Non-Linear Response to Global Climate Change of Temperature-Related Mortality Risk in England and Wales

Background: Mortality risks associated with cold and warm weather are expected to change in the future due to climate change. Projections for future decades are generally represented following selected climate change scenarios. For the UK, the most recent projections are based on a set of scenarios published in 2000.Methods: Present-day temperature-mortality relationships for ten regions of England and Wales are modelled using distributed lag non-linear models. These are used in combination with climate projections from the updated UKCP18 dataset to quantify anticipated impacts of climate change on summer and winter attributable mortality for the present-day population without adaptation and mitigation measures. Results are presented relative to degrees of global warming instead of focusing on specific decades.Findings: We find a delayed emergence of increases in summer mean temperature-related mortality risk in England and Wales in response to climate change and a rapid escalation of the impact beyond 2·5°C global warming relative to pre-industrial levels. Conversely, winter mean attributable mortality is projected to decrease largely linearly with global warming. Seasonal extremes change at a faster rate than the seasonal mean and increases in summer extreme attributable risks are expected also at lower levels of warming.Interpretation: The impact of climate change on summer temperature-related mortality risk in England and Wales is currently mainly in the seasonal extreme, but significant increases in the seasonal mean are expected if global mean temperatures continue to warm beyond 2·5°C.Funding: UKRI Strategic Priorities Fund, Met Office, NERC Independent Research Fellowship, NIHR Academic Clinical FellowshipDeclaration of Interest: We declare no conflicts of interest.Ethical Approval: Ethical approval is not required for this study as it involves only the analysis of anonymised data obtained from the Office of National Statistics.