Assessing urban heatwave conditions using a three-dimensional zone-based air temperature framework

Climate change is rapidly intensifying the frequency and severity of urban heatwaves, presenting profound risks to urban resilience and public health. Urban heatwaves are inherently three-dimensional phenomena, shaped by complex interactions between building morphology, surface characteristics, and air exchange processes within the urban canyon. Conventional evaluation methods, which primarily rely on two-dimensional surface temperature data or isolated point-based measurements, often fail to capture the nuanced micro-scale temperature variations across diverse spatial dimensions and vertical profiles. This study introduces a three-dimensional, zone-based air temperature framework as an effective alternative for assessing heatwave conditions within urban environments.
The framework operates by first simplifying complex building geometries into structured, representative forms to optimize the simulation process. Based on these simplified building configurations, the urban exterior space is then partitioned into automated 3D zones. The model tracks temperature dynamics by calculating air exchange rates between these zones and convective heat transfer from urban surfaces, such as walls and rooftops. Furthermore, the framework allows for the simulation and visualization of various adaptation scenarios, such as the implementation of green walls. This allows users to virtually implement different technologies and observe how they might alter local temperature patterns across various heights and spatial locations. By offering a middle ground between simple 2D maps and complex simulations, this approach helps planners create better heat-reduction policies and improves our fundamental understanding of urban resilience for a sustainable future.