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Deadly heat is threatening the lives of America’s ageing incarcerated population, who are trapped in increasingly hot and humid conditions as the climate emergency escalates, new research has found.
Almost 45% of detention facilities on the US mainland suffered a rise in hazardous heat days between 1982 and 2020, with the south most severely affected. People incarcerated in state-run facilities in Texas and Florida are the most exposed to dangerous conditions.
Hazardous heat refers to the number of days a year when the indoor maximum wet bulb globe temperature exceeds 28C (82F) – the safe humid-heat threshold set by the US National Institute for Occupational Safety and Health (Niosh) for acclimated populations under moderate workload.
In facilities where detainees were exposed to at least one hazardous day a year, the average (mean) number of hot-humid days jumped from 77 to 100 a year in four decades, according to the study published in Nature Sustainability.
“When temperatures rise, prisoners are sitting ducks, utterly powerless to protect themselves from lethal levels of heat and humidity. Building a prison without climate control is like building a prison without fire exits – it’s an invitation to disaster,” said David C Fathi, director of the National Prison Project at the American Civil Liberties Union (ACLU).
The current threat to the incarcerated population risk is probably even greater than the analysis suggests given that the past three summers have been among the hottest on record.
America’s incarcerated population is at high risk of heat-related morbidity and mortality due to their physical confinement, age, high rates of chronic physical and mental illness and a general lack of concern about their welfare by lawmakers – and society at large.
Researchers also found that detention facilities – jails, prisons, work camps and migrant detention centers – are often built in the least hospitable places, where there is little cooling vegetation and communities have limited political power to resist. In addition, concrete structures trap heat, making them harder to cool including at night when the body cannot recuperate until the temperature drops to 80F.
Carlee Purdum, assistant director of the Hazard Reduction & Recovery Center at Texas A&M, said: “Prisons are more vulnerable to extreme temperatures than other types of infrastructure … incarcerated people are experiencing severe heat-related illness and have higher rates of chronic health problems and diminished access to healthcare resources.”
Arizona, Nevada and California have the widest heat disparities between prisons and other locations. The greatest overall increase of hot and humid days relative to the state was at Webb county jail with 59 more days than the rest of Texas in 2020 compared with 1982.
“Prisons and other detention facilities are located in disproportionately hotter places because the idea of incarcerated people suffering from heat fits the retribution and punishment ethos of the US system,” said co-author Robbie Parks, assistant professor of environmental health sciences at Columbia University.
Deadly heatwaves have struck towns and cities across the US in recent years, and are likely to rise in frequency and intensity due to global heating. Those without access to air conditioning or other effective cooling tools such as shaded outdoor spaces are vulnerable to heat exhaustion and heatstroke, as well as potentially fatal complications from existing health conditions and prescribed medications.
Swamp coolers
Climate control has been standard in any new construction for decades, and almost 90% of US households have air conditioning. Yet 44 states do not universally provide air conditioning in adult detention facilities. Those that do, often install evaporative coolers – also known as swamp coolers – which are less effective especially when humidity is high.
The study by a coalition of researchers at Montana State, the University of Kansas, California and Columbia, found that overall 1.8 million incarcerated people – 90% of adult detainees – were exposed to at least one dangerously hot and humid day annually.
In 118 facilities, mostly concentrated in southern California, Arizona, Texas and inland Florida, incarcerated people experienced at least 75 very hot-humid days on average a year. In Starr county jail in south Texas, on average the wet-bulb temperature hit at least 28C on 126 days a year.
The greatest increase over time was in Florida, where incarcerated people experienced on average 22 more dangerously hot humid days in 2020 compared with 1982.
“It’s a simple truth that heat kills vulnerable people first,” said Jeff Goodell, author of The Heat Will Kill You First: Life and Death on a Scorched Planet. “As the climate crisis accelerates and extreme heatwaves become more commonplace, this study underscores that un-air-conditioned prisons will become ovens where people are literally cooked to death.
“Improving ventilation and cooling systems in US prisons isn’t expensive and it doesn’t require a breakthrough in quantum physics [but] it requires seeing incarcerated people as fellow humans worthy of being treated with decency and respect,” added Goodell.
Despite the growing threat posed by the climate crisis, experts still do not fully understand how outdoor temperatures and humidity translate to conditions inside prisons – the crucial first step in planning interventions to alleviate the mental and physical health implications for incarcerated people and prison workers, according to Purdum at Texas A&M.
Deadly heat is not just a problem for the south. The warming planet is making extreme weather conditions – hot and cold temperatures, and rainfall – increasingly erratic and unpredictable, striking in places that are ill prepared to cope. In 2021, several hundred excess deaths were attributed to a heat bomb over the Pacific north-west – a region that is not equipped for extreme heat.
The ACLU has brought successful legal challenges to heat risk at prisons and jails in Mississippi, Arizona and Wisconsin, on the basis that the conditions violate the eighth amendment on the US constitution which prohibits “cruel and unusual punishments”. In Wisconsin, a maximum-security prison was ordered to air-condition the cells to a temperature of 84F or below despite arguing that air conditioning would entice inmates at different jails to attack others in order to get a transfer.
Ed Markey, the Democratic senator representing Massachusetts, has introduced two bills to tackle deadly heat including the End Solitary Confinement Act which would help prevent incarcerated people from being exposed to extreme heat, often in small, poorly ventilated cells.
“Extreme heat poses an extreme health risk to people across the country, and we need a national response that addresses the dangers posed by rising temperatures for incarcerated people,” Markey said. “We cannot prioritize the climate without prioritizing justice, and we must pass my legislation to ensure our most vulnerable communities are protected from extreme temperatures.”