The Misery Index

How does climate affect how you feel?

Well, you don't want to be 'left out in the cold'. And you like to feel all 'warm inside'. Figures of speech offer many clues about our aversion to cold weather and our love for sunny days. But, as always, there's more to it: physical and interpersonal warmth are related. A Science article points out that the area of the brain that senses temperature, the insular cortex, also lights up when we feel empathy toward somebody. So if you're physically warm you'll tend to be emotionally warm, whereas if you're cold your shoulder will be too. That's why people who feel lonely tend to linger in the shower for longer, or take frequent hot baths. It's also why raising the thermostat just a few degrees in an office environment will increase productivity. This is related to our ancestral need for warmth, because as mammals we can only afford to sway just a few degrees away from our ideal core temperature before our metabolism shuts down.

But weather can affect us in unpredictable ways. One of my favorite obscure psychological studies shows that admission rates at a Canadian medical school are lower for people who sustain their interviews on rainy days. And Campbell has done something that comes straight out of pure, unadulterated genius: they have created a Misery Index, which links the airing of their radio ads to cold, damp weather. Exactly when you're longing for hot soup.

Sunny days are not all good, though. There seems to be a statistical correlation between hot weather and an increase in crime rates. Common sense dictates that we spend more time outside when it's nice, creating more possibilities for incidents. But it also seems like a modest increase in the temperature of the brain can mess with our fight-or-flight instinct, generating aggressive behavior.