A collaborative study involving experts from Imperial College London, the Met Office, and the London School of Hygiene and Tropical Medicine has estimated that thousands of people may have died during the unprecedented heatwaves that impacted the UK across May and June. Researchers based these projections on established data regarding the dangers of extreme heat, noting that the majority of these fatalities likely occurred during June, which stands as England’s warmest June on record.
During that month, temperatures reached 37.7C in Lingwood, Norfolk, significantly surpassing the previous record of 35.6C established in 1957. A rare red heat alert was issued for parts of England and Wales, warning even healthy individuals of significant risks to life. Earlier in the season, May temperatures reached a new UK high of 35.1C at Kew Gardens on May 26, far exceeding the previous record of 32.8C that had stood since 1922 and was equalled in 1944.
Experts attribute both events to a "heat dome," a stalled area of high pressure that trapped hot air over the region. Researchers emphasize that this phenomenon was exacerbated by human-induced climate change, which has warmed the planet by approximately 1.4C since pre-industrial times, likely adding between 3C and 4C to the maximum temperatures recorded. The situation was further intensified by hot tropical nights, which provided little relief for the public.
The impact of the heat was particularly severe because many UK homes are not designed to cope with such conditions. Intense heat places immense physical strain on the body, forcing the heart to pump harder and faster to cool the system down. This risk is compounded by dehydration and humidity, which makes it harder for the body to cool itself through sweating. While babies, the elderly, and those with existing health conditions are most vulnerable, researchers warn that extreme heat is a "silent killer" that can affect anyone, as early symptoms are frequently overlooked and can lead to fatal emergencies like heart attacks and strokes.
Dr. Clair Barnes, an expert in extreme weather and climate change at Imperial College London, noted that these estimates serve as a warning. She stated that if the findings highlight the dangers and encourage changes in behavior during future heatwaves, she would be pleased, adding that the goal is to prevent such high death tolls. The UK Health Security Agency (UKHSA) noted that heat health alerts and actions taken across the NHS and care system likely helped mitigate the impact. However, scientists warn that as greenhouse gas emissions continue, heatwaves are expected to become more frequent, longer-lasting, and more intense.
