Another summer of extreme heat is ahead—and you’ll feel every degree of it
A recent study finds that humans are sensitive to even small temperature increases. Researchers hope the findings will influence how we tackle climate change.
In the annals of human history, a subtle but relentless pulse has marked our anthropogenic impact on Earth. Since the industrial revolution dawned in 1850, our planet has steadily warmed each year , with the rate tripling since 1982. By the year 2050, experts estimate we’ll see a 2.7 degree Celsius average temperature rise—and a cascade of ecological repercussions.
2023 etched its fiery signature as the hottest year on record—and forecasts for summer 2024 are already predicting extreme heat across the United States and Europe. And, recent research suggests that you are going to feel every single degree of it.
(Extreme heat can be deadly—here’s how to know if you’re at risk.)
According to the study published in the journal Scientific Reports, humans are even more sensitive to temperature shifts than previously thought: Indeed, we can perceive temperature differences as small as 0.9°C with surprising accuracy. “Whether or not you’re aware of it, you are actually sensitive to it biologically,” says Laura Battistel, a cognitive and brain sciences student at the University of Trento who led the study.
And that could make a difference in how we tackle climate change.
While it's crucial to note that the real impact of temperature shifts lies in how they disrupt environmental and weather systems, Battistel hopes that her research will help people understand just how keenly they really will feel even a one-degree Celsius temperature change due to global warming—which could perhaps inspire them to care about climate change solutions.
How the human body adapt to heat
Human bodies are meticulously regulated to maintain an internal temperature of around 37 °C, vital not just for physical well-being but also for cognitive processes. Extreme temperatures, whether scorching or freezing, pose significant health risks such as heat stroke or hypothermia. Our evolutionary path has finely attuned us to temperature fluctuations for our survival. Detecting even minor shifts likely served as an early warning system, prompting actions like seeking shelter, adjusting clothing, and adapting behaviors to stay comfortable.
But these adjustments can only go so far. The pace and magnitude of contemporary climate change present unprecedented challenges. Rapidly escalating temperatures, coupled with environmental disruptions, strain our adaptive capacities and require us to take proactive measures to mitigate impacts.
Battistel was inspired to research just how attuned we are to temperature changes after noticing a lack of literature on the psychology of it. “There was nothing about it—are we aware of the changes? How good are we at detecting these changes?”
In the study, Battistel and her team asked participants to walk between two climate-controlled chambers, which had a maximum difference of two degrees Celsius. What they found was that the participants' response was surprisingly accurate—they were able to detect less than a full degree of temperature change, and more likely than not, guessed that the temperature difference was greater than it was.
“It tells us a story of how disconnected we are from our environment. Our bodies are connected, and yet our awareness is not so connected,” says Battistel.
While the researchers note that the study was fairly preliminary and didn’t ask participants which chamber they preferred in terms of comfort, they emphasize that studies like this one can inform energy models, guiding future energy usage and potentially promoting more sustainable practices.
“Our curiosity extends to unraveling how our bodies interpret signals to form our perception of temperature,” says Riccardo Parin, an engineer who co-authored the study. “This exploration holds the promise of revealing profound insights into the complex processes governing our sensory experiences.”
Energy usage and sustainability
One thing that’s clear from the scientific literature, Parin says, is that health risks escalate as temperatures rise beyond certain thresholds. “This means we might need to use more and more energy to stay comfortable as temperatures rise,” he says.
Parin argues that having a better understanding of human sensitivity to temperature changes could drive advancements in technology for climate control systems, which rely on algorithms to optimize settings based on occupants' comfort levels. This knowledge could allow for the development of highly precise sensors that can detect subtle temperature variations, ultimately leading to more efficient heating and cooling systems in homes.
But while UCLA climate scientist Daniel Swain finds the recent research compelling, he notes that the effects on our bodies are hardly the worst part of climate change.
“It is interesting that we do seem to be able to perceive pretty small fractions of a degree centigrade differences, which tells us something about perception,” Swain says. “The challenge with extending it to climate change is that the main reason that we’re so worried about degrees of warming is not the actual warming itself—it’s those numbers serving as an indirect indicator of much bigger, more consequential changes that are going to occur and those levels of warming with respect to almost everything else.”
(These real solutions could help us fight climate change.)
The true climate challenge resides in the broader scope of Earth's interconnected systems. Climate change is already transforming our world, from the rise in extreme weather events like hurricanes and heatwaves to reshaped ecosystems such as coral reefs and Arctic ice. It’s going to take comprehensive solutions like transitioning to renewable energy sources, implementing large-scale reforestation projects, and adopting sustainable agricultural practices to avert the worst impacts.
Now we understand how acutely we’re going to feel it—but are we going to take action?
