Heat-related deaths in the US have doubled in 25 years

The study, published on August 26 in the Journal of the American Medical Association, analyzed data from the Centers for Disease Control and Prevention (CDC) on deaths from 1999 to 2023 in which extreme heat was a primary or contributing factor. The researchers found that the number of heat-related deaths increased from 1,069 in 1999 to 2,325 in 2023, an increase of 117 percent. During this period, 2004 had the lowest number of heat-related deaths, with 311, while 2023 had the highest number, with 2,325.

Researchers from a group of schools, including the University of Texas at San Antonio and Pennsylvania State University, noted a sharp increase over the past seven years, which coincided with record global temperatures as the impacts of climate change became more severe. The study’s findings show that between 2016 and 2023, the age-specific mortality rate increased significantly, by 16.8 percent per year. The increase in recent years has reversed a previous downward trend in heat-related deaths.

The findings are consistent with global studies showing that rising temperatures due to climate change are contributing to the rise in deaths. According to the US National Oceanic and Atmospheric Administration, in 2023, the world’s average temperature was the warmest since records began in 1850. Heat-related illnesses, such as heat exhaustion or heatstroke, occur when the body cannot cool itself properly. This can cause damage to the brain and other vital organs, according to the CDC. The study authors warn that without intervention, this trend of rising heat-related deaths will continue as global temperatures rise.