heat index

Commercial devices like this are available to calculate the heat index, that is, how hot it actually feels given the humidity. But the algorithm used to compute the heat index breaks down under extreme conditions of temperature and humidity, underestimating the stress on the human body. (credit: Yi-Chuan Lu, UC Berkeley)

BERKELEY, Calif. — A dire new study of hot weather in Texas is showing the true dangers of rising temperatures due to climate change. Scientists at the University of California-Berkeley are revealing that the heat index, or the “feels-like” temperature, is climbing at an alarming rate — approximately three times faster than recorded temperature increases.

This revelation, published in the journal Environmental Research Letters, points to a critical gap in public awareness regarding the true dangers of rising temperatures in the era of climate change. Study author David Romps, a professor of earth and planetary science at the UC Berkeley, highlights a pressing issue: the standard temperature readings do not fully capture the heat stress experienced by individuals.

💡Problems With The Heat Index

The heat index, which factors in relative humidity to determine how hot it actually feels, offers a conservative estimate, yet still falls short of conveying the heightened risk of heat-related illnesses on exceptionally hot days. This discrepancy can lead to a dangerous underestimation of hyperthermia risks — where the body overheats to dangerous levels — and the likelihood of heat-induced fatalities.

The research, drawing on Texas temperature data from the summer of 2023, sheds light on the inadequacy of current methods used by government agencies to calculate the heat index. These methods, Romps argues, fail to account for the extreme temperature and humidity levels now becoming more common due to climate change. This oversight could explain the surge in heat-associated deaths, as seen in Arizona’s Maricopa County, where fatalities rose by 50 percent from 2022 to 2023, predominantly affecting individuals over 50 years of age.

“I mean, the obvious thing to do is to cease additional warming, because this is not going to get better unless we stop burning fossil fuels,” says Romps in a university release. “That’s message No. 1, without doubt. We have only one direction we can really be taking the planet’s average temperature, and that’s up. And that’s through additional burning of fossil fuels. So that’s gotta stop and stop fast.”

heatwave man sweating
Scientists are revealing that the heat index, or the “feels-like” temperature, is climbing at an alarming rate — approximately three times faster than recorded temperature increases. (Photo by Ketut Subiyanto from Pexels)

Romps points out that the constant relative humidity levels, coupled with rising temperatures, hamper the body’s ability to cool itself through sweating, exacerbating the heat stress experienced during heat waves. To cope with the irreversible impacts of global warming already in play, Romps advises practical measures for individuals to mitigate hyperthermia risks.

“You can coat yourself in water. Get a wet rag, run it under the faucet, get your skin wet and get in front of a fan,” explains Romps. “As long as you are drinking enough water and you can keep that skin wetted in front of the fan, you’re doing a good thing for yourself.”

The study employs extended calculations of the heat index to encompass all possible combinations of temperature and humidity. This approach reveals the extreme “feels-like” temperatures Texans faced in the summer of 2023, with an astounding heat index calculation of 167 degrees Fahrenheit at Houston’s Ellington Airport on July 23, 2023 — attributing a 12-degree Fahrenheit increase directly to global warming.

“It sounds completely insane,” notes Romps. “It’s beyond the physiological capacity of a young, healthy person to maintain a standard core temperature. We think it’s hyperthermic, but survivable.”

These findings not only challenge the existing threshold for survivable temperatures but also call for a reevaluation of heat index calculations to better predict and communicate the risks of heat waves.

“If humanity goes ahead and burns the fossil fuel available to it, then it is conceivable that half of Earth’s population would be exposed to unavoidably hyperthermic conditions, even for young, healthy adults,” concludes Romps. “People who aren’t young and healthy would be suffering even more, as would people who are laboring or are out in the sun — all of them would be suffering potentially life-threatening levels of heat stress.”

StudyFinds’ Matt Higgins contributed to this report.

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  1. Emory Kendrick says:

    Drivel. This dolt and his fellow ‘researchers’ need to study climate history. We have had severe heat waves and ‘record’ temps since the beginning of recorded weather and long before the industrial revolution.

  2. Max says:

    When the weather is unusually cold it’s nothing to do with GW, or “Climate Change causes cold weather”, yet when it’s hot it’s proof amiright? I’ve been convinced for decades the climate crisis thingy is propaganda made up by the UN/WEF to give them a political issue to gain them power. It has to be something affecting the entire planet, it has to be an emergency and GW is perfect. They learned from Hitler and whomever he learned from before that to propagandize children, repeat the lie incessantly, etc

    I do feel sorry for Texans though, I woke one April morning and decided that I had to get out of there before July so I got in my car and drove 22 hours straight to Isla Vista CA, lived in my car for awhile, that’s how much I hated Texas and the weather… If the grid ever goes down for a whole summer lots of people in Texas will die. The first explorers to go to the Gulf area [from Boston area] declared it uninhabitable, they were correct.

    1. Emory Kendrick says:

      I live here. It does get hot but you get used to it. Coming from FL, I am quite used to the heat …an it actually feels less hot here due to lower humidity. I don’t use AC a lot….never have. I grew up without it and have not gotten used to it in my 74 years.