An early estimate indicates that more than 2,700 individuals may have died from heat-related causes during the United Kingdom's unusually hot weather in May and June. These periods of extreme heat were attributed to a "heat dome," a phenomenon where a large area of high pressure traps hot air over a region.
Researchers have linked the intensity of these heatwaves to human-induced climate change, which has contributed to a global temperature increase of approximately 1.4 degrees Celsius since pre-industrial times. This warming is believed to have added between 3 to 4 degrees Celsius to the peak temperatures recorded during May and June.
The heatwaves brought exceptionally high temperatures, with May seeing a new UK record of 35.1C at Kew Gardens, surpassing the previous high of 32.8C set in 1922 and matched in 1944. The hot conditions were exacerbated by tropical nights, offering little relief from the prolonged high temperatures.
Many homes in the UK are not constructed to withstand such extreme heat, leaving residents vulnerable. The human body experiences significant strain during intense heat, with the heart working harder to cool the body, a process made more challenging by dehydration.
Certain groups, including babies, older individuals, and those with pre-existing health conditions, are at higher risk of adverse health effects. Intense heat can trigger heart attacks, strokes, and other life-threatening emergencies. Even fit and healthy individuals can be affected, as heat is sometimes referred to as a 'silent killer' due to easily overlooked early symptoms. When the air is also humid, as was the case in June, the body's ability to cool itself through sweating is further impaired.