The phenomenon melting long-standing temperature records is due to a heat dome parked over Europe, with clear skies and strong sunshine intensifying the effect for large swaths of the continent. Temperature records have been broken in France, the United Kingdom and Spain, with red alerts issued in Germany, Belgium, Italy, Switzerland and the Netherlands.
A study published Friday by World Weather Attribution found that the heat wave is the most severe ever recorded in the region and has been driven by climate change, with rising temperatures outstripping the rate of global warming.
The quick-turn analysis, undertaken by researchers from across Europe, focused on the three hottest days and nights in Europe this week, and an additional analysis of 19 capitals of affected countries.
Theodore Keeping, an extreme-weather and wildfire researcher at Imperial College London who worked on the study, said the “striking” results show how quickly climate change is driving an increase in the likelihood of extreme weather events.
“We’d expect to see heat like this more frequently in July and August,” he said. “If we’re breaking temperature records in some parts of Europe and it’s not even July, let alone August, that obviously means that this is a really big heat-wave event, and if it had occurred later in the year, it would have been even hotter.”
Previous periods of extreme temperatures have led to tens of thousands of deaths, researchers said, with 60,000 people dying in the summer of 2022 across Europe, and 47,000 heat-related deaths the following year.
The WWA study compared temperatures seen this week to those measured in 1976 and 2003, when other major heat waves were recorded. In 1976, it would have been “virtually impossible” to see the kinds of temperatures in June experienced this week, researchers said, and highly unlikely at any other time of year.
In 2003, during the first heat wave of the century, such temperatures would have been 10 times less likely than today, while nighttime temperatures would have been more than a hundred times less likely, the researchers added.
The United Kingdom recorded new maximum temperature for June two days in a row, on Wednesday and Thursday, when it reached 36.7 degrees Celsius (98.06 degrees Fahrenheit) in the southwest, according to the Met Office. Spain’s Aemet reported its hottest June days on Tuesday and Wednesday. France saw its hottest afternoon ever measured on Wednesday, with an average of 38.5 Celsius (101.3 Fahrenheit) across the country, followed by its hottest night on record, according to the national meteorological association, Météo-France.The WPA study also shows June is warming faster than any other month across large parts of Western Europe, with daytime and nighttime temperatures rising at around twice the rate of global warming.
A similar heat wave in June 1976 would have been around 3.5 degrees Celsius (6 degrees Fahrenheit) cooler during the day and 2.4 degrees (4 degrees) cooler at night. Even in 2003, the daytime temperatures would have been around 2.4 degrees Celsius (3 degrees Fahrenheit) cooler and 1.3 degrees (2 degrees) cooler at night, the study found.
The “tropical nights” — where the temperature does not drop below 20 Celsius (68 Fahrenheit) — have limited people’s ability to recover from the hot weather, Armel Castellan, extreme-heat services technical adviser at the WHO-WMO Joint Office for Climate & Health, said in a Thursday statement.“This is why, when assessing the health impact of a heat wave, minimum temperatures can be more telling than the peak afternoon high,” he said. A day with higher overnight minimum temperatures “carries a much higher health risk.”
Governments across Europe have taken steps to limit the impact of the heat wave, closing schools, issuing emergency plans and canceling train services. In Paris, Police Chief Patrice Faure announced a ban on drinking alcohol in public places this weekend because of the risk of heatstroke, according to French media reports. Dozens of deaths have been reported from heatstroke and drownings, including at least 45 people in France.
The World Weather Attribution researchers said in the study that the greatest impacts of heat waves are concentrated in cities where houses, transport systems and energy infrastructure were not designed for such extreme heat.
High levels of humidity have also exacerbated the effects, because higher dew points make it harder for sweat to evaporate. Researchers used temperature and humidity data to approximate wet-bulb globe temperature measurements — a composite metric that combines humidity, radiant heat and air movement to provide a more “physiologically relevant” assessment of how heat affects people.
One of the researchers, Carolina Pereira Marghidan of the Red Cross Red Crescent Climate Center, said in a statement that many people across Europe “still live, work, and study in places that are not designed for the temperatures we are now experiencing.”
“Despite widespread heat warning systems and heat action plans across the continent, the heat continues to impact health, transport, energy systems and daily life. We need greater investment in heat-resilient homes, cities and infrastructure to keep people safe.”Ben Noll in Auckland, New Zealand, contributed to this report.
