Record high temperatures across the South and Southwest, with little relief even at night, are likely to increase prison deaths and are linked to other hazards such as pests and disease, the Prison Policy Initiative reports in a new study summarizing the latest research. Using two datasets — annual deaths in state prisons from the Bureau of Justice Statistics, and hourly temperature data from the North American Land Data Assimilation System — the researchers looked at unusually high temperatures occurring in the summer months at the geographic location of prisons. The researchers found for every 10 degree increase above the prison location’s mean summer temperature, nearly 5% of deaths (from all causes) occurring there could be attributed to the heat. Even the days following a hotter-than-average day were associated with deaths, although the risk of heat-related death declined, suggesting that mitigating heat right away is crucial. An extreme heat day (one that falls within the hottest 10% of days for a particular location) was associated with a 3.5% increase in deaths. These extremely hot days had a delayed effect on suicides, which increased by 23% over the three days that followed. Two- and three-day heatwaves (defined as consecutive days of extreme heat) were even more dangerous, increasing deaths by 5.5% and 7.4%, respectively.
The impact of heat on mortality was highest in the Northeast. So, even though states like Texas get criticized for failing to provide air conditioning, more temperate states aren't off the hook. Heat and other extreme weather associated with climate change are intertwined with other biological and social threats to people in prisons. In Utah, for example, where a brand new prison recently opened near the wetlands of the Great Salt Lake, the mosquito infestation has gotten so bad that prison officials have been scrambling for solutions. The number of infectious disease outbreaks (by growing populations of mosquitoes and ticks, for example) has risen along with average global temperatures. There is some emerging evidence, for example, that climate change is contributing to a rise in Valley Fever, a deadly fungal infection that has plagued people imprisoned in the Southwest for years. As the weather warms, prisons will demonstrate the well-documented relationship between heat and violence. A July 2021 study found that unmitigated exposure to heat — even after accounting for dozens of other factors — increased violent events in Mississippi prisons.