Finally, Belkin and her co-author asked university students to take part in an experiment to see if a slight fluctuation in temperature was enough to influence behaviour. The students were divided into two lecture theatres, one that was uncomfortably warm and one that was air conditioned. They then asked the students to fill out a survey “for a non-profit organisation that serves children and underprivileged individuals in the local community”.

Even though there was only a 15% difference in the actual temperatures, the students in the hotter room were 31% less likely to volunteer to help. Interestingly, even those individuals who did offer to help still helped much less than the students in the air conditioned room: on average, they answered only six survey questions, compared to 35 in the cooler lecture hall.

“The point of our study is that ambient temperature affects individual states that shape emotional and behavioral reactions,” says Belkin, “so people help less in an uncomfortable environment, whatever the reason they come up with to justify why they cannot do [something]”.

So there you have it: summer = moody and unhelpful. It’s science.

Images: iStock, Rex Features

There’s a scientific reason why summer turns you into a horrible person