Every year, Chicagoans relish the onset of “Summertime Chi,” when the frigid winter gives way to summer heat and outdoor spaces come alive with concerts and neighborhood festivals. But the rising temperatures that make Chicago more vibrant can also be deadly.
As climate change increases the frequency and intensity of heat waves, city dwellers face extra risk thanks to the urban heat island effect, in which man-made changes to the environment drive up temperatures in metropolitan areas.
Within cities, too, heat disparities can place disadvantaged populations in additional danger. For people living in consistently hotter areas, there’s typically fewer shade trees offering shelter from the sun, little extra money to pay for air conditioning, obstacles in getting medical care for health conditions that pose deadly risks in extreme heat.
To intervene where aid is most needed, local officials and organizations in dozens of cities have participated in a National Oceanic and Atmospheric Administration program launched in 2017 to map heat disparities and raise public awareness. But Chicago has never applied, according to NOAA.
So the Tribune set out to identify which communities may be more at risk and assess whether the city’s government is doing all it can to help them survive before the next heat wave strikes.
Compiling a decade’s worth of temperature data gathered by satellites and analyzing it by U.S. census block group brought the city’s historically hottest areas into view. Though the land surface temperatures recorded by the satellites are more extreme than air temperatures, these readings represent the best available option to track differences. The resulting map, produced in collaboration with researchers at Boston University’s Center for Climate and Health, is the most detailed picture to date of disparities in heat exposure across the city.
Census estimates indicate that more than 300,000 people live in areas where average summer surface temperatures are hotter than 90% of the rest of Chicago, or an estimated 5 to 10 degrees warmer than the city average. Latino residents disproportionately shoulder the burden of Chicago’s heat disparities, the data show, while white residents disproportionately benefit from living in areas with the coolest average temperatures.
The local aphorism that it’s “cooler by the lake” can’t fully explain these disparities. Certain inland neighborhoods, such as Ukrainian Village and Logan Square, have tended to be cooler than some communities closer to Lake Michigan, including East Pilsen and Chinatown. Urban planning decisions, such as industrial zoning, play a large role in creating and sustaining cities’ hotter areas, climate experts note.
A Tribune analysis found that cooler areas with more white residents have far more parks and bus shelters — amenities that provide relief from heat — than areas with the hottest average surface temperatures and more members of minority groups. And substantial portions of Chicago’s most vulnerable communities can’t readily access any public cooling resource, Boston University researchers found.
With intense weather events growing in frequency, many cities across the U.S. are ramping up interventions to protect vulnerable residents. Los Angeles, for example, identified thousands of locations for new bus shelters to ensure 75% of commuters have access to shade. Boston provided hundreds of air conditioners to high-risk residents who live in local heat islands. New York City mandated new, more comprehensive studies on local heat deaths.
In Chicago, former Mayor Lori Lightfoot created a climate action plan in which heat-mitigating interventions were largely limited to planting trees and encouraging the installation of green roofs. It also committed to creating a heat vulnerability index that officials said would be used to inform planning decisions by this year. Then Lightfoot lost her bid for reelection.
Chicago’s new mayor, Brandon Johnson, promised voters to resurrect the Department of Environment, take action on air pollution within his first 100 days, make progress on the climate plan, create a Green New Deal jobs program as part of a Clean and Healthy Buildings ordinance and include climate change curricula in schools. Johnson has also raised the prospect of new utility bill aid. But proposals to alleviate the mounting burden of extreme heat are otherwise absent from his plan for environmental justice.
There’s no shortage of strategies a city can adopt to make urban heat more bearable, according to Sara Meerow, an Arizona State University researcher who has co-authored two American Planning Association reports on strategies to make cities more resilient to extreme heat. Meerow said a city’s interventions should align with its overall goals — such as equity — and the priorities of people who live in hotter areas.
“It’s going to be really critical to actually work with those communities and figure out: ‘We know there’s an issue here. What do you actually want to address it?’” Meerow said.
Nestor Flores is the director of behavioral health initiatives at Pilsen Wellness Center. A green roof tops the group’s flagship building, located among some of Chicago’s hottest average surface temperatures. From there, he said, the downtown looks like “a castle” compared with living conditions in the surrounding community.
Flores appreciates the benefits a green roof brings to the organization, but he is dubious that the city’s focus on green roofs as a climate solution can address the core environmental needs he sees every day. “Just as there was a time of uneven access to running water, inequities now come in the form of access to clean air and cooling,” he said.
What’s needed most from city government, Flores said, is accountability to ensure effective solutions.
“This is real life, people in vulnerable situations; our safety is at stake and health,” he said.
Heat is the deadliest weather phenomenon, killing more people in an average year than hurricanes, tornadoes, floods and cold, according to the National Weather Service. Heat kills some outright via heat stress. For others, heat exacerbates common chronic conditions, including asthma, heart disease and diabetes.
In 1995, an estimated 740 Chicagoans infamously died as a result of a four-day heat wave — more than 400 in the initial tally and hundreds more from conditions aggravated by heat, as determined by a Chicago Public Health Department epidemiologist. People without air conditioning made up the majority of deaths deemed avoidable by federal health authorities.
The havoc wreaked by more recent heat disasters, such as last year’s record-breaking temperatures in the Southwest and the Pacific Northwest, serves as a reminder that the threat is increasing. In Chicago, scientists say mounting days of extreme heat will mark life across the city for at least the next 30 years.
“We will see more heat waves like the ‘95 Chicago heat wave,” said Elena Grossman, director of the new Climate and Health Institute at the University of Illinois at Chicago. “That will become a constant reality.”
[ How we reported on heat disparities in Chicago ]
To help identify areas facing potentially greater risk, the Tribune and the Boston University researchers used data from satellites operated by NASA and the U.S. Geological Survey that gather land surface temperatures. These pass across the Chicago area at approximately the same time every 16 days, making it possible to track trends.
The team used 35 separate days of high-quality satellite observations obtained over a decade, from 2013 to 2022, to identify census block groups where average land temperatures were hotter or cooler than at least 90% of the rest of Chicago, then using census data to look at who lives there.
In addition to racial and ethnic differences, residents of areas with the hottest average surface temperatures include around 80,000 people without health insurance, 9,000 families in poverty and 24,000 seniors who live alone, according to the Tribune’s analysis of census estimates.
“Areas where the residential areas are largely poor and, of course, majority-minority communities … those neighborhoods that have the highest exposure to heat also have the highest vulnerability, the least access to cooling centers, the least social affluence,” said Illinois state climatologist Trent Ford.
The federal government’s former discriminatory practice of redlining, which rated areas as “hazardous” based largely on the number of Black and immigrant residents who lived there, has been linked to hotter temperatures in cities across the country.
Ford also noted that the communities with the most heat tend to have the most industry. The presence of warehouses reduces the land available for green space and can inflate nearby temperatures, he said.
“The physics of the urban heat island effect are very simple. …. The more paved over and treeless and less natural the environment, generally speaking, you’re going to have higher temperatures,” said climate scientist Jeremy Hoffman, who helped map heat in Richmond, Virginia.
Raising the stakes for human health, industrial operations also bring more air pollution to the neighborhoods in which they’re located. Operations such as metal shredding and asphalt production produce emissions, while warehouses and truck and train terminals in industrial corridors bring constant freight traffic to nearby communities.
The Tribune found the city’s coolest areas have an average rating of 30 on the Chicago Public Health Department Air Quality Health Index, a measure in which zero represents the best air quality and 100 the worst. The average in Chicago hot spots is more than twice that, at 70.
Combined exposure to heat and air pollution elevates the risk of a range of dramatic health impacts, including cardiovascular disease, respiratory disease, diabetes and birth defects, said Susan Anenberg, director of George Washington University’s Climate and Health Institute.
As chair of environmental justice at Pilsen’s St. Paul Catholic Church, Mary Gonzalez has been working with advocates from 15 other groups to pressure the city and state to deny a permit that would allow a controversial metal shredding and processing company, Sims Metal Management, to restart its operations in Pilsen.
Symptoms of a chronic lung disease mark many of Gonzalez’s days in retirement. “It just makes me angry that I have to put up with a lung disease because I live in the neighborhood that I have loved for the last 70 years,” said Gonzalez, 82. “We’re sacrificial communities. We don’t want to be.”
Jim Schwab, of Logan Square, lives in a census block group with less extreme summer surface temperatures, according to the analysis by the Tribune and Boston University. A 100-year-old tree helps keep his home cool throughout the summer, Schwab said, as trees do for many of his neighbors.
Schwab, retired from a job with the American Planning Association, cautioned residents who live where it’s cooler not to trivialize the temperature differences in Chicago’s hotter areas. “There’s a humanitarian aspect to this that I think escapes a lot of people’s attention,” he said.
“What you’re doing to some degree is kind of sentencing people in other areas to live in zones that are much more subject to extreme heat,” he said. “If you’ve ever actually walked through some of those areas, on a hot day, you’d start to very quickly find out what it really feels like.”
A father of five, Juan Antonio Espinosa told the Tribune last year that although his family has two secondhand air conditioners in their Brighton Park apartment, the window units don’t work well — and he and his wife don’t make enough money to afford to regularly use them. They were living at the time among the city’s hottest average surface temperatures.
“The bills don’t wait and sometimes I fall behind. If we fall behind too much, they suspend our service, and it’s complicated when you have kids,” said Espinosa.
Blocks from Espinosa’s home, trucks rumble through the Brighton Park industrial corridor, which stretches across 400 acres to nearby Gage Park. Antonio Santos, who grew up in that neighborhood, said the sprawling footprint of industry not only traps heat, it traps residents who have few places they can find relief.
One of the largest grassy areas in Gage Park, he noted, is the parkway in the middle of Western Avenue, bare except for memorials for community members who have died.
Instead of investment in the community’s land use needs, Santos said, “we see an obvious investment toward industry. We don’t have any green spaces that produce food. We don’t have many community gardens.”
Given the differences in urban climates and community preferences, there’s no universal approach to fighting extreme heat. But Espinosa and Santos are raising two key issues, experts said: Green space is integral to reversing the heat island effect, while improving access to air conditioning is the surest means to save lives.
Parks may provide “the greatest bang for your buck” among climate interventions, said Anenberg, the George Washington University climate health expert. Lack of green space has been linked to increased mortality, adverse mental health impacts and preterm birth, while research shows improved access to green space increases exercise and health, she said.
In Gage Park, Santos said: “What we see are young children literally playing in parking lots. We see kids after school riding their bikes in parking lots. We see them playing soccer in parking lots, because there aren’t green spaces near their schools. They’re playing among semi-trucks and commercial railroad tracks.”
Disparities in green space send an unspoken message, Santos said: “We aren’t worthy of the things that other people are worthy of. And I think that starts very young.”
Green space can be created in ways large and small, said Hoffman, the Virginia scientist, from “de-paving” portions of parking lots to transferring vacant city-owned parcels to public land — as the city of Richmond has done. Detroit, Houston and St. Louis are among other cities that have similarly donated vacant parcels to create public green spaces.
The city of Chicago, which owns more than 10,000 vacant lots, launched a program in late November to facilitate the redevelopment of around 2,000 of them. Residents can purchase those lots and take on property taxes and maintenance costs to create open space.
The parcels are being sold at a steep discount. But Alberto “Chichimeca” Rodriguez, who like Santos is a member of the Gage Park Latinx Council, said it doesn’t seem fair that communities must pay out of pocket to create more parks.
Hoffman and other experts also said such nature-based interventions may not be enough to protect people. “Air conditioning is the principal way that we can keep people safe in an extreme heat scenario,” said Hoffman, adding that the emissions produced by cooling shouldn’t be a reason to deny access.
Legislation now awaiting Gov. J.B. Pritzker’s signature will ensure Illinois residents of state-funded housing have air conditioning, if enacted. But rising energy costs have made it harder for working families everywhere to afford their utility bills. More than 500,000 Illinois residents couldn’t pay an energy bill in certain months of the year, the U.S. Census Bureau estimated in December 2021; nearly 400,000 also said the temperatures in their home were at times unsafe.
Cooling assistance is provided in some states via the federally funded Low Income Home Energy Assistance Program. But Illinois’ LIHEAP plan doesn’t include cooling. Many residents seeking relief from the heat who spoke with the Tribune last summer had no air conditioning or nonfunctioning units and needed assistance to pay for the cost.
For people who live in heat islands, temperatures are more intense and take longer to cool off at night. “Sometimes we can’t even sleep,” Espinosa said.
The aggravating effect of combined exposure to heat and air pollution is relevant not only to his twin daughters’ asthma but also his wife’s diabetes. Heat affects blood sugar, and diabetes complications make it harder for the body to regulate temperature and stay hydrated, according to the Centers for Disease Control and Prevention.
“Everything is worrisome, especially when it deals with the family and the kids,” Espinosa said. “I think the city can do a lot more (to help) not only my family but many families who are also low-income, just like us.”
When days of intense heat arrive, Chicago agencies warn of the dangers of exposure and advertise the location of cooling centers. But for many people, there is little escape from the sun blazing overhead, triple-digit temperatures in the air and asphalt radiating heat below.
During one heat advisory day last year, a tiny library served as the only public source of cooling in Gage Park, a community where around 28,000 families live in poverty, according to 2020 census data.
At an unsheltered bus stop in Little Village, a rush-hour crowd spilled out from the shade of a nearby gas station on a June day that turned out to be the hottest of 2022. The predominantly Latino neighborhood is home to the city’s second-highest grossing shopping district, but bus shelters there are scarce compared with the respite provided commuters along the Magnificent Mile downtown.
Less than a quarter of Chicago bus stops have shelters, and these sources of shade are more than twice as abundant in areas with more white people that tend to be coolest, the Tribune’s analysis of Chicago Transit Authority and census data found. Areas where bus shelters are nonexistent tend to be hotter and home to more nonwhite people.
Rich Guidice, who served as head of the Office of Emergency Management Communications under Lightfoot, will bring heat management experience to Johnson’s administration as the new mayor’s chief of staff. That agency has helmed the city’s response to National Weather Service advisories since the Richard M. Daley administration.
But increased temperatures may demand improvements to city strategies deployed for the past three administrations. According to a Boston University analysis, nearly half of Chicagoans live more than a half-mile’s walk from the nearest of the six cooling centers that the city offers on heat advisory days.
Even after taking into account the air-conditioned libraries and police stations and Park District sprinklers that the city also promotes in hot weather, substantial pockets of the Chicago communities most vulnerable to heat stress remain without ready access to any cooling resource, the Boston researchers found. Many residents also may not feel comfortable seeking refuge inside police stations or soaking themselves in public to cool off.
Reacting to heat waves also isn’t enough on its own to create resilient communities, experts said. “We need to make heat a hazard that we incorporate into all of our planning efforts, that we consider year round,” said Meerow, of Arizona State.
“Addressing heat holistically is going to include heat mitigation, where we’re actually trying to cool areas, and heat management, which is: ‘How do we actually cope with and make sure that people aren’t suffering from the heat that we’re not able to ultimately mitigate?’” she said.
[ Visit the Chicago data dashboard created by Boston University’s Center for Climate and Health ]
In early May, as Johnson prepared to take the helm at City Hall, a spokesperson said he “is committed to improving climate health for all Chicagoans and their communities.” The spokesperson said Johnson is assembling a team to examine current policies and “what will be necessary to chart a course for long-term sustainability and success” and couldn’t yet elaborate on how the administration will assess heat strategies and disparities.
Given the city and state’s patchwork approach to cooling protections, Johnson’s promise to “establish robust and non-onerous assistance programs to reduce utility-burdened households to zero” and to provide protection against utility shut-offs is notable. But his spokesperson declined to say whether cooling would be part of a new “Clean and Healthy Buildings” ordinance that Johnson heralded during his campaign. Currently the city guarantees a safe minimum temperature in renters’ homes in the winter but offers no such protection in the heat of summer.
The climate action plan Lightfoot introduced last year included no mention of air conditioning nor specifics on providing shade to commuters and walkers, and the Heat Vulnerability Index it promised has yet to be released. Lightfoot’s administration later launched a grant program to support “neighborhood projects that mitigate the effects of climate change,” though these are limited to projects related to energy efficiency, electric vehicles and stormwater infrastructure.
Lightfoot did keep pace with her commitment to plant 75,000 trees over five years, prioritizing certain neighborhoods in an effort to reduce disparities, according to city documents. But while trees have many potential benefits, which include absorbing heat and filtering the air, climate researchers say they aren’t always the most efficient or effective means to cool community temperatures or provide shade. Since trees require time to mature and proper maintenance, Meerow said it can be strategic to also provide shade in other ways, such as sidewalk structures.
Another Lightfoot focus, green roofs, may not always be the most effective means to cool temperatures, either. When installed in the wrong areas, green roofs can produce such unwanted consequences as shortening the reach of the Lake Michigan breeze, according to a climatologist who ran simulations on the expansion of green roofs in Chicago. The relationship between vegetation, temperature and air circulation is complex, said Ashish Sharma of the University of Illinois at Urbana-Champaign.
“You can’t just place them blindly; you need to find strategic locations,” said Sharma, who said his models did identify tracts where green roofs could help.
A recent NASA study also found that placing a green roof atop a Humboldt Park Wal-Mart didn’t prevent temperatures from rising at the formerly vegetated site, suggesting that green roofs may not be an adequate substitute for open space. Green roofs, unlike parks, also aren’t generally accessible to city residents.
Fighting the effects of extreme heat demands a variety of interventions, said Hoffman, who likens the options to a buffet. “Too many places are choosing to take just one item out of that buffet, when we should really be finding what fits best with … the appetites of all of our residents in different parts of the city.”
In Gage Park, under Rodriguez, the Latinx Council’s Reclaiming our Roots program began working with neighborhood youths in 2021 to create a green space as a respite from the industry that surrounds them. Tucked in a residential block near one of the two Amazon facilities in Gage Park, the group’s Heritage Garden covers multiple lots on 53rd Place and Homan Avenue.
“We’re trying to fix damage that was never created by us,” Rodriguez said. “We are owed a lot by those who created this damage in the first place.”
Former Tribune reporter Stephanie Casanova contributed.