A new study suggests that, under realistic scenarios of high emissions and socioeconomic development, annual heat-related deaths in the U.K. could rise to about 50 times current rates by the 2070s, but that climate change mitigation and adaptation could significantly limit this rise. Rebecca Cole of the London School of Hygiene and Tropical Medicine, U.K., and colleagues present these findings in the open-access journal PLOS Climate.
Heatwaves are expected to become more frequent and more intense in coming decades in the U.K. Extreme heat is linked to higher risk of death, particularly for older people—a growing population—and those with pre-existing conditions. Predictions suggest that future heat-related deaths will rise, even under scenarios of strong reductions in greenhouse-gas emissions.
However, many prior predictions have not adequately accounted for population changes or adaptation strategies, such as increased use of air conditioning, passive cooling, urban greening, and the development of community networks to support vulnerable populations. To help address these challenges, Cole and colleagues estimated future U.K. heat-related deaths under more comprehensive scenarios of climate, population, and socioeconomic conditions, and with higher geographic resolution and coverage. They combined Representative Concentration Pathways, representing future climate scenarios under different levels of greenhouse gas emissions, with U.K.-specific Shared Socioeconomic Pathways, a set of plausible "storylines" for the country's socioeconomic future, including the potential for adaptation.
They found that, with high emissions and socioeconomic inequalities, an estimated 34,027 yearly heat-related deaths may occur in the 2070s—about 50 times a baseline of 634 yearly deaths calculated from past rates for 1981 through 2021. However, under scenarios of effective climate change mitigation and adaptation, the analysis estimates 4,592 annual heat-related deaths in the 2070s. The researchers note that this is still six times more than baseline, highlighting the need for increased adaption even in low-emissions scenarios.
Predicted heat-related deaths varied between regions in different scenarios, with rates generally lower in cooler Northern regions. The researchers also estimated that power outages may be responsible for up to 27 percent of heat-related deaths during a serious heatwave.
On the basis of these findings, the researchers note the importance of strategies that combine climate change mitigation and adaptation, with a focus on equity and resilience.
Lead author Dr Rebecca Cole adds: "Projected increases in heat-related deaths are not just a consequence of rising temperatures — they're also driven by how we build our cities, care for vulnerable populations, and address social inequality."
She also notes: "Even under a best-case scenario, where emissions are reduced and societies adapt, we project heat-related mortality to rise six-fold by 2070 compared to present day."