Comparison of urban physical environments and thermal properties extracted from unmanned aerial vehicle images and ENVI-met model simulations

Identifying the thermal properties of urban areas and integrating these properties into spatial planning is essential for sustainable development. Continuous and efficient improvements of urban thermal environments require novel studies, which are limited to date. This study addresses this gap by presenting a comparison of the physical environments and thermal properties of an urban area (Changwon National University, Gyeongsangnam-do, South Korea) based on unmanned aerial vehicle (UAV) images and ENVI-met model simulations. We predicted the thermal environment of the study area using UAV images and explored the potential application of UAVs in spatial planning. The comparison revealed that the coefficient of determination (R2) between mean radiant temperature (Tmrt) values simulated by the ENVI-met model and predicted from UAV images was 0.168–0.320. Significant differences were observed in shaded areas and vegetated regions with tall trees, where UAVs encountered difficulties in collecting accurate information due to obstructed visibility. The discrepancies between the simulated and predicted Tmrt values highlight the limitations of UAVs in capturing data in shaded and densely vegetated areas, as well as disparities in the physical environments determined by the two methods. Despite these limitations, UAVs can be valuable tools for urban and environmental planning. Future advancements addressing these limitations may enable UAVs to efficiently diagnose urban thermal environments and guide improvement efforts.