Co-developed Environmental Solutions to Mitigate the Impact of Temperature Extremes on the Health of Vulnerable Populations

The physiological and cognitive impacts of extreme temperatures are known in general and mostly for healthy populations, but little is known about how impacts differ across the diversity of the UK population; in particular, those with multiple health conditions, including neurological, who are likely to be the most impacted, and for which interventions (e.g. green spaces) are poorly targeted or non-existent. Furthermore, we do not have tools to integrate available data to understand temperature-health risks nationally and at the necessary individual and household level, and therefore how to target interventions. More broadly, the evidence is lacking to guide policy on the coupled challenges of health inequalities, urban planning and climate change mitigation/adaptation, under uncertain futures of climate and demographic change.

Increases in heatwaves are a robust aspect of climate change, with associated increases in health-related deaths. Cold-related mortality has declined with overall warming, yet still far outweighs the increase in heat-related deaths, and the overall burden of cold-related illness and mortality will remain high with an ageing population. Most research on health outcomes has focused on excess mortality rates and limited to broad vulnerability groupings. Health outcomes are, however, much more nuanced, being related to both physical and mental health and exacerbated by underlying conditions including neurological and mental ill health, with exposure related to context specific temperature-humidity thresholds.

Therefore, there are significant gaps in our understanding of health risks (including long-term outcomes) for the most vulnerable, and how this relates to the interplay between variability of temperature hazards and outdoor/indoor exposure as driven by socio-economic gradients and mobility. We therefore envisage developing new knowledge and tools for precise risk assessment and targeted interventions, focused on disproportionately impacted groups. By doing so, we will transform our understanding of the drivers of inequalities in temperature related health outcomes and propose using this to inform policy on levelling up and pathways to climate targets.

We will realise our vision through an ambitious but feasible, highly multidisciplinary project that is necessary to address this complex problem. Our aim is to transform our understanding of the risk of temperature impacts on health outcomes for vulnerable populations of England and Wales with particular focus on health inequalities, currently and for future scenarios, and identify environmental solutions, directly addressing the overarching funding call objective. Our approach is multi-scale, with high granularity in both space and time: a) linking national scale risk assessment with detailed urban case studies to understand risks at the level of streets/buildings and vulnerable groups; and b) identifying how risks change with future changes in climate, demographics, mobility and health status. National scale assessment will reveal how extremes evolve across climatic gradients and land types, and we will explore the diversity of health outcomes and identify landscape configurations and socio-economic factors that are likely to lead to higher risks, and therefore potential mitigations that are resilient to future change. Community engagement will tease out the nuances of impacts and acceptability of environmental and community-based interventions. This will feed back to the national scale to inform on mitigation, via risk reduction tools for early warning, planning and policy. Our approach will provide a far more nuanced, informed and precise risk assessment than currently exists that will allow targeted interventions to be identified, providing risk reduction where most needed.