Assessment of three-dimensional distribution of thermal environment: A field study on outdoor spaces of academic building in severe cold region

In the context of rapid urbanization, challenges like the urban heat island effect have significantly reduced the efficiency and usability of outdoor spaces, especially in cold regions where maximizing summer usage of outdoor areas holds more value. This study aims to explore the potential of utilizing roof spaces at various heights of campus buildings as an effective supplement to existing public spaces, with the objective of alleviating crowd density and enhancing thermal comfort. The research involves the collection of data regarding the physical characteristics of outdoor environments at different elevations, as well as student perceptions of thermal comfort., It also ranks meteorological factors that influence thermal comfort at varying heights, and identifies suitable evaluation indicator. Notably, a discernible trend in the variation of thermal neutral temperature with elevation is observed, alongside variations in thermal comfort ranges at different heights. Specifically, the neutral temperature recorded at 1.5 meters during the summer was 16.40°C, at 3.5 meters it was 19.09°C, at 5.5 meters it was 18.40°C, and at 13.5 meters it reached 21.93°C. Additionally, the findings indicate that female participants generally experience broader intervals of thermal neutral temperatures compared to their male counterparts. Furthermore, students from southern regions (south of 34°N) exhibit greater sensitivity to temperature changes at elevated locations compared to those from northern regions (north of 34°N), while northern students show more sensitivity near ground level. • The importance of considering both temporal and spatial variations in urban microclimates when assessing temperature patterns. • UTCI is identified as the optimal indicator for evaluating outdoor thermal conditions at different elevations in summer. • The outdoor thermal neutral temperature exhibits an increasing-decreasing-increasing trend at different heights of the building. • Individual differences are important factors, including gender and varying thermal experiences.