Heat and Aggression
Losing Your Cool Craig Anderson and others conducted extensive research on the question of whether heat leads to aggression, and data across time, cultures, and methodologies (including in experiments to estab- lish a causal link) strongly support the notion that people lose their cool in hot temperatures and behave more aggressively. More violent crimes occur in the summer than in the winter, in hot years than in cooler years, and in hot cities than in cooler cities at any given time of year. Every year, the numbers of political uprisings, riots, homicides, assaults, rapes, and reports of violence peak in the summer months.
Hotter temperatures have even been associated with greater hostility on survey responses. Alexander Cohen and James Kruger (2016) found that when the temperature rose above 74ºF, people responding to surveys expressed more hostile attitudes concerning immigration and affirmative action policies.
With climate change having the potential to make hotter temperatures much more com- mon in years to come, some scholars have speculated about the effects this may have on aggression and violence. Matthew Ranson (2014), for example, conducted a sophisti- cated analysis of 30 years of monthly data on temperature and crime rates in nearly 3,000 counties in the United States. Based on these analyses, he estimates that global warming will cause an additional 22,000 murders, 1.2 million aggravated assaults, and a host of other criminal behaviors over the remainder of the century, at a financial cost of over $100 billion.
