The annual number of heat-related deaths in England and Wales is set to rise up to fiftyfold over the next 50 years because of climate change
published in PLoS Climate, analysed the impacts of 15 different combined climate change and socio-economic scenarios over the next fifty years, comparing different levels of warming, different amounts of adaptation to protect against the effects of a warming climate, aging populations, regional climatic differences and the potential impact of power outages – a new approach for heat impact projections. Together, they are the most comprehensive projections for the impact of climate change on the population of England and Wales for the next century.
The researchers found that even under the most optimistic scenario, associated with 1.6 degrees of warming over preindustrial levels by the end of the century and with high levels of adaptation, the annual number of heat-related deaths will increase up to sixfold. Today’s baseline of 634 annual heat-related deaths will rise to 3,007 per year in the 2050s, 4,004 in the 2060s and up to 4,592 in the 2070s. The worst-case scenario, with 4.3 degrees of warming over the same period and minimal adaptation, would see up to a more than fifty-fold increase in heat-related deaths to 10,317 in the 2050s, 19,478 in the 2060s, and 34,027 in the 2070s.
Potential adaptations could include steps such as adopting passive cooling systems like cool and green roofs, better building ventilation and heat management, active cooling systems such as air conditioning, shady urban forests and greater community support for vulnerable populations.
For comparison, the record-setting hot summer of 2022 saw 2,985 excess heat deaths, indicating a potential “new normal” by as early as the 2050s. For the low emissions scenario this would mean an additional 21 to 32 significantly hotter than average days per year, and an additional 64 to 73 such hot days under the high emission scenario.
Senior author, Dr Clare Heaviside (UCL Bartlett School Environment, Energy & Resources), said: “Our collaborative research paints a sobering picture of the consequences of climate change, under a range of potential social and economic pathways. Over the next fifty years, the health impacts of a warming climate are going to be significant. We can mitigate their severity by reducing greenhouse gas emissions and with carefully planned adaptations, but we have to start now.”
Over the next fifty years, the population of England and Wales is expected to age significantly, with the greatest increase in population size for those aged 65 and over by the 2060s. Most previous research into the future impact of heat mortality didn’t factor in the impact of an ageing population, leading to an underestimation of its mortality.
This study broke England and Wales into nine regions to analyse the impact of climate change in different areas. Generally, heat mortality rates in the North are projected to increase less than rates in the warmer south across the different scenarios, but there is some variation.
In addition, the researchers modelled different levels of adaptation for a warming climate and the outcomes it would have on heat-related mortality. This includes factors such as health infrastructure, levels of urbanisation, energy infrastructure, inequality, fossil fuel emissions, adoption of air conditioning or other passive cooling technologies.
They found that the more adaptation society undertakes, the lower the heat-related mortality. But, while under lower levels of warming, adaptation plays a more significant role in reducing mortality, under the higher levels of warming, its effectiveness is reduced.
