Developing an Urban Heat Resilience Plan for Bristol - priorities for tackling heat vulnerability to protect health and reduce harm

In the UK climate change is resulting in increases in temperature and the occurrence of extreme heat events, causing multiple risks for society, particularly those most vulnerable. Impacts include increases in heat-related deaths and decreased workplace productivity. Approaches to reducing these impacts include adaptation of buildings, reducing the Urban Heat Island through green space and better medical planning for heatwaves. To successfully build resilience, a detailed understanding of the causes and how the risks vary spatially is required; this can be achieved by the development of a Heat Vulnerability Index (HVI) which illustrates where and why, people and infrastructure are most at risk. Complexities in the development process of HVI's, and scarcity in some of the data required, has resulted in HVI's being limited. Generally, this work is performed by academic or industry experts.

This project is a collaboration between Bristol City Council (BCC) and Charlotte Brown from the Tyndall Centre; its primary aim is to develop a HVI and a subsequent Heat Resilience Plan (HRP) for Bristol. This will build on previous work by the researcher to simplify and streamline the process of developing a HVI to make it more accessible to non-experts such as local authorities. Finally, the embedded researcher will utilise the day to day contact and specific engagement events, to fully understand and define local authorities' roles and needs in the space of urban heat risk. The HVI will incorporate multiple factors known to contribute to heat risk: Urban Heat Island, building characteristics and social factors. These will be described, quantified and mapped using GIS software, producing visual aids to enable variation in risks to be understood.

1. To understand the effect of the Urban Heat Island, outdoor temperature data, land use and land cover characteristics will be collated. Due to a lack of spatially dense air temperature data for Bristol, these characteristics will be used with pre-defined statistical models to produce spatially dense synthetic air temperature data.

2. Buildings characteristics known to increase or decrease their likelihood of overheating such as age, orientation, construction type will be used to analyse risks posed by the built environment.

3. Indicators which alter human vulnerability to heat risk, such as age, pre-existing diseases, measures of poverty, will be used.

All factors will be averaged over various spatial scales and mapped. Spatial patterns and hot spots of risk can then be identified and analysed. Normalisation and ranking methods will be used to quantify the combined risk. This will be summarised in a heat vulnerability report highlighting the most vulnerable locations and the most prominent causes of heat risk in these areas.

Heat stress is a complex issue which cuts across a number of policy areas impacting sectors such as transport, energy, and planning. Therefore, responsibility within the council falls across a range of departments. Focus groups will be used to engage with and work with these teams during the research process. This will ensure the research covers all relevant aspects and is designed to meet the widest possible needs. After the HVI is complete focus groups will again be used to co-develop a HRP. This approach to co-developing research utilises both academic knowledge as well as expertise on policy and practical implementation within the council. The HRP will guide Bristol to building heat resilience in the long and short term, by identifying several adaptation plans, with pathways to implementation. The HVI and HRP will then be widely disseminated beyond BCC to maximise their use. Both outputs are scheduled to feed into relevant policy and strategy plans due for renewal. Finally, the results will be disseminated to an academic audience highlighting results as well as reflecting on the process, and the role of local authorities.