In late May, Jannik Sinner, the world’s top-ranked men’s-tennis player, was closing out a dominant second-round performance against Juan Manuel Cerúndolo, ranked fifty-sixth, at Roland Garros. The French Open, as English speakers tend to call it, takes place during a traditionally splendid time of the year, when Parisians delight in the temperate air.
Sinner, a lanky twenty-four-year-old Italian with red hair, sharp elbows, and ground strokes like shotgun blasts, had won thirty consecutive matches and was the overwhelming favorite. After cruising through two sets, he was one game from victory, with a win probability above ninety-nine per cent. Then, as Cerúndolo prepared to serve, Sinner grimaced, took a few gingerly steps, and stretched his apparently cramping legs. They had played for less than two hours, but this May felt like August. Paris lay beneath a heat dome, and the red-clay courts were baking in direct sunlight.
Ordinarily, Sinner attacks with explosive energy, crouching on his long legs before springing upward, his feet leaving the ground after each shot. Now he slapped awkwardly at the ball, his shoes seemingly stuck in the clay. He lost the next two games badly, then complained of possible dehydration and called for a medic. After a nearly ten-minute time-out, play resumed. Sinner hobbled on, grimacing, dizzy, stiff, and weak. He lost the set, then the next two, and so the match. “The heat got to him,” an announcer proclaimed, deeming the famously fit Novak Djokovic a new favorite to win the tournament. The next day, Djokovic vomited on the court during the fifth set and lost.
Jakub Menšík, a twenty-year-old Czech who reached the semifinals, fared even worse. After winning a four-hour-and-forty-one-minute match, he collapsed onto the clay, where he writhed with cramps for more than four minutes as medics brought ice. “It’s insane to play in this weather,” he said, after being taken to the locker room in a wheelchair.
For generations, the French Open has embodied the ideal gateway to the European summer. In 2026, the spectacle of world-class athletes breaking down in sweltering conditions became the latest sign that the Continent’s rapid warming is bringing that ideal to an end.
Although climate scientists warned in the nineteen-eighties that extreme heat posed a growing danger, policymakers in Europe didn’t come to grips with it until August, 2003, when a heat wave killed more than seventy thousand people. What those officials still failed to plan for was that Europe would warm at a rate more than twice the global average. A number of regional factors explain why. One is the Continent’s connection to the rapidly warming Arctic. Retreating snow exposes darker ground that absorbs more sunlight; as soils dry, they’re less able to help with cooling the air. Meanwhile, strong winds carry hot air north from Africa, while declining aerosol pollution admits more sunlight, in a process called “brightening.” Together, these effects have set the stage for the fierce summers, destructive wildfires, and suffocating heat domes that now threaten Europe’s health, culture, and economy.
Historically, heat has evaded crisis-level attention. Unlike camera-ready disasters—hurricanes, earthquakes, tornadoes, floods, fires—blistering temperatures rarely produce images dramatic enough to go viral. The typical victims are old, poor, and socially isolated residents of disadvantaged areas, making heat waves invisible killers of people largely invisible in public life.
In the past five years, however, Europe’s heat has become too lethal to ignore: an estimated seventy thousand heat-related deaths in 2022, forty-eight thousand in 2023, and sixty-three thousand in 2024. This June—Western Europe’s hottest on record—at least ten thousand excess deaths were recorded as Paris topped a hundred and five degrees Fahrenheit, Bordeaux hit 108.5, and Gascony reached 111.7. The Eiffel Tower and the Louvre closed early, the museum explaining that its building is “not sufficiently adapted to climate change.” A nuclear plant in southwestern France shut down a reactor because the river water used to cool it was too warm. Dozens of young people, including a twenty-one-year-old professional footballer, drowned while seeking relief in open water; three French children died in broiling cars. Some Parisians took refuge in air-conditioned hotels.
The fact that rooms were available during Europe’s prime vacation season suggests trouble for its nearly three-trillion-dollar tourism industry, a hefty share of the Continent’s G.D.P. More visitors are giving up on summer holidays in cities that feel like saunas and booking “coolcations” in Iceland, Norway, or Denmark. In one survey, more than half of travellers said that they had avoided particular destinations because of extreme weather or natural disasters. A 2023 European Commission study forecast “a clear north-south pattern in tourism demand changes” that “becomes more pronounced for higher warming scenarios,” signalling growing economic consequences for Madrid, Lisbon, Athens, and Milan.
“Travelling to European cities is about cultural experience,” Daniel Scott, a scholar of tourism at the University of Waterloo, in Ontario, told me. “Whether it’s Paris, Barcelona, or Rome, you amble around, sightseeing, street shopping, taking a riverboat tour, going to a museum, a restaurant, a café. Most of that time, you’re outside.” Climate change increasingly turns pleasure trips into exercises in escaping pain. “When I’m in Europe, I always notice how many people crowd under trees and shaded areas,” Scott said. “But at some attractions, like the Acropolis, there’s no way to avoid the blazing sun. On especially hot days, they’ve got the Red Cross giving out water, medics pre-positioned because they know many people are going to be in trouble when they come down.”
Paris, like the Acropolis, was not built for this weather, and has been slow to adapt. The French are famously wary of air-conditioning, considering it an affront to cultural norms, a threat to architectural beauty, and an accelerant of warming. An Ipsos survey published in June found that seventy-eight per cent of the French regard air-conditioning as “not respectful of the environment.” Only some twenty-five per cent of French homes have air-conditioning, compared with around sixty per cent in Italy and eighty-nine per cent in the United States.
The problem is that this summer is only a preview of the treacherous weather that lies ahead. Météo-France projects that France will experience five times as many extreme-heat days by 2050 and ten times as many by 2100. Survivors of the coming climate-changed decades may remember 2026 as mild.
Most European governments, unlike the current American Administration, recognize climate change as a profound threat. More mechanical cooling, through conventional air-conditioning or less carbon-intensive technologies like heat pumps and geothermal systems, seems inevitable, even in France. So do electrification and greater investment in renewable energy. Yet nation-states have moved slowly. It’s in cities, where the danger is most urgent, that architects, planners, and officials are racing to lower the temperature of the landscape, inventively redesigning it around three ancient forms of cooling: water, soil, and shade.
This July, I arrived in Milan just as Europe’s third heat wave of the summer entered its fiercest stretch, following what meteorologists called an “Omega block”: a high-pressure system had trapped hot air from the African deserts over the Continent, blocking cooler currents. The heat posed more than an urban public-health threat. Across Western Europe, it was creating the conditions for a vast wildfire emergency that in late July displaced more than three hundred thousand people in France and Spain and killed a dozen in Almería province.
I had come to meet Stefano Boeri, a Milanese architect and urban planner known for designing buildings, and occasionally whole metropolitan areas, around trees. First, I wanted to see his signature project, Bosco Verticale: two apartment towers, twenty-six and nineteen stories high, whose deep balconies hold enough trees, shrubs, and flowering plants to fill twelve acres of woods, not to mention some twenty species of birds, all of which Boeri considers tenants. I had seen Bosco Verticale in countless photographs and videos, but encountering it at street level was exhilarating and surreal. Squinting up from the muggy sidewalk, I saw the buildings towering like giant redwoods, their leafy, wind-rippled façades startlingly alive.
