[en] Urban configuration and climate change both impact the local climate conditions and outdoor thermal comfort. This study examines summer Urban Heat Island (UHI) intensity and thermal discomfort in the Brussels region using a data-driven approach based on continuous field measurements collected from July to September 2022. The characterization of near-surface UHI revealed strong temperature elevations, reaching up to 19°C between four urban sites and one suburban area during several periods. Based on the Humidex index, these UHI intensities caused significant heat stress, affecting people’s thermal comfort, resulting in more than 38 hours of intense discomfort across 60 days in summer 2022. Within a period of less than three months, three heat waves occurred in proximity, which also amplified UHI by 2°C at nighttime and 1°C during the day compared to normal climatological days. Results led to a real characterization of UHI levels and their effects on one of the EU cities. By identifying UHI hotspots and thermal discomfort zones, urban planners can prioritize interventions such as increasing green spaces, implementing cool roofs, and developing an early warning system to protect vulnerable populations during extreme heat periods.
Disciplines :
Architecture
Author, co-author :
Matallah, Mohamed Elhadi ; Université de Liège - ULiège > Département ArGEnCo > Techniques de construction des bâtiments
Boulkaibet, Aissa
Arrar, Fawzi Hicham ; Université de Liège - ULiège > Urban and Environmental Engineering
Wang, Tianyi ; Université de Liège - ULiège > Urban and Environmental Engineering
Amaripadath, Deepak ; Université de Liège - ULiège > Urban and Environmental Engineering
Ahriz, Atef
Amer, Mohamed ; Université de Liège - ULiège > Département ArGEnCo > Techniques de construction des bâtiments
Attia, Shady ; Université de Liège - ULiège > Département ArGEnCo > Techniques de construction des bâtiments
Language :
English
Title :
Data-driven characterization of urban heat island intensity, heat wave, and heat stress interactions in Brussels: A field measurement study
Publication date :
15 December 2025
Journal title :
Sustainable Cities and Society
ISSN :
2210-6707
eISSN :
2210-6715
Publisher :
Elsevier
Volume :
135
Pages :
106974
Peer reviewed :
Peer Reviewed verified by ORBi
Development Goals :
11. Sustainable cities and communities 13. Climate action
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