How to Encourage More Climate-Friendly Habits, According to Science

Among many well-intentioned people working on the uneasy border between climate action and consumption-based capitalism, there’s long existed a consensus that consumers of everything from coffee to dry shampoo are basically rational creatures. If you can label which particular brand of toilet paper isn’t destroying the planet, you’ll help that bath tissue win in the marketplace, and put the bad toilet paper brands out of business. That’ll cut pollution, and help save the world. It hinges on toilet paper shoppers making sane decisions—but that seems like a fair assumption, right? They’d be crazy to keep buying the bad toilet paper when a better alternative exists.

The problem, though, is that people are a bit crazy, according to science. Earlier this week, researchers in Sweden, the U.K., and the U.S. released one of the most comprehensive reviews to-date of our research on what works in making people take action on climate, and what doesn’t. One of the topline findings is striking: expecting people to change their behavior based on simply telling them what is good or bad for the planet doesn’t work very well. Instead, the most powerful influence is what other people around you are doing.

Across hundreds of studies, which assessed situations from whether people chose meat or vegetarian food options to whether people tossed cans in a recycling bin or the trash, the researchers determined that subjects changed their behavior by an average of just 3% when they were educated about the climate consequences of their actions, like energy labels on products. That’s 3% less energy used, for instance, or 3% less meat consumed, or 3% fewer airline miles flown, and 3% less resultant airplane emissions. By contrast, when people were presented with financial incentives, they changed their behavior by 4 times as much, 12%, on average.

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“The problem with educational information is often that it doesn’t include any clear motive for people,” says Magnus Bergquist, a psychology lecturer at the University of Gothenburg in Sweden and the lead author on the study. “You know that you should exercise more, but you don’t do it, because just knowing you should do something isn’t sufficient motivation for you to actually do it.”

As it turns out, when it comes to taking action to stop climate change, the best way of changing people’s behavior is what the researchers termed “social comparisons,” which resulted in an average 14% change in people’s behavior. Basically, when people see that other people have taken a specific action, they’re likely to copy it. If you go into a restaurant bathroom, for instance, and find the light switch is off, you’re much more likely to turn it off when you leave. The same goes for people deciding to litter: people are far more likely to litter on a street already full of trash—which is evidence that others have littered before them—than on a clean sidewalk. And while it doesn’t do much to simply know that a certain product is more eco-friendly, if people see others buying that product instead of the dirty one, they’re much more likely to choose it themselves. “After all,” Bergquist says, “we are a highly social animal.”

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