A systematic review of soundscape and thermal comfort interactions in hot-arid environments

In hot-arid cities, the soundscape of public space has been an underutilized element of urban design, often treated as a secondary consideration relative to visual appearance. This neglect contributes to thermal discomfort and the underutilization of urban outdoor public space, a problem that is especially prevalent in the Gulf region, where the lack of shade renders the outdoor public space uninhabitable for a significant portion of the year. To fill this gap, this study aims to conduct a PRISMA-guided systematic review of 22 peer-reviewed studies (2005–2025) that focus on the soundscape design, outdoor thermal comfort, and urban space quality in hot-arid and thermally comparable environments. Thematic content analysis reveals five theme areas that are interlinked: (i) integrated thermal-acoustic design, (ii) the function of green and blue infrastructure in soundscapes, (iii) multisensory perception and psychological restoration, (iv) problems and concerns with human-centered soundscape planning, and (v) the impact of urban morphology on microclimate and sound propagation. The synthesis shows that, under moderate thermal stress conditions, positive soundscapes (created with natural sounds and green-blue infrastructure) can positively influence the thermoceptive comfort perception and decrease the perceived heat stress as well as encourage active use of public space. These benefits, however, are limited, becoming much less pronounced in extreme heat and are predominantly psychological and cognitive in nature, operating through individual appraisal rather than direct sensory response. Based on these findings, the paper introduces the Integrated Thermo-Acoustic Planning (ITAP) Framework as a multi-scalar, evidence-based design model and a persona-based Interdisciplinary Implementation Toolkit. These outputs, combined, offer context-specific guidelines for the design of walkable, thermally comfortable, and acoustically restorative public spaces to support the Saudi Arabia Vision 2030 Quality of Life Programme.