Greg Hess, the medical examiner for Pima County, Arizona, faces an escalating public health challenge every year between April and October as morgue drawers fill with victims of extreme desert heat. While federal agencies and researchers lack a consistent system to track climate-fueled fatalities nationwide, Hess and his team are pioneering innovative protocols along the U.S.–Mexico border to accurately count heat-related deaths and redefine how communities understand the true human cost of climate change.
Inside the Pima County Medical Examiner’s Office
Dealings with mortality define each day for Greg Hess. As lead medical examiner for Pima County, Ariz., Hess oversees an office handling roughly 3,000 cases annually—ranging from quiet natural passings to tragic overdoses and gruesome scenes. Yet the summer months bring a distinct, relentless surge. Pima County is hot, though not explicitly the hottest, biggest, most humid, or most populated region in the United States. Even so, Hess and his personnel sit at the nation’s forefront for developing precise methodologies to isolate and measure the lethal impact of extreme heat.
Hess arrived in the desert by way of Wisconsin, where he grew up with a ruddy-cheeked complexion, and a stint as an Air Force doctor in California. Outside the autopsy suite, he maintains an active routine, commuting by bicycle through scorching summer temperatures and holding the office title for an ongoing internal pickleball tournament—complete with a silvery desktop trophy holding a single ball and a stamped label reading “CHAMPION,” as reported by NPR. Drawn to forensic pathology during medical school rotations that peers often avoided, Hess found fascination in the silent stories held within human remains on the examination table.
The National Blind Spot on Climate-Fueled Fatalities
The protocols developed in Tucson address a glaring deficiency across the United States. According to public health experts, no official government agency, academic researcher, or state institution consistently tracks the total scope of climate-worsened disasters, whether from intense heat waves, intensifying hurricanes, or choking wildfire smoke. Kristie Ebi, a public health and climate epidemiologist at the University of Washington, notes that these statistical omissions carry profound consequences for families and municipal planners alike.
“If you don’t know how many people suffer and die in disasters, then you can’t set priorities appropriately,” Ebi explained, highlighting how incomplete mortality figures impair local governments’ ability to deploy life-saving interventions, such as strategically placing cooling centers during historic heat events. Without precise figures, the true human toll of severe weather remains obscured, preventing cities from allocating resources where they are needed most.
Data-Driven Strategies to Save Lives
The push for better tracking unites a diverse coalition of forensic specialists, epidemiologists, and public health advocates. By refining how coroners and medical examiners record the underlying and contributing factors of high-temperature fatalities, these professionals aim to provide actionable intelligence to city leaders and policymakers. As global temperatures climb toward unprecedented thresholds, the methodologies forged in Pima County offer a blueprint for municipalities seeking to measure risk, protect vulnerable populations, and confront the mounting realities of a warming planet.
