Severe heatwaves that struck England and Wales during May and June are estimated to have contributed to the deaths of around 2,700 people, according to researchers who studied the impact of the unusually high temperatures.
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The findings were released by experts from Imperial College London, the UK Met Office, and the London School of Hygiene & Tropical Medicine, who analysed mortality trends during two major heatwave periods this year.
According to the researchers, approximately 550 deaths were linked to the heatwave between May 21 and May 29, while an estimated 2,200 deaths occurred during the more intense heatwave from June 18 to June 28. The June heatwave was particularly severe, with temperatures reaching 37.7 degrees Celsius, making it one of the hottest periods recorded in the region in nearly 50 years.
Professor Friederike Otto said the majority of heat-related deaths occurred during the June heatwave, when prolonged high temperatures placed significant pressure on public health. She warned that even healthy individuals should not underestimate the dangers of extreme heat, stressing that climate change is expected to make such events more frequent and intense in the future.
Researchers said both heatwaves were associated with a heat dome, a weather phenomenon that traps hot air over an area for an extended period, causing temperatures to remain exceptionally high.
Medical experts noted that prolonged exposure to extreme heat can increase the risk of heart attacks, strokes, dehydration and other life-threatening health conditions, particularly among older adults and people with underlying illnesses. However, they emphasized that healthy people are also vulnerable during prolonged periods of excessive heat.
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The study highlights growing concerns about the public health impacts of climate change and underscores the importance of heat preparedness measures, including early warning systems, public awareness campaigns and support for vulnerable communities during periods of extreme weather.