The number of hot days in the UK each year is likely to almost double because of climate change, according to a new study by the Met Office.
The number of days exceeding 25C could rise from about 10 to 18 a year if the climate warms 2C above pre-industrial temperatures.
The Paris Agreement aims to keep warming to less than 1.5C, and current climate commitments from governments are expected to lead to a rise of 2.4C globally if they are met.
Fewer snow days and less ice on the roads are also likely in future. The Met Office said the amount of disruption in the UK due to extreme cold weather is likely to fall, with the number of days reaching freezing temperatures to drop from 50 to 34 at 2C of warming.
The thought of such temperatures might seem welcome as Britain experiences a decidedly rainy summer, but the Met Office warned that extreme heat brings risks to human health.
The likelihood of hitting 40C temperatures could rise to one in 15 years by the end of the century, according to an earlier Met Office study.
"It’s very easy to think it would be beneficial to have more hot days and milder winters. But the consequences are that more people will die, so this is extremely worrying," said Hannah Cloke, a climate scientist at the University of Reading, who was not involved in the study.
"We also can’t separate these warmer days from having more heavy rainfall and drought."
There are an estimated 8,000 deaths a year due to high temperatures in the UK, and more than 44,000 due to cold weather, according to a study rom Monash University.
Extreme heat exacerbates respiratory and cardiovascular issues, putting older and more vulnerable people at particular risk. Those with diagnosable mental disorders such as dementia or psychosis are also found to be much more at risk during heatwaves.
The same study found that, in the short term, there were likely to be fewer deaths globally from temperature effects as climate change made the most extreme cold snaps less likely. But it suggested that in the long run, warmer temperatures would lead to rising fatalities.
Heat-related deaths increased by 0.21 per cent between 2000 to 2019, a period when global temperatures rose by 0.26C per decade.
British homes are ill-equipped to cope with overheating even in current temperatures, the Government’s climate change committee has warned, with thousands likely to require retrofitting for ventilation.
The Met Office also warned that the number of days with enough rainfall to potentially cause flooding is likely to rise from seven to nine under a 2C temperature rise.
The shifting of temperatures across Europe – with the north predicted to get warmer and wetter, and the south to experience drought – is expected to bring about a change in the fortunes of the continent’s farmers.
The value of agricultural land is expected to increase in the UK, particularly in Scotland, as conditions become more favourable for growing crops, such as tomatoes, normally associated with a Mediterranean climate, according to researchers at the University of Antwerp in Belgium.
But the loss of farmland in southern Europe and Africa to drought and extreme heat could lead to shortages and threaten the UK’s food security, MPs warned in 2019.