Broiled by Heat Waves, Residents of the Concrete Jungle Suffer – Inside Climate News

Summer heat in New York City beats down on asphalt and tall buildings, which get hotter, scorching the locals, who can’t stop sweating. Exhaust from trucks and cars hangs in the air and the subway stations trap extreme amounts of heat.

Some residents face greater exposure to high temperatures than others. That depends on multiple factors—whether they have in-home air conditioners and can pay to run them, the abundance of trees and green space in their neighborhoods and the way the urban design that surrounds them traps and amplifies heat. 

Across the city, residents of color and low-income New Yorkers often suffer the most from extreme heat. According to city data, Black New Yorkers are twice as likely to die from heatstroke, with death rates twice that of white residents. An important factor in heat-related deaths is that Black and low-income residents are less likely to own or operate an air conditioner, due to the cost. 

The area around Newtown Creek—the small stream that separates Brooklyn and Queens—is over 8 degrees hotter than the average surface temperature across the city, according to City Council data on heat inequality—especially the radius that surrounds the creek’s tributaries, English Kills and East Branch. 

In a recent webinar to present the Newtown Creek Alliance’s findings on how extreme heat impacts this area, Shangtong “Sandy” Li, the community engagement coordinator for the local advocacy organization, stressed that the severe lack of tree canopy is a major contributor to the heat in the area.

“The canopy has a significant impact on cooling down an area,” Li said. 

This neighborhood is filled with industrial business zones. Its roads and parking lots are packed with trucks and heavy-duty equipment, which generate heat during operations. With little or no tree canopy in the area, these factors combine to expose workers and residents to more heat than other New Yorkers. 

A 2024 study by Climate Central revealed that the city’s built environment is making temperatures an average of 9.7 degrees Fahrenheit hotter for residents. For many residents, it can be deadly—3 percent of all deaths between May and September are heat related. 

The metropolis is full of microclimates across different neighborhoods—defined by the amount of green spaces, the size and geometry of the surrounding buildings and the number of vehicles driving through the neighborhood, among others. 

The urban landscape contributes to increasing temperatures because it absorbs heat from the sun and releases it slowly throughout the day and night, at a slower pace than nature. That is why nights are often hotter in built environments.

“We have all these processes that are the natural cooling mechanisms of the land—if we suddenly were to put a city next to that, it messes around with almost every aspect of that,” said Dr. Luis Ortiz, an assistant professor in the department of atmospheric, oceanic and earth sciences at George Mason University, and a member of the New York City Panel on Climate Change, an advisory body that helps inform policy on climate issues. 

“The geometry and the materials curtail or lower the ability of the land surface to cool as fast as it normally would in natural places,” he said.

A majority of city residents have air conditioners in their homes—around 90 percent according to city data from 2023. But not everyone can afford to run them all the time, increasing the chances of heat-stress and even heat-related mortality, especially for older residents and people with cardiovascular issues or other underlying conditions. 

It’s hard to fully understand how New Yorkers experience heat across the city, but research suggests that most heat-related deaths have their onset in the home. People may also be exposed to extreme heat outside and unable to cool down in their apartments. 

Amidst these challenges, some developers and architects are tackling the heat issue head on by using passive house standards when building and retrofitting homes. These standards, which prioritize airtightness and insulation, aim to maintain a comfortable temperature inside buildings throughout the year.

Other city initiatives aim to increase the number of trees along city streets in hotter neighborhoods. Mayor Adams’ 2023 PlaNYC: Getting Sustainability Done set out the goal of implementing a maximum indoor temperature for tenants by 2030, which would force landlords to provide cooling appliances when the area reaches a specific temperature. 

Heat in the City

Climate change is causing hotter summers. In New York City, this year’s heat came suddenly. In a late June heat wave, Central Park hit 99 degrees for the first time since 2012, and Gov. Kathy Hochul declared a state of emergency. 

The experience of that June heat wave for city residents varied depending on where they lived and worked in the city. New York is among cities where the temperature in low-income neighborhoods or communities of color can be 5 to 20 degrees hotter than other areas of the city.

These neighborhoods are often located farther from green spaces in the city and suffer more acutely from the urban heat island effect. Tall buildings in particular can create an “urban canyon,” said Ortiz, which traps heat in streets and prevents cooling breezes from meaningfully reducing the temperature on the ground. 

The general temperature in the city is projected to increase in the coming decades. According to the New York City Panel on Climate Change, the total number of hot days and nights in the city is predicted to increase between 15 and 52 days by the 2050s, with heat waves rising by a factor of two to four times higher than the current average. 

“Now, we need to think more about the concepts of thermal safety and how to make sure that we can design cities to be more comfortable,” said Dr. Yuliya Dzyuban, an assistant professor at the Pratt Institute Graduate Center for Planning and the Environment and a member of the New York City Panel on Climate Change.

Dzyuban leads so-called “heat walks” in city neighborhoods where she measures how different features of the urban landscape impact the thermal comfort of people walking through the neighborhood. On her walks, Dzyuban says she measures radiant temperature (how much radiation the body absorbs), air temperature, wind speed and relative humidity.

“During my walks, we went and measured surface temperature, and there was a dog park with an astroturf—when we measured that astroturf, it’s 130 degrees,” said Dzyuban. “Obviously the decision here was to prioritize maintenance rather than safety.”

To maintain the body temperature near 98.6 degrees, the body employs multiple levers to cool itself, including the evaporation of sweat. But when the surrounding air is very humid, the sweat does not evaporate as quickly, leading to less heat dissipation. This can be dangerous in instances of extreme heat, when this is the main means for the body to cool itself. 

Aging populations and people with chronic health conditions are particularly at risk during these moments of extreme heat, especially if they have no means to cool themselves in their homes. Between 2018 and 2022, an average of 525 deaths a year were attributed to heat stress, or due to an underlying illness that was exacerbated by heat, according to city data.

“In these neighborhoods, that lack of infrastructure to cool yourself when you get home is a predictor of the number of folks who pass away or have their onset of heat-related illness,” said Ortiz. 

Heat in the Home

According to the Mayor’s Office of Climate and Environmental Justice, the neighborhoods with the lowest rates of air conditioning were environmental justice neighborhoods—communities that have been historically overburdened with polluting infrastructure, like power plants. 

Even residents with air conditioners may struggle to afford running them, especially as utility bills rise. The percentage of households with air conditioning drops considerably in environmental justice neighborhoods. For example, in the West Bronx neighborhoods of East Tremont and Morrisania, the number of households with air conditioning is 76 percent. 

In response to concerns about homes being exposed to extreme temperatures, high utility bills and new laws that require greenhouse gas emissions reductions, some developers are examining the passive house building standard more closely.

This standard essentially calls for the building to be designed to be airtight—meaning that there is no circulation between rooms and limited air leakage from the building. Air circulates primarily through mechanical ventilation.

The building is also well-insulated, and its windows are usually designed to prevent warm or cool air from leaking out of the building. According to the Guardian, there are around 1,860 certified passive houses in New York City. 

Josh Shaffer, the capital planning and sustainability manager at RiseBoro, a community development nonprofit that builds affordable housing, has worked on passive house projects across the city. 

RiseBoro began developing and retrofitting its affordable housing portfolio to these standards to lower its operational costs because these homes usually have lower utility bills, said Shaffer.

According to Shaffer, the cost of building apartments to passive house standards is around 3 to 5 percent higher, which he believes is worth it to reduce long-term costs and residents’ utility bills. Most of that cost, he says, goes towards extra labor. 

“Contractors are not entirely familiar with some of the installation techniques around building air-sealing and methods of insulating,” said Shaffer. He added that there has been more familiarity with the standard in recent years. 

According to Shaffer, RiseBoro upgraded the outside of the buildings to improve insulation, while also switching their gas heating and stoves for electric appliances such as induction stoves and heat pumps. 

“What’s more surprising to me is how much we can improve buildings compared to the way that they used to be built—it’s really astounding,” said Shaffer. “Just by adding some more insulation, and potentially new windows, we can lower our energy cost.”

Heat in the Streets 

Heat-related illness and mortality are not just caused by exposure in the home, but also by the compounding effects of exposure to it outside. Streets with less shade and neighborhoods with less access to green spaces can create a greater risk for residents. 

Planting street trees can help provide shade to locals and cool streets. The city already has a plan to expand the city’s tree canopy to 30 percent. In September 2023, the U.S. Department of Agriculture awarded the city $15 million in federal funding to plant and maintain city trees. The Department of Parks and Recreation also currently prioritizes more heat-vulnerable neighborhoods when it plants trees. 

Adam Jaffe, a senior materials engineer at Arup, a consulting engineering firm, who works to make buildings more sustainable and lower operational costs, sees the way heat moves through the urban landscape that surrounds him. 

“My apartment, for example, looks out over an intersection that’s six lanes wide, and there’s a huge amount of black surface visible from my window—and it’s south facing, so the sun is arching over the sky and it’s hitting that surface,” said Jaffe. “That heat radiates out to the surroundings—the buildings facing onto that intersection.”

If the streets were lined with large trees that provide shade, Jaffe said, the surrounding buildings would get less hot, and the residents inside them might have to run their air conditioning less frequently. Research suggests that the average increase in cooling energy demand that can be traced back to urban overheating for all types of buildings is close to 12 percent. 

Ultimately, the problem of extreme heat in New York City requires multiple solutions, experts say, because it’s experienced so differently by each New Yorker. Ortiz emphasized that, because of this, people need to be better informed of the risks of heat exposure. 

“A lot of people don’t know what the symptoms of heat exhaustion or heat stroke look like,” said Ortiz. “They might just think they’re tired and keep walking or keep running or doing some other physical activity.”

In other ways, the city also offers residents respite from the heat they may not otherwise have. On hot days, the city operates cooling centers that provide a refuge for residents without air conditioning in their homes. People are also often able to walk into a local store if they are feeling too hot in the street—something that would be much more difficult in suburban or rural areas where commercial buildings may be more spread out. 

“This problem is so multifaceted that it should be addressed from different angles,” said Dzyuban. “It’s not just about streets and pedestrian comfort. It’s a healthcare issue. It’s an energy issue.”