I am, in the summer, the human equivalent of a slightly overcooked noodle.
This is especially true in a coastal city like Washington, D.C., where I live. The heat and humidity seep into my bones and I attain a semi-liquid state in which, despite my enthusiasm for hiking and kayaking and swimming and all those other good summer activities, I find myself craving exactly one thing every time I go outside: Air conditioning.
Air conditioners, for better or worse, have become our default solution for extreme heat. When concrete and steel construction replaced regional architecture around the world, air conditioners — where people could afford them — awkwardly, imperfectly filled the spaces left behind by missing local design and materials that would have otherwise helped cope with the weather. And as the world gets hotter, ACs are growing more and more popular: In India, where I mostly grew up without an AC, sales of ACs have skyrocketed over the past decade from three million units in 2013 to an expected 9.7 million this year.
But there is, of course, a catch. As vernacular architecture disappears, so too does vernacular knowledge; many of us, bowing to our cooling-machine gods, have forgotten how to deal with the heat.
Air conditioning has an odd side effect: It makes us dependent. In a 2021 study from Georgia Tech’s Urban Climate Lab, which modeled indoor heat across Atlanta, Phoenix, and Detroit during heat waves, researchers found that people without air conditioning would fare better during a blackout because they’d be more likely to take other measures to help deal with the heat. These are simple moves, like drinking more water and using curtains to keep their rooms dark and cool, whereas people with air conditioning might put too much faith in their appliances — and be entirely unprepared for those appliances to stop working.
“I think a combined blackout and heat wave is the most deadly climate risk we’re confronting right now,” said Brian Stone Jr., director of the Urban Climate Lab and a Professor in the School of City and Regional Planning at Georgia Tech. “A blackout situation really kind of inverts the traditional risk pyramid. If you don’t have air conditioning in your house, you probably have greater heat resilience. Those of us who have air conditioning whenever we want it are going to be more susceptible.”
Heat waves put extreme stress on power grids, and blackouts are increasingly common as summers get hotter. If more people buy more air conditioners without any work being done to shore up the grid (and, believe me, the grid badly needs shoring up), that extra stress could lead to quicker, more common grid failures. It’s unfortunately easy to imagine just how dangerous a grid failure can be: A major blackout during a heat wave would be the inverse of the Texas blackout during the winter of 2021, when hundreds of Texans died of hypothermia in their own homes.
For someone in a house without an air conditioner, a blackout during a heat wave probably wouldn’t affect the temperature inside much; someone who does have one, however, will inevitably find their house heating up beyond a point they were prepared for. As Rebecca Leber pointed out in Vox, early-season heat waves are dangerous because our bodies aren’t prepared for the heat. The sudden loss of air conditioning for someone used to it is dangerous for the same reason.
Our built environment, like a natural ecosystem, is the sum total of many pieces fitting together, and not all of them fit perfectly. Air conditioners are the perfect example: They aren’t universally good at cooling our buildings down, especially if those buildings weren’t built with air conditioning in mind — they often lack proper insulation, for example, which means cooled air will escape a room quickly. That means air conditioners will have to work harder to cool the air, which both further heats up the air outside and places more stress on the grid. When the built ecosystem fails, its human inhabitants inevitably suffer.
Last week, I wrote about a study out of Portland, Oregon, that measured how hot the units in three public-housing developments got during the summer of 2022. To the surprise of the researchers conducting that study, the units with air conditioners were not much cooler than those that didn’t have them. There were a few reasons for this: first, running an air conditioner is expensive, and residents with air conditioners would often turn the temperature up to save on electricity costs. Second, the buildings weren’t designed for air conditioning, so the apartments couldn’t retain cooled air very well.
Third, and most importantly, the residents who didn’t have air conditioners were both more cognizant of heat dangers and more likely to take other steps to cool their spaces down; they retained, in other words, a sort of vernacular knowledge of how to deal with the heat.
“The residents who don’t have air conditioners go to great lengths to keep their homes cool,” said Dana Hellman, a program manager at CAPA Strategies, the climate consultancy that ran the Portland study for the city. “For example, they made DIY insulation for their windows or kept all their lights off or their curtains closed all day long. It’s burdensome, but it might be leveling the field a little bit.”
Which isn’t to say that air conditioners should be abandoned wholesale. If indoor temperatures rise too much, everyone is at risk of heat stroke. Many cities, including Portland, operate cooling centers for residents to go to during extreme heat events. But none of those cities mandate that those centers have some sort of backup power option, and even if they did there aren’t nearly enough centers to serve every resident.
As with climate change more broadly, there are obvious equity issues here: The people who are most likely to use cooling centers are the people who are most likely vulnerable in other ways, as well. More well-off residents can afford to pay for an air conditioner, its associated costs, and possibly also a backup generator to help them ride out a heat wave in the comfort of their own homes; many cooling centers are understaffed and under-resourced, which raises safety concerns for residents who then have to choose whether to stay home or potentially put themselves at risk for the sake of finding relief from the heat.
So what should we do as the world continues to heat up?
We can start with the long, hard task of adapting the grid to keep us safe during heat waves, a fix that Stone points out is decades overdue. “Back in the 90s, the idea was that we’d be successful in reducing global emissions and wouldn’t need to adapt [to global warming],” Stone said. “If we had acknowledged to ourselves that it was going to be a 20 to 50 year project just to start adapting, we might have been more attuned to the fact that the electrical grid is a life support system for us when it is too hot outside to be healthy. But that’s been a slow realization.”
In Portland, the housing authority has a program to provide public housing residents with free air conditioners. But there are other forms of adaptation, too: Stone and his colleagues found that cool roofs, which reflect more sunlight than traditional roofs, can lower ambient temperatures by 1 to 1.5 degrees Celsius. Urban tree cover, which throws potentially life-saving shade onto houses and roads alike, can also go a long way towards cooling things down.
Most important, however, is actually going to be changing the way we interact with heat. Education — getting people to take heat waves as seriously as, say, a hurricane or wildfire — is just as important as modifying our built environment. Perhaps we'll all, as Morgan Meaker wrote in Wired last year, take a leaf out of the Spanish playbook and adopt the siesta (an idea that I personally endorse), or learn to live in the dark caves of our curtain-darkened apartments in the peak of summer.
I may even start turning up my AC to let my body acclimatize to its natural state of noodle. Whatever the solution, heat must re-enter our vernacular: not just as something we mechanically force out of our homes, but as something we figure out how to live with.
Interstate Renewable Energy Council