Abstract/Summary

The compounding effects of climate change and urbanization cause Urban Heat Island and more frequent heatwave events, bringing heat-related health risks to city dwellers. Enhancing thermal resilience is crucial for improving the abilities of the built environment and humans to mitigate and adapt to urban overheating and requires integrative efforts in Social-Ecological-Technological Systems (SETS) strategies. However, it is not clear how humans interact with the urban environment to design thermally comfortable spaces, to what extent they can adapt to perceived outdoor thermal comfort, and what effective strategies can be formulated. Therefore, the overarching aim of this research is to investigate mechanisms and strategies for enhancing thermal resilience of the built environments within SETS dimensions, focusing on both human thermal adaptation and the role of urban design in mitigating the adverse effects of extreme heat events. A mixed methods approach is conducted for a better understanding of the complex essence of thermal resilience in China and the UK contexts. Major contributions and key findings involve: First, human-urban interaction and adaptation mechanisms for thermal resilience are constructed. The processes contain three parts: human thermal adaptation to comfort, design scenarios including Green Infrastructure (GI), urban canyons, and building stock, as well as key driving forces from SETS. Second, thermal resilience indicates that people living in a hot climate for a long period can endure more heat in outdoor spaces during heatwaves. People actively participate in various behavioural adaptation measures rather than passive recipients of thermal environments. Protective measures against heatwaves also need to be provided for pedestrians, including more shaded places with efficient ventilation design for sheltering. Third, the radiation impact of shading scenarios on outdoor thermal comfort was thoroughly evaluated by simulations. GI and artificial shading through trees and sun sails respectively can significantly lower mean radiant temperature. These shading strategies suggest being integrated into urban design to mitigate heat stress and support human adaptation. Finally, thermal resilience can be understood as a technology-oriented concept and its constituents contain mutual influences. Strategies for policy development and planning as well as low-carbon building standards and codes are of priority. The identified interventions and strategies can practically assist policymakers to mitigate overheating risks and facilitate urban heat adaptation.