Harnessing street shade to mitigate heat stress: An in-situ parallel investigation under extreme heat conditions in tropical Singapore.

Autor: Xu L; Future Cities Laboratory Global, Singapore-ETH Centre, Singapore; Sustainable Design Group, Department of Architecture, University of Cambridge, Cambridge CB2 1PX, UK., Bardhan R; Sustainable Design Group, Department of Architecture, University of Cambridge, Cambridge CB2 1PX, UK; CARES Cambridge Centre for Advanced Research and Education in Singapore, Singapore, 138602. Electronic address: rb867@cam.ac.uk., Mei H; Nanjing Foreign Language School, China., Gopalakrishnan S; Future Cities Laboratory Global, Singapore-ETH Centre, Singapore., Zheng X; City University of Hong Kong, Hong Kong., Schroepfer T; Future Cities Laboratory Global, Singapore-ETH Centre, Singapore; Singapore University of Technology and Design, Singapore. Electronic address: thomas.schroepfer@sec.ethz.ch.
Jazyk: angličtina
Zdroj: The Science of the total environment [Sci Total Environ] 2024 Dec 13; Vol. 958, pp. 177864. Date of Electronic Publication: 2024 Dec 13.
DOI: 10.1016/j.scitotenv.2024.177864
Abstrakt: In the face of global rising temperatures and excessive urban heat, developing effective heat mitigation strategies has become increasingly urgent. Street shade, a typical cooling shelter for urban dwellers, has been primarily investigated for outdoor thermal comfort but not extensively under extreme heat conditions. This study explores the cooling efficacy of diverse street shade types in mitigating urban heat, thereby facilitating cities and their residents' adaptation to climatic shifts. We conducted in-situ measurements during an extremely hot afternoon, measuring thermal and visual environments across 20 pairs of parallel sites (sunlit vs. shaded) in a high-density district of tropical Singapore. Subsequently, we analyzed thermal comfort, represented by the Universal Thermal Comfort Index (UTCI), heat stress risks, and view factors of the sky, greenery, and buildings, and their interaction with heat stress relief. Our findings highlight three key points: Firstly, all street shade types improved outdoor thermal conditions, with average decreases of 0.8 °C in air temperature, 10.0 °C in mean radiant temperature, and 3.1 °C in UTCI. Secondly, street shade generally reduced heat stress severity by 20 % in the 'very strong heat stress' category and 12 % in the 'strong heat stress' category. Thirdly, the cooling efficacy of street shade was not solely dependent on changes in any single view factor. The results demonstrate the significant cooling benefits provided by street shade during extreme heat conditions. This study not only underscores the crucial role of street shade in mitigating heat stress but also offers valuable guidance to urban planners and designers in creating more liveable, sustainable, and climate-adaptive cities.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)
Databáze: MEDLINE
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