GENEVA — Extreme heat is becoming more frequent, more intense and longer-lasting as climate change raises global temperatures, the United Nations weather agency said, warning that current conditions in Europe illustrate how a warmer baseline is amplifying heat events.
The World Meteorological Organization (WMO) said on Tuesday that parts of Europe were experiencing their fifth heatwave of the summer, with drought, wildfires and record temperatures affecting several countries. John Kennedy, the agency’s head of climate information, said the pattern represented a significant change from heat events of previous decades.
“Extreme heat is becoming more frequent, more intense, it's lasting longer, and covering much wider areas than in the cooler climates of the past,” Kennedy told a briefing in Geneva.
The WMO said persistent high-pressure systems were helping drive the current European heat. Such systems can trap warm air, reduce cloud cover and prevent cooler air from moving into affected regions, allowing temperatures to remain elevated for days or weeks.
Kennedy said the current conditions were broadly comparable in atmospheric pattern to those seen during the exceptionally hot European summer of 1976, but occurred against a much warmer global background because of decades of climate change.
He also said El Niño was not contributing to Europe's heat this year because conditions in the tropical Pacific were neutral. Instead, exceptionally warm seas, including marine heatwaves in the Mediterranean and waters west of Europe, were providing additional background warmth. Parched soils were also intensifying temperatures because dry ground heats more rapidly after losing moisture.
The health implications are significant. The World Health Organization says increasingly frequent and intense heatwaves are among the climate-related hazards causing illness and deaths. In the WHO European Region, extreme heat was linked to more than 60,000 deaths in 2022, while the agency estimates annual heat-related deaths could reach 120,000 by 2050 without stronger adaptation.
Older people, infants, outdoor workers and people with chronic illnesses face particular risks during periods of high temperatures, WHO guidance says. Heat can worsen existing cardiovascular and respiratory conditions and increase the risk of other heat-related illnesses.
The WMO said the combination of global warming, persistent atmospheric patterns, unusually warm seas and dry soils was contributing to the exceptional heat observed across Europe this year. The agency continues to emphasize monitoring and early warning systems as governments prepare for rising heat risks.
