Climate change may have contributed to a quarter of ER visits for heat-related illness from 2018-25, study finds
- A new study estimates that at least a quarter of emergency room visits for heat-related illness in the U.S. from 2018 to 2025 may be attributable to human-caused climate change.
- Heat-related deaths in the United States increased by more than 50% between 2000 and 2020, with the Southern Plains region, including Texas, experiencing about 25% of heat-related ER visits due to climate change.
- Researchers used a method based on two decades of environmental science to estimate climate change’s impact on heat-related ER visits, highlighting the need for public health systems to adapt to changing climate conditions.
Across the country, at least a quarter of emergency room visits for heat-related illness may be attributable to human-caused climate change, researchers from Climate Central, a nonprofit group, estimate in a new study.
Published in the September issue of Climatic Change, a scientific journal, the researchers’ peer-reviewed analysis suggests climate change contributed to about 27% of heat-related ER visits in the U.S. during warm seasons from 2018 through 2025.
Heat-related illness is on the rise across the United States. Yale School of Public Health researchers found that heat-related deaths increased by more than 50% between 2000 and 2020.
“Our healthcare system is pretty strained, when we think of emergency medicine in particular,” said Kristina Dahl, vice president for science at Climate Central. “This data is giving us a baseline that we know we’d be building on if we continue warming our planet.”
Climate change’s impact on ER visits varies by region, Dahl’s team found. In the Southern Plains area containing Texas, Oklahoma, Arkansas, Louisiana and New Mexico, the researchers estimated human-caused climate change contributed about 25% to the rate of heat-related ER visits.
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While climate change generally contributed to a bigger share of the rate in regions with milder summers, the South still had a higher absolute rate due to human-caused climate change, researchers wrote. They estimated about 57 of every 100,000 ER visits in the region containing Texas were for climate change-contributed heat illnesses. On average, about 225 of every 100,000 ER visits in the region were heat-related.
Dahl said climate change’s contribution to heat-related illness will likely grow without major human actions to reverse course.
To calculate their results, Climate Central scientists estimated what temperatures might have looked like in a world without human-caused climate change. They used those temperatures to predict rates of ER visits for heat-related illness in the modeled world, and used the difference from actual visit rates as an indicator of climate change’s contributions. Dahl said this method is based on two decades of environmental science, and that there are well-established relationships between temperature and hospital visits for heat-related illness.
Still, the study’s methodology provides only a rough approximation of climate change’s impact on ER visits, said University of North Texas health professor Kai Zhang. His research group studies the impact of climate change on public health.
Data: Tracking extreme heat in North Texas
Humidity and weather variations within the study regions also play a role in ER visit rate estimates, Zhang said. And, because many hospital visits in which excessive heat played a role might be recorded with an alternative main complaint such as cardiovascular disease, official figures on heat-related ER visits are likely undercounts.
It’s hard to retroactively determine which specific deaths resulted from human-made climate change, but the broad shifts in weather that we are experiencing will most likely exacerbate not just heat-related, but other illnesses in the U.S., Zhang said.
“As a result of changing climate, we will see more and more extreme weather events,” Zhang said. “Extreme heat, extreme cold, hurricanes, flooding.”
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Dahl hopes her team’s research can help public health systems adapt to changing climate.
“Because most heat-related illnesses and deaths are preventable, there’s a lot we can do with this information to help reduce the burden of hot summers,” Dahl said.
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This article originally published at Climate change may have contributed to a quarter of ER visits for heat-related illness from 2018-25, study finds.