A review of multi-scale modelling, assessment, and improvement methods of the urban thermal and wind environment

The urban thermal and wind environment (UTWE) has become a major concern in urban planning design. Consideration of the UTWE involves steps of modelling, assessment, and improvement on multiple scales. However, the method specifications of each step on different scales are unclear, and a comprehensive review of relevant studies is thus required. On this basis, the modelling, assessment, and improvement methods of the UTWE are comprehensively reviewed according to their applicable scales. The review indicates that the scale is systematically considered by studies of the UTWE modelling and improvement, but not by studies of UTWE assessment. On the meso-scale, the UTWE of plot units are usually evaluated in isolation and the interactions among them are neglected. Studies of the UTWE improvement cover urban morphology, urban green and blue infrastructure, and urban materials, but some of their conclusions contradict each other. Current UTWE assessments cannot directly guide the selection of proper improvement strategies. In the future, studies of the UTWE improvement may be based on urban typologies such as the Local Climate Zone, and the data-driven approaches provide an opportunity to link the results of UTWE assessment and the corresponding improvement strategies.