According to a recent study by the Potsdam Institute for Climate Impact Research (PIK)published in The Lancet Planetary Health, the aggressive behavior of Internet users increases when temperatures drop below 12°C and exceed 21°C. These results underline the impact of climate change on our society, which is still far too underestimated.
The authors of the study conducted a statistical analysis between 2014 and 2020 of more than four billion tweets in the United States.
According to the results of the analysis, extreme temperatures fuel aggressive speech online.
Among the tweets analyzed, approximately 75 million contained aggressive speech, that is to say discriminatory remarks towards a group or a targeted person, mainly of a racist or misogynistic nature.
According to the data from the analysis, the minimum number of hateful tweets was recorded at temperatures between 15 and 18°C. Nevertheless, temperatures above 42°C resulted in an increase in online aggressiveness of 22.5%. The study reveals that this is also valid for very cold temperatures. Indeed, aggressive messages jump by 12.5% when temperatures drop between –6 and –3°C.
This study highlights the limits of human resilience to extreme temperatures and highlights the hitherto underestimated societal impact of climate change:
Conflicts in the digital world, affecting both societal cohesion and individual mental health.
Annika Stechemesser, lead author of the study, explains:
“By detecting aggressive tweets in more than four billion tweets from US users with our AI algorithm and combining them with weather data, we observed that the absolute number and share of hateful tweets increases outside of a climatic comfort zone: people tend to display more aggressive behavior online when it is too cold or too hot outside. »
This study also highlights the limits of our ability to adapt to extreme temperatures. Indeed, according to Anders Levermann, co-author and head of Complexity Science at the Potsdam Institute:
“Even in high-income areas where people can have air conditioning, an increase in hate speech has been observed during ‘extremely hot days.’ Thus, there are certainly limits of adaptation and these are lower than those set by our simple physiological limits. »
According to Leonie Wenz, head of the working group at the Potsdam Institute who led the PIK study, climate change can also be a harbinger of hate crimes around the world.
She reveals: “For centuries, researchers have grappled with the question of how climatic conditions affect human behavior and societal stability.
Our findings highlight online hate speech as a new impact channel through which climate change can affect overall societal cohesion and people’s mental health.
This therefore means that the very rapid and drastic reduction in emissions will not only benefit the outside world. Protecting our climate from excessive global warming is also essential for our mental health. »
This is not the first study to demonstrate the impact of climate on human behavior. In 2013, a study entitled “Quantifying the influence of climate on human conflicts” published in the journal Science concluded that: “Every 1 degree climate change towards warmer temperatures or more extreme rainfall increases the frequency of interpersonal violence by 4% and intergroup conflict by 14%. »
A study published in 2018 in the journal Nature Climate Change also revealed a link between the suicide rate and rising temperatures in the United States and Mexico.