Combining the WRF model and LCZ scheme to assess spatiotemporal variations of thermal comfort in Shenzhen's built-up areas

• Incorporating LCZ map into WRF substantially enhances wind speed simulation accuracy. • Southwest Shenzhen has the worst thermal comfort due to high temperatures and low winds. • Higher development intensity of built-up LCZ correlates with poorer thermal comfort. • Intra-LCZ thermal comfort varies significantly with spatiotemporal conditions. Applying the local climate zone (LCZ) scheme is effective for guiding the urban morphology to enhance outdoor thermal comfort. Previous studies have extensively explored thermal comfort in built-up areas and their inter-LCZ variations by applying temperature attributes. However, the combined effects of other factors (humidity and wind speed) have received little attention, and intra-LCZ thermal comfort variations are not fully understood. This study aimed to assess spatiotemporal variations in thermal comfort across built-up LCZs based on multiple meteorological factors. We incorporated the Weather Research and Forecasting model with the LCZ scheme and calculated the net effective temperature using simulated air temperature, relative humidity, and wind speed. Inter-LCZ and intra-LCZ thermal comfort variations were analyzed using spatial autocorrelation and statistical methods. The study was conducted during both dry and wet seasons in the subtropical city of Shenzhen, China. The results revealed that 1) the southwestern area experienced the poorest thermal comfort during the wet season owing to high temperatures and low wind speeds; 2) significant inter-LCZ thermal comfort differences existed within the same season, with higher development intensity correlating to poorer thermal comfort; and 3) intra-LCZ thermal comfort varied across spatial locations and fluctuated with the season and time of day.