A comprehensive review of outdoor thermal comfort in urban areas: Effective parameters and approaches

Increased urban air temperature considerably affects the health, comfort and consequently the quality of life in urban spaces. Urban design and planning studies, therefore, face an increasing challenge as they aim to improve Outdoor Thermal Comfort (OTC) and microclimate conditions of urban environments. Analysing OTC is more challenging when compared to indoor thermal comfort since a wider range of interrelated parameters exists in outdoor environments. Therefore, this research aims to classify urban studies that investigate OTC by conducting a comprehensive review based on key metrics such as approaches taken, methodologies and spatial and temporal scales. By extracting the key findings, this research forms an integrated framework of these metrics that presents a thorough view of the OTC concept in the context of climate-sensitive studies. Furthermore, this research elaborates on the main two groups of parameters affecting OTC including environmental and human-based parameters. Exploring the intricate inter-relationships of these two groups of parameters clarifies their contribution to OTC. Results of this study help architects and urban planners to improve their climate-sensitive strategies and support the decision-making process by providing a comprehensive perspective about different aspects of OTC. Finally, recommendations for future research are outlined.