Beads of sweat are collecting around the small of your back. Your brain feels like it’s suspended in chicken broth. Your eyelids are droopy, and your skin is hot. If only the windows in your office could be opened. If only one of your co-workers had a fan.

As anybody who’s been through this harrowing experience knows, living in most parts of America during the summer these days means being dependent on A/C. With temperatures regularly climbing past 90, we expect to be made thermally comfortable everywhere we go, including in the cars or subways we take to get there.

Since the technology was invented in 1902, and the first window unit was brought to market in 1939, air conditioners have become ubiquitous in the United States. Today, almost 90 percent of American households have one—as do the vast majority of restaurants, stores, museums, and office buildings. During weeks like the one we’ve just had, these places are sanctuaries: To walk into one after being outside is to be reminded how sweet life can be.


But all that magic chilling comes at a cost—something most people are aware of on a personal level, because their electricity bills are so high during the summer, but not so much on a global scale, which is really where the problem lies. In China and India, air conditioning sales have reportedly been growing by 20 percent per year; around the world, air conditioning energy demand is projected to increase vastly over the next decades. According to Stan Cox, author of the 2010 book “Losing Our Cool,” air conditioning in the United States already has a global-warming impact equivalent to every US household driving an extra 10,000 miles per year.

Scotty Reifsnyder for The Boston Globe

But although there are a handful of anti-A/C crusaders out there, the idea that we need to be using less of it hasn’t become a touchstone of environmental enlightenment, like recycling or hybrid cars. This may well be an indication of how deeply it has shaped our world: While we can imagine giving up plastic bags and Styrofoam, living without climate control seems unfathomable, especially during a heat wave.


Until recently, however, civilization was humming along just fine without this costly convenience—and going back might not be as impossible as we think. The human body is quite well suited to deal with heat if we let it, and if we back away just a little bit from our assumptions about what it means to be comfortable, it’s easy to picture an alternate reality in which, instead of flipping on the freon at the slightest provocation, we learn to cope with the air we have. The human body is surprisingly adaptable, and by weaving together techniques from the past, ideas from hot-weather countries, and new findings from building design experts about what people actually find comfortable, we can see a surprising portrait emerge of what life might look like if we, as a society, decided we could no longer afford our addiction.

A lot would have to change. We’d wake up earlier, and nap in the middle of the day to make up for it. We’d ride bikes and scooters everywhere, and swimming would replace running as the preferred form of exercise. Maybe we’d see the return of porch culture—of screened-in card games and flowing iced tea. And maybe we’d start taking pride in tricking out our finished basements. After a while we’d get used to it, just like we got used to the artificial indoor chill we take for granted now. And who knows—eventually we might even come to like it.


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When experts look at A/C use in America, they immediately see a spot of illogic: We use vast amounts of energy just to let businesspeople do something they’d probably rather not do anyway. “We are probably overcooling our office buildings by 4 to 6 [degrees] F just so that office workers, particularly the males, can wear their business suits,” wrote Richard de Dear, who is head of architectural design science at the University of Sydney and a researcher on thermal comfort. “The current clothing behaviour is costing us a fortune in energy and greenhouse emissions!”

Scotty Reifsnyder for The Boston Globe

In Japan every summer, in an environmental initiative called “Cool Biz” that started in 2005, government officials encourage building managers to let temperatures climb to 82 degrees and advise employees to loosen their sartorial standards. In 2011, the government even put on a fashion show, with models catwalking in untucked polos, capri pants, and Kariyushis, a Japanese take on the Hawaiian shirt.

Here in America, it probably wouldn’t require such a hard sell. Many female workers already dress for summer weather, and would likely be delighted not to have to huddle in sweaters against the A/C. Among men, polos are already considered appropriate on casual Fridays, and it’s not hard to imagine that most would happily embrace a breezier style for the rest of the week. Instead of long pants, they could don formal shorts—a concept that has long been embraced in Bermuda, where executives can be seen attending meetings with exposed knees.

Even a mid-sized building could save considerable amounts every year by operating at shorts temperature. But if modifying what we put on our bodies could help us give up extreme climate control, rethinking buildings themselves—and how we ventilate them—would go even further. Already, some of us live in homes that can be effectively cooled by opening windows in the basement and on the top floor every morning, thus taking advantage of the so-called stack effect to pull cool air up through the house and allow hot air to vent into the street. People can also try “evaporative cooling,” a modest, low-tech form of air conditioning, by hanging wet towels in the window or setting them in front of a basic electric fan.


On a more structural level, we can also build houses to offer extra protection against the heat, using principles ignored by most modern architects. According to William Cooper, a professor at Louisiana State University and the coauthor of a two-volume history of the American South, people with the means to do so used to construct homes that stood several feet above the ground, in order to get air circulating under the floor: “They had long halls through the middle of the house, so if you opened a door at each end, you got a breeze coming through, and you’d have windows on the sides so you’d get cross-ventilation.”

Southerners had other tricks, too. In a paper published in 1984 in the Journal of Southern History, University of South Florida, St. Petersburg historian Ray Arsenault lamented the disappearance of architectural traditions that together added up to “an ingenious conspiracy of passive cooling.” Some of those traditions, Arsenault said, could make a comeback in a post-A/C future. “We’d be paying a lot more attention to where our shade trees are,” he said, noting that Southerners would always try to plant theirs on the east and west sides of their homes, to protect from the rays of the rising and setting sun. Those who could afford to built their homes with wide eaves, awnings, and high ceilings, so that hot air could rise and float far above their heads.


In a world less reliant on air conditioning, a house’s attic and basement would play far different roles than they do today—the former as a crucial component of a ventilation system, the latter as a place to spend leisure time. Underground space, kept at a constant temperature by the surrounding earth, stays far cooler than any structure that sits above it, which means basements could become central meeting places for friends and family, the way living rooms are today.

Not that we’d be spending all that much time in our homes. “People pour from inside to outside without air conditioning, no matter how hot it is,” said James Goodman, author of a book about the 1977 blackout in New York, which sent thousands of people out into the streets on a sweltering July night. Kids would put away their Playstations and start playing outside again. Outdoor barbecues would become less of a special occasion and more of a routine. Indoor gyms would become unappealing; swimming and crack-of-dawn aerobics would become the rule.

Scotty Reifsnyder for The Boston Globe

Even sitting around would be different. With A/C, many people stay indoors as much as possible on hot days, protected from the elements by their hermetically sealed igloos. But without climate control, those elements become a person’s best hope for comfort, which is why porches used to be such an important part of life in the South: Not only could people sleep on them at night, they could also use them as places to hang out during the late afternoons and evenings. If Americans were to stop relying so much on air conditioning, chances are we’d see the emergence of a new kind of porch tradition, even if it did involve more people sitting out with laptops and smartphones than visiting with their friends and neighbors.

Ultimately, what we do might end up being less important than what time we do it. Being intelligent about our daily schedules is one of the best weapons humans have against the heat. Under the current regime, most people go to work in the morning and expect to stay productive until the evening—even during the excruciatingly hot middle part of the day. But in some parts of the world, cultures have simply engineered their days around the climate: think of the Southern European and Latin American custom of leaving work for a midday siesta, and then coming back until evening before eating a late supper. In a 2004 essay published in ID Magazine, design writer Barbara Flanagan described living in Barcelona, with hardly any A/C, and explained how this created not just a unique schedule but a livelier civic culture, with people congregating in the proverbial public square every evening and staying out as late as they could. “This grand civic agreement—that everyone shall shop, dine, and party during the same windows of coolness—allows even the smallest neighborhood to enjoy a few hours of urban intensity,” Flanagan wrote.

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There are some parts of life, it must be said, for which air conditioning is not just a luxury but a necessity. The Internet depends on servers that require climate control in order to not go up in flames. Modern skyscrapers depend on it, as well. If we gave up air conditioning, New England would largely be fine, at least for now, but entire swaths of the country would become uninhabitable: Summers in the Sun Belt cities and in parts of the South would be so harsh that millions of people would simply move away. We also would be unwilling to take away A/C from those most sensitive to extreme heat—namely, the sick, the very young, and the elderly.

Scotty Reifsnyder for The Boston Globe

That doesn’t mean that trying to reduce our society’s addiction to A/C is a fool’s errand. The fact is, our bodies are built to adjust to heat—it’s just that we haven’t had to lately, because we’ve become so accustomed to refrigerating ourselves when the weather gets hot. A study in which researchers surveyed 21,000 people, spread out across 160 buildings on four continents, found that “people in warmer climates were more comfortable in warmer indoor temperatures than their counterparts in cooler climate zones,” according to Richard de Dear, one of the coauthors.

The findings indicate that people actually prefer being in places where the temperature fluctuates, as long as they have some control over it. “If you have the ability to open or close a window, turn a fan on or off, change the blinds, modify your clothing—it just becomes a natural part of your day-to-day living, and you don’t build these expectations that conditions should be the same all day and all year round, which I would call ‘thermal monotony,’” said Gail Brager, an architecture professor at UC Berkeley who also worked on the study. “We not only accept—we actually prefer—a wider range of conditions that float with the natural rhythms of the outdoor climate.”

No doubt this is hard to believe, as you sit there in your air-conditioned home, happily soaking up the artificial breeze emanating from the murmuring machine in your window. But is there not something fearful about refrigerating ourselves with such vigilance? We’re not cartons of milk, after all; we will not spoil, even if we do sweat a little. In fact, by taking full advantage of the technology inside our own bodies—technology that makes it possible for us to adapt to a whole spectrum of temperatures—we might discover we’ve been missing out on a way of life that actually feels quite natural.

Leon Neyfakh is the staff writer for Ideas. E-mail lneyfakh@globe.com.

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