How your environment affects your personality

The "frontier hypothesis," and other ways nature nurtures

Now is the winter of our discontent, but I wouldn’t know … I’m in Florida. Here, January means running outside in a tank top. I come here because I have seasonal affective disorder, or SAD, a disease whose main symptom is an overwhelming desire to stay in bed crying between November and March. How Victorian! Get me my fainting couch! It would be funny if it weren’t so SAD.

The weather’s extreme effect on my personality got me thinking about how our natural environments can imprint themselves on our dispositions. We’ve all met Californians who seem as laid back and sunny as Redondo Beach. Last fall I took a trip to London, where it rained so hard that it stunned even Brits into a sullen silence. I always thought these were mere stereotypes, but it turns out there’s some research to support the idea that the weather, and natural features like water and mountains, can, in fact, affect how we think and feel.

The perennial recap of these posts is that there are five main personality traits:

Openness to experience — you enjoy novelty, art, and new ideas

Conscientiousness — you’re timely, tidy, and organized

Extroversion — YAAS queen!

Agreeableness — you just want everyone to get along

Neuroticism — you’re anxious and depressed. (The opposite is emotional stability).

One study, for instance, found that people in China and the U.S. who grew up in areas where the average temperature was closer to 72 degrees Fahrenheit were higher on all five of the Big Five traits. That is, they were more open to experiences, conscientious, agreeable, extroverted, and emotionally stable (the opposite of neurotic), which together means they had “healthier” personalities. People from warm hometowns, that is, literally became warmer.

This connection is rather self-explanatory: Temperate climates provide plenty of mood-boosting Vitamin D. They feel nice and promote going outdoors and socializing. Through that socializing, people become both more extroverted and more open to experiences, since all the other people they meet expose them to new points of view. All that mingling might force them to behave agreeably. (You’re supposed to share the wave when you’re surfing, dude!)

A co-author of that study, that Cambridge psychologist Jason Rentfrow, has also found that people living in mountainous areas of the American West tend to be lower in agreeableness, conscientiousness, extroversion, and neuroticism, but higher on openness to experience. In other words, mountain-dwellers tend to be less trusting and outgoing, but they are also rugged and resilient, as evidenced by their high levels of emotional stability. They are quick to break society’s rules (low conscientiousness) but also to consider new possibilities (high openness to experience.)

The explanation behind this is the “frontier hypothesis,” or the idea that the mountains have historically attracted settlers who were independent, individualistic, and motivated to solve problems. Some of those norms and attitudes were passed down through generations, creating a shared culture that is relaxed and open-minded, but not very sociable. 

In fact, as I’ve written previously for The Atlantic, Rentfrow suspects the U.S. can be broken down in to three different psychological “regions.” The Midwest and parts of the Southeast are, according to his research, “friendly and conventional,” meaning high in extroversion, agreeableness, and conscientiousness. There, people value tradition and family; they are “Minnesota nice.” The West Coast, meanwhile, is relaxed and open to experiences. People there prize tolerance and individualism. Alas, both Texas, my onetime home, and the Northeast, my current home, are “temperamental and uninhibited,” with high levels of neuroticism.

Rentfrow et al

Though Texas’ high neuroticism is a bit of a head-scratcher, Rentfrow attributes the moodiness of the East Coast in part to dismal weather and crowded living conditions. That, and people who are already dyspeptic and depressed might move to dyspeptic, depressing East-Coast cities.

In all of my research on environment’s effect on personality, the most interesting finding I came across was this: People who have seasonal affective disorder tend to be higher in openness to experience than those who don’t have SAD. This is strange because, as is the case with all of the Big Five, more openness tends to be better. But in this case, more openness appears to be worse, turning you a fragile, winter-hating little rosebud. The authors of this study hypothesize this might be because open people and those with SAD are both unusually attuned to their emotions and sensitive to their environments—including, unfortunately, sensitive to months when the environment sucks. As someone very high on openness who also suffers from SAD, I can relate.

It’s worth noting that personality is influenced by hundreds of factors, so even though these environmental influences are there, they’re small. Just because you were born in a cold place (like I was!) doesn’t mean you’re doomed to a life of gloominess. But these studies might help explain why you—and your neighbors—have certain tendencies that seem otherwise inexplicable.