Uncovering the Rising Risks of Heat-Related Illness: Key Concepts to Know
A new analysis by Climate Central has revealed alarming trends in the frequency of high heat index days across the United States. The risks of heat-related illness increase significantly when the heat index values reach 90°F and above. Since 1979, there has been a notable increase in the annual number of days with a heat index of at least 90°F in 201 U.S. locations analyzed by Climate Central, with an average increase of 10 days per year.
Nearly one-quarter of these locations now experience at least 14 more annual high heat index days compared to 1979. The regions most affected by this increase include the South, Southeast, Northwest, and Southwest. The top six locations with the highest increase in high heat index days were all in the South or Southeast, specifically in Texas, Florida, and Georgia.
The combination of extreme heat and high humidity poses a significant health risk, with the potential for heat stress and illness, and even fatal consequences. Heat is the leading cause of weather-related fatalities in the U.S., and climate change is exacerbating bouts of extreme heat, making them more frequent and intense.
When air temperatures approach normal body temperature, high relative humidity levels limit the body’s ability to cool off through sweating, leading to a feeling of increased heat. This can result in serious and potentially fatal heat stress and illness. Heat index values of 90°F and higher are particularly dangerous, increasing the likelihood of heat-related illnesses such as sunstroke, heat cramps, and heat exhaustion.
It is essential to understand the impact of extreme heat on public health, especially in vulnerable populations such as children, older adults, pregnant individuals, low-income communities, and those with pre-existing health conditions. Structural inequities can also contribute to higher heat exposure in certain communities, particularly among people of color and those living below the poverty line.
Preventing heat-related illnesses requires proper planning and preparation, as well as awareness of warning signs and symptoms. It is crucial to stay informed about heat alerts and forecasts in your area, and to take proactive measures to protect yourself and others from the dangers of extreme heat.
Experts in the field, such as Luis E. Ortiz, Gredia Huerta-Montañez, and John Balbus, are available for interviews and can provide valuable insights into the impacts of extreme heat on public health. Additionally, resources such as the Centers for Disease Control and Prevention and the National Integrated Heat Health Information System offer guidance on how to prepare for and respond to humid heat conditions.
As extreme heat events become more frequent and intense, it is essential to prioritize public health and safety by understanding the risks associated with high heat index days and taking proactive measures to mitigate their impact.