The first days of june They have broken a very dangerous global temperature record, by exceeding the 1.5ºC established as a limit in the Paris Agreement. This is only a preamble to what is coming as a very hot summer in the northern hemisphere. For this reason, people are already beginning to talk about the consequences of the heat waves that will come. Heat strokes, dehydration, burns… But what about sexual assaults, muggings, murders or even dog attacks? All these are cases of violence they appear to be driven by heat.
That of dogs in a recent studywhich joins many others, carried out both in humans and other animals. They all point to very similar conclusions: heat encourages violence, but why?
The truth is that this remains unclear, despite the wide range of studies on the subject that we can find in the scientific literature. However, there are some hypotheses, two of which currently have the most weight. One suggests that when temperatures rise, so do discomfort, frustration and impulsiveness, all of them perfect sparks to ignite the fire of violence. In fact, it has been seen that with the heat traffic accidents are also increasing, possibly because of that same impulsiveness. On the other hand, the other hypothesis indicates that when it is hot we spend more time doing outdoor activities, we interact more with other people and that can increase the probability of quarrels being generated. It is not clear which is the correct option, because it is possibly a mixture of both.
Examples of violence that increased with the heat
There are many studies pointing to the increase in violence caused by heat. In fact, already at the end of the 19th century, when the first reliable crime statistics, it was checked that crimes against people were more common in summer.
Also they uprisings of the people against the government, so common in the past, used to take place at this time of the year, regardless of the hemisphere. For example, most of the uprisings that took place in Europe in the 18th and 19th centuries occurred in July, while in South America they were much more common in January. Always at the beginning of summer.
These are all historical data, but in recent years a strong relationship between heat and violence has also been found. For example, a 2019 study found many more cases of organized crime in Mexico in hot periods. In the United Kingdom, was seen that there are 14% more violent crimes at 20ºC than at 10ºC. And in a study conducted in the United States it was observed that for each increase of 5 °C in the average daily temperature between 2007 and 2017 there were a 4-5% increase in sexual offences.
Also in Spain studies of this type have been carried out. For example, in 2018 one was published in which there was an increase in the reports of cases of gender violence during the heat waves that occurred between January 2008 and September 2016.
Also in animals
The increase in violence coinciding with the heat could be seen as something merely social. In that case, it would be much more common in humans. However, animal studies have also been conducted. with similar results.
For example, in 2013 an investigation was published which indicated an increase in rat aggressiveness coinciding with the heat. Something interesting about this study is that it was shown that the aggressiveness was not due to different stimuli associated with heat, since the stimulus that prompted the anger of the rodents was in all cases a small electric shock.
This was done at three different temperatures: 40ºF, 70ºF and 100ºF. Or what is the same, 4.4ºC, 21.1ºC and 37.78ºC. The more heat, the more violent was the response of the rats, especially with those final almost 40ºC.
It has also recently been seen that the cases of dog attacks on humans increase with the heat and even with the air pollution. The latter is an interesting fact that has also been observed in rhesus monkeysAlthough the causes are not clear.
Humans also attack animals more
We have seen that there are more dog attacks when it is very hot. But it also happens on the contrary. Since human violence increases with temperatures, it has been observed that cases of animal abuse are much more frequents during heat waves and, in general, when temperatures rise.
What hypothesis are we left with?
It is not clear which of the two hypotheses mentioned above would best explain this phenomenon. Possibly it is a mixture of both, It is clear that the heat puts us all in a bad mood. It would not be strange that this bad mood, in people predisposed to aggressionwould result in violence.
The same investigation that showed that in the 19th century crimes against persons were more abundant, also pointed out that burglaries They were more abundant in winter. All of this squares with this hypothesis.
Furthermore, in 1987 a study was published in which it was demonstrated that crime is not what increases with the heat. It compared the distribution of violent crime cases with non-violent crimes, such as the car theft. It was seen that only crimes accompanied by violence increased with heat, so both hypotheses would be supported.
The Spanish study also fits the second hypothesis. And it is that, although with the heat we spend more time outdoors, when it is very high, we take our bad mood home. For this reason, violent people will spend more time with their partners and the cases of violence could increase. gender violence.
Will violence increase with climate change?
Given all this, it is worrying to think about what is to come with climate change. The temperatures they are already breaking records and heat waves will become more frequent. Therefore, measures must be taken also counting on a possible increase in violent attacks.
In fact, according to a study published in 2014only in the United States could climate change lead by the end of the century to an increase in 22,000 murders, 1-2 million aggravated assaults and 2-3 million simple assaultscompared to 2010.
It is an effect of the heat that we do not stop to think about, but it is quite serious. Sometimes when we watch the news we feel like the world is going crazy and we don’t know why. Perhaps we should start thinking about heat as one of the causes.