Judith Foster has always enjoyed the warm weather. She used to spend long days basking in the sun’s comforting glow as a child in Jamaica. But when she moved to Boston’s Dorchester community in 1975, that glow didn’t feel the same.
“From the second I got here, I always noticed this heat,” Foster said. “It’s different, it feels manufactured.”
Lucas Pinto, 32, who has lived in the Ashmont Street area for eight years, plays his regular outdoor basketball tournaments in Harambee Park, located on Blue Hill Avenue where Dorchester meets Mattapan. On summer days, when it’s so hot his hair feels like it’s burning, he said he thinks to himself, “I can’t keep doing this, I’m gonna fucking die.”
Dacey Jackson used to take a 1.5 mile walk from her home on Dorchester’s Taft Street to UMass Boston, where she works as a program manager for the Civic Action Fellowship Program. But the streets she’d take lacked trees and greenspace. The walk was uncomfortable at best, blistering at worst. So, she stopped walking.
“I couldn’t do it anymore,” Jackson said during an interview, waiting for the “walk” sign as cars roared by on Columbia Road. “I just Uber to work every day; I have no choice.”
Boston is a city of hotspots. Certain parts of the city reach higher temperatures in the summer than areas that have tree-shaded streets, little air pollution, and wide open parks. And a growing body of research has found that historically marginalized communities are much more likely to be hotspots.
Years of racist policies and practices have made it so people of color are more likely to live in communities with higher air pollution and little greenspace, and sleep in unimproved homes lacking air conditioning.
Indeed, neighborhoods in Boston that were redlined — labeled risky investments because its residents were Black, immigrants, or Jewish — are “7.5°F hotter in the day, 3.6°F hotter at night, and have 20% less parkland and 40% less tree canopy than areas designated as A: Best,” according to the city’s 2022 Heat Resilience Plan.
Over 11 months, The Emancipator, in collaboration with Boston University’s Justice Media Computational Journalism co-Lab, examined data on Boston’s surface temperature, tree canopy, housing violations, 311 complaints and neighborhood demographics.
The analysis drew comparisons between public datasets to illustrate how redlining created the conditions that lowered tree cover, raised temperatures and made homes harder to cool down in minority communities in Boston.
In 20 interviews with city officials, experts, community activists and residents, The Emancipator looked into how that legacy plays into someone’s day-to-day life and the plans to make the city more resilient to the effects of extreme weather.
Turning up the heat on Boston’s low-income and minority communities
The following interactive map breaks down the geography of racial disparities with regard to heat exposure across Boston’s neighborhoods.
Use the check boxes on the left to explore how extreme heat is disproportionately impacting people living in historically redlined, low-income neighborhoods in Boston. And it’s only expected to get worse.
Decades of racist policies and practices have created hotspots around Boston where residents — mostly people of color — can’t escape the heat.
The city is taking steps to redress the damage that’s been done over decades. Reverend Mariama White-Hammond, Boston’s chief of Environment, Energy, and Open Space, is leading a set of initiatives that seek to prepare Boston’s most vulnerable for the effects of extreme heat. And she’s not using the old playbook.
“The reality is if we address climate by the same rules that we made other historic decisions, the same communities that have been left out before will be left out again,” White-Hammond said.
It’s a pattern seen across the country: Years of racist policies and practices have made it so people of color are more likely to live in communities with higher air pollution and little greenspace, and sleep in unimproved homes lacking air conditioning.
“Old housing stock, no cooling, ever-increasing heat,” said Adam Chapdelaine, deputy director of Green Ribbon Commission, a public-private partnership aiming to help the city become climate resilient. “That’s the recipe for danger.”
Cities are hotter than rural areas by definition. Vulnerable groups feel the effects more.
Heat doesn’t only come from the sun in a city like Boston. It’s created by people, cars, buses and trains. It gets trapped in the dark asphalt used to pave the roads and the concrete used to build the buildings, ultimately warming the surrounding air.
An urban heat island, as researchers call it, is partly the result of urban infrastructure that displaces trees and greenery, which otherwise would clean the air and provide valuable shade. In 2021, climate researchers found that on average within the city, Boston was about 7 degrees hotter than outlying areas.
That’s less of a problem during Boston’s famously cold winters than during a heat wave, which last year saw some of the city’s hottest recorded temperatures. These hot spells can be dangerous without proper prevention or intervention. During the 2022 heatwaves, Boston EMS said they saw a 15-20% rise in 911 calls. “Extreme heat makes the body work harder,” said Dr. Britta Lundberg, infectious diseases expert and Founder of Lundberg Health Advocates.
Combined with high levels of air pollution, Lundberg said extreme heat increases the incidence of heart attacks, strokes, and asthma exacerbations. It can also induce seizures in children and disrupt sleeping patterns. And dehydration, she added, does “exacerbate all of those things.”
Some of those effects are quantifiable: Neighborhoods with the highest temperatures see higher rates of impact among socially vulnerable groups, according to an analysis of census tract-level heat metrics from July 2019 and social vulnerability data collected by the city. About 28,000 people with medical illnesses that worsen during heat waves live in Roxbury, which sees temperatures 1 degree higher than the city’s median.
Buildings and property in formerly redlined neighborhoods — such as Dorchester, Roxbury and East Boston — received more citations between 2010 and 2023 than neighborhoods that weren’t redlined and categorized as “A: Best,”according to data from the city’s Inspectional Services Department.
Dorchester has the highest rate of violations, at least 1,136 going back to 2010 where buildings were labeled “Unsafe and Dangerous,” or “Unfit for Human Occupancy,” 4.6 times the average of other neighborhoods, according to the analysis.
On a hot day, those who can will turn on their fans or air-conditioning units. Those who can’t might walk to the nearest library or community center, which are often air-conditioned, or take a swim in a public pool.
But cooling centers aren’t open 24/7. In a home that can’t fully cool itself, it’s harder to sleep on warm nights, which Lundberg said can harm one’s physical and mental health. Living in those conditions, many people have sought relief by reporting their situation to the city.
Since 2017, between May and September, there were at least 70 calls to the non-emergency line, with people bringing forward a string of excessive indoor heat complaints, our analysis of 311 service requests revealed. Dorchester and Roxbury made up about a third of the residents’ pleas citywide.
Across neighborhoods, residents reported units and entire buildings reaching anywhere from 80 to 100 degrees, many pointing to unresponsive property owners and management, according to a review of 311 call notes obtained through a public records request. Some mentioned children and elderly people, others noted asthma conditions.
“It has reached 100 degrees or more in my unit. I’m not sure if this is considered a health hazard or public health violation,” reads a June 2017 report out of Fenway.
At the root of environmental justice.
A former state representative said reasons behind the disparity are linked to previous policymakers’ choices.
“Hotspots were invented because we are in a racist city dealing with the people they like the least,” said Byron Rushing, who represented the ninth Suffolk district from 1983 to 2019.
The federal government made the unprecedented move in 1934 to draft one of the first formal, nationwide housing policies to help struggling, low-income families during the Great Depression, gradually allowing many Americans to enter the middle class. But where many benefited from the program, many more were left out purely on the basis of their race.
‘Areas with a higher proportion of African Americans, for example, in places that had older housing stock – were not deemed as desirable or as profitable or as safe for extending mortgage loans’
Bev Wilson, associate professor of urban and environmental planning at the University of Virginia's School of Architecture
An agency Congress created around the time — the Home Owners’ Loan Corporation — drafted maps of cities across the U.S. and drew its borders based on the likelihood of foreclosure in a neighborhood. The primary factor was race. A typical map might see large swaths of red and yellow painted over neighborhoods with concentrated Black or immigrant populations — signaling to banks that those areas were considered “hazardous” for investment and were to be avoided. It wasn’t uncommon at the time for real estate agents to assess property values based on demographics; indeed, the most valuable neighborhood was usually the Whitest, and any action by a real estate agent to change that was considered an ethics violation.

Any realtor who introduced “members of any race or nationality” to a racially homogeneous neighborhood could lose their license, according to the 1924 code of ethics for the National Association of Realtors.
The Federal Housing Administration, created in 1934, took that philosophy and made it policy, refusing to insure loans in concentrated Black communities.
“Not surprisingly, poor neighborhoods – areas with a higher proportion of African Americans, for example, in places that had older housing stock – were not deemed as desirable or as profitable or as safe for extending mortgage loans,” said Bev Wilson, associate professor of urban and environmental planning at the University of Virginia’s School of Architecture.
As a result, minorities were cut out from one of the biggest welfare programs in the nation’s history, and inner-city neighborhoods suffered from chronic disinvestment. Homes fell into disrepair. Real estate agents who wanted a quick buck would sell those same homes to different families, wait until they fell behind on their mortgage payments — usually due to the costs they incurred repairing the homes – and then foreclose. The practice was called blockbusting, and its ramifications in Boston lasted well into the 1970s and 80s. As inner-city homes sat vacant, the suburbs prospered.
A path forward
In 1980, Foster and her three sisters moved to Euclid Street in Dorchester, where her mother still lives. She remembered looking out her window and seeing men in hard hats cut down trees.
“There was no one that came to say anything,” she said.
Sitting in Dorchester’s Codman Square Library, Foster recalled how kids used to flock there to cool down, one of the few places nearby where that was possible. Over 47 years, Foster witnessed several trends, with the decline of trees at the forefront.
Foster said she doesn’t want to see more trees cut down. But she said that simply planting more trees will not solve the problem. “Addressing how we got here” is the focus of her advocacy.
“For me, it’s not just about, ‘Oh, it’s too hot over here,’” said Foster. “Before we can get to, ‘Oh, it’s too hot, why is it too hot?’”
Boston officials are working to prepare the city for the effects of climate change while advancing policies “rooted in raising the visibility and centrality of injustices” that “resulted in the climate crisis,” said Oliver Sellers-Garcia, Boston’s Green New Deal director.
In 2022, the city published its Urban Forest Plan, a set of strategies that seeks to equitably expand tree canopy coverage across the city. Over time, that would mean more space for trees, including along streets, and a push to address disparities.
“We are making a conscious choice to focus first on bringing communities that have low canopy up to a baseline standard,” White-Hammond said.
Of course, she said, that’s easier said than done. Some neighborhoods, like Chinatown, have dense urban infrastructure, which makes finding space for greenery difficult.
It’s partly the result of how cities are developed, according to David Meshoulam, executive director and co-founder of Speak for the Trees, a Boston-based nonprofit focused on urban forestry.
“Old cities weren’t necessarily built thinking about greenscapes,” Meshoulam said.
He said places that already have lots of greenspace all tend to attract wealthier people, who generally have more time and resources and to advocate for and take care of trees.
“It’s sort of this loop,” he said. “How do you create an equitable forest when the geography itself is already so inequitable?”
White-Hammond said it takes a lot of creativity. “If we can get it right in some of those places that are tougher, we’ll have no problem in places that are easy.”
In Dorchester, about 22 percent of land is shaded by trees.
Comparing one street to the other, Jackson thought about how bleak it all looked, how hopeless it made her neighbors feel.
“It’s everything, the sidewalks are smaller, the physical environment is not made comfortable or pleasant to walk in,” she said.
Jackson has been around the block. She’s lived in both Brookline and Dorchester in the seven years she’s spent in Boston, and she has noticed the differences in the urban environment from one zip code to another.
“I think what is so interesting is how intentional everything is, right?” Jackson said. “In every way that it was structured, it was to benefit the people in that community.”
She thought of Dorchester, shifted in her office chair at UMass Boston and crossed her arms.
“When places are not like that, it’s also intentional,” she said.
To produce this story, The Emancipator partnered with the Justice Media Computational Journalism co-Lab, a collaboration between the Faculty of Computing & Data Sciences’ BU Spark! program, the College of Communication, and the BU Hub Cross-College Challenge. Contributing students were Daniel Skahill, Kendall Richards, Roberto Rodas-Herndon, and Hangqi Cui, with assistance from Technical Engineer Rachel Li, Data Solutions Engineer Michelle Voong and professors Brooke Williams, Osama Alshaykh, and Langdon White.
Methodology
Over 11 months, The Emancipator, in collaboration with Boston University’s Justice Media Computational Journalism co-Lab, examined data on Boston’s surface temperatures, tree coverage, property violations, 311 complaints and neighborhood demographics.
The analysis drew comparisons between public datasets to illustrate how redlining created the conditions that lowered tree cover, raised temperatures, and made homes harder to cool down in minority communities in Boston.
In 20 interviews with city officials, experts, community activists and residents, The Emancipator looked into how that legacy plays into residents’ day-to-day lives, and also looked at the plans to make the city more resilient to the effects of extreme weather.
We gathered block-by-block demographic details for each neighborhood in Boston based on the 2020 United States Census, as well as data from the Climate Ready Boston Social Vulnerability analysis, and compared them with data showing historically redlined neighborhoods, heat metrics and predictions, the city’s tree canopy change assessment, housing violations since 2010, as well 311 service request data and call notes about excessive heat going back to 2017.
Our analysis showed people of color are more likely to live in areas expected to experience more extreme heat and swelter under the highest temperatures in Boston during heat waves. Experts say the consequences can be uncomfortable at best, deadly at worst.
Boston isn’t alone. A growing body of evidence suggests that redlining and other forms of racist practice and policy played significant roles in creating environmental justice communities in cities across the U.S.