As Europe endures its most severe and widespread heatwave on record, the continent is grappling with the devastating impact of rising temperatures, despite decades of warnings. On Wednesday, Pierre Masselot, an environmental epidemiologist, received a text from his daughter’s nursery, located less than 50 miles from the weather station that first broke the UK June temperature record this week. The message requested early collection of children due to dangerously high temperatures within the school buildings.
Similar scenes unfolded across Europe this week, as the oppressive heat, intensified by carbon pollution, highlighted repeated failures to adequately prepare for such events. France recorded its hottest day and night ever, while both the UK and Switzerland saw their June daily heat records shattered. This widespread heatwave underscores a critical lack of readiness across the continent.
For Masselot, an environmental epidemiologist at the London School of Hygiene & Tropical Medicine, who has become a leading figure in tracking the hidden death toll from heatwaves, the recent days evoke memories of the terrible summer heat that swept Europe in 2003. Though too young at the time to fear for his own health, he was old enough to comprehend the profound dangers it posed.
Back then, as a teenager in southern France, Masselot spent his summer camp days bouncing basketballs under the sun while brutal August heat transformed towns and cities across Europe into sweltering ovens. The relentless hot days strained bodies, and warm nights offered no respite. The majority of the 70,000 victims who succumbed to that summer’s extreme heat were older individuals, particularly women and those living alone.
Now, the extreme weather events that were once considered exceptions have become the norm, and today’s anomalies are set to become tomorrow’s regular occurrences. Masselot, now 37, warns that by the time his toddler reaches 14, the same age he was in 2003, global heating will have significantly surpassed the 1.5C (2.7F) target that world leaders pledged to maintain by the century’s end, pushing punishing extremes to unprecedented levels. “Climate scientists have been saying for a long time we’ll have a lot more 2003s,” Masselot stated. “Now it’s become painfully obvious this is the case.”
Despite persistent warnings and growing public awareness, heatwaves continue to cripple large parts of Europe. Several hospitals in England have declared critical incidents, struggling with failing cooling units and stalled critical IT systems. Schools, workplaces, and railway networks have been thrown into disarray, and wildfires have erupted. In France, where half of all homes lack adequate protection from high heat, more than 55 people have drowned while attempting to cool down, four young children have tragically died inside hot cars, and two nuclear reactors were forced to shut down due to insufficient cooling water.
Has Europe failed to learn from its past? The devastation of the 2003 summer did prompt the first serious efforts to combat heat, with governments implementing early warning systems linked to rapid response measures. These included limiting travel, closing schools, and canceling non-urgent hospital appointments when temperatures soared. Research indicates that such adaptations have proven successful, significantly reducing the sensitivity of mortality rates to temperature shifts. A study published in November found that if the 2003 heatwave were to strike today with the same intensity, the projected death toll would be 75% lower.
However, simultaneously, heatwaves are becoming hotter, longer, and more frequent, raising concerns about whether current adaptation efforts can keep pace with the escalating concentrations of planet-heating pollution in the atmosphere. This year, early warning systems were activated even before summer officially began, as a shocking May heatwave swept across north-west Europe, shattering the UK’s historical temperature record for May by a full 2C. Just two weeks later, Hans Kluge, the Europe chief of the World Health Organization (WHO), announced in Berlin an update to the WHO’s guidelines for heat health action plans, 18 years after their initial release. Only two weeks have passed since then, and Berlin is now facing 40C heat.
“The tragedy is twofold,” Kluge remarked, referring to the 200,000 lives the WHO estimates Europe has lost to heat in the past four years. “First, most of these deaths were entirely preventable; and second, this is just the tip of the iceberg, with millions more people being affected physically and mentally.”
Climate breakdown is causing Europe to heat faster than any other continent, a consequence of local weather patterns and its proximity to the rapidly melting Arctic. The current heatwave is no exception to these effects. A rapid attribution study released on Friday by World Weather Attribution (WWA) concluded that such an event would have been “virtually impossible” at this time of year just 50 years ago.
Of particular concern for human health are the sweltering overnight temperatures recorded this week, which scientists found to be approximately 100 times more likely than in 2003. Daytime peaks have also become about 10 times more probable. The study explicitly ruled out any influence from El Niño, the natural warming weather pattern that recently formed in the Pacific. El Niño is expected to reach its peak strength toward the end of the year and is likely to make 2027 the hottest year on record globally.
For scientists who have consistently warned about the worsening heatwaves due to rising carbon pollution, the failure to heed expert advice has become increasingly frustrating. “There’s a sad inevitability to all of this, with scientists like me trotting out the same quotes year after year,” said Friederike Otto, a climate scientist at Imperial College London and co-author of the WWA study, speaking before this week’s records were broken. “Yes it’s climate change, yes it’s us, no it’s not El Niño. Simply put, we remain on a one-way trip towards a more dangerous future, and it’s time we hit the brakes.”
So, what actions can be taken? Heat and health experts advocate for increased shading to block heat from homes, improved ventilation to cool them as temperatures rise, and more green spaces in cities to counteract the urban heat island effect. Hospitals require greater support, and citizens are urged to check on elderly or vulnerable neighbors. While some experts are cautious about the widespread adoption of air conditioning, citing risks of blackouts and exacerbating the urban heat island effect, they still recommend its use in care homes, hospitals, schools, and public transport. The latest WHO guidance suggests a nuanced approach, arguing that while it is “not a sustainable societal solution,” it “remains crucial” for individuals at increased risk from high temperatures.
The WHO’s stance on air conditioning has been vocally rejected by the US far right, which has transformed European aversion to mass air conditioning into a meme portraying the continent as poor and overregulated. In a post on X, boosted by Elon Musk, the platform’s owner, a US tech chief executive shared a chatbot-generated text stating, “Europeans should just install air-conditioning” and “the American approach to summer was correct all along.” This post garnered 19.5 million views.
Similar sentiments have been echoed by European far-right parties that have actively opposed efforts to expand clean energy or enhance home energy efficiency. Less than a year ago, Marine Le Pen, the leader of the French far right, called for a “grand plan” for air conditioning in the same week her party attempted to block new wind and solar projects. The latest surge of heat has reignited this debate in France, several months before presidential elections.
Yet, urgent calls to reduce emissions continue to be dismissed as centrist governments across Europe weaken climate policy and roll back green regulations in the name of competitiveness. UN Secretary General António Guterres, who warned that London was “cooking” at the start of the week, reiterated his longstanding pleas at London Climate Action Week on Tuesday to cease burning fossil fuels. The very next day, the organizers of a related panel on extreme heat governance canceled it because it was too hot. The day after, former US president Donald Trump advised the UK’s likely next prime minister, Andy Burnham, to “open up the North Sea” for oil and gas drilling, despite experts indicating it is a mature basin with at least 90% of accessible fossil fuels already utilized.
For Pierre Masselot, whose typical summer as a child involved staying indoors with all shutters closed—effectively living “in a cave from 10am to 6pm”—there has at least been some progress in public awareness of heat and how best to cope with it. “People have learned lessons and now we know the consequences it can have,” he said. “But sometimes it feels as soon as the summer has ended, we forget about it.”
