, outcome issues, and response strategies. We analyzed and reviewed various related studies focusing on causal urban indicators, heat-related urban issues and various response approaches. We identified various thermal environment-related indicators and systematically classified them according to their definitions (i.e., static or dynamic) and characteristics (i.e., the environment, infrastructure and humans). Finally, an analytical framework of heat vulnerability is introduced to examine the intraurban thermal environment. The proposed framework consists of 14 attributes for the three main stages of heat vulnerability we defined. This framework can contribute to decision-making in the urban planning process to ensure a comfortable intraurban thermal environment. •Heat vulnerability varied by region within a city.•Spatial factors affecting the thermal environment were systematically organized.•A comprehensive framework that described the heat vulnerability concept was proposed.•Derivation of heat vulnerability response plans connectable to the proposed framework.