Science Snippets: Human Lives Shortened by Extreme Heat

Draft script:

I have reported many of the impacts of climate change, including generally increased temperature, more variable weather, and more precipitation. I have described the likelihood of loss of habitat for many organisms, including humans. From Time ezine comes yet another undesirable outcome of anthropogenic climate change.

An article published 27 August 2025 is titled Extreme Heat May Make You Age Faster. Here’s the lede, followed by an additional sentence to complete the first paragraph: “Everyone has felt the exhaustion and dehydration that comes with spending too much time in the heat. But research shows that the impact of being exposed to extreme heat goes beyond heat waves: consistent exposure to high temperatures might also be making you age more quickly.”

The article at Time refers to a peer-reviewed paper in the second paragraph: “A new study, published Aug. 26 in the journal Nature Climate Change, found that repeated exposure to heat waves was linked to accelerated aging and increases vulnerability to health issues. The more extreme heat events an individual was exposed to, the more their bodies aged.”

The peer-reviewed paper is not open-access. It was published as part of the renowned Nature series of peer-reviewed publications on 26 August 2025. Written by one scholar, it is titled Repeated heatwaves can age you as much as smoking or drinking. The subhead reads “Long-term study suggests that the more heatwaves people are exposed to, the more it accelerates body ageing.” It is based on a long-term study of 24,922 people in Taiwan. The story in Time provides sufficient information to reach the same conclusion as the peer-reviewed paper.

Back to the study in Time, we find an overview of the peer-reviewed paper: “Researchers analyzed medical data from nearly 25,000 people in Taiwan over the course of 15 years: between 2008 and 2022, when the region experienced 30 heat waves (defined by the researchers as a ‘period of elevated temperature over several days’). They were able to calculate a person’s biological age by using results from several medical tests including assessments of liver, lung, and kidney function; blood pressure; and inflammation. They then used participants’ addresses in the two years before their medical visit to compare their biological ages to the temperatures that they were likely exposed to.”

The findings are summarized in the following short paragraph: “They found that the more extreme heat events a person endured, the more quickly they aged, with every extra 1.3°C of total cumulative heat adding around eight to twelve days to their biological age. Manual laborers and those living in rural areas experienced the largest health impacts.”

The final two paragraphs of the story at Time provides an overview, embedded links to two more research studies, and the bottom line: “Climate change is making extreme heat events more common around the world. 2024 was the hottest year on record, topping the record set in 2023. A Climate Central study found that 88% of 247 major U.S. cities have seen an increase in the number of extremely hot days since 1970.

Climate models show that global temperatures will only continue to rise, with the World Meteorological Organization estimating a 70% chance that the five-year average warming for 2025 to 2029 will be more than 1.5 °C. Creating solutions to combat extreme heat is only going to become more imperative as temperatures increase, experts say.”

The embedded link to the Climate Central study takes the reader to a story headlined Climate Change Driving 55-year rise in Extremely Hot Summer Days. Published 4 June 2025, the story opens with five KEY FACTS expressed as bullet points:

First, “As heat-trapping pollution continues to warm the planet, summers are getting hotter and heat extremes are becoming more frequent—putting health as risk.”

Second, “New attribution analysis shows that climate change is having a growing influence on the frequency of extremely hot summer days in 88% of 247 major U.S. cities analyzed since 1970.”

Third, “On average, these cities currently experience about six extremely hot summer days with a strong climate change fingerprint each year, compared to zero such days during the 1970s.”

Fourth, “Seven of the top 10 cities with the largest increases in climate change-fueled extremely hot summer days are located in the South, mainly in Texas.”

Fifth and finally, “Heat is the leading cause of weather-related deaths in the U.S. The rising frequency of extreme heat due to climate change puts public health at risk from heat-related illness.”

The embedded link to the World Meteorological Organization study takes the reader to a story headlined Global climate predictions show temperatures expected to remain at or near record levels in coming 5 years. Published 28 May 2025, this story begins with a one-sentence overview: “Global climate predictions show temperatures are expected to continue at or near record levels in the next five years, increasing climate risks and impacts on societies, economies and sustainable development, according to a new report from the World Meteorological Organization.” Six Key messages are then presented as bullet points:

One, “80% chance that at least one of the next five years will exceed 2024 as the warmest on record.”

Two, “86% chance that at least one of next five years will be more than 1.5°C above the 1850-1900 average.”

Three, “70% chance that 5-year average warming for 2025-2029 will be more than 1.5 °C.”

Four, “Long-term warming (averaged over decades) remains below 1.5°C.”

Five, “Arctic warming predicted to continue to outstrip global average.”

Sixth and finally, “Precipitation patterns have big regional variations.”

Each of these six bullet points has been proven accurate. Each year tends to be warmer than the last. The heating at the poles exceeds that of the overall planet. And precipitation is increasing, albeit with large regional variations. The ongoing accumulation of data tells the same story I’ve been rattling on about for several years: Our time is short. As always, I recommend living accordingly.