Urbanisation may have been shown to have no effect on climate change, but some researchers suggest that cities are fully capable of responding to it. Urban Heat Islands (UHIs) represent dense urban areas within cities where the temperature is recorded to be higher than the neighbouring areas or those located in suburbia. Mitigation of UHI effects can help diminish detriments of climate change. This paper sets out to establish UHI mitigation strategies, their effectiveness and resilience to help provide recommendations for application of such strategies in future. Existing literature suggest that UK is facing with growing problem of UHI effects and sustainable development at urban scale can be improved if proportionate measures are taken to mitigate those effects. The lack of guidance for designers and planners with regards to UHI mitigation is also indicated in the literature where trees, shrubs and grass (TSG), use of high albedo materials (HAM) in external building surfaces and urban inland water bodies (UIWB) are identified as effective measures to mitigate UHI. This research identifies and tests resilience and effectiveness of UHI mitigation strategies, using ENVI-met simulations and through Urban Futures Assessment Method (UFAM).Assessed mitigation strategies (TSG, HAM, UIWB) are shown to have a similar level of resilience which could be improved if proper future-proof measures are taken in place. As a result, some practical suggestions are provided to help improve the resilience of tested UHI mitigation strategies in this study.

Cities are major sources of Green House Gas (GHG) emissions and the effects of mass urbanization upon the environment have now become clear. Great opportunities exist within cities for tackling climate change. Urban Heat Island (UHI) effect is a phenomenon where significant temperature difference between inner micro-climates of a city and their neighboring microclimates can be perceived. Mitigation of UHI effects can positively contribute to alleviate detriments of climate change. This research project aims to investigate effective and resilient UHI mitigation strategies and to provide guidance for their application in future. A review of literature indicates that UHI is a growing problem in the UK and that mitigation of such effects would enhance sustainable development at urban scale. The lack of guidance for designers and planners looking into mitigating the UHI effect is also identified. Utilizing ENVI-met simulations and through Urban Futures Assessment Method (UFAM), this research identifies and tests resilient and effective UHI mitigation strategies. Results show that building form, orientation and layout are among the most effective UHI mitigation strategies. Trees, shrubs and grass (TSG), and use of high albedo materials (HAM) in external building surfaces are also indicated as effective measures whose success is dependent on building form. All assessed mitigation strategies (TSG, HAM, UIWB) are shown to have a similar level of resilience which could be improved if properly future-proofed against subsequent changes. Accordingly some practical suggestions are provided to help improve the resilience of tested UHI mitigation strategies.

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This study aimed to investigate urban forms susceptible to heightened heat intensities in the Tokyo Prefecture in Japan. Adopting Landsat 8 data at a pixel resolution of 100 m, local climate zones (LCZ) were identified. LCZs contain urban forms which are primarily defined by building compactness and height. Daytime spatial distribution of land surface temperatures (LST) was provided by MODIS 100 m resolution data from 2013 to 2021. Median LSTs for compact and super high‐rise, high‐rise, mid‐rise, and low‐rise LCZs were 34.4, 35.5, 37.3, and 38.1°C, respectively. Additionally, LSTs for open and super high‐rise, high‐rise, and mid‐rise LCZs were 37.4, 37.5, and 37.1°C, respectively. Therefore, this suggests lower‐rise and open LCZs are prone to increased urban heat intensities and higher‐rise and compact LCZs are an urban heat mitigation strategy. Open mid‐rise also offers heat reduction capabilities. Compact low‐rise and open mid‐rise spatial analysis also confirmed this trend with vegetation indices validating urban configuration as significantly influencing LSTs. Furthermore, due to LSTs constituting heat health risks, 11 municipalities comprised of predominantly compact low‐rise LCZs were identified as a priority for urban heat mitigation. Among these, Nakano, Nerima, and Suginami posed the greatest heat risks.