Climate change affects how we feel, not just how we live

Heat doesn’t just make us sweat – it also changes how we feel. Blistering heat can shift our emotions and scientists are now able to quantify the changes.

A massive study of social media data revealed that individuals become significantly more irritable in extreme heat. The research implies that rising temperatures may directly affect the emotional health of millions of people around the world.

How heat changes emotions 

The researchers reviewed 1.2 billion social media posts from 157 countries, all posted during 2019. They used advanced computer programs to analyze posts written in 65 different languages, giving each post a score based on how positive or negative it sounded.

The team matched these mood scores with local weather data to see how temperature affected what people were saying online.

The results were clear and consistent across the world. When temperatures rose above 95 degrees Fahrenheit, people’s posts became about 25 percent more negative in lower-income countries. In wealthier countries, the negativity increased by about 8 percent.

“Social media data provides us with an unprecedented window into human emotions across cultures and continents,” said Jianghao Wang from the Chinese Academy of Sciences (CAS).

“This approach allows us to measure emotional impacts of climate change at a scale that traditional surveys simply cannot achieve, giving us real-time insights into how temperature affects human sentiment worldwide.”

The inequality of heat’s impact

The researchers used World Bank data to separate countries by income levels, with the dividing line set at $13,845 per person per year. Countries below this threshold showed emotional responses to heat that were stronger than those in wealthier nations.

This makes sense considering that richer countries have more air conditioning, better healthcare, and stronger infrastructure to deal with extreme weather.

“Thanks to the global coverage of our data, we find that people in low- and middle-income countries experience sentiment declines from extreme heat that are three times greater than those in high-income countries,” noted Yichun Fan of the Sustainable Urbanization Lab and Duke University.

“This underscores the importance of incorporating adaptation into future climate impact projections.”

Climate stress and human well-being

Siqi Zheng of MIT, who led the study along with colleagues from multiple international institutions, emphasized that the stakes go beyond economics or public health.

“Our study reveals that rising temperatures don’t just threaten physical health or economic productivity – they also affect how people feel, every day, all over the world,” said Zheng.

“This work opens up a new frontier in understanding how climate stress is shaping human well-being at a planetary scale.”

Emotions linked to heat

The researchers used something called Bidirectional Encoder Representations from Transformers (BERT) to analyze the social media posts.

This artificial intelligence system can understand the emotional tone of text written in dozens of languages, making it possible to compare feelings across different cultures and countries.

The team examined posts from both Twitter and Weibo, a popular Chinese social media platform. Each post received a sentiment score between 0.0 (very negative) and 1.0 (very positive).

The researchers then grouped these scores by location – 2,988 different places around the world – and compared them with local weather patterns.

Future emotional impacts of heat

The researchers didn’t stop at current conditions. They used climate models to predict how extreme heat might affect human emotions by the year 2100.

Even assuming people will adapt somewhat to higher temperatures over time, they project that emotional well-being will worsen by 2.3 percent due to heat alone by the end of the century.

“It’s clear now, with our present study adding to findings from prior studies, that weather alters sentiment on a global scale,” said Nick Obradovich from the Sustainable Urbanization Lab and the Laureate Institute for Brain Research in Tulsa.

“And as weather and climates change, helping individuals become more resilient to shocks to their emotional states will be an important component of overall societal adaptation.”

Climate change and human well-being

The research opens up entirely new ways of thinking about climate change. Most studies focus on physical health impacts, economic damage, or environmental destruction.

But this work shows that rising temperatures also attack our psychological well-being, creating a kind of emotional pollution that spreads across the planet.

The study has some limitations. Social media users aren’t perfectly representative of everyone – young children and elderly people use these platforms less than other age groups.

Ironically, these are often the people most vulnerable to extreme heat, which means the real emotional impact of hot weather might be even worse than the study captured.

Preparing for a warmer world

The research comes from the Global Sentiment project at MIT’s Sustainable Urbanization Lab.

The scientists have made their complete dataset available to other researchers, hoping it will help communities and policymakers prepare for a world that keeps getting hotter.

“We hope this resource helps researchers, policymakers, and communities better prepare for a warming world,” said Zheng.

As temperatures continue rising globally, understanding these emotional effects becomes more important.

The study suggests that climate change isn’t just an environmental problem or an economic challenge – it’s also a mental health crisis that hits the world’s poorest people the hardest.

—–

Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates. 

Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.

—–