Europeans have been enduring extreme heat waves without air conditioning. Americans are confused.

The World Cup kicked off nearly three weeks ago and, so far, it's been a transatlantic lovefest. Germans have gone gaga over Buc-ee's. Brits have smuggled ranch dressing home in their suitcases. Scots have scooted down Boston's cop slide while playing the bagpipe. And in return, more and more Americans seem to be conceding that soccer is actually, you know, a real sport.

But there's one thing the Old World and New World still can't agree on: air-conditioning. Americans have AC everywhere. Europeans do not. And both sides are acting like the other is dangerously deluded. 

The debate over indoor climate control has become especially heated now that millions of European World Cup fans have been keeping cool in American bars, restaurants, hotels and even stadiums at precisely the same time the continent has been suffering its worst-ever heat wave — and as the U.S. is set to experience a similar scorcher of its own this week. 

Shock and schadenfreude 

Over the last 10 days, temperatures have approached 112 degrees Fahrenheit in some pockets of Europe. Schools have closed. Train tracks have warped. And the World Health Organization has recorded more than 1,300 excess deaths there since June 21 — a tragic toll that includes children who died in locked cars and young people who drowned while seeking relief in local waterways.

On social media, Americans have reacted with shock, superiority and schadenfreude.

"If Europe is too cold to need AC, why do they have such a huge number of heat deaths?" the popular economics writer Noah Smith wrote last week. "Just install the goddamn f***ing AC and save your grandma's life, Euro friends!"

Even Tesla and SpaceX CEO Elon Musk felt compelled to weigh in, sharing what he praised as a "banger" post by his Stripe counterpart Patrick Collison: 

Meanwhile, the response from some Europeans has been to… blame America. 

"Dear American journalists and social media 'influencers': for days, some of you have been criticising and making fun of Paris because the city does not have A/C in every room...OMG, this is so rich!" Audrey Pulvar, deputy mayor of Paris for international relations, wrote over the weekend. "As the second-largest emitter of greenhouse gas emissions in the world, you bear a significant amount of responsibility for global warming and the consequences we, in France, are experiencing. Your cities, which are 90 per cent air conditioned, are not unrelated to this."

Culture clash over climate change

Pulvar's math is correct: Around 90% of American households have AC, versus just 20% across Europe (and a mere 4% in the U.K., according to a new University of Reading study).

Part of the reason for this massive gap is meteorological: In the past, northern Europe in particular rarely got hot enough to justify widespread AC. Another part of it is architectural: Centuries-old buildings are harder to retrofit with central cooling, and window units or rooftop HVAC units often violate strict regulations meant to preserve their historical look. And part of it is economic: electricity is way more expensive in Europe than in the U.S. 

But as Pulvar's post indicates, Europe's biggest complaint about AC now involves climate change. Opponents there note that air-conditioning accounts for 4% of global emissions each year, and they cite studies showing that the systematic, citywide use of indoor cooling during a heat wave can boost outdoor air temperatures "by up to 2.4°C." As a result, they contend that widespread AC use is a self-indulgent, antisocial luxury — and that people should temporarily sacrifice their own comfort for the common good.

American AC proponents — and, increasingly, some right-wing European populists seeking to harness heat wave politics — have argued that global AC use represents a tiny source of emissions compared to China's ballooning carbon footprint; that both the technology itself and the electricity that powers it are rapidly getting greener; and that, in the end, cooling European buildings during a heat wave would increase economic output and productivity — while also saving a lot of lives.

Ultimately, the transatlantic divide over AC reflects deep cultural differences, according to the Atlantic's Thomas Chatterton Williams, who splits his time between the U.S. and France.

"Americans have grown accustomed to treating temperature in particular and physical distress more broadly as challenges to be fixed rather than states to be endured. This is in keeping with our flattering self-conception as optimizers and pragmatists," Williams wrote on Sunday. 

But Europeans, he continued, "pride themselves on small but telling displays of thrift: conserving water while washing dishes; wearing extra layers rather than turning up the heat in winter; scraping plates clean at dinner. These are people who still carry within them memories of war, occupation, and stretches of extreme privation.The idea that America is the land of abundance while Europe runs on a scarcity mindset is a cliché for a reason." 

A coming shift? 

Now that Europe is warming twice as fast as the global average — and now that its heat waves are becoming more frequent and extreme — there are signs that resistance to "air con" might be waning. 

The U.K.'s National Housing Federation has estimated 90% of homes there —  homes historically designed to retain warmth in colder weather — will overheat by 2050. Air-conditioning sales have been "booming" lately, according to the BBC, with one company saying "inquiries for its home units [are] up by 300%." Chinese air conditioner sales have been surging across Europe as well. 

In the Guardian on Monday, U.K. writer Phineas Harper made the "progressive case" for AC, arguing that it "should not be a question of whether or not to use it outright, but where, how and alongside which other infrastructure upgrades will make the most positive impact." 

Finally, when visiting World Cup fans return home this summer, memories of America's artificial chill will travel with them.

"One thing the World Cup has taught me is that Americans might be onto something with this air conditioning stuff," Victor Vacheron, a 35-year-old comedian and software designer, told the Washington Post. 

"Absolute bliss," added YouTuber Jono Yates, 39. "The best thing in the world."