8 September 2023

At a glance:

In this report, we look at two increasingly important phenomena: an ageing population and rising temperatures in the UK, showing how they will dovetail dangerously in the next two decades.


  • Over the next twenty years, England in particular will experience a ‘deadly cocktail’ of an ageing population mixed with consistently rising temperatures to dangerous levels. The south east of the country will experience this heat most acutely, whilst the north and Scotland will be relatively less affected (but not immune).


  • In particular, the so-called “Home counties” are set to experience this crisis most acutely, as counties such as Hampshire, Kent and Surrey will see the greatest increases in the absolute number of over 65-year-olds. This will occur in a region of the UK set to receive some of the highest temperatures and extreme heat events.


    • Between Kent, Hampshire, Essex and Surrey, over 1.6 million over 65 year-olds are estimated to be living in a heat-risk environment for extended periods of the year by the year 2043, with rising average summer temperatures and increasing likelihoods of heat waves. This is a health risk that requires planning to avoid.


  • London boroughs will experience the sharpest percentage increases in over 65-year-olds in the context of rising general temperatures and extreme heat events.


  • The wider context here couldn’t be more stark: In England and Wales, the mortality risk during heat waves is predicted to increase by 42% with a 2°C rise in global mean temperatures, which could be reached under moderate to high emissions scenarios by mid-century.


  • Without adequate measures regarding building upgrades, urban infrastructure and health and safety policy, we can expect an increase in heat-related deaths and negative health effects amongst older populations.


Eleanor McIndoe

Will Stronge

Will Stronge, Director of Research at Autonomy, said:


“The Home Counties are at risk from a deadly cocktail of an ageing population combined with the highest projected temperatures. The Government’s Heatwave Plan is inadequate and leaves the country disastrously underprepared for future heat waves. Without action from the Government, we are very likely to see tragic consequences in the near future.”