News

Aug 04, 2023

On New York’s First 110

Good morning! It’s July 28, 2073, and it’s going to be a real scorcher, maybe a record. Yesterday was pretty bad in New York City — the thermometer reached 107, but you’ve seen it higher — and today

Good morning! It’s July 28, 2073, and it’s going to be a real scorcher, maybe a record. Yesterday was pretty bad in New York City — the thermometer reached 107, but you’ve seen it higher — and today is going to be even worse. It’s noisy in your apartment as you wake up because the city is repaving the street, just as it did last fall. As it happens, you have a midday flight to Montreal, where your client has relocated from Miami. There’s a knock at your door; it’s a wellness check, and a pair of EMTs are asking about your next-door neighbor, who is 89 and hasn’t been in touch with her family for a couple of days. The medical team borrows your spare key to check on her. She’s okay, but breathing a little hard and not moving around much, and they implore her to keep the air conditioner running.

When you step outside, the staff at the nicer buildings are hosing down the sidewalks, and they’re steaming. But at mid-block, where there’s no doorman, dogs are whimpering as their paws hit the concrete. They balk at crossing the street because the blacktop is even worse, literally hot enough to burn the pink pads on their feet. You had planned to take the new N-train extension to La Guardia, but it’s gone out of service because there’s a problem on the elevated trestle between the Broadway and 30th Avenue stops: The steel rails have expanded and buckled. Instead, you decide to take a taxi, and though the driver expresses some concern about his decreased battery range in this heat, you make it on time. Whereupon you discover that La Guardia is curtailing takeoffs till dusk — because at this temperature, the airplanes can’t take off safely when fully loaded.

Instead of sitting in the airport all afternoon, you decide to get on the short section of the N train that is running back to Astoria, and you find a café there so you can work. Through the window, you watch two high-school students set up a livestream. They’ve brought an aluminum frying pan out and laid it on the asphalt, and after a few minutes of preheating, they crack an egg into it, hoping for a sizzle. When they pick up the pan, the bottom brings some softened tar with it. The kids point an infrared thermometer at the blacktop and pull the trigger. It reads 152 degrees.

Most warnings about climate change focus, for good reason, on broad trends like average temperatures and sea-level rise. Those are the correct gauges to drive international action. But there’s a different, arguably more predictable kind of change headed our way besides storms and floods: acute heat. In the past, New York State might have gotten, on average, seven heat waves per decade. One projection says that, by the 2080s, the city could face as many as nine per year. The typical number of days per year above 100 degrees will (in one estimate) increase sevenfold by century’s end, from a couple at most to 28. The peak temperatures will be higher than we’ve ever experienced.

In New York City, the hottest day of the year has usually fallen just around 100 degrees Fahrenheit. Last year, it was 97; the year before that, 98. In 2011, it hit 104. The record in Central Park — in the shade — is 106 degrees, set on July 9, 1936. Today, at the end of what is likely the hottest month of the past 100 millennia, it will reach the mid-90s.

And in our future climate? I asked Luis Ortiz, who studies cities and climate at George Mason University, if he could make any projections for the end of this century — not for general trends but for the outliers, at the peak of a heat wave — and it turns out his data allow him to do that with some specificity. Under a medium-carbon-emissions scenario, he said, we’d reach that record of 106 fairly regularly: more than once a decade. Under a high-emissions scenario, it’ll be every two years. In that especially carbon-dioxide-rich future, we’ll get a 112-degree day once every seven years. The new record high would likely get into the teens. The kids with the egg and the skillet will have plenty of chances to make their movie.

Adapting to these higher temperatures may seem straightforward — after all, cities like Tehran and Cairo have lived with them for centuries. But the American Northeast is different, with extreme temperatures in both directions, and we’ve built accordingly. Developers in already hot climates barely have to think about infrastructure that works in the cold, about the destruction wrought by road salt on steel, about the pernicious freeze-thaw cycle that gradually destroys masonry. (The big cables holding up the Verrazzano-Narrows Bridge stretch as they warm up each summer, when the road hangs 12 feet lower than it does in winter. With the cycle of seasons, the bridge rises and falls, a breathing gray beast in the harbor fog.)

Consider, for example, the pavement in front of your home. Unless you live on one of the Belgian-block streets of Soho, it’s usually asphalt, and different cities use different cocktails of material. Michael Greenfield, a chemical-engineering professor at the University of Rhode Island who specializes in asphalt, explained to me that a lot of the formulas are laid out in a set of guidelines called Superpave (a term that sounds like the name of the least charismatic hero in the Marvel Cinematic Universe). Municipal authorities pick the mix that suits their summer and winter ranges. New York most often uses one called Performance Grade 64-22. The second number in that name refers to its low-temperature limit of minus 22 degrees Celsius, and the first indicates its upper limit: At 64 degrees Celsius, or 147 degrees Fahrenheit, the road turns from a firm, drivable surface to an unpleasantly viscous goo — which, you’ll notice, is mighty close to the 152-degree surface temperature mentioned above.

To be clear, our streets may not quite turn into streams of slow-running molasses. What’s likelier instead is a lot of rutting — that phenomenon you may have seen at the curb around a bus stop, where tires dig in and create grooves and waves. If the air temperature stays above 104 consistently, the streets can get rutted within a matter of days. Imagine the expense and mayhem caused by the need to repave thousands of miles of New York streets after a single weeklong heat wave. Not to mention the more immediate hot-tar problems: dogs burning their paws — and you may not even want to touch that pavement yourself. Just the other day in Phoenix, Arizona, the Washington Post reported, a toddler stepped out onto his family’s patio barefoot and was rushed to the hospital with blistered soles. Others have been scalded by water coming out of a hot garden hose. This morning at 10:32, when the air temperature was in the 80s and rising fast, I pointed an infrared thermometer at a Manhattan street, and it read 131.

In fact, that kind of managed misery turns out to be a recurring theme as I speak to engineers and public officials: New York City won’t flat-out disintegrate when we have 110-plus-degree summers. Instead, it will merely become more of an uphill and expensive battle to keep the physical city working — and, specifically, to protect the lives of the people in it.

Rit Aggarwala, who now runs the Department of Environmental Protection and is the city’s chief climate officer, and before that ran the Mayor’s Office of Long-Term Planning and Sustainability, emphasized that distinction to me: between issues of inconvenience and issues that are life-threatening. And, he says, “the first risk in a heat wave is the electric grid. There’s no question about that.” Without electricity, the city’s residents can’t run their air conditioners, and without air-conditioning, people die. Three summers ago, as the pandemic kept people home, the city gave away more than 50,000 air conditioners to people who needed them. They inarguably saved lives.

There are, of course, cities that are inescapably dependent on air-conditioning to a degree that New York is not. Phoenix is a place where every one of the past ten summers has had a day that hit at least 115 degrees. (A recent study estimated that a multiday power failure during peak heat in Phoenix could kill 13,000 people and send half the city to emergency care.) So I called David Hondula, a climate and health researcher who is also now in charge of that city’s Office of Heat Response and Mitigation, to ask him what he sees in our future. As it happens, he’s from New Jersey, so the summers of the Northeast are not outside his experience.

When I asked him what seemed like New York’s most pressing issue, he paused for a moment to think. “What really struck me,” he said, talking about his most recent visit, “was just how big the multifamily residential buildings are and how many of them seem to have air-conditioning units that didn’t appear to be top of the line.” He added, “They’re rusted — there has to be some high percentage that were in some state of disrepair or not operating super-efficiently. And the scale of the problem really intimidated me. Not that we don’t have large-scale problems here, but it was a whole different order of magnitude, what it would take to ensure that everybody could be cool and safe.”

It cost an estimated $100 million in 1990s renovation dollars to upgrade Stuyvesant Town to accept air-conditioning — and that didn’t include the actual AC, just the wiring and the windows. The thought of getting every bit of New York’s public housing properly cooled and remotely efficient is especially daunting, what with so many other expensive problems in that system. (Although a NYCHA pilot program to swap old radiators for new heat pumps, which also cool the air, is moving forward right now with real promise.)

Old masonry buildings like brownstones, though they can be stuffy and ill-ventilated, can also stay cool for long periods because their thick walls are not so permeable. Brand-new buildings, constructed in the past decade or so, have usually been at least planned with energy costs and carbon emissions in mind, with high-tech glazing and tight seals and better insulation and such. But the in-between ones, say a glass office tower from the 1960s or 1970s, date from a less energy-conscious era. Although it’s hard to make sweeping generalizations — because many buildings have been retrofitted and some were simply better engineered than others, and energy efficiency depends on a lot more than a building’s exterior skin — aging mid-century façades are, from the standpoint of retaining chilled air, basically made of cheesecloth. Look up the city’s energy rating for the Seagram Building, the mid-century icon built in 1958. Even with some recent improvements, according to the Urban Green Council, it scores 14 out of a possible 100. The owners reportedly got it up from 3.

Structural engineer Walter Hartnett, who specializes in façades at the engineering firm Thornton Tomasetti, said that plenty of midtown buildings of that era can be called “functionally outmoded,” adding that the maintenance can become expensive and burdensome as their systems and structures age. Even in newer towers, technology can do only so much with a glass pane: Hartnett’s colleague Jose Rodriguez, who runs the firm’s sustainability team in New York, said that every time he sees an all-glass building going up, especially in places like Florida, he has a Hmmm moment: “What’s the future going to be like?” When clients offer him inspiration photos as they begin a project, what they often show him is a glass-encased tower. “That’s what everybody thinks that they want, and it is definitely not going to be adaptive or resilient to what the future climate is,” said Rodriguez. Passive-cooling techniques, like careful attention to siting and solar shading that keep the cooling demand down, go a surprisingly long way, but glass is still going to let a lot of sunlight in.

Phoenix gets mentioned a lot in another context. A couple of times in living memory, and notably in 2017, the city’s Sky Harbor airport went on pause when the temperature hit 120. Certain models of aircraft, especially small commuter jets, couldn’t take off or land because hotter air is thinner and generates less lift, and therefore runways need to be longer and aircraft can’t carry as much weight. New York’s airports have not yet closed for heat, but La Guardia, like some other airports, already puts on aircraft weight restrictions that begin at 88 degrees and increase as it gets hotter. Need I remind anyone who has flown into or out of there that La Guardia’s runways are notably short?

Airports also face another problem, a human one. Much of the labor of loading, fueling, and maintaining planes takes place in full sun because you can’t very well create shade over the concrete apron or runways. Hotter workdays for the people doing that work will mean more breaks for hydration, shorter shifts, maybe a full-stop siesta in the peak of the afternoon. It will also likely mean that some people who could otherwise do the job will be less able to. Diabetics, for example, are more inclined toward dehydration and heatstroke, and for them, 110-degree days in the sun are an especially bad idea.

Even setting aside changes to mitigate the immense carbon output of jet air travel, the hot future may be one of fewer flights carrying less weight, especially at the peak of summer. That changes the world a little, and not just for you as a traveler. Fewer FedEx and UPS airplanes, presumably leading to higher costs and/or slower deliveries, would alter the economics of a whole lot of small businesses, for example. Or consider the extreme case of a transplantable heart, good for at most six hours.

At least you can take the train, right? Well, hold on. Railroad tracks that bake in direct sunlight can get 30 degrees hotter than the air and even warmer than that under heavy train traffic. Steel expands in the heat, and it is not uncommon for rails, during heat waves, to grow past their design limits and buckle, causing stoppages or derailments. “Sun kinks,” these bends are called. It has happened in the New York subway system, in 2006 out in the Rockaways. That will not be a never-again incident. It occurs often enough now in the U.S. that the Department of Transportation has issued a report. Metro-North, being electrified from overhead on some of its routes, faces a different problem. The catenary — the set of wires running along the route above the train that supplies power — stretches when it gets hot, and it sags. The trains have to slow down to keep running.

Heat also stresses old electrical systems — insulation breaks down; lubricants in relays dry out — and a not-insignificant amount of the subway’s electrical wiring dates to the 1920s and 1930s, some of it cloth-covered, inflammable, and pervious to water. Jamie Torres-Springer, president of construction and development at the MTA, reminded me that today’s electronic signaling and communications gear is sometimes differently vulnerable because it has to be kept cool to work well. Our newer subway cars were ordered with the hot future in mind; if you read deep into the specs, they are required to operate properly up to 158 degrees, which is a generous margin. The older trains that we’re still running had semiconductors that were specified up to 125, a considerably lower margin. Torres-Springer told me that the agency often now gives builders a set of performance conditions, like a peak temperature, and effectively says, Tim Gunn–ishly, “Make it work.”

That’s the crux of it. All these things are manageable if we pay attention and spend money. The MTA is about to conclude a huge assessment of all its assets, for example, and will prioritize the ones that need help most, particularly as (one hopes) that congestion-pricing money starts flowing in. Historically, though, Americans have disliked spending money on fixing infrastructure; we build new things pretty well, but we are often careless and cheap about maintenance thereafter. We repair things only when our hand is forced, by which time they are in rough shape, near if not beyond the end of their service lives, and that costs more than taking care of them and making gradual incremental improvements. We’d rather let a bridge rust away and then replace it instead of giving it a coat of paint every couple of years.

In fact, that is one dim little bright spot in this story: Things wear out anyway. Our streets get repaved something like once a generation, and that will in turn give us a window in which to upgrade the asphalt to a higher-temperature mix. Subway cars last a half-century or so and then are replaced. Quite a few of the oldest glass-walled skyscrapers have already been reskinned, sometimes to freshen their appearance but also to save money on energy. We will have dealt with some of this, mostly cyclically, by the time the 110-degree days come around. Our broken down–ness now is, paradoxically, something that will help us catch up.

We can learn in large ways and small. Hondula told me about a program that Phoenix has been testing to give city streets a pale-gray coating, and those streets are now ten or so degrees cooler. Hondula told me that it does reflect heat back upward — keeping the street cooler but making pedestrians themselves hotter — but it’s obviously good for preserving the pavement and definitely easier on doggy paws. Other proposals for similar products and processes are out there. Your own New York City building may already have replaced its black roof with a silvery-white one.

Once (or let’s say if) some of those changes come to pass, New York City will not end up a barren, parched sand flat. We are not a temporary city fed by disappearing aquifers or an overcommitted river, like Scottsdale or Las Vegas. (Allen Ginsberg: “When gas and water dry up / will wild mustangs / inhabit the Hilton Arcade?”) Under even the most dire climate-change projections, the ones in which we end up building a cofferdam at the rim of New York Harbor, our climate is still subtropical. Our water system is relatively robust. When our summers are like Austin’s, the city will endure, albeit dramatically changed, as a place where millions of people live.

There’s one other upside. Those temperatures that are pretty tough for people to tolerate? They kill rats.