What the Keep Bristol Cool mapping tool is, how it works, and how to give feedback on it.
Cities have a high concentration of:
- infrastructure systems, for example transport, energy, and water networks
This makes them more at risk during heatwaves.
In cities, people and the built environment, such as roads, homes, or offices, are exposed to higher temperatures than in rural locations.
High temperatures and heatwaves (urban heat) and their potential impact (urban heat risks), for example homes overheating or roads melting, affect communities differently within a city.
How vulnerable a person is to heat (their heat vulnerability) is made-up of many factors, including:
- their sensitivity to heat
- their ability to adapt to high temperatures
- their exposure to high temperatures indoors and outside
What the Keep Bristol Cool mapping tool is
The Keep Bristol Cool mapping tool is for policy makers and practitioners such as urban designers, landscape architects, or emergency planners to explore:
- how current heat vulnerability varies across different neighbourhoods
- how climate change may increase temperatures in the future
- gives insights into how urban heat risks vary across the city and within communities
- identifies the areas where high temperatures and heatwaves could have the biggest impact on people's health and wellbeing
This information will help us and other decision-makers in the city to build greater resilience to high temperatures and heatwaves.
The maps may be of interest to a wider audience, but the tool hasn't been designed for households to use when making decisions about their own homes.
How the Keep Bristol Cool mapping tool was built
We worked with experts from the Met Office and the Tyndall Centre for Climate Change Research, University of Manchester to map urban heat risk.
The work was funded by the UK Climate Resilience Programme that supports research to:
- quantify climate change risks
- build UK climate resilience
How the Keep Bristol Cool mapping tool works
The tool includes two sets of maps:
- a Heat Vulnerability Index (HVI)
- climate maps
The development of an HVI is a technique that maps factors that increase the negative impact of heat on people's health and wellbeing.
It uses the best available information at that time, including:
- population census data
- satellite imagery on land surface temperatures
- housing characteristics
This information is then brought together and processed to produce an overall index. A ranking system:
- enables different parts of the city to be compared to one another
- highlights areas where interventions may be useful to tackle urban heat risks
The Heat Vulnerability Index (HVI)
The Heat Vulnerability Index brings together information on:
- Bristol's population
- people's homes
- the local environment
This library of maps is made up of three different tiers of information:
- the top tier, the HVI, which identifies the most vulnerable locations in the city
- the middle tier, including the four underlying vulnerability layers (or key determinants of heat vulnerability), which have been used to build this index covering age, deprivation, indoor exposure, and outdoor exposure
- the bottom tier, including all 34 factors, which use open data to drive the index, for example population aged 65 or over and living alone, south-facing homes and green space
The climate maps
The Climate Maps give:
- information on possible temperature rises in the 2030s (2021 to 2039) and 2070s (2061 to 2079)
- baseline data for the 1990s (1981 to 1999) as a reference point to explore future change
This library of maps has been produced by the Met Office. They are based on high-resolution UK climate projections, called UKCP Local.
These projections have been generated using the Met Office's new climate model, which works at a scale similar to weather forecasting. They're based on a future where greenhouse gas emissions grow beyond current policy commitments, leading to greater levels of global warming sooner than expected.
We'd like to hear about how you're using this mapping tool.
Your feedback will help with the tool's ongoing development.
The Keep Bristol Cool Framework
We've used the information in the mapping tool to develop the Keep Bristol Cool Framework.
The framework sets out our plan for managing heat related risks to the city's population, public services and assets.
It covers 4 areas of focus needed to increase our resilience:
- Protecting people's health and wellbeing during heatwave events including maintenance of critical public services.
- Building urban heat resilience into new pieces of city, city infrastructure and new developments.
- Tackling overheating risk in people's homes.
- Using blue and green infrastructure for cooling streets and public spaces
There is also a separate Keep Bristol Cool Technical Appendix. This gives more detail on the methods used to develop the evidence base of Bristol's climate projections and the Heat Vulnerability Index.