Baby, is it cold outside?

Dramatic spikes and drops in atmospheric temperature correspond with surges of hate tweets, a study by researchers at Germany’s Potsdam Institute for Climate Impact Research, published in the journal Lancet Planetary Health in September, has found.

The study used an AI algorithm to analyse over 4 billion tweets posted in the US between 2014 and 2020 and found that the number of hate tweets increased in areas of extremely hot or cold climactic conditions, irrespective of social and economic factors.

Hate tweets, incidentally, were defined (in keeping with UN standards) as “attacks or uses of pejorative or discriminatory language with reference to a person or a group on the basis of… religion, ethnicity, nationality, race, colour, descent, gender or other identity factor”.

“Even in high-income areas where people can afford air conditioning and other heat mitigation options, we observe an increase in hate speech on extremely hot days,” Anders Levermann, head of complexity science research at the institute and a co-author of the study, said in a statement.

The fewest hate tweets were found in areas where temperatures remained in the pleasant range of 15 to 18 degrees Celsius. The number of hate tweets rose by 22% in extremely hot weather (ambient temperatures of 42 to 45 degrees Celsius) and by 12.5% on extremely cold days (ambient temperatures of -6 to -3 degrees Celsius).

The targets tended to be minorities such as blacks, Hispanics and members of the LGBTQ+ community, the study found.