Study links hot climates to violent crimes

Researchers in a study published in the journal Behavioural and Brain Sciences have established a correlation between hot climates and violent crimes.
The report said that hot climates and less variation in seasonal temperatures lead to a faster life strategy, less focus on the future and less self-control all of which contribute to more aggression and violence, thus giving an expanded meaning to the term ‘hot headed’.

Several studies have shown that the average temperatures in most Arabian countries and Africa are between 33 degree Celsius and 45 degree Celsius, which is very hot.

According to research by a University of Montana team using data from the United States (U.S.) Geological Survey’s Landsat satellites, Lut Desert in Iran and El Azizia in Libya, shared the title of the hottest places on earth with temperatures reaching 58 degrees Celsius (136 degrees Fahrenheit).

The team of researchers has developed a model that helps explain why and goes beyond the simple fact that hotter temperatures seem to be linked to more aggressive behaviour.

The article entitled, Aggression and Violence Around the World: A Model of CLimate, Aggression and Self-control in Humans (CLASH) was published by Paul A. M. Van Lange, Maria I. Rinderu and Brad J. Bushman in the journal Behavioural and Brain Sciences.

Co-author of the study and Professor of Communication and Psychology at the Ohio State University, United States (U.S.), Brad Bushman, said: “Climate shapes how people live, it affects the culture in ways that we don’t think about in our daily lives.”

Paul van Lange, lead author of the study and a Professor of Psychology at the Vrije Universiteit Amsterdam (VU) added: “We believe our model can help explain the impact of climate on rates of violence in different parts of the world.”

The researchers, including Maria I. Rinderu who call the new model CLASH say many studies have shown that levels of violence and aggression are higher in hot climates.

“But the two leading explanations of why that is so aren’t satisfactory,” Bushman said.The General Aggression Model(GAM) which Bushman helped develop, suggests hot temperatures make people uncomfortable and irritated, and so more aggressive.

“But that doesn’t explain more extreme acts, such as murder,” he said.Another explanation, Routine Activity Theory(RAT) is that people are outdoors and interacting more with others when the weather is warm, which leads to more opportunities for conflict.

But that doesn’t explain why there’s more violence when the temperature is 95 degrees F (35 °C) than when it is 75 degrees F (24 °C) – even though people might be outside under both circumstances.

The CLASH model states that it is not just hotter temperatures that lead to more violence – it is also climates that have less seasonal variation in temperature.

“Less variation in temperature, combined with heat, brings some measure of consistency to daily life,” Rinderu said.That means there is less need to plan for large swings between warm and cold weather. The result is a faster life strategy that isn’t as concerned about the future and leads to less need for self-control.

“Strong seasonal variation in temperature affects culture in powerful ways. Planning in agriculture, hoarding, or simply preparing for cold winters shapes the culture in many ways, often with people not even noticing it. But it does shape how much a culture values time and self-control,” Van Lange said.

“If there is less variation, you’re freer to do what you want now, because you’re not preparing foods or chopping firewood or making winter clothes to get you through the winter. You also may be more concerned with the immediate stress that comes along with parasites and other risks of hot climates, such as venomous animals.”