More than 2,700 people died from heat-related causes during May and June’s record hot spells in England and Wales, as climate change makes heatwaves more deadly, experts estimate.
Study Details and Findings
Researchers from Imperial College London, the Met Office, and the London School of Hygiene and Tropical Medicine (LSHTM) estimated that there were 2,700 excess deaths over the two heatwaves. They found that climate change significantly drove up the death toll, with more than two fifths (42%) of deaths resulting from the extra heat caused by human activity – mostly burning fossil fuels.
The study, which used peer-reviewed methods to deliver rapid estimates, examined the periods around the record-breaking heatwaves of May, when temperatures peaked at 35.1C, and June, which hit new highs for the month above 37C, accompanied by high humidity.
Attribution to Climate Change
The analysis used weather data, climate models, and heat-related deaths research to estimate the number of people who died in the heatwaves and compare it to how many lives would have been lost in a climate not warmed by human activities. About 550 people are estimated to have died due to heat-related causes in nine days of the May heatwave, and about 2,200 in the 11 days around the June heatwave. Around 59% of the deaths in May (327 people) and 38% in June (825 people) could be attributed to the extra heat caused by climate change.
The researchers warn that maximum daytime temperatures are now around 3C-4C hotter than they would be without climate change, raising health risks. High temperatures are associated with heat exhaustion, heat stroke, stress on the heart and kidneys, and worsening chronic conditions such as heart disease, lung conditions, and diabetes. They also worsen mental health, violence, and increase the risk of death from drowning.
Expert Comments
The Met Office’s Dr Mark McCarthy described the two record-breaking heatwaves as “exceptional.” He noted that heatwave thresholds are rarely met in May, but this year daytime temperatures were widely 15C above the average for the month in England and Wales, while night-time temperature records were also set. The June heatwave, which saw red warnings for extreme heat on consecutive days, was notable for its humidity as well as heat. “They were extreme heatwaves for the UK, and for all parts of western Europe, and they’re particularly exceptional for the timing and how early in the year they occurred,” he said. “This combination of extreme daytime heat, high humidity and hot nights all act to really contribute and increase the impact these heatwaves have on our infrastructure, on transport, agriculture and particularly on our health and well being.”
Dr Clair Barnes from Imperial College London said heatwaves are the “most dangerous kind of extreme weather,” with the World Health Organisation recommending that authorities in Europe plan for extreme heat in the same way they do for winter flu. She warned that while heatwaves prompt news images of people eating ice cream and sunbathing, “people need to be aware that we are now seeing dangerous climate-change fuelled heat that is claiming lives, disrupting schools and hospitals and shutting down transport and infrastructure.” She added, “It’s time we woke up to the fact that we now live in a country with dangerously hot summers. To protect people during future extremes, we must urgently adapt to the reality of the climate we now have, and double down on global efforts to reach net zero emissions to stop this from getting worse.”
Policy and Preparedness
The independent advisory Climate Change Committee has warned that the UK is unprepared for extreme heat, which could see 92% of homes overheating by mid-century, and has called for maximum temperature rules in workplaces and air conditioning in hospitals, care homes, and schools. The UK Health Security Agency (UKHSA)’s Professor Lea Berrang Ford said the modelled estimates provide an important indication of the potential health impacts of sustained hot weather. “While they are not a measure of observed mortality, they help illustrate the scale of risk associated with extreme heat and the growing threat climate change poses to our wellbeing.”
The UKHSA is due to publish its official interim analysis of heat-death impacts of the recent heatwaves based on mortality data in the coming weeks. Secretary of State for Energy Security and Net Zero, Ed Miliband, said: “The Government will not leave our children and grandchildren to face the costs of climate breakdown and nature loss. That’s why we are working with others to drive action bringing energy security and lower bills, backing British businesses and creating good jobs, and protecting our home and countryside for future generations.”
Zack Polanski, leader of the Green Party of England and Wales, said: “These deaths are on the hands of politicians who have failed to act over the years. All those who put profit over the safety of the public by refusing to take real action to prevent the climate crisis – and are now failing to protect us from its impact. The message is clear: without action to protect people from extreme heat, we will see thousands more deaths in the years to come. Something must change.”
London Ambulance Service had the busiest week in its history during the June heatwave with a record number of life-threatening emergencies. Alison Blakely, deputy chief paramedic, said: “As temperatures remain high, we would urge Londoners to take the heat seriously, stay hydrated and avoid strenuous activity such as running during the hottest parts of the day, as it puts extra strain on your heart and lungs.”
