Ruben Berrios comprehends firsthand the harsh reality: in the context of extreme heat, one’s geographical location can be a matter of life or death.

At 66 years old, Berrios resides in Mott Haven, a lower-income enclave nestled in New York’s South Bronx, where more than 90% of the population is Latino or Black. Every summer, the South Bronx swelters, becoming one of the city’s most torrid areas, with temperatures soaring 8 degrees Fahrenheit (4.5 degrees Celsius) higher than the nearby affluent, predominantly white neighborhoods of the Upper West and East sides.

For Berrios and his community, the heat isn’t merely uncomfortable; it’s a silent menace, responsible for claiming an average of 350 lives annually among New Yorkers alone, as per city mortality reports. Reflecting on the devastating impact of a recent heat wave, Berrios solemnly recalled, “I lost two people. They were close to me.”

Across the United States, tens of millions of Americans contend with severe heat waves, where temperatures routinely exceed 90 degrees Fahrenheit (32 degrees Celsius). Yet, in major cities, the brunt of this heat disproportionately affects people of color and those with lower incomes. In New York City, for example, Black residents succumb to heat-related stress at double the rate of their white counterparts.

Bill Ulfelder, executive director of the Nature Conservancy in New York, underscored this alarming disparity, noting, “Only a quarter of New York City’s population is African American, but half of the deaths from heat are African Americans.” This stark inequity is mirrored in mortality records from urban centers nationwide, revealing that heat-related fatalities starkly correlate with racial and socioeconomic lines.

The tragic legacy of heat waves extends back decades. In 1995, a devastating heat wave in Chicago claimed the lives of 739 individuals, predominantly elderly, impoverished, and Black. Last year in Maricopa County, Arizona, encompassing Phoenix, despite Black residents constituting just 6.8% of the population, they accounted for 11% of heat-related fatalities.

Historian of science David Jones recounted heat waves in Memphis during the 1960s and 1980s, noting that elderly residents in public housing projects perished because they feared crime and refrained from opening windows or venturing outside.

Environmental justice advocates attribute these disparities to decades of discriminatory housing policies, notably redlining, a 1930s practice that graded neighborhoods based on investment potential, systematically denying mortgages to minority buyers. This legacy not only restricted resources but also deprived these communities of green spaces and trees, intensifying their vulnerability to extreme heat today.

The impacts of redlining are palpable in neighborhoods like Mott Haven, rated a “D” for “hazardous” by the Home Owners’ Loan Corp. in the 1930s, and neighboring Morrisania, stigmatized for “Negro and Puerto Rican infiltration” and “obsolete homes.” Today, the South Bronx grapples with some of the city’s sparsest per-capita green spaces, ensnared by power plants, waste facilities, and highways that saturate the area with noise and air pollution.

Arif Ullah, executive director of South Bronx Unite, condemned this environmental racism, observing, “The South Bronx is a glaring example of environmental injustice.” Residents endure elevated rates of infant mortality, cognitive disorders, heart disease, and asthma, leading to the area’s grim moniker, “asthma alley.”

Similar inequities persist nationwide. A 2022 Boston University analysis revealed that neighborhoods with higher Black or Hispanic populations were less likely to have access to air conditioning compared to predominantly white areas across 115 metropolitan regions.

In response to escalating temperatures, New York City Mayor Eric Adams activated the city’s heat emergency plan, deploying hundreds of air-conditioned facilities as cooling centers. Zach Iscol, commissioner of New York City Emergency Management, stressed the need to expand programs aiding low-income residents with heating and cooling needs, citing overwhelming demand with 21,000 applications this year alone.

Yet, for residents with limited mobility, accessing cooling centers or installing air conditioning, which amplifies outdoor temperatures, remains challenging. In neighborhoods like Brownsville, the South Bronx, and East Harlem, venturing outdoors during sweltering days exposes residents to risks ranging from crime to drug activity.

Amid these challenges, community resilience endures. Residents like Berrios find resourceful ways to cope, from using wet towels on their necks to utilizing public fountains and even opening fire hydrants to cool streets — survival strategies born out of necessity.

Looking forward, environmentalists advocate for planting more trees and creating green spaces to combat urban heat islands, where densely paved areas trap heat. Ulfelder emphasized the urgency of prioritizing lower-income communities of color for these initiatives, highlighting that neighborhoods predominantly of people of color have 33% less tree canopy than predominantly white neighborhoods, contributing to temperature differences as high as 13 degrees Fahrenheit (7 degrees Celsius) within just 2 miles.

In a positive stride, the New York City Council recently passed legislation enhancing tree cover and urban forests, aiming to boost tree canopy from 22% to 30% by 2035.

As Howard Shillingford, a janitor in the South Bronx, reflects on the unyielding heat, he remarks, “It’s never been this hot.” For him, navigating school stairwells during sweltering conditions feels akin to traversing ovens.

In confronting an uncertain climate future, historian David Jones cautions, “The heat waves in 2044 will be far worse than today’s.” This sobering forecast underscores the imperative to address systemic inequalities and fortify vulnerable communities against the mounting threat of extreme heat, ensuring that resilience and justice prevail in confronting an escalating climate crisis.