Heat-related deaths 'will increase by 42% in UK’ if temperature rises 2C, scientists warn

Deaths directly related to temperature will soar by 42% in England and Wales if the world's climate warms by 2 degrees Celsius above pre-industrial levels, scientists have warned.

The rate of increase particularly speeds up at 2C of warming, with a much higher risk appearing beyond 2.5C.

British researchers said that 3C warming could lead to a 75% increase in mortality risk during heatwaves.

In 2015, almost 200 countries agreed to an ambitious goal to limit climate change, known as the Paris Agreement or Paris Accord.

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Signatories agreed to keeping temperature increase "well below 2C above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5C above pre-industrial levels".

At 2C, there would be an increase from present-day levels of around 117 deaths per day, averaged over the 10 hottest days of the year, to around 166 deaths per day.

At current global warming levels of around 1.21C we see a slight decrease in temperature-related mortality in winter and a minimal net effect in summer, meaning that overall, at this level of warming we see a slight decrease in temperature-related mortality rate.

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But this doesn't take side effects of extreme weather – such as storms – into account.

University College London's Dr Katty Huang, the study's lead author, said: "The increase in mortality risk under current warming levels is mainly notable during heatwaves, but with further warming, we would see risk rise on average summer days in addition to escalating risks during heatwaves.

"What this means is that we shouldn't expect past trends of impact per degree of warming to apply in the future.

"One degree of global warming beyond 2C would have a much more severe impact on health in England and Wales than one degree warming from pre-industrial levels, with implications for how the NHS can cope."

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The team analysed the 2018 UK Climate Projections (UKCP18) with data on present-day temperature and mortality in order to predict changes in temperature-related mortality relative to degrees of global warming.

Project lead Professor Andrew Charlton-Perez, of University of Reading, said: "As the Intergovernmental Panel on Climate Change (IPCC) impacts report recently showed, it is increasingly common to examine how different levels of mean global warming raise the risk of significant harm to people and society.

"Our study shows that because death rates will go up significantly if countries experience very high temperatures, limiting the average global rise in temperatures is likely to have substantial benefits for the overall health of the population."

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