Boris Johnson’s Government should devise and implement a ‘National Heat Risk Strategy’ following the revelation that several hundred people have again this summer been killed by high temperatures.

I have written to the Prime Minister to urge him to develop a coordinated cross-departmental strategy to manage the risks to health and the economy from the growing threat of heatwave conditions.

Deaths linked to recent heatwaves in the UK

The Office for National Statistics on 25 August published its provisional figures for deaths registered in England and Wales during the week ending 14 August 2020. It found that the weekly total had increased for the first time since early June, and that it was higher by 307 deaths, or 3.4 per cent, than the average for the previous five years.

Many parts of England and Wales experienced high daytime and night-time temperatures during the week ending 14 August, and the Heat-Health Watch Service operated by the Met Office and Public Health England was raised to Alert Level 3.

The Office for National Statistics concluded: “The increased number of deaths, and the rise above the five-year average, were likely due to the heatwave; the coronavirus (COVID-19) did not drive the increase, as deaths involving COVID-19 continued to decrease.”

An accurate estimate of the number of ‘excess deaths’ due to the high temperatures will not be available for many months, until the figures are studied by the Government’s experts on health statistics.

Previous analyses by Public Health England have revealed that in total more than 3,000 people died in England due to hot summer weather during 2016, 2017, 2018 and 2019. Many of these deaths could have been prevented if the UK had been better informed and prepared for heatwave conditions, which are growing in frequency and intensity due to climate change. In particular, the Government needs to develop a cross-departmental strategy for tackling the risks to health and the economy from hot weather.

England’s existing Heatwave Plan lacks impact

At the end of May, the Policy Innovation and Evaluation Research Unit at the London School of Hygiene and Tropical Medicine published its review of the Heatwave Plan for England. It concluded that “there is no definitive evidence” of the Plan’s impact since it was introduced after the heat-related deaths of more than 2,000 people in the UK and tens of thousands across Europe during August 2003. The review also pointed out that most recent deaths from hot weather occurred outside of the high alert periods of the Heat-Health Watch Service.

Although the Department of Health and Social Care had commissioned the research, and had received its findings from the London School of Hygiene and Tropical Medicine several months before the report’s publication, no changes were made to the Heat-Health Watch Service ahead of this summer. This meant that the Government missed the opportunity to implement changes that could have saved lives during the heatwave. And the Government has still not indicated whether it will act on the recommendations contained in the report.

It is important that the new National Institute for Health Protection reviews the strategy for managing the risks posed by hot weather, including the Heatwave Plan for England. It should also commission research into the impacts of hot weather on health and productivity. Recent reviews have revealed big gaps in knowledge about the precise mechanisms through which overheating cause illness and death, and there is little information about the circumstances in which people have died during hot weather in the UK. And while it is already known that productivity suffers if workplaces are too hot, there has been no research into the overall cost to the UK economy and of the benefits of investing in preventative measures.

An issue warranting cross-departmental attention

The growing threats from hot weather to well-being and prosperity in the UK need to be tackled by a much wider range of Government departments.


Many of those people who suffer most during hot weather are living in buildings that are prone to overheating. The Committee on Climate Change has pointed out that about 20 per cent of homes can overheat in the current climate, even in relatively cool summers, and has drawn attention to the particular challenges for care homes. This means we need a national investment programme to retrofit homes and workplaces to adapt them to hot weather. This could begin as part of the economic recovery package from COVID-19, alongside the programme to improve energy efficiency, and would create many new jobs across the country. However, it should be recognised that an increased reliance on air conditioning would have major implications for energy demand and electricity bills.

The Ministry of Housing, Communities and Local Government must also ensure that any new buildings are designed to cope with the increase in the frequency and intensity of hot weather. The National Planning Policy Framework was amended only in 2018 to explicitly mention the risk of overheating due to rising temperatures. It is essential that any changes to the planning system, about which the Government is currently consulting, do not undermine the requirement to prevent overheating in homes and workplaces.

Transport and other infrastructure

Buildings are not the only part of our infrastructure that is vulnerable to the impacts of increases in extreme hot temperatures. There was disruption to parts of the UK’s train network during heatwave conditions in summer 2019 due to buckled rails and the thermal expansion of overhead cables. Some roads were also closed as their surfaces started to soften and melt.

A report by the National Infrastructure Commission earlier this year warned of the need to ensure long-term resilience by taking into account the impacts of climate change.

Time for a national strategy

Given the wide range of impacts created by the increase in the frequency and intensity of hot weather, it is time for the Government to create a National Heat Risk Strategy.

As I outlined in my letter to the Prime Minister, the Strategy could address the following issues:

  • Retrofitting existing homes and workplaces to reduce the risk of overheating, and implementing building regulations to ensure new buildings do not overheat
  • Adapting other existing infrastructure, including transport, energy and communications, to make it more resilient to the growing effects of hot weather and ensure that all new infrastructure is similarly resilient to our warming climate
  • Engaging with businesses and communities to raise awareness of the risks of hot weather and the options for adapting to it
  • Increasing research on the effects of hot weather on health and productivity and the options for reducing the risks
  • Working with local policymakers to tackle the risks of heat, particularly in cities, which are more exposed because of the urban heat island effect.

The immediate risks of hot weather may have reduced for the next few months, with the end, today, of meteorological summer, but now is the time for the Government and the rest of the country to develop a strategy for next summer and beyond.

Bob Ward is policy and communications director at the Grantham Research Institute on Climate Change and the Environment and the ESRC Centre for Climate Change Economics and Policy at the London School of Economics and Political Science, and deputy chair of the London Climate Change Partnership.

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